JP2018102404A - Bioelectrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bioelectrode capable of acquiring a bioelectric signal with a high degree of precision even in a situation in which an artifact can be easily taken into a bioelectric signal such as situations in which a body motion is large, and sweats are produced.SOLUTION: A bioelectrode 10 consists of a laminate in which at least an uneven layer 5 having an uneven shape and an electrode layer 1 are laminated. The height h of a convex part of the uneven layer 5 is 0.1 mm or more, and the thickness t of the electrode layer 1 is 8 mm or less. The difference between the height h of the convex part of the uneven layer 5 and the thickness t of the electrode layer 1 (h-t) is 0.01-8 mm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a bioelectrode and a fabric including the same.

  2. Description of the Related Art Conventionally, bioelectrodes used for acquiring and recording bioelectric signals such as electrocardiograms, electromyograms, electroencephalograms, heart rate variability, and applying electrical stimulation to the living body are known. The bioelectrode is used in close contact with the body surface.

  Bioelectric signals have been acquired in a state where the living body is at rest, but in recent years, attempts have been made to acquire bioelectric signals continuously for a long time in daily life, and to make use for health management and the like. For example, it is a so-called wearable electrode in which the bioelectrode is fixed to clothing, etc., and bioelectric signals acquired with the bioelectrode are transmitted in real time to electronic devices such as smartphones and tablet terminals, and various sports, health, medical, entertainment, etc. Attempts have been made to use it in the field.

Japanese Patent Laid-Open No. 2006-106877

  However, in a situation where body movement is large, such as during exercise, artifacts (noise) are easily captured in the bioelectric signal when the bioelectric signal is acquired by the bioelectrode, and the bioelectric signal can be acquired with high accuracy. There is a problem that it becomes difficult.

  Further, in a situation where the person sweats, the bioelectrode in contact with the skin can easily slide and move, and artifacts are easily taken into the bioelectric signal when the bioelectric signal is acquired by the bioelectrode.

  In view of the above-described problems of the prior art, the present invention is capable of acquiring a bioelectric signal with high accuracy even in a situation where artifacts are likely to be captured in the bioelectric signal, such as a situation where body movement is large or sweating. The main purpose is to provide an electrode.

  As a result of intensive studies in view of the above problems, the present inventors have found that a biological electrode comprising at least a concavo-convex layer having a concavo-convex shape and an electrode layer has a large body movement or sweat. The present inventors have found that bioelectric signals can be obtained with high accuracy even in situations where artifacts are likely to be captured in bioelectric signals, such as the situation. The present invention has been completed by further studies based on these findings.

That is, this invention provides the invention of the aspect hung up below.
Item 1. A biological electrode comprising a laminate in which at least an uneven layer having an uneven shape and an electrode layer are stacked.
Item 2. Item 2. The biological electrode according to Item 1, wherein the height h of the convex portion of the concave-convex layer is 0.1 mm or more.
Item 3. Item 3. The biological electrode according to Item 1 or 2, wherein the electrode layer has a thickness t of 8 mm or less.
Item 4. Item 4. The biological electrode according to any one of Items 1 to 3, wherein a difference (ht) between a height h of the convex portion of the uneven layer and a thickness t of the electrode layer is 0.01 to 8 mm.
Item 5. The biological electrode according to any one of Items 1 to 4, wherein the uneven layer has a distance w between adjacent convex portions of 1 to 8 mm.
Item 6. Claim | item 1-5 whose angle (theta) of the said front-end | tip part is 30 degrees-140 degrees, when the cross section of the front-end | tip part of the convex part of the said uneven | corrugated layer is acquired in the lamination direction of the said laminated body. Bioelectrode.
Item 7. Item 7. The biological electrode according to any one of Items 1 to 6, wherein the microhardness of the convex portion of the concave-convex layer is 0.01 to 30 N / mm ² .
Item 8. Item 8. The biological electrode according to any one of Items 1 to 7, wherein when the uneven layer is observed from a direction perpendicular to the stacking direction of the stacked body, the shape of the convex portion is a triangle, a quadrangle, or a semicircle.
Item 9. Item 9. The biological electrode according to any one of Items 1 to 8, wherein the electrode layer is composed of a fiber knitted fabric or a conductive resin film.
Item 10. It has a moisture permeation suppression layer having an uneven shape,
Item 10. The biological electrode according to any one of Items 1 to 9, wherein the moisture permeation suppression layer constitutes the uneven layer.
Item 11. A biological electrode comprising an electrode layer having an uneven shape.
Item 12. Item 12. The biological electrode according to any one of Items 1 to 11, wherein the electrode layer is provided on a base material layer.
Item 13. Item 13. A fabric in which the bioelectrode according to any one of Items 1 to 12 is fixed.

  According to the present invention, various bioelectric signals such as an electrocardiogram, an electromyogram, an electroencephalogram, and a heart rate variability can be obtained even in a situation where artifacts are likely to be incorporated into the bioelectric signal such as a situation where body movement is large or sweating. A biological electrode that can be obtained with high accuracy can be provided. The bioelectrode of the present invention can be used not only to acquire and record bioelectric signals but also to effectively apply electrical stimulation to the living body. Moreover, this invention can also provide the fabric provided with the said bioelectrode. The fabric can be used as a wearable electrode by processing it into clothing or the like.

It is a schematic sectional drawing of an example of the bioelectrode of this invention. It is a schematic sectional drawing of an example of the bioelectrode of this invention. It is a schematic sectional drawing of an example of the bioelectrode of this invention. It is the schematic diagram which planarly viewed the uneven | corrugated layer from the electrode layer side. It is the schematic diagram which looked at the uneven | corrugated shape of an uneven | corrugated layer from the side. It is an electrocardiogram waveform at the time of stillness and walking of Example 1. It is an electrocardiogram waveform at the time of stationary and walking of Comparative Example 1.

  The bioelectrode of the present invention is characterized by comprising a laminate in which at least an uneven layer having an uneven shape and an electrode layer are stacked. Hereinafter, the bioelectrode of the present invention and the fabric including the same will be described in detail.

  The biological electrode 10 of the present invention includes an electrode layer 1 on the surface as shown in FIGS. 1 to 3, for example.

  The material constituting the electrode layer is not particularly limited as long as it has conductivity, and examples thereof include a conductive fiber knitted fabric, a conductive resin film, and a metal foil. From the viewpoint of obtaining bioelectric signals with higher accuracy even in situations where artifacts are likely to be captured in bioelectric signals, such as large situations or sweating conditions, conductive fiber knitted fabric, conductive resin are preferable. A film is mentioned, Furthermore, from a viewpoint which is also excellent in the wearing feeling of a bioelectrode, More preferably, a conductive fiber knitted fabric is mentioned.

  From the viewpoint of imparting conductivity to the fiber knitted fabric, the fiber knitted fabric preferably contains conductive fibers. It does not specifically limit as a conductive fiber, A well-known fiber provided with electroconductivity can be used. Specific examples of the conductive fiber include metal plating fiber, conductive polymer fiber, metal fiber, carbon fiber, slit fiber, conductive material-containing fiber, and the like. A conductive fiber may be used individually by 1 type, and may be used in combination of 2 or more types.

  The metal-plated fiber is not particularly limited, and a known one can be used. For example, the surface of the synthetic fiber is covered with a metal such as silver, copper, gold, or stainless steel, or an alloy containing at least one of them. Fibers that have been removed. The synthetic fiber to which metal plating is applied is preferably nylon fiber or polyester fiber.

  The conductive polymer fiber is not particularly limited, and known ones can be used. For example, poly3,4-ethylenedioxythiophene (PEDOT) and polystyrenesulfonic acid (poly-4-styrenesulfonate; PSS) are used. Examples thereof include PEDOT / PSS fibers using doped PEDOT / PSS, and fibers obtained by combining PEDOT / PSS and a matrix resin. Examples of the matrix resin include polyvinyl alcohol (PVA). Alternatively, a synthetic fiber impregnated with a conductive polymer may be used. Examples of the synthetic fiber include polyester fiber and nylon fiber.

  The metal fiber is not particularly limited, and examples thereof include fibers composed of metals such as silver, nickel, copper, iron, and tin, or alloys containing at least one of these metals.

  As the conductive material-containing fiber, a fiber composed of a fiber-forming polymer such as a polyester-based polymer or a polyamide-based polymer in which a conductive substance is uniformly dispersed (that is, a conductive polymer) is useful. Examples of conductive materials include conductive carbon blacks such as furnace black, ketjen black, acetylene black, and channel black; simple metals such as silver, nickel, copper, iron, and tin; copper sulfide, zinc sulfide, and copper iodide And metal compounds.

  Among the conductive fibers, silver-plated nylon fibers, silver-plated polyester fibers, and fibers that are combined with PEDOT / PSS and a matrix resin such as PVA are preferable.

  Although it does not restrict | limit especially as an electrical resistance value of an electroconductive fiber, For example, about 0.1-100,000 (ohm) / 10cm is mentioned.

  The fiber knitted fabric constituting the electrode layer may be composed only of conductive fibers, or may further include other fibers. The other fiber is preferably a heat-bonded fiber or a heat-bonded fiber (hereinafter referred to as a heat-bonded fiber or the like). The difference between the heat-bonded fiber and the heat-bonded fiber may be distinguished by the strength of the bonding force generated by cooling from the semi-molten or softened state. Those with weak strength are heat-bonded fibers. Although this distinction is not clear and includes an ambiguous paste, the point is that any fiber that can bond the intersections of the fibers by heat treatment may be used. For example, examples of polyurethane fibers as heat-sealing fibers include Mobilon R and Mobilon RL manufactured by Nisshinbo Textile Co., Ltd. As examples of polyurethane fibers used as heat-sealing fibers and heat-sealing fibers, Asahi Kasei Examples include Roika SF manufactured by Co., Ltd. When the fiber knitted fabric further includes heat-bonding fibers and the like, the surface smoothness of the electrode layer is improved by performing a heat press treatment on the electrode layer including the conductive fibers and the heat-bonding fibers (that is, the surface The roughness (Ra) can be reduced) and the adhesion to the skin (body surface) can be improved. By improving the adhesion of the bioelectrode to the skin, bioelectric signals can be obtained with higher accuracy.

  The heat-sealable fiber is not particularly limited as long as the fibers are bonded to each other by, for example, hot pressing at about 80 ° C. or higher, and preferably, a polyurethane fiber, a nylon fiber, a polyester fiber, and the like are used. One type of heat-sealing fiber or the like may be used alone, or two or more types may be used in combination.

  In the case where the fiber knitted fabric further includes a heat-bonded fiber or the like, from the viewpoint of obtaining a bioelectric signal with higher accuracy, the mass ratio of the conductive fiber and the heat-bonded fiber or the like in the fiber knitted fabric (conductive (Fiber: heat fusion fiber etc.) is preferably about 50:50 to 98: 2, more preferably about 60:40 to 90:10.

  It does not restrict | limit especially as the fineness of the electroconductive fiber which comprises the fiber knitted fabric, For example, about 1-300 dtex is mentioned. The conductive fiber may be a monofilament or a multifilament. The fineness of the heat-fusible fiber or the like is not particularly limited, and examples thereof include about 1 to 300 dtex. The heat fusion fiber or the like may be a monofilament or a multifilament. The knitting method of the fiber knitted fabric is not particularly limited. For example, in addition to weft knitting such as single knitting (also referred to as flat knitting or tengu knitting), milling knitting (also referred to as rubber knitting), pearl knitting, and smooth knitting. Well-known knitting methods including warp knitting and braiding can be mentioned.

  The conductive resin film used as the electrode layer is not particularly limited, and examples thereof include those formed by printing conductive ink. Preferable specific examples of the conductive resin film include a printed film on which conductive ink (including paste-like one) such as silver ink, copper ink, and carbon ink is printed, and a conductive filler dispersed film such as metal powder. It is done.

  Moreover, it does not restrict | limit especially as metal foil used as an electrode layer, However, As metal foil, copper foil, aluminum foil, nickel foil, etc. are mentioned.

  Furthermore, from the viewpoint of obtaining bioelectric signals with higher accuracy, it is preferable that the surface of the fiber knitted fabric has either a hydrophobic surface or a hydrophilic surface.

  For example, when the hydrophobicity of the electrode layer surface is very high, moisture released from the skin can be efficiently retained between the skin and the electrode layer surface. Thereby, the contact impedance between skin and an electrode layer reduces, As a result, it becomes difficult to take in an artifact in a bioelectric signal, and the acquisition precision of a bioelectric signal improves.

  Moreover, when the hydrophilicity of the electrode layer surface is very high, the moisture released from the skin can be efficiently retained in the electrode layer. As a result, the moisture content of the electrode itself is improved, and as a result, artifacts are less likely to be taken into the bioelectric signal, and the bioelectric signal acquisition accuracy is improved.

  For example, the method for providing the hydrophobic treatment layer on the electrode layer 1 is not particularly limited, and examples thereof include a method of immersing the electrode layer 1 in a hydrophobic surface treatment solution. Moreover, you may perform drying and heat processing after immersion, and can make the durability of a hydrophobic treatment layer more excellent by doing so.

  It does not restrict | limit especially as a hydrophobic surface treatment liquid, A well-known hydrophobic surface treatment liquid can be used. Examples of the hydrophobic surface treatment liquid include a fluorine-based hydrophobic surface treatment liquid, a silicone-based surface treatment liquid, and a wax-based surface treatment liquid. Commercially available products of these hydrophobic surface treatment solutions are readily available.

  A method for providing a hydrophilic treatment layer on the surface of the electrode layer 1 is not particularly limited, and examples thereof include a method of immersing the electrode layer 1 in a hydrophilic surface treatment solution. Moreover, you may perform drying and heat processing after immersion, and can make the durability of a hydrophilic treatment layer more excellent by doing so.

  It does not restrict | limit especially as a hydrophilic surface treatment liquid, A well-known hydrophilic surface treatment liquid can be used. Examples of the hydrophilic surface treatment liquid include a polyurethane-based hydrophilic surface treatment liquid, a polyether-based surface treatment liquid, and a polyester-based surface treatment liquid. Commercially available products of these hydrophilic surface treatment solutions are readily available.

  The thickness t of the electrode layer 1 is not particularly limited, but is preferably 8 mm or less, more preferably about 0.01 to 5 mm, and still more preferably 0.02 from the viewpoint of obtaining a biological body electrical signal with higher accuracy. About 2 mm is mentioned. More specifically, when the electrode layer 1 is composed of a fiber knitted fabric, the thickness t of the electrode layer 1 is preferably about 0.05 to 5 mm, more preferably about 0.1 to 2 mm mm. . Moreover, when the electrode layer 1 is comprised with the electroconductive resin film, as thickness t of the electrode layer 1, Preferably it is about 0.01-5 mm, More preferably, about 0.02-2 mm is mentioned. Moreover, when the electrode layer 1 is comprised with metal foil, As thickness t of the electrode layer 1, Preferably it is about 0.005-5 mm, More preferably, about 0.02-2 mm is mentioned.

  In the bioelectrode of the present invention, an uneven layer 5 is laminated together with the electrode layer 1 as shown in the schematic diagrams of FIGS. As for the uneven | corrugated layer 5, the surface by the side of the said electrode layer 1 has an uneven | corrugated shape.

  In the bioelectrode of the present invention, the electrode layer 1 of the bioelectrode 10 is worn so as to be pressed against the skin, so that a large local pressure due to the plurality of convex portions 51 of the uneven layer 5 is passed through the electrode layer 1. Thus, the adhesion between the electrode layer 1 and the skin is effectively enhanced. As a result, the contact impedance between the skin and the electrode layer 1 is reduced, and as a result, even when the body movement is large, artifacts are hardly captured in the bioelectric signal, and the bioelectric signal is obtained with high accuracy. It becomes possible. In addition, as described above, in a sweaty situation, since the bioelectrode in contact with the skin is easy to slide and move, artifacts are easily captured in the bioelectric signal, but the movement of the bioelectrode in contact with the skin does not occur. If suppressed, moisture due to sweat increases the adhesion between the electrode layer 1 and the skin, making it difficult for artifacts to be taken into the bioelectric signal. According to the bioelectrode of the present invention, since the adhesion with the skin is enhanced, the slip of the bioelectrode due to sweat is effectively suppressed. For this reason, the bioelectrode of the present invention is particularly effective for obtaining bioelectric signals in sweating situations.

  In addition, in the conventional bioelectrode, even when an electrical stimulus is applied, the sensitivity of the bioelectrode is deteriorated and it may be difficult to apply the electrical stimulus. However, the bioelectrode of the present invention includes a skin and an electrode layer. Since the contact impedance between them is reduced, the sensitivity is high, and electrical stimulation can be effectively applied to the living body.

  FIG. 4 is a schematic view of the concavo-convex layer 5 as viewed from the electrode layer 1 side. The y direction in FIG. 4 is the stacking direction of the stacked body constituting the biological electrode 10. As shown in FIG. 4, the concavo-convex layer 5 is provided with a plurality of convex portions 51, and concave portions 52 are formed between the convex portions 51. The shape of each convex portion 51 when the concavo-convex layer 5 is viewed from the electrode layer side is not particularly limited, and examples thereof include polygons such as a triangle, a quadrangle, a pentagon, and a hexagon, a circle, and an indefinite shape. FIG. 4A shows an example of a quadrangle, and FIG. 4B shows an example of a circle.

  In addition, from the viewpoint of increasing the local pressure by the plurality of convex portions 51 of the uneven layer 5 and improving the adhesion between the electrode layer 1 and the skin more effectively, the uneven layer 5 is viewed from a direction perpendicular to the stacking direction. When observed, the shape of the convex portion 51 is preferably a triangle, a quadrangle (including a trapezoid), or a semicircular shape. Examples of a preferable shape of the convex portion 51 include a quadrangular pyramid and a cone.

  FIG. 5 is a schematic view of the uneven shape of the uneven layer 5 viewed from the side (viewed from the z direction). In the bioelectrode of the present invention, the height h of the convex portion 51 of the concavo-convex layer 5 is preferably 0.2 mm or more, more preferably 0.5 to 0.5 from the viewpoint of obtaining a biological body electrical signal with higher accuracy. About 8 mm, More preferably, about 1-3 mm is mentioned. In addition, the height h of the convex part 51 means the height difference of the convex part 51 and the recessed part 52, as shown in FIG. Although illustration is omitted, in the present invention, the concavo-convex layer 5 includes only a plurality of convex portions 51, and the concave portion 52 exposes a layer located under the concavo-convex layer 5 (that is, the convex portion 51). The height h and the thickness d of the concavo-convex layer 5 may be the same.

  Further, from the viewpoint of increasing the local pressure by the plurality of convex portions 51 of the concave / convex layer 5 and improving the adhesion between the electrode layer 1 and the skin more effectively, the height h of the convex portion 51 of the concave / convex layer 5 is increased. And the difference (ht) between the thickness t of the electrode layer 1 is preferably about 0.01 to 8 mm, more preferably 0.01 to 5 mm, and about 0.02 to 3 mm. More preferably, it is especially preferable that it is about 1-3 mm. When the difference is within such a range, the biological body electrical signal can be acquired with higher accuracy.

  From the viewpoint of increasing the local pressure by the plurality of convex portions 51 of the concave-convex layer 5 and more effectively increasing the adhesion between the electrode layer 1 and the skin, the distance w between adjacent convex portions is, for example, 1 to 1 About 10 mm, Preferably it is about 1-8 mm, More preferably, it is about 2-6 mm, More preferably, about 2-5 mm is mentioned. In addition, the distance w between adjacent convex parts means the distance with the closest convex part about each convex part. In addition, when the convex portions 51 are provided irregularly, one arbitrary convex portion 51 is selected, and the above-mentioned distances are selected for the top 30 convex portions 51 that are closest to the convex portion 51. Let w be the measured average value. As for the height h of the above-described convex portion 51, if the height of the convex portion 51 is not uniform, the average value of the 30 is used.

  The shape of the tip portion of the convex portion 51 of the concavo-convex layer 5 is not particularly limited, but the local pressure by the plurality of convex portions 51 of the concavo-convex layer 5 is increased to further improve the adhesion between the electrode layer 1 and the skin. From the standpoint of enhancing, for example, when the cross section of the tip portion of the convex portion 51 of the concavo-convex layer 5 is obtained in the stacking direction of the laminate constituting the bioelectrode, the angle (θ) of the tip portion is 30 °. It is preferably ˜150 °, more preferably 40 ° to 140 °, and even more preferably 60 ° to 130 °. When the angle (θ) is in such a range, the biological body electrical signal can be acquired with higher accuracy.

  From the viewpoint of improving the air permeability of the bioelectrode, the uneven layer 5 preferably has a through hole in the stacking direction of the bioelectrode (not shown). The position of the through hole is not particularly limited, but is preferably provided in the recess 52. Further, the number of through holes is not particularly limited, but a plurality of through holes are preferably provided from the viewpoint of improving air permeability. For example, each through hole 52 can be provided with a through hole.

From the viewpoint of increasing the local pressure by the plurality of convex portions 51 of the concavo-convex layer 5 and more effectively improving the adhesion between the electrode layer 1 and the skin, the microhardness of the convex portion 51, preferably 0.01~200N / mm ^2, more preferably 0.05~200N / mm ^2, and more preferably about include about 0.1~20N / mm ^2. In the present invention, the microhardness of the convex portion 51 of the concave / convex layer 5 is a value measured by the following method.

(Measurement of micro hardness)
Measurement is performed using a microhardness meter in accordance with the provisions of ISO 14577-1. The load speed (test speed) is 0.15 mN / sec, the holding time is 2 seconds, the indentation depth is 10 μm, and the indenter is a triangular pan indenter (angle between ridges 115 degrees).

  Further, from the viewpoint of increasing the wearing pressure of the bioelectrode while increasing the local pressure by the plurality of convex portions 51 of the concavo-convex layer 5 and more effectively improving the adhesion between the electrode layer 1 and the skin, the concavo-convex layer The Asker C hardness of the five convex portions 51 is preferably about 5 to 80 degrees, more preferably about 10 to 75 degrees, and still more preferably about 10 to 70 degrees. In the present invention, the Asker C hardness of the convex portion 51 of the concave-convex layer 5 is a value measured by the following method.

(Measurement of Asker C hardness)
In accordance with the regulations of SRIS 0101, measurement is performed using an Asker rubber hardness tester C type. In addition, when the thickness of the sample to be measured is less than 1 cm, the measurement is performed by stacking the samples to be 1 cm or more.

  Although it does not restrict | limit especially as a material which comprises the uneven | corrugated layer 5, While raising the local pressure by the several convex part 51 of the uneven | corrugated layer 5, raising the adhesiveness of the electrode layer 1 and skin more effectively, From the viewpoint of enhancing the wearing feeling of the bioelectrode, a resin is preferably used. Preferred resins include silicone resins, urethane resins, acrylic resins, olefin resins, polyester resins, polyamide resins, and epoxy resins.

  As will be described later, the biological electrode of the present invention has the moisture permeation suppression layer 3, and the water permeation suppression layer 3 constitutes the concavo-convex layer 5 by forming the water permeation suppression layer 3 into a concavo-convex shape. (See FIG. 2).

  The thickness d of the concavo-convex layer 5 is not particularly limited, but the height h of the convex portion 51 of the concavo-convex layer 5 is preferably 0.2 mm or more, more preferably about 0.5 to 8 mm, and still more preferably 1 to 1. About 4 mm is mentioned.

  In the bioelectrode of the present invention, for example, as shown in FIGS. 1 to 3, the electrode layer 1 is preferably provided on the base material layer 2. Thereby, the shape stability and mechanical strength of the bioelectrode of the present invention can be increased.

  Although it does not restrict | limit especially as a raw material which comprises the base material layer 2, From the viewpoint of improving the adhesiveness to the skin of a bioelectrode, the raw material excellent in the flexibility is preferable. As a material which comprises the base material layer 2, Preferably, rubbers, such as chloroprene rubber, etc., and resin, such as polyester, a polyurethane, and polyethylene, are mentioned. The material constituting the base material layer 2 may be one type or two or more types. From the viewpoint of improving the adhesion of the bioelectrode to the skin, when the base material layer 2 is made of a resin, the resin is preferably sponge-like.

  The base material layer 2 may be a single layer or a multilayer. Moreover, when the base material layer 2 is a multilayer, the raw material which comprises each layer may be the same, and may differ.

  Although it does not restrict | limit especially as thickness of the base material layer 2, From a viewpoint of improving the adhesiveness to the skin of a bioelectrode, improving the shape stability and mechanical strength of a bioelectrode, Preferably it is 0.1-10 mm. About 1 degree, More preferably, about 1-8 mm is mentioned.

  In the bioelectrode of the present invention, for example, as shown in FIGS. 1 to 3, it is preferable to further include a moisture permeation suppression layer 3 between the electrode layer 1 and the base material layer 2. In the biological electrode of the present invention, the provision of the moisture permeation suppression layer 3 makes it possible to more efficiently retain moisture released from the skin between the skin and the electrode layer surface. The electric signal can be acquired with higher accuracy.

  The water permeation suppression layer 3 is not particularly limited as long as it can suppress the water permeation of the bioelectrode, and can be composed of a resin film, a nonwoven fabric, or the like. Examples of the material constituting the moisture permeation suppression layer 3 include polyurethane, polyethylene terephthalate, acrylic resin, polyethylene, polypropylene, and nylon. Moreover, a moisture permeation suppression layer can be comprised with a nonwoven fabric. The moisture permeation suppression layer 3 may be a single layer or a multilayer. Moreover, when the moisture permeation suppression layer 3 is a multilayer, the materials constituting each layer may be the same or different.

The moisture permeability of the moisture permeation suppression layer 3 is not particularly limited, but is preferably 200 g / m ² / h or less, more preferably 150 g / m ² / h or less. In addition, the moisture permeability of the moisture permeation suppression layer 3 is a value measured by the method of JIS L1099 (A-1 method).

  In addition, as shown in FIG. 2, the moisture permeation suppression layer 3 can also form the concavo-convex layer 5 by making the moisture permeation suppression layer 3 into a concavo-convex shape. About the uneven | corrugated shape in this case, it is the same as that of the above-mentioned uneven | corrugated layer 5. FIG.

  The thickness when the moisture permeation suppression layer 3 does not constitute the uneven layer 5 is not particularly limited, and may be about 1 to 500 μm, more preferably about 10 to 200 μm, for example.

  The method for laminating the electrode layer, the concavo-convex layer, the base material layer, and the moisture permeation suppression layer is not particularly limited, and examples thereof include hot pressing and a method of providing an adhesive layer. For example, when bonding an electrode layer and an uneven | corrugated layer by hot press, it is preferable to heat-press on the conditions of the temperature of about 80-200 degreeC, the pressure of about 0.05-20 MPa, and about 1 to 60 seconds. Moreover, when bonding an uneven | corrugated layer and a moisture permeation | transmission suppression layer by hot press, it is preferable to heat-press on the conditions of the temperature of about 80-200 degreeC, the pressure of about 0.01-10 MPa, and about 5-120 seconds. Moreover, when bonding a base material layer and a moisture permeation | transmission suppression layer by hot press, it is preferable to heat-press on the conditions of about 80-200 degreeC of temperature, about 0.01-10 MPa of pressure, and about 5 to 120 second second.

  Examples of the method for providing the adhesive layer include a method in which a urethane nonwoven fabric, a nylon nonwoven fabric, or the like is disposed between the layers and thermocompression bonded, or a method using an adhesive. The adhesive is not particularly limited, and a known adhesive can be used. For example, an adhesive such as a polyurethane-based adhesive or a modified silicone polymer can be used. When providing an adhesive layer, the thickness of the adhesive layer is not particularly limited, and for example, about 1 to 300 μm, and more preferably about 10 to 200 μm.

  The bioelectrode of the present invention may be further provided with a layer other than these layers as necessary. The total thickness of the biological electrode of the present invention is not particularly limited, and for example, about 0.1 to 12 mm, and more preferably about 1 to 10 mm.

  By connecting the bioelectrode of the present invention and a device for recording a bioelectric signal by wiring or the like, it is possible to acquire and record bioelectric signals such as an electrocardiogram, an electromyogram, an electroencephalogram, and a heartbeat fluctuation. Moreover, it can also be used in order to give an electrical stimulus with respect to a biological body by using the biological electrode of this invention as electrodes, such as a low frequency therapeutic device.

  The bioelectrode of the present invention can be used by being fixed to a cloth, for example. Specifically, for example, a bioelectric signal can be obtained by combining the bioelectrode and the fabric of the present invention into clothing, and bringing the electrode layer surface into close contact with the skin. For example, by recording and analyzing a bioelectric signal acquired from a bioelectrode in real time while wearing such clothing, it can be used in various fields such as sports, health, medical care, and entertainment.

  The method for fixing the bioelectrode of the present invention to the fabric is not particularly limited, and for example, a urethane non-woven fabric, a nylon non-woven fabric or the like may be disposed between them and thermocompression-bonded, or an adhesive may be used. It may be sewn to the fabric.

  As the material of the fabric, those used in ordinary clothing can be used, and for example, natural fiber materials such as cotton and wool, synthetic fiber materials such as polyester and nylon can be used without particular limitation.

  The fabric may be processed into a form such as clothing, and the form can be appropriately designed according to the type of bioelectric signal to be acquired. For example, in the case of acquiring an electrocardiogram, a form such as underwear in which a bioelectrode is arranged on the chest close to the heart of the living body is preferable.

  In the bioelectrode of the present invention, the electrode layer 1 may have a concavo-convex shape as shown in FIG. When the electrode layer 1 has the same uneven shape as the uneven layer 5 described above, the uneven layer 5 may not be provided. By making the electrode layer 1 concavo-convex, the local pressure by the plurality of convex portions 51 of the concavo-convex layer 5 can be increased, and the adhesion between the electrode layer 1 and the skin can be more effectively increased. Therefore, even in such a mode, the bioelectrode of the present invention can acquire a bioelectric signal with high accuracy even in a situation where artifacts are likely to be captured in the bioelectric signal, such as a situation where body movement is large or sweating. can do. Even when the bioelectrode of the present invention has such a configuration, the above-described moisture permeation suppressing layer, adhesive layer, base material layer, and the like can be provided.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples.

<Preparation of electrode layer>
Example 1
The electrode layer is nylon / silver plated fiber (nylon multifilament manufactured by Mitsufuji Fiber Industries Co., Ltd. [trade name: AGposs]) 70 dtex / 34f and polyurethane fiber (44 dtex, Mobilon (registered trademark, manufactured by Nisshinbo Textile Co., Ltd.) R) Was used to perform milling with a circular knitting machine. The mixing ratio of the fibers was 80.7% by mass for silver-plated fibers and 19.3% by mass for polyurethane fibers. The degree was 40 courses / 0.5 inches and 30 wales / 0.5 inches. The obtained fiber knitted fabric is scoured (treated at 60 ° C. for 10 minutes), washed with water (5 minutes), dehydrated (3 minutes with a dehydrator), and dried (1 at 80 ° C.) using a treatment solution of 1 g / L of a scouring agent. Time) and fabric finishing (fixed to a mold and subjected to 130 ° C. (wet heat) for 10 minutes) to produce an electrode layer (thickness t in Table 1) composed of a fiber knitted fabric (knit).

(Examples 2, 4-6, 9, 10, Comparative Example 1)
In Example 1, a fiber knitted fabric (knit) was made in the same manner as in Example 1 except that a tentacle knitting was used instead of the milling knitting, and the thickness of the electrode layer was set to the thickness t shown in Table 1. The electrode layer comprised by this was manufactured.

(Examples 3, 7, 8, and 11)
As the electrode layer, a film (thickness t = 0.1 mm) printed with a silver paste on a urethane film (Esmer URS manufactured by Nippon Matai Co., Ltd.) was used.

<Manufacture of bioelectrode>
Next, an uneven layer formed of acrylic resin is placed on one surface of each electrode layer prepared above so that the uneven shape is on the electrode layer side (the back side is a flat surface), and an adhesive (silyl Adhesive polyurethane). The concavo-convex shape of the concavo-convex layer is formed by a plurality of convex portions and concave portions located between the convex portions, as shown in the schematic diagrams of FIGS. 4 and 5, and each convex portion is a quadrangular pyramid.

  About each uneven | corrugated layer used in Examples 1-11, thickness d of an uneven | corrugated layer, the height h of a convex part, the distance w between adjacent convex parts, the height h of the convex part of an uneven | corrugated layer, and the thickness t of an electrode layer Table 1 shows the difference (h−t), the cross-sectional angle θ of the tip of the convex portion, the microhardness of the convex portion, and the Asker C hardness of the convex portion. In Comparative Example 1, a layer (thickness: 3.0 mm) formed of an acrylic resin having no uneven shape was disposed. Moreover, the microhardness of the convex part of an uneven | corrugated layer and the Asker C hardness of a convex part are the values measured by the below-mentioned method, respectively.

  Next, a urethane film (Esmer (registered trademark, manufactured by Nihon Matai Co., Ltd.) # 5, 50 μm) is laminated on the back side of the concavo-convex layer and hot pressed (180 ° C., 10 MPa for 30 seconds) to form a moisture permeation suppression layer. Formed. The obtained laminate was immersed in a fluorine-based hydrophobic surface treatment solution and subjected to heat treatment (150 ° C., 2 minutes) to form a hydrophobic treatment layer on the surface of the electrode layer. Next, on the urethane film side of the laminate, a urethane nonwoven fabric (Espancione (registered trademark, manufactured by KB Selen Co., Ltd.) UEO-50, thickness 120 μm) as an adhesive layer and neoprene rubber (thickness 4 mm) as a base material layer ) Were laminated and thermocompression bonded (140 ° C., 0.5 MPa for 1 minute) to obtain each bioelectrode. In addition, the thickness of each layer of the obtained bioelectrode was 0.1 mm for the moisture permeation suppression layer and 2 mm for the base material layer. The thicknesses of the electrode layers and the uneven layers are as shown in Table 1.

(Measurement of micro hardness)
It measured using the microhardness meter based on the prescription | regulation of ISO 14577-1. As the micro hardness tester, a dynamic ultra micro hardness tester “DUH-211S” manufactured by Shimadzu Corporation was used. The load speed (test speed) was 0.15 mN / sec, the holding time was 2 seconds, the indentation depth was 10 μm, and the indenter was a triangular pan indenter (angle between ridges 115 degrees).

(Measurement of Asker C hardness)
In accordance with the regulations of SRIS0101, measurement was performed using an Asker rubber hardness tester C type. Since the uneven | corrugated layer used by the Example and the comparative example was less than 1 cm in thickness, it measured by overlapping so that an uneven | corrugated layer might be 1 cm or more.

<Electrocardiogram measurement>
Each biological electrode obtained as described above was attached to the body surface (upper part of the heart) of the subject so that the applied pressure was 1 kPa. The bioelectrode is connected to the electrocardiograph via wiring. Next, an electrocardiogram waveform (electrocardiogram) at rest and walking (speed 5 km / h, measurement period 1 minute) was obtained using a treadmill in an environment of room temperature 15 ° C. and humidity 40% RH. The acquisition accuracy of the electrocardiographic waveform during the measurement period was evaluated according to the following criteria. The results are shown in Table 1. The electrocardiographic waveforms at rest and during walking in Example 1 and Comparative Example 1 are shown in FIGS. FIG. 6 shows a state in which an electrocardiographic waveform is measured by using the bioelectrode of Example 1 and the electrocardiographic waveform changes during walking from stationary. FIG. 7 shows a state in which an electrocardiographic waveform is measured by using the bioelectrode of Comparative Example 1 and the electrocardiographic waveform is changed from a stationary state to a walking state.

(Evaluation criteria)
A. The electrocardiogram waveform is clear and the electrocardiogram waveform can be acquired with high accuracy.
B. Although the artifact noise is slightly mixed in the ECG waveform, the ECG waveform can be acquired.
C. A lot of artifact noise is mixed in the ECG waveform, and the accuracy of the acquired ECG waveform is low.
D. The electrocardiogram waveform contains a lot of artifact noise, and the electrocardiogram waveform cannot be acquired.

The annotations in Table 1 are as follows.
* 1 In Comparative Example 1, it is the thickness of a layer formed of an acrylic resin that does not have an uneven shape.

DESCRIPTION OF SYMBOLS 1 Electrode layer 2 Base material layer 3 Moisture permeation suppression layer 4 Adhesive layer 5 Concavity and convexity layer 10 Bioelectrode

Claims (10)

  A biological electrode comprising a laminate in which at least an uneven layer having an uneven shape and an electrode layer are stacked.   The biological electrode according to claim 1, wherein the height h of the convex portion of the concave-convex layer is 0.1 mm or more.   The biological electrode according to claim 1 or 2, wherein the thickness t of the electrode layer is 8 mm or less.   The bioelectrode according to any one of claims 1 to 3, wherein a difference (ht) between a height h of the convex portion of the concave-convex layer and a thickness t of the electrode layer is 0.01 to 8 mm. Microhardness of the convex portion of the concavo-convex layer is 0.01~30N / mm ^2, the biological electrode according to any of claims 1 to 4.   The biological electrode according to any one of claims 1 to 5, wherein when the concavo-convex layer is observed from a direction perpendicular to the stacking direction of the stacked body, the shape of the convex portion is a triangle, a quadrangle, or a semicircle.   The bioelectrode according to any one of claims 1 to 6, wherein the electrode layer is composed of a fiber knitted fabric or a conductive resin film.   A biological electrode comprising an electrode layer having an uneven shape.   The biological electrode according to claim 1, wherein the electrode layer is provided on the base material layer.   A fabric to which the bioelectrode according to any one of claims 1 to 9 is fixed.