Biosensors

Abstract

We provide a biosensor that can measure biological information with a simple configuration. [Solution] The biosensor according to the present invention is a biosensor that is attached to a living body and comprises an electrode provided on the living body side of a sensor body that acquires biological information, and a substrate provided on the living body side or the opposite side of the living body from the electrode and having an exposed portion that exposes a part of the electrode, wherein the electrode is in contact with the sensor body or the living body via the exposed portion.

Description

Technical Field

[0001] The present invention relates to a biosensor.

Background Art

[0002] In medical institutions such as hospitals and clinics, nursing facilities, homes, etc., for example, wearable biosensors for acquiring biological information such as electrocardiogram waveforms, pulse waves, brain waves, and myoelectricity are used. The biosensor includes a bioelectrode that contacts the living body to acquire the biological information of the subject. When measuring the biological information, the biosensor is attached to the skin of the subject, and the bioelectrode acquires an electrical signal related to the biological information, thereby measuring the biological information.

[0003] As such a biosensor, for example, there is disclosed a physiological monitoring device having two housings, a flexible body connected to the housing, and two gaskets sandwiched between the housing and the flexible body, and the flexible body is composed of two base material layers, an electrode sheet disposed between the base material layers, and an electrode attached to the bottom surface of the base material layer on the bottom side (see, for example, Patent Document 1).

[0004] The physiological monitoring device is configured to facilitate attachment of the flexible body to the housing with a gasket and to waterproof the housing with the gasket. In the physiological monitoring device, the electrode makes an isometric contact with the patient's surface to detect a physiological signal from the patient, and transmits an electrical signal from the electrode to an electronic device housed in the housing.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the physiological monitoring device described in Patent Document 1 had the problem that, in addition to the housing and flexible body, it required many components to make up the device, such as providing two gaskets to ensure waterproofing.

[0007] One aspect of the present invention aims to provide a biosensor capable of measuring biological information with a simple configuration. [Means for solving the problem]

[0008] One aspect of the biosensor according to the present invention is: A biosensor that is attached to a living body, An electrode provided on the biological side of the sensor body that acquires biological information, A substrate provided on the side of the electrode that is on the side of the living body or the side that is on the opposite side of the living body, having an exposed portion that exposes a part of the electrode, Equipped with, The electrode is a biosensor that contacts the sensor body or the living body via the exposed portion. [Effects of the Invention]

[0009] One embodiment of the biosensor according to the present invention can measure biological information with a simple configuration. [Brief explanation of the drawing]

[0010] [Figure 1] This is a perspective view showing the appearance of a biosensor according to an embodiment of the present invention. [Figure 2] This is a perspective view showing the individual components of a biosensor in a disassembled state. [Figure 3] This is another perspective view showing the individual components of the biosensor in a disassembled state. [Figure 4] This is a cross-sectional view II in Figure 1. [Figure 5] This is a cross-sectional view taken along line II-II in Figure 1. [Figure 6] This is an explanatory diagram showing the biosensor in Figure 1 attached to the chest of a living organism. [Figure 7]It is an exploded perspective view showing an example of another configuration of the biosensor. [Figure 8] It is an exploded perspective view showing an example of another configuration of the biosensor.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described in detail. For ease of understanding of the description, the same reference numerals are given to the same components in each drawing, and duplicate descriptions are omitted. Also, the scales of the respective members in the drawings may be different from the actual ones. In this specification, "~" indicating a numerical range means including the numerical values described before and after it as the lower limit value and the upper limit value, unless otherwise specified.

[0012] <Biosensor> The biosensor according to this embodiment will be described. Here, the living body refers to a human body (person), as well as animals such as cows, horses, pigs, chickens, dogs, and cats. The biosensor according to this embodiment can be preferably used for a living body, particularly for a human body. In this embodiment, as an example, the case where the living body is a human will be described.

[0013] The biosensor according to this embodiment is a sticker-type biosensor that is attached to a part of a living body (for example, skin, scalp, forehead, etc.) to measure biological information. In this embodiment, the case where the biosensor is attached to a person's skin to measure an electrical signal (biological signal) related to the person's biological information will be described. The biological signal is, for example, an electrical signal representing an electrocardiogram waveform, brain wave, pulse, etc.

[0014] FIG. 1 is a perspective view showing the appearance of the biosensor according to this embodiment, FIG. 2 is a perspective view showing the state where the components of the biosensor are disassembled, FIG. 3 is another perspective view showing the state where the components of the biosensor are disassembled, FIG. 4 is a longitudinal sectional view of the biosensor, the cross-sectional view I-I of FIG. 1, and FIG. 5 is a cross-sectional view taken along II-II of FIG. 1.

[0015] As shown in FIG. 1, the biological sensor 1 is a plate-shaped (sheet-shaped) member that is formed in a substantially rectangular shape in a plan view, with both ends in the longitudinal direction formed in an arc shape and the central portion in the longitudinal direction formed to be larger in the width direction. As shown in FIGS. 2 and 3, the biological sensor 1 includes a first base material 10, electrodes 20, a second layer member 30, a pair of housings 40, and a sensor unit 50. As shown in FIG. 4, the biological sensor 1 is formed by laminating the first base material 10, the electrodes 20, and the second layer member 30 in this order and sandwiching them with a pair of housings 40. In the biological sensor 1, the electrodes 20, the second layer member 30, and one of the housings 40 form a surface for attaching to the skin 2, which is a living body. The biological sensor 1 measures an electrical signal (biological signal) related to the biological information of the subject by attaching the attachment surface to the skin 2 and measuring the potential difference (polarization voltage) between the skin 2 and the electrodes 20.

[0016] In FIGS. 1 to 5, a three-dimensional orthogonal coordinate system in three axial directions (X-axis direction, Y-axis direction, Z-axis direction) is used. The short side direction of the biological sensor is the X-axis direction, the long side direction is the Y-axis direction, and the height direction (thickness direction) is the Z-axis direction. The opposite direction (outer side) to the side (attachment side) where the biological sensor 1 is attached to the living body (subject) is the +Z-axis direction, and the attachment side is the -Z-axis direction. In the following description, for convenience of explanation, the +Z-axis direction may be referred to as the upper side or up, and the -Z-axis direction may be referred to as the lower side or down, but it does not represent a universal up and down relationship.

[0017] The inventor of the present application manufactured a biological sensor 1 in which the first base material 10, the electrodes 20, and the second layer member 30 were laminated and sandwiched and fixed with a pair of housings 40 from the outside of the first base material 10 and the outside of the second layer member 30. The inventor of the present application provided exposed portions 13 and 30a on the first base material 10 and the second layer member 30, and by exposing a part of the electrodes 20 therefrom, the electrodes 20 were configured to contact the sensor unit 50 and the skin 2 through the exposed portions 13 and 30a. As a result, the inventor of the present application noticed that only the electrodes 20 can play the roles of acquiring biological information from the skin 2 and transmitting the acquired biological information to the sensor unit 50. As a result, the inventor of the present application found that the biological sensor 1 can acquire and measure biological information from the skin 2 while having a simple configuration.

[0018] [First base material] As shown in Figures 2 and 3, the first substrate 10 is provided on the side opposite to the skin 2 side relative to the electrode 20. The electrode 20 is provided on the lower surface 101 of the first substrate 10, which is the side facing the skin 2. The electrode 20 may be provided on at least a portion of the lower surface 101 of the first substrate 10. The first substrate 10 is formed in a sheet shape. In a plan view of the biosensor 1, the first substrate 10 may be formed so that both ends in the longitudinal direction are arc-shaped and the central part is wider in the width direction.

[0019] The first substrate 10 has a through hole 12 in a plan view of the biosensor 1 at a position corresponding to the projection 412 of the first housing 41. The through hole 12 may be formed to be large enough for the projection 412 of the first housing 41 to pass through.

[0020] The shape of the through-hole 12 is not particularly limited as long as the projection 412 can pass through it, and it may be rectangular, circular, or the like.

[0021] The through-holes 12 are provided in the first substrate 10 in a plan view of the biosensor 1 so as to correspond to the protrusions 412, but the number of through-holes 12 can be three or fewer, or five or more, as long as they are in positions corresponding to the protrusions 412.

[0022] The first base material 10 is fixed to the surface of the first base material 10 by a pair of housings 40, with the projection 412 of the first housing 41 of the pair of housings 40 being locked to the locking portion 421 of the second housing 42 of the pair of housings 40.

[0023] The first substrate 10 has an exposed portion 13 at a position facing the sensor portion 50. The exposed portion 13 is formed in a substantially circular shape in a plan view of the biosensor 1 and may be smaller than the opposing portions 201A and 201B of the electrode 20. The exposed portion 13 should be formed such that it exposes the opposing portions 201A and 201B of the electrode 20 and has an area that allows the opposing portions 201A and 201B to be stably connected to terminals (not shown) of the sensor portion 50. By exposing a part of the electrode 20 from the exposed portion 13, the electrode 20 and the sensor portion 50 can be brought into contact at the exposed portion 13.

[0024] The shape of the exposed portion 13 in plan view is not particularly limited as long as the opposing portions 201A and 201B of the electrode 20 are exposed, and other shapes other than a roughly circular shape, such as a roughly rectangular or roughly elliptical shape, may also be used.

[0025] Two exposed portions 13 are provided so as to correspond to terminal portions (not shown) of the sensor portion 50 in a plan view of the biosensor 1. However, they only need to be in positions corresponding to terminal portions (not shown) of the sensor portion 50, and the number of exposed portions 13 may be one or three or more.

[0026] The first substrate 10 may be made of a substrate that exhibits flexibility, waterproofing, and breathability. The flexibility, waterproofing, and breathability of the first substrate 10 allow it to stretch easily when in contact with the skin 2 and maintain contact with the skin 2. Furthermore, water vapor from sweat and other sources generated from the skin 2 to which the biosensor 1 is attached can be released to the outside of the biosensor 1 via the first substrate 10. Therefore, the first substrate 10 can more easily maintain its adhesive durability.

[0027] The moisture permeability of the first substrate 10 is not particularly limited, but is 100 g / (m²). 2 • day) ~ 5000g / (m 2 The moisture permeability of the first substrate 10 may be set to 100 g / (m²). 2 • day) ~ 5000g / (m 2 By doing this (day), the first substrate 10 can allow water vapor that has entered from one side to pass through the first substrate 10 and be stably released from the other side.

[0028] The method for calculating the moisture permeability of the first substrate 10 is not particularly limited and a general method can be used. For example, it can be calculated using the following procedure. (1) Prepare a weighing bottle having an opening with a predetermined area S, and pour enough water into the weighing bottle so that the liquid level is below the opening. (2) Place a part or all of the first substrate 10 as a measurement sample on the entire surface of the opening of the weighing bottle so that no tension is generated on the first substrate 10, fix the measurement sample in the weighing bottle, and seal the weighing bottle. (3) Measure the total mass M1 of the sample, water, and weighing bottle immediately after sealing. (4) Leave the sealed weighing bottle at 40°C and 30% RH for 24 hours. (5) Measure the total mass M2 of the sample, water, and weighing bottle after 24 hours of standing. (6) Calculate the moisture permeability P from the following formula (1). Moisture permeability P=(total mass M1-total mass M2) / predetermined area S...(1)

[0029] The first base material 10 may be formed from a base material that does not have a porous structure, or from a base material that has a porous structure, as long as it is a base material that can exhibit flexibility, waterproofing, and moisture permeability.

[0030] As materials for forming a substrate that does not have a porous structure, thermoplastic resins such as polyurethane resins, polystyrene resins, polyolefin resins, silicone resins, acrylic resins, vinyl chloride resins, and polyester resins can be used. When the first substrate 10 is formed from a substrate that does not have a porous structure, the first substrate 10 may be, for example, a polyurethane sheet such as Esmer URS manufactured by Nippon Matai.

[0031] The substrate having a porous structure may be formed using a porous material that is flexible, waterproof, and breathable. As the porous material, for example, a foamed material (foam) having a cellular structure such as open-cell, closed-cell, or semi-closed-cell can be used. This allows water vapor from sweat etc. generated from the skin 2 to which the biosensor 1 is attached to be released to the outside of the biosensor 1 via the first substrate 10.

[0032] As the material for forming the porous body, thermoplastic resins such as polyurethane resins, polystyrene resins, polyolefin resins, silicone resins, acrylic resins, vinyl chloride resins, and polyester resins can be used, as described above. When the first base material 10 is formed from a porous body, for example, FOLEC manufactured by Inoac Corporation may be used as the first base material 10.

[0033] The thickness of the first substrate 10 can be set as appropriate, and is preferably 0.5 mm to 1.5 mm, and more preferably 0.5 mm to 1.0 mm. If the thickness of the first substrate 10 is 0.5 mm to 1.5 mm, the first substrate 10 can suppress the intrusion of moisture from the outside, ensure waterproofness, and also have flexibility and breathability, which is preferable.

[0034] In this specification, the thickness of the first substrate 10 refers to the length perpendicular to the main surface of the first substrate 10. The thickness of the first substrate 10 may be, for example, the thickness measured at any point in the cross-section of the first substrate 10, or it may be the average value of measurements taken at several points in any location. Hereafter, the definition of thickness will be the same for other components.

[0035] [electrode] As shown in Figure 4, the electrode 20 is provided on the lower surface 101 of the first substrate 10, which is the surface on the attachment side (-Z axis direction). The electrode 20 is positioned sandwiched between the first substrate 10 and the second layer member 30.

[0036] The electrode 20 contacts the sensor portion 50 at the exposed portion 13 of the first substrate 10 and contacts the skin 2 at the exposed portion 30a of the second layer member 30. That is, a part of the electrode 20 contacts a terminal (not shown) of the sensor portion 50 via the exposed portion 13 of the first substrate 10, and another part contacts the skin 2 via the exposed portion 30a of the second layer member 30. When the biosensor 1 is attached to the skin 2, the electrode 20 contacts the skin 2 and the terminal (not shown) of the sensor portion 50, allowing the electrode 20 to detect a biological signal at the portion in contact with the skin 2 and transmit the detected biological signal to the terminal (not shown) of the sensor portion 50. The electrode 20 may be embedded in a state where it is exposed to the exposed portion 13 of the first substrate 10 so as to be able to contact the sensor portion 50, or it may be embedded in a state where it is exposed to the exposed portion 30a of the second layer member 30 so as to be able to contact the skin 2.

[0037] The electrode 20 consists of a pair of electrodes 20A and 20B. As shown in Figures 2 and 3, electrode 20A is positioned on the left side in the figures, and electrode 20B is positioned on the right side in the figures. One end (inside) of electrode 20A in its longitudinal direction (Y-axis direction) is in contact with a terminal (not shown) of the sensor unit 50, and one end (inside) of electrode 20B in its longitudinal direction (Y-axis direction) is in contact with a terminal (not shown) of the sensor unit 50. The pair of electrodes 20A and 20B may have substantially the same shape.

[0038] Furthermore, one end of electrode 20A that contacts a terminal (not shown) of sensor unit 50 is designated as opposing portion 201A, and one end of electrode 20B that contacts a terminal (not shown) of sensor unit 50 is designated as opposing portion 201B. On electrode 20A, the side of the exposed portion 30a of the second layer member 30 is designated as exposed portion 202A, and on electrode 20B, the side of the exposed portion 30a of the second layer member 30 is designated as exposed portion 202B.

[0039] The electrode 20 may have any shape, such as a sheet.

[0040] The shape of electrode 20 in plan view is not particularly limited and may be designed to any shape as appropriate depending on the application. As shown in Figures 2 and 3, electrodes 20A and 20B may have circular opposing portions 201A and 201B at one end (inside) and circular exposed portions 202A and 202B at the other end (outside). The connecting portions 203A and 203B between the opposing portions 201A and 201B and the exposed portions 202A and 202B may be formed in a rod shape.

[0041] The shape and size of the exposed portions 202A and 202B are not particularly limited as long as they do not fall into the exposed portion 30a of the second layer member 30. It is preferable that the exposed portions 202A and 202B are formed to be larger than the exposed portion 30a of the second layer member 30 in a plan view of the biosensor 1. If the shape of the exposed portions 202A and 202B in a plan view is larger than the exposed portion 30a of the second layer member 30, it is possible to prevent the exposed portions 202A and 202B from falling into the exposed portion 30a. Since the exposed portions 202A and 202B are formed to be substantially circular, it is sufficient that the diameter of the exposed portions 202A and 202B is larger than the diameter of the exposed portion 30a. It is preferable that the exposed portions 202A and 202B are formed to be large enough that their outer circumferences remain sandwiched between the first base material 10 and the second layer member 30.

[0042] The electrode 20 can be formed using a cured product of a conductive composition containing a conductive polymer and a binder resin, a metal, an alloy, etc. In particular, from the viewpoint of biosafety, such as preventing allergic reactions when the electrode 20 is applied to a living body, it is preferable to form the electrode 20 using a cured product of a conductive composition.

[0043] Examples of conductive polymers that can be used include polythiophene-based conductive polymers, polyaniline-based conductive polymers, polyacetylene-based conductive polymers, polypyrrole-based conductive polymers, polyphenylene-based conductive polymers and their derivatives, as well as composites thereof. Among these, a composite obtained by doping polyaniline as a dopant to polythiophene is preferred. Among the composites of polythiophene and polyaniline, it is more preferable to use PEDOT / PSS, which is obtained by doping poly(3,4-ethylenedioxythiophene) (also called PEDOT) as the polythiophene and polystyrene sulfonic acid (poly4-styrene sulfonate; PSS) as the polyaniline, because it has a lower contact impedance with living organisms and higher conductivity.

[0044] The binder resin can be a water-soluble polymer or a water-insoluble polymer. As a water-soluble polymer, hydroxyl group-containing polymers such as polyvinyl alcohol (PVA) and modified PVA can be used.

[0045] The conductive composition may contain various common additives such as crosslinking agents and plasticizers in appropriate proportions. Examples of crosslinking agents include aldehyde compounds such as sodium glyoxylate. Examples of plasticizers include glycerin, ethylene glycol, and propylene glycol.

[0046] Common metals and alloys such as Au, Pt, Ag, Cu, and Al can be used as metals and alloys.

[0047] Alternatively, the electrode 20 may be an adhesive electrode formed in a sheet shape (adhesive electrode). If the electrode 20 is adhesive, it is attached to the lower surface 101 of the first substrate 10. The adhesive electrode may be formed using a conductive composition containing a conductive polymer, an aqueous emulsion adhesive, a humectant, and a neutralizing agent.

[0048] The conductive polymer contained in the adhesive electrode is the same as described above, so details are omitted.

[0049] The water-based emulsion adhesive contained in the adhesive electrode is used as a binder resin for the adhesive electrode. The water-based emulsion adhesive has the function of improving the adhesiveness and flexibility of the adhesive electrode. Therefore, by including the water-based emulsion adhesive in the adhesive electrode, the adhesive electrode can be made less elastic and its ability to conform to the irregularities on the surface of the skin 2 can be improved.

[0050] As the water-based emulsion adhesive, it is preferable to use an acrylic emulsion adhesive.

[0051] For acrylic emulsion adhesives, it is preferable to use a silane-based emulsion adhesive that contains a water-dispersible copolymer and an organic liquid component compatible with the water-dispersible copolymer.

[0052] Water-dispersible copolymers are polymers obtained by copolymerizing a monomer mixture containing an alkyl (meth)acrylate with a silane monomer copolymerizable with the alkyl (meth)acrylate.

[0053] A monomer mixture containing alkyl methacrylate is a monomer mixture that contains alkyl methacrylate as the main component, preferably in an amount of 50 wt% to 100 wt%.

[0054] As the alkyl (meth)acrylate ester, a linear or branched alkyl ester having 1 to 15 carbon atoms in the alkyl group, preferably 1 to 9 carbon atoms, is used. Specifically, examples include alkyl (meth)acrylate esters 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, and tridecyl (meth)acrylate. These can be used alone or in combination of two or more.

[0055] A monomer mixture containing an alkyl (meth)acrylate may also contain a carboxyl group-containing monomer copolymerizable with the alkyl (meth)acrylate.

[0056] The carboxyl group-containing monomer copolymerizable with alkyl (meth)acrylate is not particularly limited as long as it is a polymerizable compound containing a carboxyl group in its structure and copolymerizable with alkyl (meth)acrylate, but examples include (meth)acrylic acid, itaconic acid, maleic acid, maleic anhydride, and 2-methacryloyloxyethyl succinic acid. Acrylic acid is particularly preferred.

[0057] From the viewpoint of hydrolysis of the silane monomer and adjustment of the resulting viscosity, it is preferable to include the carboxyl group-containing monomer in an amount of 0.1 wt% to 10 wt% relative to 100 wt% of the monomer mixture containing the alkyl (meth)acrylate.

[0058] Silane monomers copolymerizable with alkyl (meth)acrylates are not particularly limited as long as they are polymerizable compounds having silicon atoms and copolymerizable with alkyl (meth)acrylates. However, silane compounds having a (meth)acryloyl group, such as (meth)acryloyloxyalkylsilane derivatives, are preferred because they exhibit excellent copolymerizability with alkyl (meth)acrylates. Examples of silane monomers include 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropyltriethoxysilane, 3-(meth)acryloyloxypropylmethyldimethoxysilane, and 3-(meth)acryloyloxypropylmethyldiethoxysilane. These silane monomers can be used individually or in combination of two or more.

[0059] In addition, other silane monomers that can be used include, for example, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, and 10-acryloyloxydecyltriethoxysilane.

[0060] It is preferable to copolymerize the silane monomer with a monomer mixture containing an alkyl (meth)acrylate at a concentration of 0.005 wt% to 2 wt% per 100 wt% of the monomer mixture containing the alkyl (meth)acrylate.

[0061] By copolymerizing silane monomers with a monomer mixture containing alkyl (meth)acrylate esters, the silane compounds that act as crosslinking points are uniformly distributed within the molecules of the resulting copolymer. As a result, the aqueous emulsion adhesive, despite being water-dispersible, exhibits excellent cohesiveness because the inside and outside of the particles are uniformly crosslinked. In addition to being low in skin irritation due to the addition of organic liquid components, it also possesses excellent fixation and sweat-resistant properties.

[0062] The water-dispersible copolymer may, if necessary, be obtained by copolymerizing monomers copolymerizable with alkyl (meth)acrylates other than the silane monomers and carboxyl group-containing monomers mentioned above. Monomers copolymerizable with alkyl (meth)acrylates other than silane monomers and carboxyl group-containing monomers can be used for purposes such as adjusting the cohesive force of adhesive electrodes when forming water-based emulsion adhesives into sheets, or improving compatibility with organic liquid components. The amount used can be arbitrarily set according to the purpose by substituting a portion of the alkyl (meth)acrylate content.

[0063] Monomers copolymerizable with alkyl (meth)acrylates other than silane monomers and carboxyl group-containing monomers include, for example, sulfoxyl group-containing monomers such as styrene sulfonic acid, allyl sulfonic acid, sulfopropyl (meth)acrylate, (meth)acryloyloxynaphthalene sulfonic acid, and acrylamide methylpropane sulfonic 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 methoxypropyl (meth)acrylate. Examples include ethyl esters, ethoxyethyl (meth)acrylate alkoxyalkyl esters such as (meth)acrylate, methoxyethylene glycol (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, methoxyethylene glycol (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypolypropylene glycol (meth)acrylate, etc., containing alkoxy groups (or ether links in the side chain), vinyl monomers such as (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.

[0064] Aqueous dispersible polymers can be prepared, for example, by subjecting a mixture of monomers containing an alkyl (meth)acrylate ester and a silane monomer to conventional emulsion polymerization, thereby producing an aqueous dispersion of an alkyl (meth)acrylate copolymer.

[0065] Common polymerization methods such as batch polymerization, continuous dropwise polymerization, and segmented dropwise polymerization can be employed, and the polymerization temperature is, for example, 20°C to 100°C.

[0066] The polymerization initiator used in polymerization is not particularly limited, and general components used as polymerization initiators can be used.

[0067] A chain transfer agent may be used to adjust the degree of polymerization. The chain transfer agent is not particularly limited, and general components used as chain transfer agents can be used.

[0068] In addition to the method described above, the water-dispersible copolymer may also be prepared by obtaining a copolymer of a monomer mixture containing (meth)acrylic acid ester and a silane monomer by a method other than emulsion polymerization, and then dispersing it in water with an emulsifier.

[0069] The organic liquid components contained in the acrylic emulsion adhesive, when incorporated into a water-dispersible copolymer, maintain good adhesion to the surface of the skin 2, reduce keratin damage during peeling from the surface of the skin 2, and also reduce pain during peeling.

[0070] The organic liquid component is preferably liquid at room temperature and has good compatibility with the water-dispersible copolymer. "Compatibility" refers to a state where the organic liquid component is uniformly dissolved and incorporated into the water-dispersible copolymer, and separation cannot be observed visually.

[0071] Examples of organic liquid components include esters of monobasic or polybasic acids with 8 to 18 carbon atoms and branched alcohols with 14 to 18 carbon atoms, and esters of unsaturated fatty acids or branched acids with 14 to 18 carbon atoms and alcohols with tetrahydride or less.

[0072] Examples of esters of monobasic or polybasic acids with 8 to 18 carbon atoms and branched alcohols with 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.

[0073] Examples of unsaturated or branched fatty acids with 14 to 18 carbon atoms include myristoleic acid, oleic acid, linoleic acid, linolenic acid, isopalmitic acid, and isostearic acid.

[0074] Examples of alcohols with a tetravalent or lower valency include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, and sorbitan.

[0075] The content of the organic liquid component can be arbitrarily set as appropriate depending on the type of water-dispersible copolymer and organic liquid component, for example, it may be 20 wt% to 80 wt% relative to 100 wt% of the water-dispersible copolymer.

[0076] When the acrylic emulsion adhesive is a silane emulsion adhesive, the acrylic emulsion adhesive can specifically be a silane emulsion adhesive containing 2-ethylhexyl acrylate, methyl methacrylate, acrylic acid, and 3-methacrylateoxypropyltrimethoxysilane.

[0077] Furthermore, acrylic emulsion adhesives can be two- or three-component acrylic emulsion adhesives containing a monomer mixture including an alkyl (meth)acrylate ester and a carboxyl group-containing monomer. These may contain solvents and other components in appropriate amounts within a range that allows them to perform effectively.

[0078] The monomer mixtures containing alkyl (meth)acrylates in two- or three-component acrylic emulsion adhesives are similar to the monomer mixtures containing alkyl (meth)acrylates in the silane-based emulsion adhesives described above, so details are omitted.

[0079] The carboxyl group-containing monomer is preferably a carboxyl group-containing monomer copolymerizable with alkyl (meth)acrylate. Since the carboxyl group-containing monomer copolymerizable with alkyl (meth)acrylate is the same as the carboxyl group-containing monomer included in the above-mentioned monomer mixture containing alkyl (meth)acrylate, details are omitted.

[0080] Specifically, as a two-component acrylic emulsion adhesive, an adhesive can be used that contains 2-ethylhexyl acrylate, which is a monomer mixture containing an alkyl (meth)acrylate ester, and acrylic acid, which is a monomer mixture containing a carboxyl group.

[0081] Specifically, as a three-component acrylic emulsion adhesive, an adhesive can be used that contains 2-ethylhexyl acrylate and methyl methacrylate, which are monomer mixtures containing alkyl (meth)acrylate esters, and acrylic acid, which is a monomer mixture containing carboxyl groups.

[0082] 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 strength and water resistance can be imparted to the adhesive electrode.

[0083] The shape of the aqueous emulsion adhesive is not particularly limited and may be spherical, ellipsoidal, fusiform, crushed, plate-like, columnar, etc.

[0084] The average particle diameter refers to the volume-average particle diameter based on the effective diameter. The average particle diameter is the particle diameter (median diameter) at which the cumulative amount of the smallest particles accounts for 50% of the volume in the particle size distribution curve obtained by measuring the particle size distribution of an emulsion adhesive or acrylic emulsion adhesive using methods such as laser diffraction / scattering or dynamic light scattering.

[0085] The content of the aqueous emulsion adhesive is preferably 35 wt% to 90 wt%, more preferably 40 wt% to 85 wt%, and even more preferably 50 wt% to 80 wt%, based on 100 wt% of the adhesive electrode. When the content of the aqueous emulsion adhesive is within the above preferred range, it is possible to impart adhesive strength and flexibility to the adhesive electrode while suppressing a decrease in conductivity.

[0086] The neutralizing agent contained in the adhesive electrode exhibits a neutralizing effect on the conductive polymer, neutralizing the conductive polymer and improving its flexibility. If the conductive polymer is, for example, PEDOT-PSS, even if PEDOT-PSS has acidic properties, the neutralizing effect can be effectively exerted on PEDOT-PSS, thereby effectively neutralizing PEDOT-PSS.

[0087] Suitable neutralizing agents include, for example, imidazole compounds.

[0088] Imidazole compounds are organic structures containing an imidazole group. The imidazole group in imidazole compounds acts as a neutralizing agent, for example, in the pH range of 3.5 to 6.5. Examples of imidazole compounds include heterocyclic amines.

[0089] Examples of heterocyclic amines include imidazole, 2-methylimidazole, 2-propylimidazole, 2-undecylimidazole, 2-phenylimidazole, N-methylimidazole, 1-(2-hydroxyethyl)imidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, and 1-cyanoethyl Examples include 2-ethyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 1-acetylimidazole, 4,5-imidazole dicarboxylic acid, 4,5-imidazole dicarboxylic acid dimethyl, benzimidazole, 2-aminobenzimidazole, 2-aminobenzimidazole-2-sulfonic acid, 2-amino-1-methylbenzimidazole, 2-hydroxybenzimidazole, and 2-(2-pyridyl)benzimidazole. Among these, imidazole is preferred. The neutralizing agent and imidazole compounds may be used individually or in combination of two or more.

[0090] The neutralizing agent content is preferably 0.5 wt% to 2.4 wt%, more preferably 0.7 wt% to 2.2 wt%, and even more preferably 1.0 wt% to 2.0 wt%, based on 100 wt% of the adhesive electrode.

[0091] The humectant contained in the adhesive electrode has the function of improving the conductivity of the adhesive electrode, as well as improving its adhesive strength and flexibility.

[0092] Examples of humectants include glycerin, ethylene glycol, propylene glycol, sorbitol, polyol compounds such as polymers thereof, N-methylpyrrolidone (NMP), dimethylformaldehyde (DMF), N-N'-dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO), and other aprotic compounds. These may be used individually or in combination of two or more. Among these, glycerin is preferred from the viewpoint of compatibility with other components.

[0093] The humectant content is preferably 2 wt% to 60 wt%, more preferably 3 wt% to 50 wt%, and even more preferably 5 wt% to 35 wt%, relative to 100 wt% of the adhesive electrode. If the humectant content is within the above preferred range, the adhesive strength of the adhesive electrode can be improved, maintaining high adhesion to the surface of the skin 2, while also reducing the storage modulus and increasing viscoelasticity, thereby suppressing the magnitude of noise generated during use. In addition, the adhesive electrode can suppress water absorption from the outside and prevent swelling.

[0094] The thickness of the electrode 20 may be any height as appropriate, for example, 10 μm to 100 μm. When the thickness of the electrode 20 is within the above preferred range, sufficient strength and flexibility can be provided to the electrode 20.

[0095] [Second layer member] As shown in Figure 4, the second layer member 30 is provided on the skin 2 side (attachment side) of the electrode 20 and serves as a support substrate for mounting the electrode 20 and the sensor unit 50, as well as forming a part of the surface that attaches to the skin 2. By mounting the sensor unit 50 on the upper surface 301 of the second layer member 30 via the electrode 20, the contact of sweat generated on the skin 2 with the sensor unit 50 can be reduced. As shown in Figures 2 and 3, the external shape of the second layer member 30 may be substantially the same as the external shape of the first base material 10.

[0096] As shown in Figure 4, the second layer member 30 has exposed portions 30a on both ends in its longitudinal direction that expose a part of the electrode 20.

[0097] The exposed portion 30a is formed in a substantially circular shape in a plan view of the biosensor 1 and may be smaller than the exposed portions 202A and 202B of the electrode 20. The shape of the exposed portion 30a in a plan view is such that the exposed portions 202A and 202B of the electrode 20 do not fall into the exposed portion 30a and parts other than the electrode 20 are not exposed. In addition to a substantially circular shape, it may be other shapes such as a substantially elliptical or substantially rectangular shape.

[0098] The size of the exposed portion 30a may be any size appropriate depending on the size and shape of the exposed portions 202A and 202B, but the exposed portion 30a is suitable for ensuring a contact area with the skin 2 and reducing the contact impedance with the skin 2, for example, 1.6 cm. 2 Preferably, it should be 3.8 cm or more. 2 It is more preferable that the above conditions are met.

[0099] The second layer member 30 may have a second base material 31, a first adhesive layer 32 provided on the upper surface 311 of the second base material 31, and a second adhesive layer 33 provided on the lower surface 312 of the second base material 31. The second base material 31, the first adhesive layer 32, and the second adhesive layer 33 may be formed to have the same shape in a plan view. The second adhesive layer 33 of the second layer member 30 and the electrode 20 form an adhesive surface to be attached to the skin 2. Depending on the area of ​​the electrode 20 and the second adhesive layer 33, and depending on the position of the adhesive surface, the waterproofness and breathability and adhesiveness can be made to differ. Therefore, depending on the area of ​​the adhesive surface of the second adhesive layer 33, the waterproofness and breathability, as well as the adhesiveness, can be made to differ.

[0100] The second layer member 30, like the first base material 10, has through holes 30b in a plan view of the biosensor 1 at positions corresponding to the protrusions 412 of the first housing 41. The through holes 30b are composed of through holes 31b in the second base material 31, through holes 32b in the first adhesive layer 32, and through holes 33b in the second adhesive layer 33. The through holes 30b only need to be large enough for the protrusions 412 of the first housing 41 to pass through.

[0101] The through-hole 30b is formed in a substantially rectangular shape in a plan view of the biosensor 1, but it is sufficient for the projection 412 to pass through, and it may be formed in other shapes such as a substantially circular or substantially elliptical shape.

[0102] Four through holes 30b are provided in the second layer member 30 so as to correspond to the projections 412, but the number of through holes 30b can be three or fewer, or six or more, as long as they are in positions corresponding to the projections 412.

[0103] (Second base material) The second base material 31 can be formed using a flexible resin having appropriate elasticity, flexibility, and toughness. Examples of materials that can be used to form the second base material 31 include polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; acrylic resins such as polyacrylic acid, polymethacrylic acid, polymethyl polyacrylate, polymethyl methacrylate (PMMA), polyethyl polymethacrylate, and polybutylene 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 resins; polyurethane resins; silicone resins; and polyvinyl chloride resins such as polyvinyl chloride and vinyl acetate copolymer resins. Among these, polyolefin resins and PET are preferably used. These thermoplastic resins have waterproof properties that do not allow moisture and water vapor to pass through (low moisture permeability). Therefore, by forming the second substrate 31 using these thermoplastic resins, when the biosensor 1 is attached to the skin 2 of a living body, it is possible to prevent sweat or water vapor generated from the skin 2 from passing through the second substrate 31 and entering the flexible substrate 51 side of the sensor part 50.

[0104] The second substrate 31 is preferably formed in a flat plate shape because the electrode 20 and sensor portion 50 are installed on its upper surface 311 side via the first adhesive layer 32.

[0105] It is preferable that the second base material 31 has a lower expansion ratio than the first base material 10. The expansion ratio is an index that indicates the degree to which the length of the second base material 31 expands or contracts between the state after expansion and the state before expansion. In this embodiment, the expansion ratio of the second base material 31 may be the degree to which it expands or contracts along the long axis of the second base material 31. When the length of the second base material 31 in its pre-expansion state is L1 and the length of the second base material 31 in its stretched state is L2, the expansion ratio of the second base material 31 is the value obtained by multiplying the ratio of the difference between L2 and L1 to L1 by 100. Stretching rate [%]=(L2-L1) / L1×100

[0106] The thickness of the second substrate 31 can be arbitrarily selected as appropriate, for example, from 1 μm to 300 μm.

[0107] The second substrate 31 has a first adhesive layer 32 on its upper surface 311 and a second adhesive layer 33 on its lower surface 312, but the first adhesive layer 32 and the second adhesive layer 33 do not necessarily have to be provided on the second substrate 31. In this case, it is preferable that the second substrate 31 has adhesive on at least one of its upper surface 311 and lower surface 312. If the second substrate 31 has adhesive on its upper surface 311 and lower surface 312, the second substrate 31 can be attached to the first substrate 10 and the electrode 20, and can also be attached to the skin 2.

[0108] (1st adhesive layer) As shown in Figure 4, the first adhesive layer 32 is provided on the upper surface 311 of the second base material 31 on the second housing 42 side (+Z axis direction), and the first base material 10, electrode 20, and sensor part 50 are bonded to it. Both ends of the first adhesive layer 32 of the second layer member 30 are provided in positions facing the opposing portions 201A and 201B of the electrode 20. This allows the opposing portions 201A and 201B of the electrode 20 and the terminals (not shown) of the sensor part 50 to be pressed and sandwiched between the first base material 10 and the second layer member 30, and enables electrical contact between the electrode 20 and the terminals (not shown) of the sensor part 50.

[0109] Since the first adhesive layer 32 can be made of the same material as the second adhesive layer 33 described later, details will be omitted.

[0110] Furthermore, the first adhesive layer 32 does not necessarily need to be provided on the second substrate 31, and may be omitted.

[0111] (2nd adhesive layer) As shown in Figure 4, the second adhesive layer 33 is provided on the lower surface 312 of the second substrate 31 on the adhesive side (-Z axis direction) and is the layer that comes into contact with the skin 2.

[0112] The second adhesive layer 33 preferably has pressure-sensitive adhesive properties. The pressure-sensitive adhesive properties of the second adhesive layer 33 allow the biosensor 1 to be easily attached to the skin 2 by pressing it against the skin 2 of a living body.

[0113] The material of the second adhesive layer 33 is not particularly limited as long as it is a pressure-sensitive adhesive material, and biocompatible materials are also available. Examples of materials for forming the second adhesive layer 33 include acrylic pressure-sensitive adhesives and silicone pressure-sensitive adhesives. Preferably, an acrylic pressure-sensitive adhesive is used.

[0114] Acrylic pressure-sensitive adhesives preferably contain an acrylic polymer as their main component. The acrylic polymer can function as a pressure-sensitive adhesive component. As the acrylic polymer, a polymer can be used that contains (meth)acrylic acid esters such as isononyl acrylate and methoxyethyl acrylate as the main component, and polymers obtained by polymerizing monomer components that can copolymerize with (meth)acrylic acid esters such as acrylic acid as optional components.

[0115] The acrylic pressure-sensitive adhesive preferably further contains a carboxylic acid ester. The carboxylic acid ester functions as a pressure-sensitive adhesive strength modifier that reduces the pressure-sensitive adhesive strength of the acrylic polymer and adjusts the pressure-sensitive adhesive strength of the second adhesive layer 33. The carboxylic acid ester can be a carboxylic acid ester that is compatible with the acrylic polymer. Examples of carboxylic acid esters include triglycerides.

[0116] Acrylic pressure-sensitive adhesives may contain a crosslinking agent as needed. The crosslinking agent is a crosslinking component that crosslinks the acrylic polymer. Examples of crosslinking agents 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 amine compounds. Among these, polyisocyanate compounds are preferred. These crosslinking agents may be used alone or in combination.

[0117] The second adhesive layer 33 preferably has excellent biocompatibility. For example, when the second adhesive layer 33 is subjected to a keratin exfoliation test, the keratin exfoliation area ratio is preferably 0% to 50%. If the keratin exfoliation area ratio is within the range of 0% to 50%, the load on the skin 2 can be suppressed even when the second adhesive layer 33 is applied to the skin 2.

[0118] The second adhesive layer 33 preferably has moisture permeability. This allows water vapor and other substances generated from the skin 2 to which the biosensor 1 is attached to escape to the first substrate 10 side through the second adhesive layer 33. Furthermore, if the first substrate 10 is formed using a foam having a cellular structure as described above, water vapor can be released to the outside of the biosensor 1 through the second adhesive layer 33. This prevents sweat or water vapor from accumulating at the interface between the skin 2 to which the biosensor 1 is attached and the second adhesive layer 33. As a result, the moisture accumulated at the interface between the skin 2 and the second adhesive layer 33 weakens the adhesive force of the second adhesive layer 33, preventing the biosensor 1 from peeling off the skin 2.

[0119] The moisture permeability of the second adhesive layer 33 is, for example, 300 g / m². 2 •day)~10000g / (m 2 It is preferable that the moisture permeability of the second adhesive layer 33 is within the above preferred range. If the second adhesive layer 33 is attached to the skin 2, sweat and other substances generated from the skin 2 can be appropriately permeated from the second adhesive layer 33 to the outside, thereby reducing the burden on the skin 2.

[0120] The thickness of the second adhesive layer 33 can be arbitrarily selected as appropriate, and is preferably between 10 μm and 300 μm. If the thickness of the second adhesive layer 33 is between 10 μm and 300 μm, the biosensor 1 can be made thinner.

[0121] [Cabinet] As shown in Figures 2 and 3, the pair of housings 40 are positioned so as to sandwich the first base material 10, the electrode 20, and the second layer member 30 between the upper surface 102 of the first base material 10 and the lower surface 302 of the second layer member 30. The pair of housings 40 includes a first housing 41 provided on the skin 2 side (attachment side) and a second housing 42 provided on the opposite side (outside) from the skin 2. The first housing 41 and the second housing 42 sandwich the first base material 10, the electrode 20, and the second layer member 30.

[0122] As shown in Figures 2 and 4, the first housing 41 is located on the outermost side (-Z axis direction) of the attachment side of the biosensor 1 and is in contact with the skin 2.

[0123] The first housing 41 has a plate-shaped base 411 and a projection 412 that protrudes from the base 411 toward the second housing 42.

[0124] The base body 411 has a flat main surface facing the second layer member 30, and may be formed in an elliptical shape in a plan view. The shape of the base body 411 in a plan view may be rectangular or the like.

[0125] The projections 412 may be provided in four positions that allow them to be inserted into the through-holes 12 of the first base material 10 and the through-holes 30b of the second layer member 30. As shown in Figure 5, the projections 412 have a height that allows them to penetrate the through-holes 12 and 30b and engage with the locking portion 421 of the second housing 42.

[0126] The projection 412 may have a flange 412a projecting from its tip edge in the circumferential direction, which is perpendicular to the height direction (Z-axis direction). The flange 412a may have a lower surface formed substantially parallel to the circumferential direction of the projection 412. The lower surface of the flange 412a is placed on the upper surface of the locking portion 421, and the projection 412 is locked to the locking portion 421 of the second housing 42, thereby enabling the first housing 41 to engage with the second housing 42.

[0127] The number of protrusions 412 is not particularly limited and may be any number as appropriate depending on the size of the base 411, etc.

[0128] As shown in Figures 2 and 4, the second housing 42 is located on the outermost side (+Z axis direction) of the biosensor 1 and is bonded to the upper surface 102 of the first substrate 10. The second housing 42 is formed in a roughly dome shape in the height direction (+Z axis direction) of Figure 1 so as to have space inside.

[0129] The second housing 42 has a recess 42a formed in a concave shape on its inner side (attachment side) facing the skin 2. On the inner side (attachment side) of the second housing 42, a storage space S for housing the sensor unit 50 is formed by the recess 42a on the inner surface of the second housing 42, the electrode 20, and the second layer member 30.

[0130] As shown in Figure 5, the second housing 42 has a locking portion 421 on the inner surface of its lower edge that engages with the projection 412. The locking portion 421 is formed on the inner surface of the lower edge of the second housing 42, protruding in a direction substantially perpendicular to the height direction (Z-axis direction), and is capable of contacting the lower surface of the flange portion 412a.

[0131] The number of locking portions 421 should be provided in accordance with the number of projections 412.

[0132] The first housing 41 and the second housing 42 press against the first base material 10, the electrode 20, and the second layer member 30 with their projections 412 locked to the locking portion 421. In this embodiment, the first housing 41 and the second housing 42 are locked together by the projection 412 of the first housing 41 and the locking portion 421 of the second housing 42, but other configurations are also acceptable as long as the first housing 41 and the second housing 42 can be locked together.

[0133] The material used to form the housing 40 may be a material with insulating properties and high strength, or a flexible material. By forming the housing 40 using the above-mentioned flexible material, the hardness of the housing 40 can be increased, thereby suppressing a decrease in the waveform accuracy of the measured biological signal when measuring the biological signal. In addition, the sensor unit 50, which is placed in the storage space S formed inside the second housing 42, is protected, and impacts applied to the biological sensor 1 from the top or bottom are absorbed, mitigating the impact applied to the sensor unit 50.

[0134] Examples of materials with insulating properties and high strength include polyester (PE) resins, polyacrylonitrile (PAN) resins, acrylic (PMMA) resins, polyimide (PE) resins, polycarbonate (PC) resins, polybutadiene (PBR) resins, polyethersulfone (PES) resins, polyetheretherketone (PEEK) resins, polysulfone (PS) resins, polyphenylene sulfide (PPS) resins, polyamide (PA) resins, polysiloxane resins, polystyrene (PS) resins, polyamideimide (PAI) resins, polyurethane (PU) resins, vinyl chloride (PVC) resins, polyvinylidene chloride (PVDC) resins, polypropylene (PP) resins, polytetrafluoroethylene (PTFE) resins, ABS resins, and polyphenylene oxide (PPO) resins. Among these, polycarbonate (PC) resins, polystyrene (PS) resins, and ABS resins are particularly noteworthy. These may be used individually or in combination of two or more types.

[0135] Flexible materials can include thermoplastic resins such as acrylic resins, polyurethane resins, polystyrene resins, polyolefin resins, silicone resins, vinyl chloride resins, and polyester resins, as well as thermoplastic elastomers and crosslinked rubbers.

[0136] Examples of thermoplastic elastomers include polyurethane-based thermoplastic elastomers, polystyrene-based thermoplastic elastomers, polyolefin-based thermoplastic elastomers, polyester-based thermoplastic elastomers, polyvinyl chloride-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, nitrile-based thermoplastic elastomers, nylon-based thermoplastic elastomers, fluororubber-based thermoplastic elastomers, polybutadiene-based thermoplastic elastomers, ethylene vinyl acetate-based thermoplastic elastomers, chlorinated polyethylene-based thermoplastic elastomers, styrene-butadiene block copolymers or their hydrogenated derivatives, styrene-isoprene block copolymers or their hydrogenated derivatives, and the like. These may be used individually or in combination of two or more.

[0137] Examples of crosslinked rubbers include silicone rubber, fluororubber, urethane rubber, natural rubber, acrylic rubber, butadiene rubber, isoprene rubber, styrene-butadiene copolymer rubber, nitrile rubber, hydrogenated nitrile rubber, chloroprene rubber, ethylene-propylene copolymer rubber, chlorinated polyethylene rubber, chlorosulfonated polyethylene rubber, butyl rubber, and halogenated butyl rubber. The housing 40 may also be formed by laminating the above-mentioned flexible material onto the surface of a base resin such as polyethylene terephthalate (PET) as a support. By forming the housing 40 using the above-mentioned flexible material, the sensor part 50, which is placed in the storage space S formed inside the second housing 42, is protected, and the impact applied to the biosensor 1 from above is absorbed, mitigating the impact on the sensor part 50.

[0138] The thickness of the enclosure 40 can be designed as appropriate, for example, 1.5 mm to 3 mm.

[0139] The hardness of the second housing 42 can be designed to any appropriate size, for example, preferably between 10 and 40. The upper limit of the hardness is more preferably 30 or less. If the hardness of the second housing 42 is within the above preferred range, when the skin 2 is stretched due to body movement, the first base material 10, electrode 20, and second layer member 30 can be easily deformed in accordance with the movement of the skin 2 without being affected by the second housing 42. Note that hardness refers to Shore A hardness. In this specification, Shore A hardness refers to the hardness measured according to ISO 7619 (JIS K 6253-3:2012). As described in JIS K 6253-3:2012 "Vulcanized rubber and thermoplastic rubber - Method for determining hardness - Part 3: Durometer hardness", the measured value of Shore A hardness obtained by preparing a sheet sample of the second housing 42 can be taken as the Shore A hardness of the second housing 42.

[0140] [Sensor unit] As shown in Figures 2 and 3, the sensor unit 50 includes a flexible substrate 51, a sensor body 52, and a battery 53. The sensor unit 50 may have a connection portion (not shown) on the flexible substrate 51 that connects to the sensor body 52.

[0141] The flexible substrate 51 is a resin substrate on which various components for acquiring biological information are mounted, and the sensor body 52 and battery 53 may be placed on the flexible substrate 51.

[0142] The sensor body 52 acquires biological information and may have, for example, a component mounting section which is a control unit.

[0143] The component mounting section may include various components mounted on the flexible substrate 51, such as a CPU and integrated circuit that acquire biological information and process biological signals acquired from the body to generate biological signal data, a switch to activate the biological sensor 1, a flash memory for storing biological signals, and a light-emitting element. The component mounting section may transmit via wired or wireless connection to external devices such as an operation confirmation device for checking initial operation and a reading device for reading biological information from the biological sensor 1. Component mounting sections not shown may be powered by electricity supplied from a battery 53.

[0144] The unillustrated connection portion may, for example, include wiring (not shown) connected to the sensor body 52 in the longitudinal direction (Y-axis direction) of the sensor body 52, and a terminal portion (not shown) provided at one end (Y-axis direction) of the wiring (not shown) and connected to the electrode 20.

[0145] The battery 53 is installed on the flexible circuit board 51 and supplies power to an integrated circuit, etc., mounted on a component mounting section (not shown) of the sensor body 52. ​​The battery 53 may be a known battery. For example, a coin cell battery such as a CR2025 may be used as the battery 53.

[0146] As shown in Figures 2 and 3, when the biosensor 1 is not in use, it is preferable to attach the release liner 60 to the surfaces of the electrodes 20, second substrate 31, and second housing 42 that come into contact with the skin 2, in order to protect the electrodes 20, second substrate 31, and second housing 42 until use. When in use, the release liner 60 is peeled off from the electrodes 20, second substrate 31, and second housing 42, and the surface of the biosensor 1 is attached to the skin 2. By keeping the release liner 60 attached to the surface, the adhesive strength of the electrodes 20 and second layer member 30 can be maintained even if the biosensor 1 is stored for a long period of time. Therefore, when in use, the release liner 60 is peeled off from the electrodes 20, second substrate 31, and second housing 42, ensuring that the surface is securely attached to the skin 2.

[0147] The method for manufacturing the biosensor 1 is not particularly limited and can be manufactured using any method as appropriate. An example of a method for manufacturing the biosensor 1 will be described below.

[0148] As shown in Figure 2, a first substrate 10, an electrode 20, a second layer member 30, a pair of housings 40, and a sensor unit 50 are prepared. Each of these components is not particularly limited as long as it can be manufactured using any method that is suitable for manufacturing them.

[0149] After preparing each component that makes up the biosensor 1 shown in Figure 2, the sensor unit 50 is placed on the second layer member 30. Then, the second layer member 30, the electrode 20, and the first base material 10 are stacked in that order from the second layer member 30 side toward the first base material 10 side, and sandwiched between a pair of housings 40. This results in the biosensor 1 shown in Figure 1.

[0150] Figure 6 is an explanatory diagram showing the biosensor 1 from Figure 1 attached to the chest of subject P. As shown in Figure 6, for example, the biosensor 1 is attached to the skin of subject P with its longitudinal direction (Y-axis direction) aligned with the sternum of subject P, with one electrode 20A on the upper side and the other electrode 20B on the lower side. The biosensor 1 is attached to the skin of subject P by the second adhesive layer 33 from Figure 4, and with the electrodes 20 pressed against the skin of subject P, it acquires biological signals such as electrocardiogram signals from subject P via the electrodes 20. The biosensor 1 stores the acquired biological signal data in a non-volatile memory such as a flash memory mounted on a component mounting section (not shown).

[0151] Thus, the biosensor 1 comprises a first substrate 10, electrodes 20, and a second layer member 30. The first substrate 10 has an exposed portion 13, and the second layer member 30 has an exposed portion 30a. As a result, the biosensor 1 can expose a portion of the electrodes 20 to both the sensor portion 50 side and the skin 2 side. The upper surfaces of the opposing portions 201A and 201B of the electrodes 20 can be brought into contact with the sensor portion 50 via the exposed portion 13 of the first substrate 10, and the lower surfaces of the exposed portions 202A and 202B of the electrodes 20 can be brought into contact with the skin 2 via the exposed portion 30a of the second layer member 30. The biosensor 1 can detect biological information from the skin 2 using the exposed portions 202A and 202B of the electrodes 20 exposed from the exposed portion 30a, and transmit the biological information to the sensor portion 50 using the opposing portions 201A and 201B of the electrodes 20 exposed from the exposed portion 13.

[0152] The biosensor 1 utilizes both the upper and lower surfaces of the electrode 20, exposing a portion of the electrode 20 to contact the sensor unit 50 and the skin 2. This allows the electrode 20 alone to perform the roles of detecting biological information and transmitting it to the sensor unit 50. Therefore, the biosensor 1 can acquire biological information with a simple configuration.

[0153] The biosensor 1 has a first substrate 10 on the side opposite the skin 2 to the electrode 20, and the exposed portion 13 of the first substrate 10 can be positioned opposite the sensor portion 50. This allows the biosensor 1 to reliably bring the electrode 20 exposed from the exposed portion 13 into contact with the sensor portion 50, thereby reliably transmitting biological information to the sensor portion 50.

[0154] The biosensor 1 is equipped with a second layer member 30 on the skin 2 side relative to the electrode 20, and the exposed portion 30a of the second layer member 30 can be positioned facing the skin 2. As a result, the biosensor 1 can bring the electrode 20 exposed from the exposed portion 30a into contact with the skin 2, thereby reliably detecting biological information.

[0155] The biosensor 1 comprises a first base material 10 and a second layer member 30. The second base material 31 of the second layer member 30 can have a lower expansion ratio than the first base material 10. As a result, the second base material 31 can have appropriate rigidity, which prevents the second layer member 30 from deforming excessively when the surface of the skin 2 deforms due to body movement, thereby preventing disconnection of the electrodes 20. Therefore, the biosensor 1 can maintain its adherence even when the surface of the skin 2 deforms due to body movement, and can stably transmit acquired biological information to the sensor unit 50.

[0156] The biosensor 1 can have a second substrate 31 that is thinner than the first substrate 10. By making the second substrate 31, which is located on the skin 2 side, thinner, the electrode 20 can more easily come into contact with the skin 2 from its exposed portion 30a. Therefore, the biosensor 1 can more easily acquire biological information from the skin 2 at the exposed portions 202A and 202B of the electrode 20.

[0157] The biosensor 1 can have an exposed portion 13 on the first substrate 10 positioned opposite the sensor portion 50, and an exposed portion 30a on the second layer member 30 positioned opposite the skin 2. This ensures that the biosensor 1 makes reliable contact with the skin 2 via the exposed portion 13, and that the electrode 20 makes reliable contact with the sensor portion 50 via the exposed portion 30a, thereby ensuring reliable detection of biological signals and transmission of biological information to the sensor portion 50.

[0158] The biosensor 1 has a first adhesive layer 32 on the upper surface 311 of the second substrate 31 and a second adhesive layer 33 on the lower surface 312 of the second substrate 31, so that adhesive layers can be provided on both sides of the second substrate 31. This allows the biosensor 1 to improve the adhesion between the second layer member 30 and the first substrate 10 and the electrode 20. In addition, the second layer member 30 can be more firmly fixed by a pair of housings 40. As a result, the biosensor 1 can suppress displacement of the electrode 20 and maintain a stronger connection between the electrode 20 and the sensor body 52, so that biological signals can be measured stably.

[0159] The biosensor 1 can have a second substrate 31 that, in a plan view of the biosensor 1, has an external shape corresponding to the first substrate 10. As a result, the biosensor 1 can have a first adhesive layer 32 applied to the entire upper surface 311 of the second substrate 31, so that the entire upper surface 301 of the second layer member 30 can be attached to and joined to the first substrate 10. Since the interface between the first substrate 10 and the second layer member 30 is formed only on the side surface, external water is less likely to remain on the side surface of the first substrate 10 and the second layer member 30. Therefore, compared to the case where the interface between the first substrate 10 and the second layer member 30 is formed on the upper surface 301 of the second layer member 30, external water is less likely to penetrate from the interface between the first substrate 10 and the second layer member 30. Thus, the biosensor 1 can improve the waterproofness of the housing space S inside the biosensor 1.

[0160] The biosensor 1 comprises a pair of housings 40, the first housing 41 having a projection 412 and the second housing 42 having a locking portion 421. The biosensor 1 can fix the first base material 10 by the first housing 41 and the second housing 42 with the projection 412 locked to the locking portion 421. As a result, the biosensor 1 can prevent gaps from forming between the first base material 10 and the second housing 42, thereby maintaining a sealed state of the housing space S inside the biosensor 1 and suppressing the intrusion of moisture from the outside. Therefore, the biosensor 1 can seal the housing space S inside the biosensor 1 with a simple configuration and exhibit waterproofness.

[0161] The biosensor 1 can have a projection 412 on the first housing 41 and a locking portion 421 on the second housing 42 of a pair of housings 40. The biosensor 1 can be secured to the first base material 10 by passing the projection 412 through the through hole 12 in the first base material 10 and the through hole 30b in the second layer member 30, and the projection 412 can be locked to the locking portion 421. As a result, the biosensor 1 can be fixed while suppressing the formation of a gap between the first base material 10 and the second housing 42, thereby maintaining a sealed state of the housing space S inside the biosensor 1 and suppressing the intrusion of moisture from the outside. Therefore, the biosensor 1 can exhibit waterproofness because the housing space S inside the biosensor 1 can be sealed with a simple configuration.

[0162] The biosensor 1 can have its first substrate 10 made of a porous material. This allows the first substrate 10 to be made more flexible. As a result, when the surface of the skin 2 deforms due to body movement or the like, the biosensor 1 can easily deform the first substrate 10 in accordance with the deformation of the electrodes 20 and the second substrate 31. Therefore, the biosensor 1 can improve its ability to conform to the surface of the skin 2 and improve its adherence to the skin 2.

[0163] The biosensor 1 has a first substrate 10 whose shape in plan view is formed with both ends in the longitudinal direction being arc-shaped. As a result, even if the surface of the skin 2 deforms in any direction due to body movement, the biosensor 1 can deform substantially the same way in all directions, and gaps between the skin 2 and the attachment surface of the biosensor 1 can be suppressed. Furthermore, even if the second layer member 30 deforms in accordance with the skin 2, the biosensor 1 can prevent sharp corners from forming on the outer shape of the second layer member 30 and piercing the skin 2, thereby reducing pain to the subject.

[0164] The biosensor 1 can be formed by including a conductive polymer in the electrode 20. This is because if the electrode 20 is formed using metal or the like, it may cause metal allergies or other problems in the subject, which can be burdensome for the subject. By forming the electrode 20 of the biosensor 1 with a conductive polymer, irritation to the subject's skin 2 is suppressed, and the burden on the subject can be reduced.

[0165] The biosensor 1 can have adhesive properties on its electrode 20. This allows the biosensor 1 to enhance the adhesion of the electrode 20 to the first substrate 10 and the skin 2 by attaching the electrode 20 to the skin 2 side of the first substrate 10, thus firmly fixing the electrode 20 sandwiched between the first substrate 10 and the second layer member 30. Furthermore, the biosensor 1 can stably maintain the state in which the electrode 20 is attached to the skin 2, and can suppress displacement of the electrode 20 even when body movement occurs. As a result, the biosensor 1 can suppress the generation of noise when measuring biological signals and can be attached to the skin 2 more stably. Thus, the biosensor 1 can improve the detection accuracy of biological signals during use while maintaining adhesion to the skin 2.

[0166] The biosensor 1 can have its second housing 42 formed in a dome shape. This makes it easier for the second housing 42 to form an internal space, thereby increasing the size of the storage space S formed by the recess 42a of the second housing 42 and the second layer member 30. As a result, the biosensor 1 can easily accommodate the sensor unit 50 within the storage space S, making it easier to house the sensor unit 50 within the storage space S.

[0167] As described above, the biosensor 1 can stably measure biological information from the skin 2 for a long period of time during use, and therefore can be effectively used as an adhesive-type biosensor that is attached to human skin 2, etc. The biosensor 1 can be suitably used, for example, in healthcare wearable devices that are attached to the skin of a living person and require high sensitivity for detecting electrocardiograms and a high level of noise suppression effect in electrocardiograms.

[0168] In this embodiment, the biosensor 1 has a first substrate 10 and a second layer member 30 as its base material, but it may have only one of these. The biosensor 1 may have only the first substrate 10 as its base material, as shown in Figure 7, or it may have only the second layer member 30 as its base material, as shown in Figure 8.

[0169] In this embodiment, the first base material 10 may have an opening (not shown) at a position facing the pair of housings 40. The opening may be formed such that, in a plan view of the biosensor 1, it is larger than or equal to the outer shape of the sensor portion 50 at a position corresponding to the housing 40. By having the opening, the first base material 10 can house the sensor portion 50 in the storage space S formed by the recess 42a on the inner surface of the second housing 42, the opening, and the second layer member 30, without being obstructed by the first base material 10, and can also connect the sensor portion 50 to the electrode 20.

[0170] In this embodiment, the first housing 41 has a projection 412 and the second housing 42 has a locking portion 421. However, the first housing 41 may have a locking portion and the second housing 42 may have a projection, and the projection of the second housing 42 may be locked to the locking portion of the first housing 41.

[0171] In this embodiment, the first housing 41 and the second housing 42 may each have a projection and a locking portion that engages with one of the projections. That is, the first housing 41 may have a projection 412 and a locking portion that engages with the projection of the second housing 42, and the second housing 42 may have a projection and a locking portion 421 that engages with the projection 412 of the first housing 41.

[0172] In this embodiment, the second layer member 30 is composed of a second base material 31, a first adhesive layer 32, and a second adhesive layer 33. However, if the second base material 31 has an adhesive on at least one surface, at least one of the first adhesive layer 32 and the second adhesive layer 33 may be omitted.

[0173] As described above, embodiments have been explained, but these embodiments are presented as examples only, and the present invention is not limited by these embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, and modifications are possible without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents.

[0174] The embodiments of the present invention are, for example, as follows. <1> A biosensor that is attached to a living body, An electrode provided on the biological side of the sensor body that acquires biological information, A substrate provided on the side of the electrode that is on the side of the living body or the side that is on the opposite side of the living body, having an exposed portion that exposes a part of the electrode, Equipped with, The electrode is a biosensor that contacts the sensor body or the living body via the exposed portion. <2> The substrate has a first substrate provided on the side opposite to the biological tissue with respect to the electrode, The exposed portion is provided at a position opposite to the sensor body. <1> The biosensor described above. <3> The substrate has a second substrate provided on the biological side relative to the electrode, The exposed portion is provided in a position facing the living body. <1> The biosensor described above. <4> The aforementioned substrate is A first substrate is provided on the side opposite to the biological tissue relative to the electrode, A second substrate provided on the biological side relative to the electrode, It has, The second substrate has a lower expansion ratio than the first substrate. <1> The biosensor described above. <5> The thickness of the second substrate is thinner than the thickness of the first substrate. <4> The biosensor described above. <6> The exposed portion provided on the first substrate is provided at a position facing the sensor body, The exposed portion provided on the second substrate is positioned facing the living body. <4> The biosensor described above. <7> The second substrate has an adhesive on at least one surface. <3> or <4> The biosensor described above. <8> The second substrate has an adhesive layer on at least one of the surfaces different from the biological side and the biological side. <3> or <4> The biosensor described above. <9> The second substrate has an external shape corresponding to the first substrate in a plan view of the biosensor. <4> ~ <8> A biosensor described in any one of the following. <10> The system comprises a pair of housings arranged to sandwich the electrode and the substrate. <1> ~ <9> A biosensor described in any one of the following. <11> Of the pair of housings, one or both of the first housing, which is provided on the biological side relative to the substrate, and the second housing, which is provided on the opposite side of the biological side relative to the substrate, have projections that protrude toward the substrate and are inserted into through holes provided in the substrate. One or both of the first housing and the second housing have a locking portion that engages with the projection. <10> The biosensor described above. <12> The substrate is a porous body containing closed cells. <1> ~ <11> A biosensor described in any one of the following. <13> In a plan view, the substrate has both ends in the longitudinal direction formed in an arc shape. <1> ~ <12> A biosensor described in any one of the following. <14> The electrode contains a conductive polymer. <1> ~ <13> A biosensor described in any one of the following. <15> The electrode has adhesive properties <1> ~ <14> A biosensor described in any one of the following. [Explanation of Symbols]

[0175] 1. Biosensor 2 skin 10 First base material 12, 30b, 31b, 32b, 33b, 204A, 204B through hole 13, 30a Exposed part 20, 20A, 20B electrode 30 Second layer member 31 Second base material 32 1st adhesive layer 33 Second adhesive layer 40 cabinets 41. First cabinet 412 Protrusion 42 Second cabinet 42a depression 421 Locking part 50 Sensor section 52 Sensor body S Containment space

Claims

1. A biosensor that is attached to a living body, An electrode provided on the biological side of the sensor body that acquires biological information, A substrate provided on the side of the electrode that is on the side of the living body or the side that is on the opposite side of the living body, having an exposed portion that exposes a part of the electrode, Equipped with, The electrode is a biosensor that contacts the sensor body or the living body via the exposed portion.

2. The substrate has a first substrate provided on the side opposite to the biological tissue with respect to the electrode, The biosensor according to claim 1, wherein the exposed portion is provided at a position opposite to the sensor body.

3. The substrate has a second substrate provided on the biological side relative to the electrode, The biosensor according to claim 1, wherein the exposed portion is provided at a position facing the living body.

4. The aforementioned substrate is A first substrate is provided on the side opposite to the biological tissue with respect to the electrode, A second substrate provided on the biological side relative to the electrode, It has, The biosensor according to claim 1, wherein the second substrate has a lower expansion ratio than the first substrate.

5. The biosensor according to claim 4, wherein the thickness of the second substrate is thinner than the thickness of the first substrate.

6. The exposed portion provided on the first substrate is provided at a position facing the sensor body, The biosensor according to claim 4, wherein the exposed portion provided on the second substrate is provided at a position facing the living body.

7. The biosensor according to claim 3 or 4, wherein the second substrate has an adhesive on at least one surface.

8. The biosensor according to claim 3 or 4, wherein the second substrate has an adhesive layer on at least one of the surfaces different from the biological side and the biological side.

9. The biosensor according to claim 4, wherein the second substrate has an external shape corresponding to the first substrate in a plan view of the biosensor.

10. The biosensor according to claim 1, comprising a pair of housings arranged to sandwich the electrode and the substrate.

11. Of the pair of housings, one or both of the first housing, which is provided on the biological side relative to the substrate, and the second housing, which is provided on the opposite side of the biological side relative to the substrate, have projections that protrude toward the substrate and are inserted into through holes provided in the substrate. The biosensor according to claim 10, wherein one or both of the first housing and the second housing have a locking portion for locking the projection.

12. The biosensor according to claim 1, wherein the substrate is a porous body containing closed cells.

13. The biosensor according to claim 1, wherein the substrate has both ends in the longitudinal direction formed in an arc shape when viewed in plan.

14. The biosensor according to claim 1, wherein the electrode comprises a conductive polymer.

15. The biosensor according to claim 1, wherein the electrode is adhesive.

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