JP6814899B2 - Biosensor - Google Patents

Description

The present invention relates to a biosensor.

In medical institutions such as hospitals and clinics, nursing care facilities, homes, and the like, biosensors that measure biometric information such as electrocardiogram, pulse wave, electroencephalogram, and myoelectricity are used. The biosensor includes a bioelectrode that comes into contact with the living body and acquires biometric information of the subject. When measuring biometric information, a biosensor is attached to the subject's skin and the bioelectrode is brought into contact with the subject's skin. Biometric information is measured by acquiring electrical signals related to biological information with bioelectrodes.

As such a biosensor, for example, a polymer layer having an electrode on one surface is provided, and dimethylvinyl-terminated dimethylsiloxane (DSDT) and tetramethyltetravinylcyclotetrasiloxane (TTC) are used as the polymer layer in a predetermined ratio. A biocompatible polymer substrate using a polymerized polymer substrate is disclosed (see, for example, Patent Document 1). In the biocompatible polymer substrate, a polymer layer is attached to human skin, electrodes detect myocardial voltage signals from human skin, and a data acquisition module receives and records myocardial voltage signals. ..

Japanese Unexamined Patent Publication No. 2012-10978

However, since the biocompatible polymer substrate of Patent Document 1 is used by being attached to the skin of the subject with a polymer layer, the biocompatible polymer substrate may be bent in the thickness direction or the skin of the subject may move. The biosensor may be pulled in the plane direction. Therefore, in the conventional biocompatible polymer substrate, the electrode may be peeled off from the living body or the polymer layer. Further, the electrode may be peeled off from the living body or the polymer layer, so that stable conductivity may not be obtained.

One aspect of the present invention is to provide a biological sensor capable of having conductivity while suppressing peeling between an adhesive layer installed on one surface of an electrode and a biological surface on which the electrode is installed. ..

One aspect of the biological sensor according to the present invention is a pressure-sensitive adhesive layer for sticking to the biological surface, an electrode arranged so as to be in contact with the biological surface on the sticking side of the pressure-sensitive adhesive layer to the biological surface. An electronic device that processes a biological signal acquired via the electrode and a circuit unit that connects the electrode and the electronic device are provided , and the electrode is connected to the circuit unit on the side of being attached to the biological surface. have a that connecting surfaces, and to have a one or more holes penetrating in the thickness direction of the electrode on the connection surface.

One aspect of the biological sensor according to the present invention can have conductivity while suppressing peeling between the adhesive layer installed on one surface of the electrode and the biological surface on which the electrode is installed.

It is an exploded view which shows the stick-on type biosensor. It is a figure which shows the cross section of the completed state corresponding to the cross section of AA of FIG. It is a perspective view of the electrode which concerns on one Embodiment. It is a partially enlarged plan view of an electrode. It is a figure which shows the circuit structure of the stick-on type biosensor. It is sectional drawing which shows an example of another form of a stick-on type biosensor in a completed state corresponding to the cross-sectional view taken along the line AA of FIG. It is a perspective view which shows an example of another structure of an electrode. It is a perspective view which shows an example of another structure of an electrode. It is a figure which shows the relationship between the aperture ratio and the peeling adhesive force. It is a figure which shows the relationship between the number of holes and the peeling adhesive force. It is a figure which shows the relationship between the number of holes in Examples 2-1 to 2-4 and the expansion / contraction ratio at the time of breaking.

Hereinafter, embodiments of the present invention will be described in detail. In addition, in order to facilitate understanding of the description, the same components are designated by the same reference numerals in each drawing, and duplicate description will be omitted. In addition, the scale of each member in the drawing may differ from the actual scale. In the present specification, a three-dimensional Cartesian coordinate system in the three-axis directions (X-axis direction, Y-axis direction, Z-axis direction) is used, the coordinates on the main surface of the electrode are the X-axis direction and the Y-axis direction, and the height direction ( The thickness direction) is the Z-axis direction. The direction from the bottom to the top of the electrode is the + Z-axis direction, and the opposite direction is the -Z-axis direction. In the following description, for convenience of explanation, the + Z-axis direction is referred to as an upper side or an upper side, and the −Z axis direction is referred to as a lower side or a lower side, but does not represent a universal hierarchical relationship. Unless otherwise specified, the tilde "~" indicating a numerical range in the present specification means that the numerical values described before and after the tilde are included as the lower limit value and the upper limit value.

<Biosensor>
A biosensor according to an embodiment will be described. In the present embodiment, as an example, a case where the stick-on biosensor is brought into contact with a living body to measure biological information will be described. The living body means a human body and animals such as cows, horses, pigs, chickens, dogs and cats. The biosensor is attached to a part of the living body (for example, skin, scalp, forehead, etc.). The biosensor can be suitably used for a living body, particularly for the human body.

FIG. 1 is an exploded view showing a stick-on biosensor 100 according to an embodiment. FIG. 2 is a diagram showing a cross section in a completed state corresponding to the cross section taken along the line AA of FIG. As shown in FIGS. 1 and 2, the stick-on biosensor 100 according to the embodiment has, as main components, a pressure-sensitive adhesive layer 110, a base material layer 120, a circuit unit 130, a substrate 135, a probe 140, and fixed. Includes tape 145, electronics 150, battery 160 and cover 170. Hereinafter, each member constituting the stick-on biosensor 100 will be described.

The stick-on biosensor 100 is a sheet-like member having a substantially elliptical shape in a plan view. In the stick-on type biosensor 100, the upper surface side opposite to the lower surface (the surface on the −Z direction side) to be attached to the skin 200 of the living body is covered with the cover 170. The lower surface of the stick-on biosensor 100 is a stick-on surface.

The circuit unit 130 and the substrate 135 are mounted on the upper surface of the substrate layer 120. Further, the probe 140 is provided in a state of being embedded in the pressure-sensitive adhesive layer 110A so as to be exposed from the lower surface 112 of the pressure-sensitive adhesive layer 110. The lower surface 112 is a sticking surface of the sticking type biosensor 100.

The pressure-sensitive adhesive layer 110 is a flat-plate adhesive layer. The pressure-sensitive adhesive layer 110 has a longitudinal direction in the X-axis direction and a lateral direction in the Y-axis direction. The pressure-sensitive adhesive layer 110 is supported by the base material layer 120 and is attached to the lower surface 121 of the base material layer 120.

As shown in FIG. 2, the pressure-sensitive adhesive layer 110 has an upper surface 111 and a lower surface 112. The upper surface 111 and the lower surface 112 are flat surfaces. The pressure-sensitive adhesive layer 110 is a layer in which the stick-on biosensor 100 comes into contact with the living body. Since the lower surface 112 has pressure-sensitive adhesiveness, it can be attached to the skin 200 of a living body. The lower surface 112 is the lower surface of the stickable biological sensor 100, and can be attached to the surface of the living body such as the skin 200.

The material of the pressure-sensitive adhesive layer 110 is not particularly limited as long as it has pressure-sensitive adhesiveness, and examples thereof include materials having biocompatibility. Examples of the material of the pressure-sensitive adhesive layer 110 include an acrylic pressure-sensitive adhesive and a silicone-based pressure-sensitive adhesive. Acrylic pressure-sensitive adhesives are preferable.

The acrylic pressure-sensitive adhesive contains an acrylic polymer as a main component.

Acrylic polymer is a pressure sensitive adhesive component. The acrylic polymer contains a (meth) acrylic acid ester such as isononyl acrylate and methoxyethyl acrylate as a main component, and a monomer component copolymerizing with a (meth) acrylic acid ester such as acrylic acid as an optional component. A polymer obtained by polymerizing the above can be used. The content of the main component in the monomer component is 70% by mass to 99% by mass, and the content of the optional component in the monomer component is 1% by mass to 30% by mass. As the acrylic polymer, for example, the (meth) acrylic acid ester-based polymer described in JP-A-2003-342541 can be used.

The acrylic pressure-sensitive adhesive preferably further contains a carboxylic acid ester.

The carboxylic acid ester contained in the acrylic pressure-sensitive adhesive is a pressure-sensitive adhesive force adjusting agent that reduces the pressure-sensitive adhesive force of the acrylic polymer and adjusts the pressure-sensitive adhesive force of the pressure-sensitive adhesive layer 110. The carboxylic acid ester is a carboxylic acid ester that is compatible with the acrylic polymer.

Specifically, the carboxylic acid ester is, for example, the trifatty acid glyceryl.

The content of the carboxylic acid ester is preferably 30 parts by mass to 100 parts by mass, and more preferably 50 parts by mass to 70 parts by mass or less with respect to 100 parts by mass of the acrylic polymer.

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

The content of the cross-linking agent is preferably, for example, 0.001 part by mass to 10 parts by mass, and more preferably 0.01 part by mass to 1 part by mass with respect to 100 parts by mass of the acrylic polymer.

The pressure-sensitive adhesive layer 110 preferably has excellent biocompatibility. For example, when the pressure-sensitive adhesive layer 110 is subjected to a keratin peeling test, the keratin peeling area ratio is preferably 0% to 50%, more preferably 1% to 15%. When the keratin exfoliation area ratio is within the range of 0% to 50%, the load on the skin 200 (see FIG. 2) can be suppressed even if the pressure-sensitive adhesive layer 110 is attached to the skin 200 (see FIG. 27). The keratin exfoliation test is measured by the method described in JP-A-2004-83425.

The moisture permeability of the pressure-sensitive adhesive layer 110 is preferably 300 (g / m ² / day) or more, more preferably 600 (g / m ² / day) or more, and 1000 (g / m ² / day) or more. Day) or more is more preferable. If the moisture permeability of the pressure-sensitive adhesive layer 110 is 300 (g / m ² / day) or more, even if the pressure-sensitive adhesive layer 110 is attached to the skin 200 of a living body (see FIG. 2), the skin 200 (FIG. 2). The load of (see) can be suppressed.

The pressure-sensitive adhesive layer 110 satisfies at least one of the requirements that the keratin peeling area ratio in the keratin peeling test is 50% or less and the moisture permeability is 300 (g / m ² / day) or more. The pressure-sensitive adhesive layer 110 is biocompatible. It is more preferable that the material of the pressure-sensitive adhesive layer 110 satisfies both of the above requirements. As a result, the pressure-sensitive adhesive layer 110 is more stable and has high biocompatibility.

The thickness between the upper surface 111 and the lower surface 112 of the pressure-sensitive adhesive layer 110 is preferably 10 μm to 300 μm. When the thickness of the pressure-sensitive adhesive layer 110 is 10 μm to 95 μm, the stick-on biosensor 100 can be made thinner, and in particular, the area other than the electronic device 150 in the stick-on biosensor 100 can be made thinner.

The base material layer 120 is a support layer that supports the pressure-sensitive adhesive layer 110, and the pressure-sensitive adhesive layer 110 is adhered to the lower surface 121 of the base material layer 120. The circuit unit 130 and the substrate 135 are arranged on the upper surface side of the base material layer 120.

The base material layer 120 is a flat plate-shaped (sheet-shaped) member made of an insulator. The shape of the base material layer 120 in a plan view is the same as the shape of the pressure-sensitive adhesive layer 110 in a plan view, and they are aligned and overlapped in a plan view.

The base material layer 120 has a lower surface 121 and an upper surface 122. The lower surface 121 and the upper surface 122 are flat surfaces. The lower surface 121 is in contact with the upper surface 111 of the pressure-sensitive adhesive layer 110 (pressure-sensitive adhesion). The base material layer 120 may be made of a flexible resin having appropriate elasticity, flexibility and toughness. For example, a polyurethane resin, a silicone resin, an acrylic resin, a polystyrene resin, or a vinyl chloride resin. , And a thermoplastic resin such as a polyester resin.

The thickness of the base material layer 120 is preferably 1 μm to 300 μm, more preferably 5 μm to 100 μm, and even more preferably 10 μm to 50 μm.

The circuit unit 130 has a wiring 131, a frame 132, and a substrate 133, and connects the probe 140 and the electronic device 150. The stick-on biosensor 100 includes two such circuit units 130. The wiring 131 and the frame 132 are provided on the upper surface of the substrate 133 and are integrally formed. The wiring 131 connects the frame 132 with the electronic device 150 and the battery 160. Further, the circuit unit 130 is connected to the probe 140 on the side opposite to the side where the skin 200 is attached to the surface (in the + Z axis direction). The connection portion of the circuit portion 130 with the probe 140 is arranged on the side (+ Z axis direction) opposite to the side where the probe 140 is attached to the surface of the skin 200.

The wiring 131 and the frame 132 can be made of copper, nickel, gold, an alloy thereof, or the like. The thickness of the wiring 131 and the frame 132 is preferably 0.1 μm to 100 μm, more preferably 1 μm to 50 μm, and even more preferably 5 μm to 30 μm.

The two circuit units 130 are provided corresponding to the two through holes 113 and 123 of the pressure-sensitive adhesive layer 110 and the base material layer 120, respectively. The wiring 131 is connected to the electronic device 150 and the terminal 135A for the battery 160 via the wiring of the substrate 135. The frame 132 is a rectangular annular conductive member larger than the opening of the through hole 123 of the base material layer 120.

The substrate 133 has the same shape as the wiring 131 and the frame 132 in a plan view. The portion of the substrate 133 where the frame 132 is provided has a rectangular annular shape larger than the opening of the through hole 123 of the base material layer 120. The frame 132 and the rectangular annular portion of the substrate 133 on which the frame 132 is provided are provided so as to surround the through hole 123 on the upper surface of the base material layer 120. The substrate 133 may be made of an insulator material, and for example, a substrate or a film made of polyimide or the like can be used. Since the base material layer 120 has adhesiveness (tack), the substrate 133 is fixed to the upper surface of the base material layer 120.

The substrate 135 is a substrate made of an insulator material on which the electronic device 150 and the battery 160 are mounted, and is provided on the upper surface 122 of the base material layer 120. The substrate 135 is fixed by the tack (adhesiveness) of the substrate layer. As the substrate 135, as an example, a substrate or a film made of polyimide or the like can be used. Wiring and terminals 135A for the battery 160 are provided on the upper surface of the substrate 135. The wiring of the board 135 is connected to the electronic device 150 and the terminal 135A, and is also connected to the wiring 131 of the circuit unit 130.

The probe 140 is pushed into the inner walls of the through holes 113 and 123 by the pressure-sensitive adhesive layer 110A from the upper surface (the surface in the + Z axis direction) around the through holes 123 of the base material layer 120 along the inner walls of the through holes 113 and 123. It is provided in a state of being. As described above, the probe 140 is provided in a state of being embedded in the pressure-sensitive adhesive layer 110A so as to be exposed from the lower surface 112 of the pressure-sensitive adhesive layer 110, and is provided on the surface of the skin 200 of the pressure-sensitive adhesive layer 110. It is arranged so as to be in contact with the surface of the skin 200 on the sticking side (-Z axis direction). The probe 140 has an exposed region on the side where the pressure-sensitive adhesive layer 110 is attached to the skin 200 (in the −Z axis direction) where a part of the probe 140 is exposed. When the pressure-sensitive adhesive layer 110 is attached to the skin 200, the probe 140 comes into contact with the skin 200 and detects a biological signal. The biological signal is, for example, an electric signal representing an electrocardiographic waveform, an electroencephalogram, a pulse, or the like.

The probe 140 is attached to the upper surface (+ Z-axis direction) of the frame 132 of the circuit unit 130 located around the through hole 123 of the base material layer 120 on the side of attachment to the biological surface (-Z-axis direction). It has a connecting surface 141 connected to the frame 132 of the above. The connection surface 141 may be connected to both the wiring 131 and the frame 132.

The probe 140 has a rectangular shape in a plan view, is larger than the through holes 113 and 123 of the pressure-sensitive adhesive layer 110 and the base material layer 120, and has holes 140A arranged in a matrix. At the ends (parts of the four ends) of the probe 140 in the X and Y directions, the ladder-shaped sides of the probe 140 may protrude.

The probe 140 can have holes 140A over its main surface, preferably having holes 140A in the connecting surface 141. The probe 140 can form a hole 140A in the connecting surface 141 by having the hole 140A over the entire surface of the main surface thereof or around the end thereof. By providing the hole 140A in the connection surface 141, the pressure-sensitive adhesive layer 110A can be exposed from the hole 140A formed in the connection surface 141, so that the pressure-sensitive adhesive layer 110A can be displayed on the upper surface (+ Z-axis direction) of the frame 132 of the circuit unit 130. Can be easily brought into contact with the surface).

The probe 140 is formed by using electrodes. The electrodes will be described with reference to FIGS. 3 and 4. In addition, in FIGS. 3 and 4, the electrode corresponds to the probe 140 shown in FIGS. 1 and 2, and the hole of the electrode corresponds to the hole 140A shown in FIGS. 1 and 2.

(electrode)
FIG. 3 is a perspective view of the electrodes. As shown in FIG. 3, the electrode 10 has a plurality of holes 13 penetrating the plate-shaped (sheet-shaped) member having a pair of main surfaces 11 and 12 parallel to each other in the thickness direction (Z-axis direction) of the electrode 10. Is formed in a grid pattern.

The main surfaces 11 and 12 are flat surfaces, respectively. The main surface 11 is the main surface of one of the electrodes 10 (in the + Z axis direction), and is the surface of the electrodes 10. The main surface 12 is a main surface located in the direction opposite to the main surface 11 (−Z axis direction), and is the back surface of the electrode 10. The main surfaces 11 and 12 are formed in a rectangular shape in a plan view. In the present embodiment, the rectangle includes not only a rectangle and a square but also a shape in which the corners of the rectangle and the square are chamfered.

The size of the electrode 10 in a plan view is preferably 5 mm to 50 mm.

The thickness of the electrode 10 is preferably 0.1 μm to 100 μm. When the thickness of the electrode 10 is 0.1 μm to 100 μm, the electrode 10 has strength and is easy to handle.

The plurality of holes 13 are arranged on the main surface 11 in a square grid pattern, and are arranged on the main surface 11 in parallel in two intersecting axial directions (X-axis direction and Y-axis direction) at substantially equal intervals. All the holes 13 are formed substantially uniformly in size and shape. The plurality of holes 13 do not have to be evenly spaced.

As shown in FIG. 4, the hole 13 is formed in a circular shape in a plan view. The diameter L of the hole 13 can be appropriately designed according to the size of the main surface 11, and is preferably 100 nm to 10 mm, more preferably 300 nm to 5 mm, and even more preferably 600 μm to 2 mm. The shape of the hole 13 may be elliptical. When the shape of the hole 13 is elliptical, the diameter L of the hole 13 preferably has the above-mentioned numerical value on the major axis.

The distance P between the holes 13 depends on the shape and size of the holes 13, but is preferably 100 nm to 10 mm, more preferably 300 nm to 5 mm, and even more preferably 600 nm to 2 mm or less. The distance P between the holes 13 means the shortest distance between the adjacent holes 13. Since the holes 13 are formed in a circular shape in a plan view, the distance between the holes 13 refers to the distance between the closest points of the adjacent holes 13.

The opening ratio of the holes 13 is 2% to 80%, preferably 10% to 70%, and more preferably 30% to 60%. When the opening ratio of the holes 13 is less than 2%, the area of the adhesive layer exposed from the holes 13 of the electrode 10 is small when the adhesive layer is installed on the electrode 10. Therefore, when the electrode 10 is peeled from the adhesive surface together with the adhesive layer, the peeling adhesive force of the adhesive layer with respect to the adhesive surface becomes too small. If the aperture ratio of the holes 13 exceeds 80%, the area of the adhesive layer exposed from the holes 13 of the electrode 10 is too large. Therefore, when the electrode 10 is peeled off from the adhesive surface together with the adhesive layer, the adhesive force becomes too strong.

The aperture ratio is the ratio of the sum of the areas of the holes 13 to the total area of the main surface (main surface 11 or main surface 12) of the electrode 10 including the area of the holes 13, and is expressed by the following formula (1). expressed.
Aperture ratio (%) = sum of the areas of the holes 13 (cm ² ) / the total area of the main surface (main surface 11 or 12) of the electrode 10 including the area of the holes 13 (cm ² ) × 100 ...・ (1)

The number of holes 13 is preferably 2000 / cm ² or less, more preferably 1000 / cm ² or less, more preferably 500 / cm ² or less. If the number of holes 13 is 2000 pieces / cm ² or less, when the adhesive layer is installed on the electrode 10, the number of adhesive layers exposed from the holes 13 of the electrode 10 can be sufficiently secured, and the conductivity can be easily maintained. .. The lower limit of the number of holes 13 may be two or more.

The electrode 10 can be formed by using a conductive composition containing a conductive polymer and a binder resin.

As the conductive polymer, for example, polythiophene, polyacetylene, polypyrrole, polyaniline, polyphenylene vinylene and the like can be used. These may be used alone or in combination of two or more. Among these, it is preferable to use a polythiophene compound. PEDOT / PSS doped with polystyrene sulfonic acid (poly4-styrene sulfonate; PSS) to poly 3,4-ethylenedioxythiophene (PEDOT) because it has lower contact impedance with the living body and has high conductivity. Is more preferable to use.

The content of the conductive polymer is preferably 0.20 parts by mass to 20 parts by mass, and more preferably 2.5 parts by mass to 15 parts by mass with respect to 100 parts by mass of the conductive composition. , 3.0 parts by mass to 12 parts by mass, more preferably. When the content is in the range of 0.20 parts by mass to 20 parts by mass with respect to the conductive composition, excellent conductivity, toughness and flexibility can be imparted to the conductive composition.

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

As the binder resin, a water-soluble polymer, a water-insoluble polymer, or the like can be used. As the binder resin, it is preferable to use a water-soluble polymer from the viewpoint of compatibility with other components contained in the conductive composition. The water-soluble polymer contains a polymer (hydrophilic polymer) that is completely insoluble in water and has hydrophilicity.

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

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

The content of the binder resin is preferably 5 parts by mass to 140 parts by mass, more preferably 10 parts by mass to 100 parts by mass, and 20 parts by mass to 70 parts by mass with respect to 100 parts by mass of the conductive composition. It is more preferably parts by mass. When the content is in the range of 5 parts by mass to 140 parts by mass with respect to the conductive composition, excellent conductivity, toughness and flexibility can be imparted to the conductive composition.

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

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

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

The flexibility is a property that can suppress the occurrence of damage such as breakage in the bent portion after bending the electrode 10 which is a cured product of the conductive composition.

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

Examples of the cross-linking agent include zirconium compounds such as zirconium salts; titanium compounds such as titanium salts; borides such as boric acid; isocyanate compounds such as blocked isocyanate; aldehyde compounds such as dialdehyde such as glyoxal; alkoxyl group-containing compounds and methylol groups. Examples include contained compounds. These may be used alone or in combination of two or more. Of these, a zirconium compound, an isocyanate compound, or an aldehyde compound is preferable from the viewpoint of reactivity and safety.

The content of the cross-linking agent is preferably 0.2 parts by mass to 80 parts by mass, more preferably 1 part by mass to 40 parts by mass, and 3.0 parts by mass with respect to 100 parts by mass of the conductive composition. More preferably, it is by mass to 20 parts by mass. When the content is within the range of 0.2 parts by mass to 80 parts by mass with respect to 100 parts by mass of the conductive composition, excellent toughness and flexibility can be imparted to the conductive composition.

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

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

The content of the plasticizer is preferably 0.2 parts by mass to 150 parts by mass, more preferably 1.0 part by mass to 90 parts by mass, and 10 parts by mass to 10 parts by mass with respect to 100 parts by mass of the conductive composition. It is more preferably 70 parts by mass. When the content is in the range of 0.2 parts by mass to 150 parts by mass with respect to 100 parts by mass of the conductive composition, excellent toughness and flexibility can be imparted to the conductive composition.

At least one of the cross-linking agent and the plasticizer may be contained in the conductive composition. By including at least one of the cross-linking agent and the plasticizer in the conductive composition, the electrode 10 can improve toughness and flexibility.

When the conductive composition contains a cross-linking agent but no plasticizer, the electrode 10 can further improve toughness, that is, both tensile strength and tensile elongation, and also improve flexibility. Can be done.

When the conductive composition contains a plasticizer but does not contain a cross-linking agent, the tensile elongation of the electrode 10 can be improved, so that the toughness of the electrode 10 as a whole can be improved. Moreover, the flexibility of the electrode 10 can be improved.

It is preferable that both the cross-linking agent and the plasticizer are contained in the conductive composition. By including both the cross-linking agent and the plasticizer in the conductive composition, the electrode 10 is imparted with even better toughness.

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

The conductive composition is prepared by mixing the above-mentioned components in the above-mentioned ratios.

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

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

An example of a method for manufacturing the electrode 10 will be described. After applying the conductive composition to the surface of the release base material, the conductive composition is heated to allow the cross-linking agent contained in the conductive composition to promote the cross-linking reaction of the binder resin and cure the binder resin. As a result, a cured product of the conductive composition is obtained. Then, the surface of the cured product is pressed into a predetermined shape using a press machine or the like to form the cured product. As a result, as shown in FIG. 3, an electrode 10 is obtained in which holes 13 having substantially uniform sizes and shapes are arranged in a square lattice on the main surface 11.

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

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

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

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

The heating temperature of the aqueous solution of the conductive composition is set to a temperature at which the reaction of the cross-linking agent contained in the aqueous solution of the conductive composition can proceed. The heating temperature is preferably 100 ° C. to 200 ° C., more preferably 110 ° C. to 150 ° C. When the heating temperature is in the range of 100 ° C. to 200 ° C., the reaction of the cross-linking agent is likely to proceed, and the curing of the binder resin can be promoted.

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

As described above, the electrode 10 is a sheet-shaped electrode having main surfaces 11 and 12, has a plurality of holes 13, and has an aperture ratio of the holes 13 on the main surfaces 11 and 12 of 8% to 80%. .. As a result, when the pressure-sensitive adhesive layer 110 is installed as an adhesive layer on the main surface 11 side, the electrode 10 is a biological surface that the pressure-sensitive adhesive layer 110 comes into contact with as an adhered portion through the holes 13 of the electrode 10. It is possible to suppress a decrease in the adhesive force required for connection with the skin 200. Therefore, when the pressure-sensitive adhesive layer 110 is installed on the main surface 11 side, the electrode 10 can suppress the peeling between the pressure-sensitive adhesive layer 110 and the skin 200. The electrode 10 can have, for example, a peeling adhesive force of 0.010 N / 10 mm or more.

The peeling adhesive strength is obtained by, for example, a method based on JIS Z 0237: 2009, or a method obtained by changing the test plate specified in JIS Z 0237: 2009 to another adherend. As the peeling adhesive strength, for example, the peeling strength when the electrode 10 is adhered to a test plate or an adherend and a peeling test is performed at a tensile speed of 300 mm / min and a peeling angle of 180 ° can be used. The peeling adhesive strength is preferably 0.010N / 10mm to 0.8N / 10mm, and more preferably 0.080N / 10mm to 0.55N / 10mm. If the peeling adhesive strength is less than 0.010 N / 10 mm, when the pressure-sensitive adhesive layer 110 is attached to the electrode 10 and used, the adhesive strength of the pressure-sensitive adhesive layer 110 to the skin 200 is low, and the adhesion may not be sufficient. There is. If the peeling adhesive strength exceeds 0.8 N / 10 mm, the pressure-sensitive adhesive layer 110 has a high adhesive strength, which may hinder the reattachment of the pressure-sensitive adhesive layer 110.

Further, the electrode 10 can secure a sufficient area where the main surface 11 or the main surface 12 is in contact with the skin 200 by setting the aperture ratio of the holes 13 on the main surfaces 11 and 12 to 2% to 80%. Therefore, the electrode 10 can stably maintain the conductivity with the skin 200.

Therefore, when the pressure-sensitive adhesive layer 110 is installed on the main surface 11 side, the electrode 10 can have conductivity while suppressing peeling between the pressure-sensitive adhesive layer 110 and the skin 200. Therefore, when the electrode 10 is used as a biosensor, the measurement can be performed while suppressing the electrode 10 from peeling from the skin for a long period of time.

The electrode 10 can have 2000 holes / cm ² or less. As a result, when the adhesive layer is installed on the electrode 10, the number of adhesive layers exposed from the holes 13 of the electrode 10 can be sufficiently secured, and the contact area of the electrode 10 with respect to the skin 200 can be maintained. Therefore, when the pressure-sensitive adhesive layer 110 is installed on the main surface 11 side of the electrode 10, it is possible to further suppress the peeling between the pressure-sensitive adhesive layer 110 and the skin 200, and to secure the conductivity. be able to.

The electrode 10 can be configured by arranging the holes 13 on the main surfaces 11 and 12 in a square grid pattern. As a result, when the adhesive layer is installed on the electrode 10, the adhesive layer can be brought into contact with the skin 200 substantially evenly over the entire circumference of the electrode 10 through the holes 13 of the electrode 10 and with the skin 200 of the electrode 10. The contact area can be secured almost evenly. Therefore, when the adhesive layer is installed on the main surface 11 side of the electrode 10, the adhesive layer can stably maintain the adhesive force to the skin 200 even if the skin 200 expands and contracts in all directions, and the skin 200 can be maintained. The conductivity with and can be stably maintained.

The electrode 10 can penetrate the hole 13 perpendicularly to the main surfaces 11 and 12. As a result, when the pressure-sensitive adhesive layer 110 is installed on the electrode 10, the pressure-sensitive adhesive layer 110 can be easily passed through the hole 13. Therefore, since the electrode 10 can easily bring the pressure-sensitive adhesive layer 110 into contact with the skin 200 through the holes 13, the connection between the pressure-sensitive adhesive layer 110 and the skin 200 can be stably maintained. Further, since the influence of the viscosity of the pressure-sensitive adhesive layer 110 can be reduced, the optimum adhesive layer can be used according to the type of skin 200.

As shown in FIGS. 1 and 2, the probe 140 is fixed to the frame 132 by a fixing tape 145 overlaid on the four end portions in a state where the four end portions are arranged on the frame 132. To. The fixing tape 145 is adhered to the frame 132 through a gap such as a hole 140A of the probe 140.

The fixing tape 145 is, for example, a copper tape and has a rectangular annular shape in a plan view. An adhesive is applied to the lower surface of the fixing tape 145. The fixing tape 145 is provided on the frame 132 so as to surround the four sides of the probe 140 outside the openings of the through holes 113 and 123 in a plan view, and fixes the probe 140 to the frame 132. The fixing tape 145 may be a metal tape other than copper.

In this way, the pressure-sensitive adhesive layer 110A and the base material layer 120A are laminated on the fixing tape 145 and the probe 140 in a state where the four end portions of the probe 140 are fixed to the frame 132 with the fixing tape 145. When the pressure-sensitive adhesive layer 110A and the base material layer 120A are pressed downward, the probe 140 is pushed along the inner walls of the through holes 113 and 123, and the pressure-sensitive adhesive layer 110A is pushed into the hole 140A of the probe 140. ..

The probe 140 is pushed down to a position where the central portion is substantially flush with the lower surface 112 of the pressure-sensitive adhesive layer 110 in a state where the four end portions are fixed on the frame 132 by the fixing tape 145. Therefore, when the probe 140 is applied to the skin 200 of a living body (see FIG. 2), the pressure-sensitive adhesive layer 110A is adhered to the skin 200, and the probe 140 can be brought into close contact with the skin 200.

The thickness of the probe 140 is preferably thinner than the thickness of the pressure-sensitive adhesive layer 110. The thickness of the probe 140 is preferably 0.1 μm to 100 μm, more preferably 1 μm to 50 μm, similar to the thickness of the electrode 10 described above.

Further, the peripheral portion (rectangular annular portion) surrounding the central portion in the plan view of the pressure-sensitive adhesive layer 110A is located on the fixing tape 145. In FIG. 2, the upper surface of the pressure-sensitive adhesive layer 110A is substantially flat, but the central portion may be recessed below the peripheral portion. The base material layer 120A is superposed on a substantially flat upper surface of the pressure sensitive adhesive layer 110A.

The pressure-sensitive adhesive layer 110A and the base material layer 120A may be made of the same material as the pressure-sensitive adhesive layer 110 and the base material layer 120, respectively. Further, the pressure-sensitive adhesive layer 110A may be made of a material different from that of the pressure-sensitive adhesive layer 110. Further, the base material layer 120A may be made of a material different from that of the base material layer 120.

Although the thickness of each part is exaggerated in FIG. 2, the thicknesses of the pressure-sensitive adhesive layers 110 and 110A are actually 10 μm to 300 μm, and the thicknesses of the base material layers 120 and 120A are 1 μm to 1. It is 300 μm. The thickness of the wiring 131 is 0.1 μm to 100 μm, the thickness of the substrate 133 is about several hundred μm, and the thickness of the fixing tape 145 is 10 μm to 300 μm.

Further, as shown in FIG. 2, when the probe 140 and the frame 132 are in direct contact with each other to ensure an electrical connection, the fixing tape 145 is a tape made of resin or the like having no conductivity. May be good.

Further, in FIG. 2, the fixing tape 145 covers the side surfaces of the frame 132 and the substrate 133 in addition to the probe 140, and reaches the upper surface of the base material layer 120. However, since the fixing tape 145 only needs to be able to bond the probe 140 and the frame 132, it does not have to reach the upper surface of the base material layer 120, and does not have to cover the side surface of the substrate 133, and the side surface of the frame 132 may be covered. It does not have to be covered.

Further, the substrate 133 and the two substrates 135 may be one integrated substrate. In this case, wiring 131, two frames 132, and terminal 135A are provided on the surface of one substrate, and the electronic device 150 and the battery 160 are mounted.

The electronic device 150 is installed on the upper surface 122 of the base material layer 120 and is electrically connected to the wiring 131. The electronic device 150 has a rectangular shape in a cross-sectional view. Terminals are provided on the lower surface (-Z direction) of the electronic device 150. Examples of the material for the terminals of the electronic device 150 include solder, conductive paste, and the like.

As shown in FIG. 1, the electronic device 150 includes an ASIC (application specific integrated circuit) 150A, an MPU (Micro Processing Unit) 150B, a memory 150C, and a wireless communication unit 150D as an example, and includes a circuit unit. It is connected to the probe 140 and the battery 160 via 130. The electronic device 150 processes the biological signal acquired via the probe 140.

The ASIC 150A includes an A / D (Analog to digital) converter. The electronic device 150 is driven by the electric power supplied from the battery 160 and acquires the biological signal measured by the probe 140. The electronic device 150 performs processing such as filtering and digital conversion on the biological signal, and the MPU 150B obtains the added average value of the biological signal acquired a plurality of times and stores the biological signal in the memory 150C. As an example, the electronic device 150 can continuously acquire biological signals for 24 hours or more. Since the electronic device 150 may measure a biological signal for a long time, it is devised to reduce power consumption.

The wireless communication unit 150D is a transceiver used when the test apparatus for the evaluation test reads out the biological signal stored in the memory 150C in the evaluation test by wireless communication, and communicates at 2.4 GHz as an example. The evaluation test is, for example, a test of the JIS 60601-2-47 standard. The evaluation test is a test for confirming the operation performed after the completion of the biological sensor that detects the biological signal as a medical device. The evaluation test requires that the attenuation rate of the biological signal extracted from the biological sensor is less than 5% with respect to the biological signal input to the biological sensor. This evaluation test is performed on all finished products.

As shown in FIG. 2, the battery 160 is provided on the upper surface 122 of the base material layer 120. As the battery 160, a lead storage battery, a lithium ion secondary battery, or the like can be used. The battery 160 may be a button battery type. The battery 160 is an example of a battery. The battery 160 has terminals provided on its lower surface. The terminals of the battery 160 are connected to the probe 140 and the electronic device 150 via the circuit unit 130. The capacity of the battery 160 is set so that the electronic device 150 can measure the biological signal for 24 hours or more, for example.

The cover 170 covers the base material layer 120, the circuit unit 130, the substrate 135, the probe 140, the fixing tape 145, the electronic device 150, and the battery 160. The cover 170 has a base 170A and a protrusion 170B protruding from the center of the base 170A in the + Z direction. The base portion 170A is a portion located around the cover 170 in a plan view, and is a portion lower than the protruding portion 170B. A recess 170C is provided on the lower side of the protrusion 170B. In the cover 170, the lower surface of the base 170A is adhered to the upper surface 122 of the base material layer 120. The substrate 135, the electronic device 150, and the battery 160 are housed in the recess 170C. The cover 170 is adhered to the upper surface 122 of the base material layer 120 with the electronic device 150, the battery 160, and the like housed in the recess 170C.

The cover 170 not only serves as a cover for protecting the circuit unit 130, the electronic device 150, and the battery 160 on the base material layer 120, but also provides internal components from the impact applied to the stickable biosensor 100 from the upper surface side. It has a role as a shock absorbing layer to protect. As the cover 170, for example, silicone rubber, soft resin, urethane, or the like can be used.

FIG. 5 is a diagram showing a circuit configuration of the stick-on biosensor 100. Each probe 140 is connected to the electronic device 150 and the battery 160 via the wiring 131 and the wiring 135B of the substrate 135. The two probes 140 are connected in parallel to the electronic device 150 and the battery 160.

As described above, the stick-on biosensor 100 includes the probe 140, and the probe 140 is provided with a connection surface 141 connected to the frame 132 of the circuit unit 130 on the stick-on side (-Z-axis direction) of the skin 200. ing. By connecting the probe 140 to the frame 132 via the connecting surface 141, it is possible to make it difficult for the probe 140 to be separated from the frame 132. As a result, the stick-on biosensor 100 can stabilize the connection between the probe 140 and the frame 132, so that the continuity between the probe 140 and the frame 132 can be stably ensured. Further, in the sticking type biosensor 100, the probe 140 is arranged so as to be in contact with the surface of the skin 200 on the sticking side (−Z axis direction) of the pressure sensitive adhesive layer 110 to the surface of the skin 200. Can have a stable continuity. Therefore, the stick-on biosensor 100 can have conductivity while suppressing peeling between the pressure-sensitive adhesive layer 110 installed on one surface of the probe 140 and the skin 200 on which the probe 140 is installed. Therefore, even if the stick-on biosensor 100 is used for a long time by sticking the stick-on biosensor 100 on the skin, the stick-on biosensor 100 can stably measure the biometric information.

The stick-on biosensor 100 has one or more holes 140A in the connection surface 141 of the probe 140, and the circuit portion 130 is opposite to the side (-Z-axis direction) of the probe 140 and the skin 200 on the surface. It can be connected on the side (+ Z axis direction). The probe 140 has a hole 140A in the connection surface 141, so that the pressure-sensitive adhesive layer 110A exposed from the hole 140A formed in the connection surface 141 is formed with the upper surface (plane in the + Z axis direction) of the frame 132 of the circuit unit 130. Can be contacted. As a result, the state in which the probe 140 is connected to the frame 132 by the pressure-sensitive adhesive layer 110A can be maintained. Therefore, in the stick-on biosensor 100, the probe 140 and the frame 132 can be more stably connected by the pressure-sensitive adhesive layer 110A exposed through the hole 140A formed in the connection surface 141.

The stick-on biosensor 100 includes a probe 140 formed by using the above electrode 10 (see FIG. 3), and the probe 140 can have an aperture ratio of 8% to 80%. As a result, the stick-on biosensor 100 can suppress a decrease in the adhesive force of the pressure-sensitive adhesive layer 110 with respect to the skin 200 through the hole 140A of the probe 140, so that the probe 140 is peeled off from the skin 200. Can be suppressed. Further, since the stick-on biosensor 100 can secure the conductivity in the probe 140, it can stably have the conductivity with the skin 200. Therefore, the stick-on biosensor 100 has conductivity while more stably suppressing peeling between the pressure-sensitive adhesive layer 110 installed on one surface of the probe 140 and the skin 200 on which the probe 140 is installed. it can. Therefore, even if the stick-on biosensor 100 is used for a long time by sticking the stick-on biosensor 100 on the skin, the stick-on biosensor 100 can stably measure the biometric information.

The stick-on biosensor 100 can reduce the number of holes 140A of the probe 140 to 300 / cm ² or less. As a result, it is possible to further suppress the occurrence of peeling between the pressure-sensitive adhesive layer 110 and the skin 200 that have passed through the hole 140A of the probe 140, and it is possible to secure conductivity. Therefore, the stickable biosensor 100 can be stably used in a state of being stuck to the skin 200 for a long time.

The stick-on biosensor 100 can be configured by arranging the holes 140A of the probe 140 in a square grid pattern on the main surface. As a result, the pressure-sensitive adhesive layer 110 can be brought into contact with the skin 200 substantially evenly from the hole 140A over the entire circumference of the probe 140, and the contact area of the probe 140 with the skin 200 can be secured substantially evenly. Therefore, in the stick-on biosensor 100, even if the surface of the skin 200 moves and the skin 200 in contact with the probe 140 expands and contracts in all directions, the pressure-sensitive adhesive layer 110 is attached to the skin 200 through the hole 140A of the probe 140. The sticking state can be maintained stably.

The stick-on biosensor 100 can penetrate the hole 140A of the probe 140 perpendicularly to the main surface of the probe 140. As a result, the stick-on biosensor 100 can easily bring the pressure-sensitive adhesive layer 110 into contact with the skin 200 through the hole 140A of the probe 140, so that the connection between the pressure-sensitive adhesive layer 110 and the skin 200 can be easily formed. ..

After being used for measuring biometric information, the stickable biosensor 100 can be reused by collecting it if necessary, taking out the electronic device 150 and the battery 160, and exchanging them.

The stick-on biosensor 100 is a measuring device that measures biological information by sensing an electric signal from a living body, and is a stick-on electrocardiograph, a stick-on electrosurgical meter, a stick-on sphygmomanometer, a stick-on pulse rate monitor, and a stick-type muscle. It can be used as an electric meter, a stick-on thermometer, a stick-on accelerometer, and the like.

Above all, the stick-on biosensor 100 is preferably used as a stick-on electrocardiograph. In the electrocardiogram examination, the attached biosensor 100 acquires the minute action potential (electromotive force) of the myocardium generated by the heartbeat of the subject as biometric information, so that the electrocardiogram of arrhythmia, ischemic heart disease, etc. Anomalies are investigated. In the electrocardiogram examination, the stick-on biosensor 100 is attached to the chest, both wrists, both ankles, etc. of the subject, and the action potential of the myocardium generated by the heartbeat of the subject by the probe 140 is used as an electric signal. It can be detected stably. The stick-on biosensor 100 can acquire the electrocardiogram waveform more accurately by using the electric signal detected by the probe 140.

(Other forms of biosensors)
As shown in FIG. 6, the stick-on biosensor 100 may be provided with a moisture barrier layer 115 in the through holes 113 and 123 instead of the pressure-sensitive adhesive layer 110A.

The water barrier layer 115 has a function of suppressing the water existing around the probe 140 from penetrating the stick-on biosensor 100 in the thickness direction. The moisture barrier layer 115, together with the pressure-sensitive adhesive layer 110, forms the lower surface of the stickable biosensor 100. By providing the moisture barrier layer 115 around the lower surface of the probe 140, it is possible to prevent the moisture around the probe 140 from permeating in the thickness direction of the stick-on biosensor 100, so that the probe 140 comes into contact with the skin 200 of the living body. Moisture can be maintained at the interface between the lower surface of the probe 140 and the skin 200. Further, since the moisture is maintained at the interface between the lower surface of the probe 140 and the skin 200, the drying of the probe 140 can be suppressed, so that the increase and variation of the impedance of the probe 140 due to the drying of the surface of the probe 140 can be suppressed. can do.

The moisture permeability of the moisture barrier layer 115 is lower than that of the pressure-sensitive adhesive layer 110 and the base material layer 120. Specifically, the moisture permeability of the moisture barrier layer 115 is, for example, less than 1000 g / m ² · day, preferably 600 g / m ² · day or less, more preferably 300 g / m ² · day or less, still more preferably. , 80 g / m ² · day or less, and for example 0.001 g / m ² · day or more.

Examples of the material of the moisture barrier layer 115 include rubber resins (polyisobutylene resin, butyl rubber resin, SBR resin, natural rubber / SBR resin, etc.), polystyrene resins, and polyolefin resins (polypoly resin, polyethylene). (Based resin layer), acrylic resin, polyvinyl alcohol type resin and the like. These resins may be used alone or in combination of two or more.

The moisture barrier layer 115 may have air bubbles. As the moisture barrier layer 115, a foam such as a polypropylene resin or an acrylic resin can be used.

The moisture barrier layer 115 preferably has pressure-sensitive adhesiveness. Examples of the moisture barrier layer having such pressure-sensitive adhesiveness include a rubber-based resin layer (rubber-based pressure-sensitive adhesive layer) and more preferably a polyisobutylene-based resin layer (polyisobutylene-based pressure-sensitive adhesive layer). ..

The polyisobutylene-based resin layer is formed from a polyisobutylene-based composition. The polyisobutylene-based composition contains polyisobutylene as a rubber component. The content of polyisobutylene in the polyisobutylene-based composition is, for example, preferably 10% by mass to 50% by mass, more preferably 20% by mass to 40% by mass.

The polyisobutylene-based composition preferably contains a highly water-absorbent resin and a pressure-sensitive adhesive. Thereby, the rubber-based composition such as the polyisobutylene-based composition can have excellent water barrier property and pressure-sensitive adhesive property.

Examples of the superabsorbent polymer include maleic anhydride-based resin (for example, crosslinked product of sodium salt of maleic anhydride / maleic anhydride copolymer), polyacrylate-based resin, polysulfone-based resin, and polyacrylamide-based resin. Examples thereof include resins and polyvinyl alcohol-based resins, and preferably maleic anhydride-based resins and the like. The content of the highly water-absorbent resin is, for example, preferably 1 part by mass to 10 parts by mass, and more preferably 3 parts by mass to 5 parts by mass with respect to 100 parts by mass of polyisobutylene.

Examples of the tackifier include rosin resin, terpene resin (for example, terpene-aromatic liquid resin, etc.), kumaron inden resin, phenol resin, phenol formalin resin, xylene formalin resin, and petroleum resin. Examples thereof include resins (for example, C5 series petroleum resin, C9 series petroleum resin, C5 / C9 series petroleum resin, etc.), and preferably petroleum resin. The content of the tackifier is preferably, for example, 10 parts by mass to 200 parts by mass, and more preferably 50 parts by mass to 150 parts by mass with respect to 100 parts by mass of polyisobutylene.

The polyisobutylene-based composition can further contain a softening agent, a filler, a cross-linking agent and the like, if necessary.

Examples of the softening agent include liquid rubbers such as polybutene, liquid isoprene rubber, and liquid butadiene rubber; oils such as paraffin oil and naphthenic oil; and esters such as phthalate ester and phosphoric acid ester, which are preferable. , Liquid rubber can be mentioned. The content of the softening agent is preferably 10 parts by mass to 200 parts by mass, more preferably 50 parts by mass to 150 parts by mass with respect to 100 parts by mass of polyisobutylene.

Fillers include, for example, heavy calcium carbonate, light calcium carbonate, and calcium carbonate such as white luster; carbon black, talc, mica, clay, mica powder, bentonite, silica, alumina, aluminum silicate, titanium oxide, glass powder, etc. Boron nitride powder; metal powder such as aluminum powder and iron powder; resin powder such as acrylic resin powder and styrene resin powder; metal hydroxides such as aluminum hydroxide and magnesium hydroxide, preferably calcium carbonate. Be done. The content of the filler is preferably 10 parts by mass to 200 parts by mass, and more preferably 50 parts by mass to 150 parts by mass with respect to 100 parts by mass of polyisobutylene.

Examples of the cross-linking agent include isocyanate compounds such as hexamethylene diisocyanate. The content of the cross-linking agent is, for example, preferably 1 part by mass to 10 parts by mass, and more preferably 3 parts by mass to 5 parts by mass with respect to 100 parts by mass of polyisobutylene.

The polyisobutylene-based composition can appropriately contain a known additive such as a foaming agent and a plasticizer in an arbitrary ratio.

The rubber-based resin layer is preferably a styrene-butadiene rubber (SBR) -based resin layer and a natural rubber / SBR-based resin layer, and more preferably an SBR-based resin, from the viewpoint of fixing stability to the skin. Layers are mentioned.

The SBR-based resin layer is formed from an SBR-based composition. The SBR-based composition contains SBR as a rubber component. The content of SBR in the SBR-based composition is preferably 10% by mass to 50% by mass, more preferably 20% by mass to 40% by mass.

Similar to the polyisobutylene-based composition, the SBR-based composition may also contain a highly water-absorbent resin, a tackifier, a softener, a filler, a cross-linking agent, and the like.

The natural rubber / SBR resin layer is formed from a natural rubber / SBR composition. The natural rubber / SBR-based composition contains natural rubber and SBR as a rubber component. The total content of the natural rubber and SBR in the natural rubber / SBR-based composition is preferably 10% by mass to 50% by mass, more preferably 20% by mass to 40% by mass.

The natural rubber / SBR-based composition may also contain a highly water-absorbent resin, a tackifier, a softener, a filler, a cross-linking agent, and the like, similarly to the polyisobutylene-based composition.

The thickness of the moisture barrier layer 115 is substantially the same as the thickness of the pressure-sensitive adhesive layer 110. Specifically, the thickness of the moisture barrier layer 115 is preferably 10 μm to 300 μm, more preferably 20 μm to 100 μm, and even more preferably 30 μm to 50 μm.

(Modification example)
In this embodiment, the electrode 10 does not have to have a hole 13 in its main surface 11.

In the present embodiment, the number of holes 13 can be appropriately optimized according to the size and the like of the electrodes 10, and may be one or more.

In the present embodiment, as shown in FIG. 7, the electrode 10 may have a plurality of recesses 14 recessed from the main surface 11 to the main surface 12 in addition to the holes 13. As a result, the contact area of the main surface 12 of the electrode 10 with the skin 200 can be increased, so that the electrode 10 can secure conductivity more stably with the skin 200.

In the present embodiment, the arrangement of the holes 13 is not limited to the square grid shape, but may be an oblique grid shape or a hexagonal grid shape (staggered shape). Further, the plurality of holes 13 may be arranged regularly or irregularly.

In the present embodiment, the shape of the hole 13 may be a polygon such as a rectangle in a plan view. For example, as shown in FIG. 8, the hole 13 may be formed in a rectangular shape in a plan view. The rectangle may be a square or a rectangle. In this case, the length L of each side of the hole 13 is preferably 100 nm to 10 mm, more preferably 300 nm to 5 mm, and even more preferably 600 μm to 2 mm. When the shape of the hole 13 is rectangular, it is preferable that the long side has the above-mentioned numerical value.

In the present embodiment, the shapes and dimensions of the holes 13 may not be the same.

In the present embodiment, the through holes 113 and 123 of the stick-on biosensor 100 are formed in a rectangular shape in a plan view, but may have other shapes such as a circle.

In this embodiment, the stick-on biosensor 100 does not have to include an electronic device 150, a battery 160, or a cover 170.

In the present embodiment, the stick-on biosensor 100 may be provided with a release sheet made of a resin such as polyethylene terephthalate on the lower surfaces of the pressure-sensitive adhesive layer 110, the pressure-sensitive adhesive layer 110A, and the probe 140.

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

<Example 1>
[Example 1-1]
(Preparation of conductive composition)
Aqueous solution containing PEDOT / PSS as a conductive polymer (PEDOT / PSS concentration: 1%, "Clevious PH1000", manufactured by Heleus) 38.0 parts by mass, and an aqueous solution containing modified polyvinyl alcohol as a binder resin (modified polyvinyl alcohol concentration) : 10%, "Gosenex Z-410", manufactured by Nippon Synthetic Chemical Co., Ltd.) and an aqueous solution containing a zirconium-based compound as a cross-linking agent (zirconium-based compound concentration: 10%, "Safelink SPM-01", 2.0 parts by mass of Nippon Synthetic Chemical Co., Ltd., 2.0 parts by mass of glycerin (manufactured by Wako Pure Chemical Industries, Ltd.) as a plasticizer, and silicone-based surfactant ("Silface SAG002", Nissin Chemical Co., Ltd.) as a surfactant. 0.08 parts by mass (manufactured by Kogyo Co., Ltd.) was added to the ultrasonic bath. Then, the aqueous solution containing these components was mixed in an ultrasonic bath for 30 minutes to prepare a uniform aqueous solution of the conductive composition.

Since the concentration of PEDOT / PSS in the aqueous solution containing PEDOT / PSS is about 1%, the content of PEDOT / PSS in the aqueous solution of the conductive composition is 0.38 parts by mass. Since the concentration of the modified polyvinyl alcohol in the aqueous solution containing the modified polyvinyl alcohol is about 10%, the content of the modified polyvinyl alcohol in the aqueous solution of the conductive composition is 1.00 parts by mass. Since the concentration of the zirconium compound in the aqueous solution containing the zirconium compound is about 10%, the content of the zirconium compound in the aqueous solution of the conductive composition is 0.20 parts by mass. The balance is the solvent in the aqueous solution of the conductive composition.

The contents of the conductive polymer, binder resin, cross-linking agent, plasticizer and surfactant with respect to 100 parts by mass of the conductive composition are 10.4 parts by mass, 27.3 parts by mass and 5.5 parts by mass, respectively. , 54.6 parts by mass and 2.2 parts by mass.

(Preparation of electrodes)
After applying the prepared aqueous solution of the conductive composition on a PET film (3 cm × 3 cm), the aqueous solution of the conductive composition is heated and dried at 120 ° C. for 10 minutes to dry the cured product of the conductive composition (length 1 cm × width 1 cm). , Thickness 10 μm) was prepared. Then, the cured product was pressed with a press machine in a state of being in close contact with the release sheet (PET film). As a result, a probe sheet having electrodes (pore diameter: 300 μm, aperture ratio: 30%) in which a plurality of circular holes formed on the main surface are arranged in a square lattice pattern was produced on the release sheet.

(Evaluation of difficulty in peeling)
When evaluating the difficulty of peeling off the electrode, a moisture barrier layer and an adherend to be attached to the electrode were prepared.

(1) Preparation of Moisture Barrier Layer SBR resin (product "SLY-25", manufactured by Nitto Denko Co., Ltd.) is diluted with a toluene solvent so that the ratio of the SBR resin and the toluene solvent is 10: 1 and mixed. The solution was prepared. The mixed solution was applied to the surface of the second release sheet (PET film) and dried by heating. As a result, a moisture barrier layer sheet having pressure-sensitive adhesiveness was obtained. The shape of the moisture barrier layer was substantially rectangular in plan view (1 cm × 1 cm, thickness 25 μm).

(2) Preparation of adherends The pig skin (Yucatan micropig (YMP) skin set, manufactured by Charles River Laboratories, Japan) that has been frozen and stored at -80 ° C is naturally thawed to remove subcutaneous fat. Pretreatment was performed. Then, the pretreated pig skin was cut into 30 mm × 50 mm × 5 mm. The cut pig skin was used as an adherend.

(3) Measurement of Peeling Adhesive Strength A water barrier layer adjusted as described above was formed on one main surface of the prepared electrode to prepare a test piece. Then, the main surface on which the electrodes of the test piece were exposed was attached to the adherend adjusted as described above, and crimped by reciprocating a 2 kg roller once. Then, the test piece was kept in a standard environment of 23 ° C. and 50% RH for 5 minutes. Then, under the same standard environment, using a desktop precision universal testing machine (“Autograph AGS-50NX”, manufactured by Shimadzu Corporation), the test piece was subjected to the conditions of a peeling angle of 180 ° and a tensile speed of 100 mm / min. A 180 ° peeling test was performed, and the 180 ° peeling adhesive strength (unit: N / 10 mm) of the test piece to the adherend was measured. The measurement was performed three times (N = 3), and the average of those measured values was taken as the peeling adhesive strength (initial peeling strength). The measurement results are shown in FIG. Further, when the peeling adhesive strength at room temperature obtained by the above test was 0.010 mN / 10 mm or more, it was evaluated as good (denoted as A in Table 1). When the peeling adhesive strength was less than 0.010 N / 10 mm or exceeded 0.8 N / 10 mm, it was evaluated as defective (denoted as B in Table 1). Table 1 shows the measurement results and evaluation results of the peeling adhesive strength.

[Example 1-2]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the distance between the electrode holes was changed to 600 μm and the aperture ratio was changed to 14.9%.

[Example 1-3]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the distance between the electrode holes was changed to 900 μm and the aperture ratio was changed to 8.1%.

[Example 1-4]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the hole diameter of the electrode was changed to 600 μm and the aperture ratio was changed to 46.8%.

[Example 1-5]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the hole diameter of the electrode was changed to 900 μm and the aperture ratio was changed to 55.9%.

[Example 1-6]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the hole diameter of the electrode was changed to 1200 μm and the aperture ratio was changed to 53.9%.

[Example 1-7]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the distance between the electrode holes was changed to 1200 μm and the aperture ratio was changed to 6.1%.

[Comparative Example 1-1]
In Example 1-1, the same procedure as in Example 1-1 was carried out except that the distance between the electrode holes was changed to 2000 μm and the aperture ratio was changed to 1.2%.

Table 1 shows the shape, diameter, spacing between holes, aperture ratio, and peeling adhesive force of the electrodes of each example and comparative example.

As shown in FIGS. 9 and 1, in Examples 1-1 to 1-7, the aperture ratio was 6.1% or more, and the peeling adhesive strength was 0.012 N / 10 mm or more. On the other hand, in Comparative Example 1-1, the aperture ratio was 1.2% and the peeling adhesive strength was 0.000 N / 10 mm.

Therefore, it was confirmed that when the aperture ratio of the electrode is 6% to 56%, the peeling adhesive force can be 0.012N / 10mm or more, and high adhesiveness can be obtained. Therefore, in the biosensor according to the embodiment, since the electrode has an aperture ratio in a predetermined range, when it is used as an electrode of the biosensor, it can have stable adhesive force and conductivity. Therefore, it can be said that the biosensor can be effectively used to bring the biosensor into close contact with the skin of the subject and continuously measure the electrocardiogram for a long time (for example, 24 hours).

<Example 2>
[Example 2-1]
(Preparation of electrodes)
The electrodes prepared in Example 1-1 were used. The number of holes per unit area of the electrode was 261 / cm ² .

(Evaluation of difficulty in peeling)
The peeling adhesive strength was measured and evaluated in the same manner as in Example 1-1. The measurement results are shown in FIG. Further, as in Example 1-1, the peeling adhesive strength at room temperature obtained by the above test was evaluated. Table 2 shows the measurement results and the evaluation results of the peeling adhesive strength.

(Evaluation of expansion / contraction rate at break)
The expansion / contraction rate at break when the specimen was subjected to a 180 ° peeling test was measured. The measurement result of the expansion / contraction rate at the time of breaking is shown in FIG. Table 2 shows the measurement results and the measurement results of the expansion / contraction rate at the time of fracture.

[Example 2-2]
In Example 2-1 and the same as in Example 2-1 except that the hole diameter of the electrode and the distance between the holes were changed to 600 μm, and the number of holes per unit area of the electrode was changed to 61 pieces / cm ^2. It was done in the same way.

[Example 2-3]
Same as Example 2-1 except that the hole diameter of the electrodes and the distance between the holes were changed to 900 μm and the number of holes per unit area of the electrodes was changed to 26 / cm ^2. I went there.

[Example 2-4]
Same as Example 2-1 except that the hole diameter of the electrode and the distance between the holes were changed to 1200 μm and the number of holes per unit area of the electrode was changed to 14 / cm ^2. I went there.

[Comparative Example 2-1]
Same as Example 2-1 except that the hole diameter of the electrode and the distance between the holes were changed to 100 μm and the number of holes per unit area of the electrode was changed to 2500 / cm ^2. I went there.

Table 2 shows the shape of the electrode holes, the hole diameter, the distance between the holes, the number of holes per unit area, the peeling adhesive force, and the expansion / contraction rate at break in each of the Examples and Comparative Examples.

As shown in FIGS. 10 and 2, in Examples 2-1 to 2-4, the number of holes per unit area was 14 or more, and the peeling adhesive strength was 0.082 N / 10 mm or more. On the other hand, as shown in Table 2, in Comparative Example 2-1 the number of holes per unit area was 2500 holes / cm ² , and the peeling adhesive strength was 0.000 N / 10 mm.

Further, as shown in FIGS. 11 and 2, in Examples 2-1 to 2-4, even if the peeling adhesive force was 0.082 N / 10 mm or more, the expansion / contraction rate at break was 5% or more.

Therefore, it was confirmed that when the number of holes per unit area of the electrode is 261 or less, the electrode can have a peeling adhesive force of 0.082 N / 10 mm or more and can have high adhesiveness. It was also confirmed that the electrode can have an expansion / contraction rate of 5% or more at the time of breaking.

Therefore, the electrode has a number of holes per unit area of a predetermined value or less, and the expansion / contraction rate at break is also a predetermined value or more. Therefore, when the electrode is used as a probe of a biosensor, one surface of the probe is used. It is possible to have conductivity while suppressing peeling between the adhesive layer installed on the surface and the surface of the living body on which the probe is installed. Therefore, since the biosensor can have stable adhesive strength and conductivity, it is effective for keeping the biosensor in close contact with the skin of the subject and continuously measuring the electrocardiogram for a long time (for example, 24 hours). It can be said that it can be used.

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

10 Electrodes 11, 12 Main surface 13, 140A Hole 100 Stick-on biosensor (biological sensor)
110 Pressure-sensitive adhesive layer 120 Base material layer 130 Circuit part 140 Probe 141 Connection surface 150 Electronic device 160 Battery 170 Cover

Claims (7)

A pressure-sensitive adhesive layer for sticking to the surface of the living body,
An electrode arranged so as to be in contact with the biological surface on the side where the pressure-sensitive adhesive layer is attached to the biological surface,
An electronic device that processes biological signals acquired via the electrodes,
A circuit unit for connecting the electrode and the electronic device is provided .
The electrodes, biosensors which have a one or more holes penetrating in the thickness direction of the electrode in the patch side have a connecting surface to be connected to the circuit portion, and at said connecting surface to the living body surface. The electrodes are formed in a plate shape having a pair of main surfaces parallel to each other .
Before SL circuit portion, and the electrode, the biological sensor according to claim 1, which is connected on the opposite side to the sticking-side to the living body surface. The electrode is a plate-shaped electrode containing a conductive polymer and a binder resin and having a pair of main surfaces parallel to each other.
The electrode has a plurality of holes penetrating in the thickness direction thereof.
The biosensor according to claim 1 or 2, wherein the opening ratio of the hole on the main surface is 2% to 80%. The biosensor according to claim 2 or 3, wherein the number of holes is 2000 holes / cm ² or less. The biosensor according to any one of claims 2 to 4, wherein a plurality of the holes are arranged in a square grid, an orthorhombic grid, or a hexagonal grid on the main surface. The biosensor according to any one of claims 2 to 5, wherein the hole penetrates perpendicularly to the main surface. The biosensor according to any one of claims 2 to 6, wherein at least one of the pair of main surfaces includes a recess.

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