JP2018042718A - Bioelectrode - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bioelectrode by which a bioelectric signal can be acquired accurately even in a situation in which artifact tends to be taken into a bioelectric signal, such as a situation in which a body motion is large.SOLUTION: A bioelectrode includes an electrode layer composed of fiber knitted fabric whose surface roughness (Ra) is 40 μm or less. The fiber kitted fabric includes a conductive fiber and a thermal fusion fiber or a heat coalescing fiber. The conductive fiber and the thermal fusion fiber or the heat coalescing fiber are bonded to each other.SELECTED DRAWING: None

Description

  The present invention relates to a bioelectrode and a fabric including the same. More specifically, the present invention relates to a bioelectrode provided with an electrode layer composed of a fiber knitted fabric, and a fabric on which the bioelectrode is fixed.

  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.

  In view of the above-described problems of the prior art, the present invention provides a bioelectrode capable of acquiring a bioelectric signal with high accuracy even in a situation where artifacts are easily captured in the bioelectric signal, such as a situation where body motion is large. Is the main purpose.

  As a result of intensive studies in view of the above-mentioned problems, the present inventors have an electrode layer composed of a fiber knitted fabric, and a bioelectrode having a surface roughness (Ra) of the fiber knitted fabric of 40 μm or less is provided. The present inventors have also found that bioelectric signals can be obtained with high accuracy even in situations where artifacts are likely to be incorporated into bioelectric signals, such as situations where body motion is large. 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. It has an electrode layer composed of fiber knitted fabric,
The biological electrode whose surface roughness (Ra) of the said fiber knitted fabric is 40 micrometers or less.
Item 2. The fiber knitted fabric includes conductive fibers, heat-fusible fibers or heat-bonding fibers,
Item 2. The bioelectrode according to Item 1, wherein the conductive fiber and the heat-fusible fiber or the heat-bonding fiber are combined.
Item 3. Item 3. The biological electrode according to Item 1 or 2, wherein the electrode layer is provided on the base material layer.
Item 4. Item 4. The biological electrode according to Item 3, comprising a moisture permeation suppression layer between the electrode layer and the base material layer.
Item 5. Item 5. A fabric in which the bioelectrode according to any one of Items 1 to 4 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 with high accuracy even in a situation where artifacts are likely to be captured in a bioelectric signal such as a situation where body movement is large. A bioelectrode 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. 2 is an electrocardiogram waveform during walking in Example 1. FIG. 2 is an electrocardiogram waveform during jogging in Example 1; 6 is an electrocardiogram waveform during walking in Comparative Example 1. 6 is an electrocardiogram waveform during jogging in Comparative Example 1;

  The bioelectrode of the present invention includes an electrode layer composed of a fiber knitted fabric, and the surface roughness (Ra) of the fiber knitted fabric is 40 μm or less. 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 as shown in FIG. The electrode layer is composed of a fiber knitted fabric.

  The fiber knitted fabric constituting the electrode layer has electrical conductivity. 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 a fiber made of a metal such as silver, nickel, copper, iron, tin, or an alloy 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.

  In the bioelectrode of the present invention, the surface roughness (Ra) of the fiber knitted fabric is 40 μm or less. In the present invention, the surface roughness (Ra) of the surface of the fiber knitted fabric constituting the electrode layer has such a small value, and since the surface smoothness is very high, the body movement is large. Even in a situation where artifacts are likely to be captured in the bioelectric signal, such as the situation, the bioelectric signal can be acquired with high accuracy. More specifically, the bioelectrode of the present invention has very high surface smoothness on the surface of the electrode layer, and therefore has high adhesion to the skin. As a result, the contact impedance between the skin and the electrode layer is reduced, and as a result, artifacts are hardly taken into the bioelectric signal, and the bioelectric signal can be obtained with high accuracy. Further, even if the body movement is not large, for example, even in a situation where it is difficult to sweat, artifacts are easily taken into the bioelectric signal, but the bioelectrode of the present invention has high adhesion to the skin, so Artifacts are less likely to be captured, and bioelectric signals can be acquired with high accuracy.

  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.

  From the viewpoint of obtaining bioelectric signals with higher accuracy, the surface roughness (Ra) on the surface of the fiber knitted fabric is preferably 35 μm or less, more preferably 30 μm or less, and even more preferably 26 μm or less. From the same viewpoint, the surface roughness (Ra) is preferably 10 μm or more.

  The surface roughness (Ra) on the surface of the fiber knitted fabric is a value measured by a method in accordance with the provisions of JIS B0601-2001, and more specifically, a value measured by the method described in the examples.

  The method for setting the surface roughness (Ra) on the surface of the fiber knitted fabric to 40 μm or less is not particularly limited. For example, the fiber knitted fabric is subjected to a hot press, and the conductive fibers and the heat-bonded fibers are combined. The method of letting it be mentioned. As described above, when the fiber knitted fabric includes conductive fibers, heat-bonded fibers, and the like, the surface smoothness of the fiber knitted fabric can be effectively increased by hot pressing, and the surface roughness (Ra) is suitably set. It can be set to 40 μm or less.

  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. More specifically, the water contact angle on the surface of the fiber knitted fabric is preferably 115 ° or more or 85 ° or less.

  For example, the water contact angle on the surface of the fiber knitted fabric constituting the electrode layer has a high hydrophobicity of 115 ° or more, so that even in a situation where artifacts are easily taken into the bioelectric signal, it is even higher. A bioelectric signal can be acquired with high accuracy. More specifically, 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 system which acquires a bioelectric signal improves.

  On the other hand, even when the water contact angle on the surface of the fiber knitted fabric constituting the electrode layer has a high hydrophilicity of 85 ° or less, it is even higher in a situation where artifacts are easily taken into the bioelectric signal. A bioelectric signal can be acquired with high accuracy. More specifically, 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 captured in the bioelectric signal, and the bioelectric signal acquisition system is improved.

  When the fiber knitted fabric has a hydrophobic surface, the water contact angle on the surface of the fiber knitted fabric is preferably 120 ° or more, more preferably 130 ° or more, from the viewpoint of obtaining a bioelectric signal with higher accuracy. From the same viewpoint, the water contact angle is preferably 150 ° or less. On the other hand, when the surface of the fiber knitted fabric is a hydrophilic surface, the water contact angle on the surface of the fiber knitted fabric is preferably 80 ° or less, more preferably 75 ° from the viewpoint of obtaining a bioelectric signal with higher accuracy. The following are mentioned. From the same viewpoint, the water contact angle is preferably 50 ° or more. In addition, the measurement method of the said water contact angle is the value measured using the automatic contact angle meter based on prescription | regulation of JISR3257.

  The method for setting the water contact angle on the surface of the fiber knitted fabric to 115 ° or more is not particularly limited, for example, a method using a highly hydrophobic material such as the above-described conductive fiber or heat-sealed fiber, The method of providing a hydrophobic treatment layer on the surface of a fiber knitted fabric is mentioned. Among these, the method of providing a hydrophobic treatment layer on the surface of the fiber knitted fabric is preferable from the viewpoint of obtaining bioelectric signals with higher accuracy.

  The method of providing the hydrophobic treatment layer on the surface of the fiber knitted fabric is not particularly limited, and examples thereof include a method of immersing the fiber knitted fabric in the hydrophobic surface treatment liquid. By this method, it becomes possible to form a hydrophobic treatment layer uniformly on the fiber surface constituting the fiber knitted fabric, and the hydrophobicity can be efficiently increased. 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.

  On the other hand, the method for setting the water contact angle on the surface of the fiber knitted fabric to 85 ° or less is not particularly limited. For example, a method using a highly hydrophilic material such as the above-described conductive fiber or heat-sealed fiber. And a method of providing a hydrophilic treatment layer on the surface of the fiber knitted fabric. Among these, a method of providing a hydrophilic treatment layer on the surface of the fiber knitted fabric is preferable from the viewpoint of obtaining a bioelectric signal with higher accuracy.

  The method for providing the hydrophilic treatment layer on the surface of the fiber knitted fabric is not particularly limited, and examples thereof include a method of immersing the fiber knitted fabric in the hydrophilic surface treatment liquid. By this method, it becomes possible to form a hydrophilic treatment layer uniformly on the surface of the fiber constituting the fiber knitted fabric, and the hydrophilicity can be efficiently increased. 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 of the electrode layer is not particularly limited, and for example, about 10 to 1,000 μm, and more preferably about 30 to 800 μm.

  In the bioelectrode of the present invention, for example, as shown in FIG. 1, 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. There may be one kind of material constituting the base material layer, or two or more kinds. From the viewpoint of improving the adhesion of the bioelectrode to the skin, when the base material layer is made of resin, the resin is preferably sponge-like.

  The base material layer may be a single layer or a multilayer. Moreover, when a base material layer 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 a base material layer, 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 about 0.1-10 mm. More preferably, about 1-8 mm is mentioned.

  In the bioelectrode of the present invention, for example, as shown in FIG. 1, 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 makes it possible to more efficiently retain moisture released from the skin between the skin and the electrode layer surface. The signal can be acquired with higher accuracy.

  The moisture permeation suppression layer is not particularly limited as long as it can suppress the moisture 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 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 may be a single layer or a multilayer. Moreover, when the moisture permeation suppression layer is a multilayer, the materials constituting each layer may be the same or different.

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

  The thickness of the moisture permeation suppression layer is not particularly limited, and is, for example, about 1 to 500 μm, more preferably about 10 to 200 μm.

  The method for laminating the electrode 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 the electrode layer and the base material layer are bonded by hot pressing, it is preferable to perform hot pressing under conditions of a temperature of about 80 to 200 ° C., a pressure of about 0.05 to 20 MPa, and about 1 to 60 seconds. When the electrode layer and the moisture permeation suppression layer are bonded by hot pressing, it is preferable to perform hot pressing under conditions of a temperature of about 80 to 200 ° C., a pressure of about 0.01 to 10 MPa, and a time of about 5 to 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 such as a modified silicone polymer. 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.

  Since the electrode layer of the bioelectrode of the present invention is constituted by a fiber knitted fabric, for example, unlike a conventional bioelectrode using an electroconductive adhesive layer as an electrode, it can be repeatedly washed and used. In addition, 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 placed between them and thermocompression bonded, or an adhesive may be used. And 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.

  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.

Example 1
Using silver plated fibers (nylon multifilament [trade name: AGposs] manufactured by Mitsuji Fuji Textile Co., Ltd.) 78 dtex / 34f and polyurethane fibers (44 dtex, Mobilon (registered trademark, manufactured by Nisshinbo Textile Co., Ltd.) R), Milling was performed with a 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 700 μm) constituted by a fiber knitted fabric.

  Next, a urethane film (Esmer (registered trademark, manufactured by Nihon Matai Co., Ltd.) # 5, 50 μm) is laminated on one surface of the obtained electrode layer, and hot pressing is performed at each temperature shown in Table 1 (30 at 1 MPa). Second) to form a moisture permeation suppressing layer. 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 a bioelectrode. In addition, the thickness of each layer of the obtained bioelectrode was 550 μm for the electrode layer, 45 μm for the moisture permeation suppression layer, and 4 mm for the base material layer. Moreover, it was 138.5 degrees when the water contact angle of the electrode layer surface was measured by the method of the below-mentioned.

(Example 2)
In the formation of the electrode layer of Example 1, the mixing ratio of fibers was 85.2% by mass of silver-plated fibers and 14.8% by mass of polyurethane, and the course was 50 course / 0.5 inch, 26 wales / 0.5 inch. A bioelectrode was obtained in the same manner as in Example 1 except that.

(Example 3)
In the formation of the electrode layer of Example 1, the mixing ratio of the fibers was 61.5% by mass of silver-plated fibers and 38.5% by mass of polyurethane, and the degree was 36 courses / 0.5 inches and 25 wales / 0.5 inches. A bioelectrode was obtained in the same manner as in Example 1 except that.

Example 4
In the formation of the electrode layer of Example 1, the mixing ratio of the fibers was 67.7% by mass of silver-plated fibers and 32.3% by mass of polyurethane, and the degree was 40 courses / 0.5 inches and 25 wales / 0.5 inches. A bioelectrode was obtained in the same manner as in Example 1 except that.

(Comparative Example 1)
In Example 1, a bioelectrode was obtained in the same manner as Example 1 except that no heat pressing was performed. In Table 2, “no hot pressing” means that an adhesive (main component: modified silicone polymer, thickness: 60 μm) was used in the lamination of the electrode layer and the moisture permeation suppression layer without performing hot pressing. To do.

(Comparative Example 2)
In Example 2, a bioelectrode was obtained in the same manner as Example 2 except that no heat pressing was performed.

(Comparative Example 3)
In Example 3, a bioelectrode was obtained in the same manner as in Example 3 except that no heat pressing was performed.

(Comparative Example 4)
In Example 4, a bioelectrode was obtained in the same manner as Example 4 except that no heat pressing was performed.

<Measurement of surface roughness (Ra)>
The surface roughness (Ra) of the electrode layer surface of each bioelectrode obtained in Examples 1 to 4 and Comparative Examples 1 to 4 was measured according to the provisions of JIS B0601-2001, respectively. For measurement, a VK-9700 (objective lens 10 times) manufactured by Keyence Corporation was used as a laser microscope. The results are shown in Tables 1 and 2.

<Measurement of water contact angle>
The water contact angle of the electrode layer surface of each bioelectrode obtained in Examples 1 to 4 and Comparative Examples 1 to 4 is based on the provisions of JIS R3257, and an automatic contact angle meter (DSA20E manufactured by KRUSS) is used. And measured. The results are shown in Table 1.

<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, in the environment of room temperature 15 ° C, humidity 40% RH, using a treadmill, walking (speed 5 km / h, measurement period 1 minute) or jogging (speed 8 km / h, measurement period 1 minute) Radio wave form (electrocardiogram) was acquired. The acquisition accuracy of the electrocardiographic waveform during the measurement period was evaluated according to the following criteria. The results are shown in Tables 1 and 2. In addition, the electrocardiogram waveform obtained when using the biopress electrode of Example 1 with a hot press temperature of 180 ° C. and Comparative Example 1 without hot press is shown in FIGS. 2 is an electrocardiogram waveform during walking in Example 1, FIG. 3 is an electrocardiogram waveform during jogging in Example 1, and FIG. 4 is an electrocardiogram waveform during walking in Comparative Example 1. FIG. 5 is an electrocardiographic waveform during jogging in Comparative Example 1.
(Evaluation criteria)
A. The electrocardiogram waveform is clear and the electrocardiogram waveform can be acquired with high accuracy.
B. Although an artifact is slightly mixed in the electrocardiogram waveform, the electrocardiogram waveform can be acquired.
C. Many artifacts are mixed in the electrocardiogram waveform, and the accuracy of the acquired electrocardiogram waveform is low.
D. There are so many artifacts in the ECG waveform that the ECG waveform cannot be acquired.

DESCRIPTION OF SYMBOLS 1 Electrode layer 2 Base material layer 3 Water permeation suppression layer 4 Adhesive layer 10 Bioelectrode

Claims (5)

It has an electrode layer composed of fiber knitted fabric,
The biological electrode whose surface roughness (Ra) of the said fiber knitted fabric is 40 micrometers or less. The fiber knitted fabric includes conductive fibers, heat-fusible fibers or heat-bonding fibers,
The bioelectrode according to claim 1, wherein the conductive fiber and the heat-fusible fiber or the heat-bonding fiber are combined.   The biological electrode according to claim 1, wherein the electrode layer is provided on a base material layer.   The biological electrode according to claim 3, further comprising a moisture permeation suppression layer between the electrode layer and the base material layer.   The fabric by which the bioelectrode in any one of Claims 1-4 is being fixed.