Bioelectrode and method for manufacturing bioelectrode

Abstract

To provide a comfortable and light-weight highly transparent thin film bioelectrode which causes no pain, red spots, rash, etc. to the skin at a low manufacturing cost whose color is only slightly different from a skin color, in which sensitivity of a biological signal is high, and biocompatibility is excellent, the sensitivity of the biological signal not being deteriorated substantially even when wetted with water or dried, and stuck to the skin for a long period, and to provide a manufacturing method thereof.SOLUTION: A bioelectrode includes: a conductive polymer composite layer, (C) a conductive layer, and (D) a base material. The conductive polymer composite layer consists of a conductive polymer composite containing (A) a π-conjugated polymer and (B) a dopant polymer. In (D) the base material, the transmissivity is 20% or more at a wavelength of 600 nm, the color is yellow red (YR) in a Munsell color system, the brightness is in the range of 1-9, and the color saturation is in the range of 1-12.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a bioelectrode and a method for manufacturing the bioelectrode. [Background technology]

[0002] In recent years, the development of wearable devices has progressed along with the spread of IoT (Internet of Things). Wearable devices that can constantly monitor physical condition are also needed in the medical and sports fields, and this is an area of ​​future growth. In particular, the global spread of the novel coronavirus (COVID-19) has placed a serious strain on medical care, and there are calls for the need for and acceleration of home medical care for people who are not infected with the virus.

[0003] In the medical field, wearable devices are commercially available that monitor the state of the body's organs by sensing weak electrical currents, such as in electrocardiograms, which detect heart activity through electrical signals. Electrocardiograms are measured by wearing electrodes coated with hydrated gel on the body, but this is a one-time, short-term measurement. In contrast, the goal of developing medical wearable devices like those mentioned above is to develop devices that can continuously monitor health status for several weeks. Therefore, bioelectrodes used in medical wearable devices must be able to collect biosignals even when used for long periods of time during daily activities such as showering, bathing, and sweating, and must be comfortable and not cause itching or skin allergies. In addition, they must be lightweight and thin enough to be unnoticeable when worn, and they must be able to be manufactured at low cost and with high productivity.

[0004] While it is now possible to measure electrocardiograms using watch-type devices such as the Apple Watch and non-contact sensing using Radar, highly accurate electrocardiogram measurements for medical use require an electrocardiograph that attaches bioelectrodes to several points on the body.

[0005] Wearable medical devices include those that are attached to the body and those that are incorporated into clothing. A widely used type of attached-to-body bioelectrode uses the above-mentioned hydrated gel material, such as the hydrophilic gel containing water and electrolytes described in Patent Document 1. The hydrophilic gel contains sodium, potassium, and calcium as electrolytes in a hydrophilic polymer that retains water, and converts changes in ion concentration from the skin into an electrical signal through a reduction reaction of silver chloride that comes into contact with the hydrophilic gel. Problems include the loss of conductivity when the gel dries, causing it to lose its function as a bioelectrode, and the problem of it swelling and peeling off during bathing or showering.

[0006] On the other hand, as a type that can be incorporated into clothing, a method has been proposed in which conductive polymers such as PEDOT-PSS (Poly-3,4-ethylenedioxythiophene-Polystyrenesulfonate) or silver paste is incorporated into the fibers of a cloth and used as an electrode (Patent Document 2).

[0007] A stretchable and highly conductive bioelectrode sheet has been developed (Non-Patent Document 1). In this sheet, silver nanowires are applied to a polyurethane film, and flash annealing is performed to instantly heat and melt the surface of the silver nanowires to 500°C or higher, fusing the silver nanowires together.

[0008] Bioelectrodes made of thin gold films or high-concentration silver nanowires are metallic in color and not transparent. If a bioelectrode could be developed that is transparent and allows the skin to be seen through, it would have the advantage of not creating a visual sense of incongruity when attached to the skin.

[0009] PEDOT-PSS is being investigated as a transparent conductive film for organic electroluminescence (EL) applications to replace ITO. A combination of silver nanowires and PEDOT-PSS has also been studied (Non-Patent Document 2). However, PEDOT-PSS exhibits a blue color, which is significantly different from the color of skin. To improve transparency and lighten the blue color, the application of polythiophene combined with a fluorine-doped dopant to transparent conductive films has been demonstrated (Patent Documents 3 to 10). [Prior art documents] [Patent documents]

[0010] [Patent Document 1] International Publication No. 2013 / 039151 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-100673 [Patent Document 3] Patent No. 6661212 [Patent Document 4] Patent No. 6450661 [Patent Document 5] Patent No. 6335138 [Patent Document 6] Patent No. 6271378 [Patent Document 7] Patent No. 6407107 [Patent Document 8] Patent No. 6496258 [Patent Document 9] Patent No. 6483518 [Patent Document 10] Patent No. 6438348 [Non-patent literature]

[0011] [Non-Patent Document 1] Nano Res.9,401(2016) [Non-patent document 2] J. Photopolymer Sci. and Tech. Vol32 No.3 p429 (2019) Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention has been made to solve the above problems, and aims to provide a bioelectrode that is thin, highly transparent, has only a slight difference in color from the skin, is highly sensitive to biosignals, has excellent biocompatibility, is lightweight, can be manufactured at low cost, does not significantly reduce the sensitivity to biosignals even when wet or dry, or when attached to the skin for a long period of time, and is comfortable to use without causing itching, redness, rashes, etc., on the skin, and a method for manufacturing the same. [Means for solving the problem]

[0013] In order to solve the above problems, the present invention provides a bioelectrode comprising a conductive polymer composite layer, (C) a conductive layer, and (D) a substrate, wherein the conductive polymer composite layer is (A) a π-conjugated polymer, and (B) a dopant polymer containing a repeating unit a having one or more repeating units selected from sulfonic acid, fluorosulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide, and having a weight-average molecular weight in the range of 1,000 to 500,000; a conductive polymer composite comprising: The bioelectrode is provided in which the (D) substrate has a transmittance of 20% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, a brightness in the range of 1 to 9, and a chroma in the range of 1 to 12.

[0014] Such a bioelectrode is thin and highly transparent, has only a slight difference in color from the skin, is highly sensitive to biosignals, has excellent biocompatibility, is lightweight, and can be manufactured at low cost.The sensitivity of biosignals does not decrease significantly even when wet or dry, or when attached to the skin for a long period of time, and it is a comfortable bioelectrode that does not cause itching, redness, or rashes on the skin.

[0015] In the present invention, the conductive layer (C) preferably contains one or more selected from gold, silver, silver chloride, platinum, aluminum, magnesium, tin, tungsten, iron, copper, nickel, stainless steel, chromium, titanium, and carbon.

[0016] The conductive layer (C) may contain such elements.

[0017] In the present invention, the repeating unit a preferably has a partial structure represented by the following general formulas (1)-1 to (1)-4. [ka] (In the general formula (1)-1, Rf1 and Rf2 are a hydrogen atom, a fluorine atom, an oxygen atom, a methyl group, or a trifluoromethyl group. When Rf1 and Rf2 are oxygen atoms, Rf1 and Rf2 are one oxygen atom that is bonded to one carbon atom to form a carbonyl group. Rf3 and Rf4 are a hydrogen atom, a fluorine atom, or a trifluoromethyl group. At least one of Rf1 to Rf4 is a fluorine atom or a trifluoromethyl group. In the general formula In (1)-2, Rf5 is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 1 to 4. In general formulas (1)-3 and (1)-4, Rf6 and Rf7 are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and have at least one fluorine atom. In general formulas (1)-1 to (1)-4, M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions.

[0018] If the repeating unit a has such a structure, the resulting bioelectrode will have better conductivity and biocompatibility.

[0019] In this case, the repeating unit a preferably has one or more repeating units selected from the repeating units A1 to A7 represented by the following general formula (2). [ka] (In general formula (2), R 1 , R 3 , R 5 , R 8 , R 10, R 11 , and R 13 are each independently a hydrogen atom or a methyl group, and R 2 , R 4 , R 6 , R 9 , R 12 , and R 14 are each independently a single bond or a linear, branched or cyclic hydrocarbon group having 1 to 13 carbon atoms. The hydrocarbon group may have an ester group, an ether group, or both. R 7 is a linear or branched alkylene group having 1 to 4 carbon atoms, and R 7 One or two of the hydrogen atoms in X1, X2, X3, X4, X6, and X7 may be substituted with a fluorine atom. Each of X1, X2, X3, X4, X6, and X7 independently represents a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, or an amide group, and X5 represents a single bond, an ether group, or an ester group. Y represents an oxygen atom or -NR 19 - group. 19 is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, or a phenyl group, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, and an amide group. 4 may form a ring together with Rf1' and Rf5'. Rf1' and Rf5' are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms and having at least one fluorine atom. m is an integer of 1 to 4. a1, a2, a3, a4, a5, a6, and a7 are each 0≦a1≦1.0, 0≦a2≦1.0, 0≦a3≦1.0, 0≦a4≦1.0, 0≦a5≦1.0, 0≦a6≦1.0, and 0≦a7≦1.0, and <a1+a2+a3+a4+a5+a6+a7≦1.0である。M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions.

[0020] If the repeating unit a has such a structure, the resulting bioelectrode will have even better conductivity and biocompatibility.

[0021] In this case, the repeating unit a preferably contains an ammonium ion represented by the following general formula (3) as the ammonium ion constituting the ammonium salt. [ka] (In general formula (3), R 101d , R 101e , R 101f and R 101g R are each a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 15 carbon atoms, a linear, branched, or cyclic alkenyl or alkynyl group having 2 to 12 carbon atoms, or an aromatic group having 4 to 20 carbon atoms, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, a hydroxy group, a carboxy group, an amino group, a nitro group, a sulfonyl group, a sulfinyl group, a halogen atom, and a sulfur atom. 101d and R 101e , or R 101d , R 101e and R 101f may form a ring together with the nitrogen atom to which they are attached, and when they form a ring, R 101d and R 101e , or R 101d , R 101e and R 101f is an alkylene group having 3 to 10 carbon atoms, or forms a heteroaromatic ring having the nitrogen atom in the ring in general formula (3).

[0022] If the polymer compound containing such ammonium ions is included, the resulting bioelectrode will have even better conductivity and biocompatibility.

[0023] In the present invention, it is also preferable that the conductive polymer composite contains, in addition to the components (A) and (B), one or more (E) resins selected from a (meth)acrylate resin, a (meth)acrylamide resin, a urethane resin, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline, polyglycerin, polyglycerin-modified silicone, cellulose, polyethylene glycol, and polypropylene glycol.

[0024] The conductive polymer composite may contain such a resin (E).

[0025] In the present invention, it is also preferred that the (D) substrate has a transmittance of 30% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, a brightness of 1 to 9, and a chroma of 1 to 12.

[0026] Such a bioelectrode is preferable because it will have less difference with the color of the skin.

[0027] In addition, in the present invention, it is preferable that the (D) substrate has a film attached to the side of the bioelectrode that contacts the skin and / or the opposite side, the film having a transmittance of 30% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a brightness in the range of 1 to 9 and a saturation in the range of 1 to 12.

[0028] Such a bioelectrode is preferable because it can be easily produced and the difference in color with the skin color is smaller.

[0029] In the present invention, the (D) substrate preferably has an anti-reflection mechanism on the surface opposite to the side of the bioelectrode that comes into contact with the skin.

[0030] Such a bioelectrode is preferable because it reduces light reflection and has high transparency.

[0031] The present invention also provides a method for manufacturing a bioelectrode, which comprises applying a solution containing metal nanowires or printing a conductive paste containing conductive particles onto the (D) substrate, which has a transmittance of 20% or more at a wavelength of 600 nm and a yellow-red (YR) color in the Munsell color system, with a lightness of 1 to 9 and a saturation of 1 to 12, to form the (C) conductive layer, and then applying the conductive polymer composite thereon to form the conductive polymer composite layer, thereby forming the bioelectrode described above.

[0032] This method of manufacturing a bioelectrode allows for the production of a thin, highly transparent electrode that is only slightly different in color from the skin, has high sensitivity to biosignals, is biocompatible, is lightweight, and is manufactured at low cost.The sensitivity of biosignals does not decrease significantly even when wet or dry, or when attached to the skin for long periods of time, and the bioelectrode is comfortable and does not cause itching, redness, or rashes on the skin. [Effects of the Invention]

[0033] As described above, the bioelectrode of the present invention has a slight difference in color from the skin when attached to the skin, is highly sensitive to biosignals, has excellent biocompatibility, is thin, lightweight, highly transparent, and can be manufactured at low cost.The sensitivity of biosignals does not decrease significantly even when wet or dry, or when attached to the skin for a long period of time, and it is comfortable to use and does not cause itching, redness, or rashes on the skin, and a method for manufacturing the same can be provided. [Brief explanation of the drawings]

[0034] [Figure 1] FIG. 2 is a cross-sectional view of a yellow-red (YR) substrate after a conductive layer is formed on the substrate. [Figure 2] FIG. 2 is a cross-sectional view of the bioelectrode of the present invention after forming a conductive polymer composite layer on a conductive layer on a yellow-red (YR) colored substrate. [Figure 3] FIG. 1 is a cross-sectional view showing an example in which the substrate of the bioelectrode of the present invention is a composite of a yellow-red (YR) film and a transparent substrate. [Figure 4] FIG. 10 is a cross-sectional view of another example showing that the substrate of the bioelectrode of the present invention is a composite of a yellow-red (YR) film and a transparent substrate. [Figure 5] FIG. 1 is a cross-sectional view of the bioelectrode of the present invention when attached to the skin to measure a biosignal. [Figure 6] FIG. 10 is a cross-sectional view of a substrate with an anti-reflection mechanism disposed thereon. [Figure 7] FIG. 1 is a cross-sectional view of an example of a substrate having a moth-eye type anti-reflection mechanism disposed thereon. [Figure 8] FIG. 10 is a cross-sectional view of another example of a substrate having a moth-eye type anti-reflection mechanism disposed thereon. [Figure 9] FIG. 10 is a cross-sectional view of yet another example of a substrate having a moth-eye type anti-reflection mechanism disposed thereon. [Figure 10] FIG. 1 is a cross-sectional view of a substrate having a yellow-red (YR) color not only in the substrate but also in the moth-eye anti-reflection features. [Figure 11] FIG. 1 is a cross-sectional view of a transparent substrate having a moth-eye antireflection mechanism with a yellow-red (YR) color on the substrate. [Figure 12] 1 is a plan view of an example of a moth-eye type anti-reflection mechanism viewed from above. [Figure 13] 10 is another example of a plan view of a moth-eye type anti-reflection mechanism viewed from above. [Figure 14] This is a plan view of straight conductive wiring with a width of 200 μm or less formed by printing, observed from above. [Figure 15] This is a plan view of a zigzag conductive wiring pattern with a width of 200 μm or less formed by printing, observed from above. [Figure 16] This is a plan view of a conductive wiring pattern with a wavy line width of 200 μm or less formed by printing, observed from above. [Figure 17] This is a plan view of a conductive wiring pattern formed by printing, with smaller zigzags within larger zigzags, each less than 200 μm wide, observed from above. [Figure 18] This is a plan view of conductive wiring in a diagonal grid pattern with a width of 200 μm or less formed by printing, observed from above. [Figure 19] This is a top view of a hexagonal pattern of conductive wiring less than 200 μm wide formed by printing. [Figure 20] This is a plan view of a conductive wiring consisting of an array of circles with a width of 200 μm or less, formed by printing. [Figure 21] This is a plan view of a conductive wiring formed by printing, in which circles with a width of 200 μm or less are arranged in a different shape. [Figure 22] This is a plan view of conductive wiring with a mesh pattern of less than 200 μm in width formed by printing, observed from above. [Figure 23] FIG. 2 is a plan view of a conductive layer formed by applying a solution containing metal nanowires, as observed from above. [Figure 24] 1 is a cross-sectional view of a bioelectrode of the present invention after a conductive polymer composite layer is formed on a conductive layer formed on a substrate having a moth-eye type anti-reflection mechanism on both sides. [Figure 25] 1A and 1B are diagrams showing the configuration of a bioelectrode according to an embodiment. [Figure 26] 1 shows the attachment positions of bioelectrodes in biosignal measurement in an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0035] As described above, there was a need for the development of a lightweight, thin-film bioelectrode that blends in color with the skin when attached, has high conductivity and excellent biocompatibility to generate highly sensitive and low-noise biosignals, can be manufactured at low cost, can measure biosignals whether wet or dry, and does not cause skin irritation or itching even when attached to the skin for long periods of time.

[0036] As a result of extensive research into the above-mentioned problems, the present inventors have discovered a bioelectrode having the following configuration and a method for manufacturing the same, and have completed the present invention.

[0037] That is, the present invention provides a bioelectrode comprising a conductive polymer composite layer, (C) a conductive layer, and (D) a substrate, wherein the conductive polymer composite layer is (A) a π-conjugated polymer, and (B) a dopant polymer containing a repeating unit a having one or more repeating units selected from sulfonic acid, fluorosulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide, and having a weight-average molecular weight in the range of 1,000 to 500,000; a conductive polymer composite comprising: In the bioelectrode, the (D) substrate has a transmittance of 20% or more at a wavelength of 600 nm, and is yellow-red (YR) in the Munsell color system, with a brightness in the range of 1-9 and a saturation in the range of 1-12.

[0038] The present invention will be described in detail below, but the present invention is not limited thereto.

[0039] <Bioelectrode> The bioelectrode of the present invention comprises a conductive polymer composite layer, (C) a conductive layer, and (D) a substrate, wherein the conductive polymer composite layer is made of a conductive polymer composite containing (A) a π-conjugated polymer and (B) a dopant polymer containing a repeating unit a having one or more selected from sulfonic acid, fluorosulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide, and having a weight-average molecular weight in the range of 1,000 to 500,000, and the (D) substrate has a transmittance of 20% or more at a wavelength of 600 nm, and is a yellow-red (YR) color in the Munsell color system, with a lightness of 1 to 9 and a saturation of 1 to 12.

[0040] Such a bioelectrode is thin and highly transparent, has only a slight difference in color from the skin, is highly sensitive to biosignals, has excellent biocompatibility, is lightweight, and can be manufactured at low cost.The sensitivity of biosignals does not decrease significantly even when wet or dry, or when attached to the skin for a long period of time, and it is a comfortable bioelectrode that does not cause itching, redness, or rashes on the skin.

[0041] One way to make bioelectrodes blend in with the skin when attached is to match the color of the base material to the skin color of the person to whom they are attached. However, human skin color varies depending on race, age, gender, and individual, making it difficult to provide bioelectrodes of exactly the same color.

[0042] Polythiophene-based conductive polymer films are light blue. In particular, PEDOT-PSS, which uses polystyrene sulfonate as a dopant, has a pronounced blue color. Bioelectrodes coated with PEDOT-PSS have a blue color even though the conductive film and substrate are transparent, which creates a visual discomfort when applied to the skin.

[0043] [(D) Base material] For example, a skin tone with a Munsell value of 5YR8 / 5 can be created by mixing a light orange (yellow-red (YR) color) with a slight blue tint, which has a higher brightness. When blue is added to orange, the brightness and chroma decrease, thereby expressing skin tones. In the present invention, a polythiophene-based blue color is used in combination with a light orange color to create skin tones.

[0044] That is, in the present invention, the (D) substrate has a transmittance of 20% or more at a wavelength of 600 nm, is yellow-red (YR) in the Munsell color system, and has a lightness of 1 to 9 and a saturation of 1 to 12. If the transmittance at a wavelength of 600 nm is less than 20%, the difference between the skin color and the color of the bioelectrode will be large, which is undesirable. If the lightness is outside the above range, the difference between the skin color and the color of the bioelectrode will be large, which is undesirable. If the saturation is outside the above range, the difference between the skin color and the color of the bioelectrode will be large, which is undesirable. If the lightness and saturation are within the above ranges, low values ​​can represent black or brown skin colors, and high values ​​can represent white skin colors. The transmittance is a value measured with a transmittance meter.

[0045] The bioelectrode of the present invention preferably comprises a light orange substrate, a transparent conductive layer provided thereon, and a light blue conductive polymer composite layer provided on the conductive layer.

[0046] The (D) substrate itself may be light orange, or a transparent substrate with a light orange film attached thereto may be used as the (D) substrate. The orange film may be attached to either the skin side or the opposite side.

[0047] That is, it is preferable that the (D) substrate has a transmittance of 30% or more at a wavelength of 600 nm, is yellow-red (YR) in the Munsell color system, has a lightness in the range of 1 to 9, and a saturation in the range of 1 to 12, and it is preferable that the (D) substrate has a film attached to the side of the bioelectrode that comes into contact with the skin and / or the opposite side thereof, the film having a transmittance of 30% or more at a wavelength of 600 nm, is yellow-red (YR) in the Munsell color system, has a lightness in the range of 1 to 9, and a saturation in the range of 1 to 12.

[0048] Furthermore, to accommodate various skin colors, it is preferable to increase the transparency of the bioelectrode so that the skin can be seen through it. This reduces the sense of incongruity even if the color of the bioelectrode differs slightly from the actual skin color.

[0049] Light reflection may be observed on the surface of the substrate opposite the side that is attached to the skin. Since light reflection on the skin is particularly low in the blue region, it is preferable to reduce light reflection on the bioelectrode. One way to reduce light reflection is to provide an anti-reflection mechanism on the surface of the substrate. That is, it is preferable that the (D) substrate has an anti-reflection mechanism on the surface opposite the side that contacts the skin of the bioelectrode. Figure 6 shows a layered mechanism type anti-reflection mechanism. A layer with a lower refractive index than this is provided in the substrate. Although Figure 6 shows a single anti-reflection mechanism layer, the anti-reflection effect can be enhanced by providing multiple anti-reflection mechanisms with a refractive index that gradually decreases on the air layer side.

[0050] It is also possible to provide a moth-eye type antireflection mechanism having the cross-sectional views shown in Figures 7 to 9. The moth-eye type can provide a higher antireflection effect than the laminated mechanism type.

[0051] It is also possible to provide a moth-eye type anti-reflection mechanism having an orange color on a flat substrate as shown in the cross-sectional view of Fig. 10. It is also possible to provide a moth-eye type anti-reflection mechanism having an orange color on a transparent substrate as shown in the cross-sectional view of Fig. 11.

[0052] Sodium, potassium, and calcium ions are released from the skin surface in tandem with the heartbeat. Bioelectrodes must convert the increase or decrease in the ions released from the skin into an electrical signal. To do this, materials with excellent ionic conductivity are required to transmit the increase or decrease in ions. The potential on the skin surface also fluctuates in tandem with the heartbeat. This potential fluctuation is slight, so electronic conductivity is also required to transmit a weak current to the device.

[0053] Hydrophilic gels containing sodium chloride or potassium chloride have high ionic and electronic conductivity, but lose their conductivity when the water dries. Furthermore, conductivity also decreases when sodium chloride or potassium chloride leaches out of the bioelectrode during bathing or showering.

[0054] Bioelectrodes made of metals such as gold and silver can only detect weak currents and have low ionic conductivity, resulting in low sensitivity as a bioelectrode. Carbon has the same electronic conductivity as metals, but its electronic conductivity is lower than that of metals, resulting in even lower sensitivity as a bioelectrode.

[0055] Conductive polymers such as PEDOT-PSS have both electronic and ionic conductivity, but their ionic conductivity is low due to their low polarization. Furthermore, a layer coated with PEDOT-PSS has absorption in the red region, resulting in a complementary blue color. A bioelectrode that combines an orange substrate with a PEDOT-PSS-coated layer results in a slightly brownish wheat-colored bioelectrode.

[0056] The combination of a fluorine-containing dopant polymer and a π-conjugated polymer has high transparency in visible light and produces a film with a lighter blue color than PEDOT-PSS. By combining this with a light orange substrate, it can be used for whiter skin tones. Furthermore, by combining it with an orange color with low saturation and brightness, it is possible to reproduce tan and brown skin tones, making it applicable to a variety of skin tones.

[0057] Salts of sulfonic acid, fluorosulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide are highly polarizable and have high ionic conductivity. By combining these dopant polymers with π-conjugated polymers such as polythiophene, both high ionic and electronic conductivity can be achieved.

[0058] Although the main solvent for the composite of the dopant polymer and the π-conjugated polymer (conductive polymer composite) is water, it is not dissolved in water but is dispersed in the form of particles. Therefore, the conductive polymer composite layer formed by coating, baking, and drying the composite does not dissolve in water and has high water resistance. Therefore, it is possible to shower, bathe, or swim while wearing the bioelectrode of the present invention.

[0059] [(C) Conductive layer] The conductive polymer composite layer is in contact with the conductive layer (C), which transmits a biological signal to the device. In the present invention, the conductive layer (C) is not particularly limited, but preferably contains one or more metals selected from gold, silver, silver chloride, platinum, aluminum, magnesium, tin, tungsten, iron, copper, nickel, stainless steel, chromium, titanium, and carbon.

[0060] The conductive layer (C) is preferably transparent and has a form in which conductive wiring with a line width of 200 μm or less is connected. The conductive wiring with a line width of 200 μm or less is preferably a printed pattern made of a conductive paste containing gold, silver, copper, or nickel particles, or a fused layer of metal nanowires made of gold, silver, copper, nickel, or alloys thereof.

[0061] When forming conductive wiring with a width of 200 μm or less by printing, a conductive paste containing gold, silver, copper, or nickel particles can be used. The conductive paste preferably contains conductive particles such as gold, silver, copper, or nickel particles, as well as an organic solvent and a resin. Silver is particularly preferred as the conductive particles. The composition of the conductive paste is specifically shown in JP 2022-078861 A.

[0062] The metal nanowires are preferably made of gold, silver, copper, nickel, or alloys thereof. The metal nanowires preferably have a diameter of 1 to 200 nm and a length of 1 to 500 μm, and the conductive layer is preferably formed by applying and fusing a solution of the metal nanowires dispersed in an organic solvent such as water or alcohol.

[0063] The bioelectrode of the present invention can be attached anywhere on the skin of the body. It can be attached to, for example, the chest, abdomen, shoulders, arms, legs, face, scalp, etc., and can measure not only electrocardiograms but also electromyograms, brain waves, and respiratory rate. In addition to measuring signals emitted from the skin, it can also transmit signals to muscles and control brain waves by applying electrical signals to the skin. For example, it can be used to stimulate muscles during swimming to improve performance and reduce fatigue, or to enhance relaxation during bathing.

[0064] To construct a highly sensitive bioelectrode, not only high ionic conductivity but also high electronic conductivity is required. Electronic conductivity is ensured by π-conjugated polymers, but to further enhance this, it is effective to add metal powder or carbon powder to the conductive polymer composite.

[0065] <Conductive polymer composite> Each component of the conductive polymer composite that forms the conductive polymer composite layer of the bioelectrode of the present invention will be described in more detail below.

[0066] [(A) π-conjugated polymer] The component (A) of the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention may be a polymer (π-conjugated polymer) of precursor monomers (organic monomer molecules) that form a π-conjugated chain (a structure in which single bonds and double bonds are alternately connected). Examples of such precursor monomers include thiophenes, and homopolymers or copolymers of these monomers can be used as component (A).

[0067] Furthermore, even if the monomers constituting the π-conjugated polymer are unsubstituted, the component (A) can have sufficient conductivity. However, to further enhance the conductivity, a monomer substituted with an alkyl group, a carboxy group, a sulfo group, an alkoxy group, a hydroxy group, a cyano group, a halogen atom, or the like may be used.

[0068] Specific examples of thiophenes include thiophene, 3-methylthiophene, 3-ethylthiophene, 3-propylthiophene, 3-butylthiophene, 3-hexylthiophene, 3-heptylthiophene, 3-octylthiophene, 3-decylthiophene, 3-dodecylthiophene, 3-octadecylthiophene, 3-bromothiophene, 3-chlorothiophene, 3-iodothiophene, 3-cyanothiophene, 3-phenylthiophene, 3,4-dimethylthiophene, 3,4-dibutylthiophene, 3-hydroxythiophene, 3-methoxythiophene, 3-ethoxythiophene, 3-butoxythiophene, 3-hexyloxythiophene, 3-heptyloxythiophene, 3-octyloxythiophene, 3-decyloxythiophene, 3-dodecyloxythiophene, 3-octadecyl ... Examples of thiophene include decyloxythiophene, 3,4-dihydroxythiophene, 3,4-dimethoxythiophene, 3,4-diethoxythiophene, 3,4-dipropoxythiophene, 3,4-dibutoxythiophene, 3,4-dihexyloxythiophene, 3,4-diheptyloxythiophene, 3,4-dioctyloxythiophene, 3,4-didecyloxythiophene, 3,4-didodecyloxythiophene, 3,4-ethylenedioxythiophene, 3,4-propylenedioxythiophene, 3,4-butenedioxythiophene, 3-methyl-4-methoxythiophene, 3-methyl-4-ethoxythiophene, 3-carboxythiophene, 3-methyl-4-carboxythiophene, 3-methyl-4-carboxyethylthiophene, and 3-methyl-4-carboxybutylthiophene.

[0069] Among these, a (co)polymer composed of one or two selected from 3-methylthiophene, 3-methoxythiophene, and 3,4-ethylenedioxythiophene is preferably used in terms of resistance value and reactivity.

[0070] For practical reasons, the number of repeating units (precursor monomers) in component (A) in the present invention is preferably in the range of 2-20, and more preferably in the range of 6-15. The molecular weight of component (A) is preferably about 130 to 5000. The molecular weight is a value measured by gel permeation chromatography (GPC) using the weight average molecular weight (Mw) converted into polystyrene.

[0071] [(B) Dopant polymer (salt)] The dopant polymer (B) of the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention contains a repeating unit a having one or more repeating units selected from sulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide, and has a weight-average molecular weight in the range of 1,000 to 500,000. It may also contain a polymer having an ionic repeating unit a selected from the ammonium salt, lithium salt, sodium salt, and potassium salt of any of sulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide.

[0072] Specific examples of monomers for obtaining the repeating unit a having sulfonic acid or the ionic repeating unit a selected from ammonium salts, sodium salts, and potassium salts of sulfonic acid are given below. [ka] (In the formula, R 1 is a hydrogen atom or a methyl group, and M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions.

[0073] The repeating unit a can have a partial structure represented by the following general formulas (1)-1 to (1)-4. [ka] (In the general formula (1)-1, Rf1 and Rf2 are a hydrogen atom, a fluorine atom, an oxygen atom, a methyl group, or a trifluoromethyl group. When Rf1 and Rf2 are oxygen atoms, Rf1 and Rf2 are one oxygen atom that is bonded to one carbon atom to form a carbonyl group. Rf3 and Rf4 are a hydrogen atom, a fluorine atom, or a trifluoromethyl group. At least one of Rf1 to Rf4 is a fluorine atom or a trifluoromethyl group. In the general formula In (1)-2, Rf5 is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 1 to 4. In general formulas (1)-3 and (1)-4, Rf6 and Rf7 are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and have at least one fluorine atom. In general formulas (1)-1 to (1)-4, M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions.

[0074] The repeating unit a preferably has one or more repeating units selected from the repeating units A1 to A7 represented by the following general formula (2). [ka] (In general formula (2), R 1 , R 3 , R 5 , R 8 , R 10 , R 11 , and R 13 are each independently a hydrogen atom or a methyl group, and R 2 , R 4 , R 6 , R 9 , R 12 , and R 14are each independently a single bond or a linear, branched or cyclic hydrocarbon group having 1 to 13 carbon atoms. The hydrocarbon group may have an ester group, an ether group, or both. R 7 is a linear or branched alkylene group having 1 to 4 carbon atoms, and R 7 One or two of the hydrogen atoms in X1, X2, X3, X4, X6, and X7 may be substituted with a fluorine atom. Each of X1, X2, X3, X4, X6, and X7 independently represents a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, or an amide group, and X5 represents a single bond, an ether group, or an ester group. Y represents an oxygen atom or -NR 19 - group. 19 is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, or a phenyl group, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, and an amide group. 4 may form a ring together with Rf1' and Rf5'. Rf1' and Rf5' are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms and having at least one fluorine atom. m is an integer of 1 to 4. a1, a2, a3, a4, a5, a6, and a7 are each 0≦a1≦1.0, 0≦a2≦1.0, 0≦a3≦1.0, 0≦a4≦1.0, 0≦a5≦1.0, 0≦a6≦1.0, and 0≦a7≦1.0, and <a1+a2+a3+a4+a5+a6+a7≦1.0である。M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions.

[0075] In the above general formula (2), a1 to a7 represent the ratios of the repeating units A1 to A7, respectively.

[0076] (Repeating unit A) Of the repeating units A1 to A7 represented by the above general formula (2), specific examples of the fluorosulfonic acid or fluorosulfonate monomer for obtaining repeating units A1 to A5 are shown below.

[0077]

change

[0078]

change

[0079]

change

[0080]

change

[0081]

change

[0082]

change

[0083]

change

[0084]

change

[0085]

change

[0086]

change

[0087]

change

[0088]

change

[0089]

change

[0090]

change

[0091]

change

[0092]

change

[0093]

change

[0094]

change

[0095]

change

[0096]

change

[0097]

change

[0098] [ka]

[0099] [ka]

[0100] [ka]

[0101] Specific examples of sulfonimide or sulfonimide salt monomers for obtaining the repeating unit A6 of the above general formula are shown below.

[0102] [ka]

[0103] [ka]

[0104] [ka]

[0105] [ka]

[0106] [ka]

[0107] Specific examples of N-carbonylsulfonamide or N-carbonylsulfonamide salt monomers for obtaining the repeating unit A7 of the above general formula are shown below. [ka]

[0108] [ka]

[0109] [ka]

[0110] [ka] (In the formula, R 1 , R 3 , R 5 , R 8 , R 10 , R 11 , and R 13 is as mentioned above.)

[0111] (Repeating unit b) In addition to the repeating units A1 to A7, the (B) dopant polymer of the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention can also be copolymerized with a repeating unit b having a glyme chain to improve ionic conductivity. Specific examples of monomers for obtaining the repeating unit b having a glyme chain are listed below. Copolymerization of a repeating unit having a glyme chain can promote the movement of ions released from the skin within the dry electrode film, thereby increasing the sensitivity of the dry electrode.

[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka] (wherein R is a hydrogen atom or a methyl group).

[0116] (Repeating unit c) In addition to the repeating units A1 to A7 and b described above, the (B) dopant polymer of the conductive polymer composite used to form the conductive polymer composite layer used in the bioelectrode of the present invention can also be copolymerized with a hydrophilic repeating unit c having a hydroxy group, a carboxy group, an ammonium salt, a betaine, an amide group, a pyrrolidone, a lactone ring, a lactam ring, a sultone ring, a sulfonic acid, a sodium salt of sulfonic acid, or a potassium salt of sulfonic acid to improve conductivity. Specific examples of monomers from which the hydrophilic repeating unit c can be obtained are listed below. Copolymerizing repeating units containing these hydrophilic groups can increase sensitivity to ions released from the skin and improve the sensitivity of the dry electrode.

[0117] [ka]

[0118] [ka]

[0119] [ka] (wherein R is a hydrogen atom or a methyl group).

[0120] (Repeating unit d) The (B) dopant polymer of the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention can have a fluorine-containing repeating unit d in addition to the repeating units selected from the above A1 to A7, b, and c.

[0121] Specific examples of the monomer for obtaining the fluorine-containing repeating unit d include the following.

[0122] [ka]

[0123] [ka]

[0124] [ka]

[0125] [ka]

[0126] [ka]

[0127] [ka] (wherein R is a hydrogen atom or a methyl group).

[0128] (Repeating unit e) The (B) dopant polymer of the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention can further have a repeating unit e having a nitro group in addition to the repeating units selected from the above A1 to A7, b, c, and d.

[0129] Specific examples of the monomer from which the repeating unit e having a nitro group is obtained include the following.

[0130] [ka]

[0131] [ka]

[0132] [ka]

[0133] [ka]

[0134] [ka]

[0135] [ka] (wherein R is a hydrogen atom or a methyl group).

[0136] (Repeating unit f) The (B) dopant polymer of the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention can further have a repeating unit f having a cyano group in addition to the repeating units selected from the above A1 to A7, b, c, d, and e.

[0137] Specific examples of the monomer from which the repeating unit f having a cyano group is obtained include the following.

[0138] [ka]

[0139] [ka]

[0140] [ka] (wherein R is a hydrogen atom or a methyl group).

[0141] Furthermore, the repeating unit a preferably contains, as the ammonium ion constituting the ammonium salt, an ammonium ion (ammonium cation) represented by the following general formula (3). [ka] (In general formula (3), R 101d , R 101e , R 101f and R 101g R are each a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 15 carbon atoms, a linear, branched, or cyclic alkenyl or alkynyl group having 2 to 12 carbon atoms, or an aromatic group having 4 to 20 carbon atoms, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, a hydroxy group, a carboxy group, an amino group, a nitro group, a sulfonyl group, a sulfinyl group, a halogen atom, and a sulfur atom. 101d and R 101e , or R 101d , R 101e and R 101f may form a ring together with the nitrogen atom to which they are attached, and when they form a ring, R 101d and R 101e , or R 101d , R 101e and R 101f is an alkylene group having 3 to 10 carbon atoms, or forms a heteroaromatic ring having the nitrogen atom in the ring in general formula (3).

[0142] Specific examples of the ammonium ion represented by the general formula (3) are as follows:

[0143] [ka]

[0144]

change

[0145]

change

[0146]

change

[0147]

change

[0148]

change

[0149]

change

[0150]

change

[0151]

change

[0152]

change

[0153]

change

[0154]

change

[0155] [ka]

[0156] [ka]

[0157] [ka]

[0158] [ka]

[0159] [ka]

[0160] [ka]

[0161] [ka]

[0162] As a method for synthesizing the dopant polymer of component (B), for example, a desired monomer from among the monomers that give the repeating units A1 to A7, b, c, d, e, and f described above is polymerized by heating in an organic solvent with the addition of a radical polymerization initiator to obtain a dopant polymer (co)polymer.

[0163] Examples of the organic solvent used during polymerization include toluene, benzene, tetrahydrofuran, diethyl ether, dioxane, cyclohexane, cyclopentane, methyl ethyl ketone, and γ-butyrolactone.

[0164] Examples of the radical polymerization initiator include 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2'-azobis(2-methylpropionate), benzoyl peroxide, and lauroyl peroxide.

[0165] The reaction temperature is preferably 50 to 80°C, and the reaction time is preferably 2 to 100 hours, more preferably 5 to 20 hours.

[0166] In the dopant polymer of the component (B), the monomers that give the repeating units A1 to A7 may be one type or two or more types. When two or more types of monomers that give the repeating units A1 to A7 are used, the respective monomers may be copolymerized randomly or in blocks.

[0167] Furthermore, the monomers that give the repeating units A1 to A7, b, c, d, e, and f may be copolymerized randomly, or each may be copolymerized in a block.

[0168] When random copolymerization is performed by radical polymerization, the monomers to be copolymerized and a radical polymerization initiator are mixed and then heated to polymerize. If polymerization is initiated in the presence of a first monomer and a radical polymerization initiator, and a second monomer is subsequently added, one side of the polymer molecule will be polymerized with the first monomer, and the other side will be polymerized with the second monomer. However, in this case, the middle portion will contain a mixture of repeating units of the first and second monomers, which is different from a block copolymer. Living radical polymerization is preferably used to form block copolymers by radical polymerization.

[0169] In a living radical polymerization method called RAFT (Reversible Addition Fragmentation Chain Transfer) polymerization, the radicals at the polymer ends are always alive. By initiating polymerization with a first monomer and adding a second monomer after the first monomer is consumed, it is possible to form a diblock copolymer consisting of a block of repeating units from the first monomer and a block of repeating units from the second monomer. Alternatively, by initiating polymerization with a first monomer, adding a second monomer after the first monomer is consumed, and then adding a third monomer, it is possible to form a triblock polymer.

[0170] RAFT polymerization is characterized by the formation of narrow-dispersity polymers with narrow molecular weight distributions (dispersity). In particular, when RAFT polymerization is performed by adding the monomers all at once, polymers with even narrower molecular weight distributions can be formed. The dopant polymer of component (B) preferably has a narrow molecular weight distribution (Mw / Mn) of 1.0 to 2.0, particularly 1.0 to 1.5. A narrow distribution can prevent a decrease in the transmittance of a conductive polymer composite layer formed from a conductive polymer composite using the dopant polymer.

[0171] RAFT polymerization requires a chain transfer agent, specifically 2-cyano-2-propyl benzothioate, 4-cyano-4-phenylcarbonothioylthiopentanoic acid, 2-cyano-2-propyl dodecyl trithiocarbonate, 4-cyano-4-[(dodecylsulfanylthiocarbonyl)sulfanyl]pentanoic acid, 2-(dodecylthiocarbonothioylthio)-2-methylpropanoic acid, cyanomethyl dodecyl thiocarbonate, cyanomethylmethyl(phenyl)carbamothioate, bis(thiobenzoyl)disulfide, and bis(dodecylsulfanylthiocarbonyl)disulfide. Among these, 2-cyano-2-propyl benzothioate is particularly preferred.

[0172] The dopant polymer of component (B) has a weight-average molecular weight in the range of 1,000 to 500,000, preferably 2,000 to 200,000. If the weight-average molecular weight is less than 1,000, the heat resistance will be poor and the homogeneity of the complex solution with component (A) will be reduced. On the other hand, if the weight-average molecular weight exceeds 500,000, the conductivity will be reduced and the viscosity will increase, reducing workability and dispersibility in water and organic solvents.

[0173] In the present invention, the weight average molecular weight (Mw) is a value measured in terms of polyethylene oxide, polyethylene glycol, or polystyrene by gel permeation chromatography (GPC) using water, dimethylformamide (DMF), or tetrahydrofuran (THF) as a solvent.

[0174] As the monomer constituting the dopant polymer of component (B), a monomer having a sulfo group may be used, but a polymerization reaction may be carried out using a lithium salt, sodium salt, potassium salt, ammonium salt, or sulfonium salt of a sulfo group as a monomer, and after polymerization, the monomer may be converted to a sulfo group using an ion exchange resin. Here, the ratios of the repeating units A1 to A7, b, c, d, e, and f in the ionic material (B) are preferably 0 ≤ a1 ≤ 1.0, 0 ≤ a2 ≤ 1.0, 0 ≤ a3 ≤ 1.0, 0 ≤ a4 ≤ 1.0, 0 ≤ a5 ≤ 1.0, 0 ≤ a6 ≤ 1.0, 0 ≤ a7 ≤ 1.0, 0 < a1 + a2 + a3 + a4 + a5 + a6 + a7 ≤ 1.0, 0 ≤ b < 1.0, 0 ≤ c < 1.0, 0 ≤ d < 1.0, 0 ≤ e < 1.0, 0 ≤ f < 1.0; more preferably 0 ≤ a1 ≤ 1.0, 0 ≤ a2 ≤ 1.0, 0 ≤ a3 ≤ 1.0, 0 ≤ a4 ≤ 1.0, 0 ≤ a5 ≤ 1.0, 0 ≤ a6 ≤ 1.0, 0 ≤ a7 ≤ 1.0, 0.1 ≤ a1 + a2 + a3 + a4 + a5 + a6 + a7 ≤ 1.0, 0 ≤ b ≤ 0.8, 0 ≤ c ≤ 0.8, 0 ≤ d ≤ 0.8, 0 ≤ e ≤ 0.8, 0 ≤ f ≤ 0.8; even more preferably 0 ≤ a1 ≤ 1.0, 0 ≤ a2 ≤ 1.0, 0 ≤ a3 ≤ 1.0, 0 ≤ a4 ≤ 1.0, 0 ≤ a5 ≤ 1.0, 0 ≤ a6 ≤ 1.0, 0 ≤ a7 ≤ 1.0, 0.2 ≤ a1 + a2 + a3 + a4 + a5 + a6 + a7 ≤ 1.0, 0 ≤ b ≤ 0.7, 0 ≤ c ≤ 0.7, 0 ≤ d ≤ 0.7, 0 ≤ e ≤ 0.7, 0 ≤ f ≤ 0.7. a1 to a7, b, c, d, e, and f are the ratios of the repeating units A1 to A7 and b to f, respectively.

[0175] The conductive polymer composite that forms the conductive polymer composite layer of the biosensor of the present invention contains the π-conjugated polymer as the component (A) and the dopant polymer as the component (B) described above. The dopant polymer of the component (B) forms a composite by coordinating with the π-conjugated polymer of the component (A).

[0176] The conductive polymer composite preferably has dispersibility in water or an organic solvent, and can improve spin-coating film-forming properties and film flatness with respect to an inorganic or organic substrate (a substrate having an inorganic film or an organic film formed on the substrate surface).

[0177] (Method for producing the conductive polymer composite) The conductive polymer composite can be obtained, for example, by adding a monomer (thiophene or a derivative monomer thereof) that serves as the raw material for component (A) to an aqueous solution of component (B) or a mixed solution of component (B) in water and an organic solvent, adding an oxidizing agent and, if necessary, an oxidation catalyst, and then carrying out oxidative polymerization.

[0178] Examples of oxidizing agents and oxidation catalysts that can be used include peroxodisulfates (persulfates) such as ammonium peroxodisulfate (ammonium persulfate), sodium peroxodisulfate (sodium persulfate), and potassium peroxodisulfate (potassium persulfate); transition metal compounds such as ferric chloride, ferric sulfate, and cupric chloride; metal oxides such as silver oxide and cesium oxide; peroxides such as hydrogen peroxide and ozone; organic peroxides such as benzoyl peroxide; and oxygen.

[0179] The reaction solvent used in the oxidative polymerization can be water or a mixture of water and a solvent. The solvent used here is preferably a solvent that is miscible with water and can dissolve or disperse component (A) and component (B). Examples of suitable solvents include polar solvents such as N-methyl-2-pyrrolidone, N,N'-dimethylformamide, N,N'-dimethylacetamide, dimethyl sulfoxide, and hexamethylene phosphortriamide; alcohols such as methanol, ethanol, propanol, and butanol; polyhydric aliphatic alcohols such as ethylene glycol, propylene glycol, dipropylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, D-glucose, D-glucitol, isoprene glycol, butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,9-nonanediol, and neopentyl glycol; and ethylene glycol. Examples of suitable solvents include carbonate compounds such as carbonate and propylene carbonate, cyclic ether compounds such as dioxane and tetrahydrofuran, chain ethers such as dialkyl ethers, ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers, propylene glycol monoalkyl ethers, propylene glycol dialkyl ethers, polyethylene glycol dialkyl ethers, and polypropylene glycol dialkyl ethers, heterocyclic compounds such as 3-methyl-2-oxazolidinone, and nitrile compounds such as acetonitrile, glutaronitrile, methoxyacetonitrile, propionitrile, and benzonitrile. These solvents may be used alone or as a mixture of two or more. The amount of these water-miscible solvents to be used is preferably 50% by mass or less of the total reaction solvent.

[0180] After the conductive polymer composite is synthesized, a neutralization reaction may be carried out to convert it into a sodium salt, potassium salt, ammonium salt, or sulfonium salt.

[0181] The conductive polymer composite thus obtained can be used after being pulverized into fine particles using a homogenizer, a ball mill, or the like, if necessary. For the particle size reduction, it is preferable to use a mixer / disperser capable of applying high shear force, such as a homogenizer, a high-pressure homogenizer, or a bead mill, with a high-pressure homogenizer being preferred.

[0182] Specific examples of high-pressure homogenizers include Nanovaita manufactured by Yoshida Kikai Kogyo Co., Ltd., Microfluidizer manufactured by Powrex Corporation, and Ultimizer manufactured by Sugino Machine Co., Ltd. Examples of dispersion treatments using a high-pressure homogenizer include a treatment in which the complex solution before dispersion treatment is subjected to opposing collision at high pressure, and a treatment in which the complex solution is passed through an orifice or slit at high pressure.

[0183] Before or after pulverization, impurities may be removed by techniques such as filtration, ultrafiltration, and dialysis, and the product may be purified with a cation exchange resin, anion exchange resin, chelating resin, or the like.

[0184] The total content of components (A) and (B) in the conductive polymer composite solution is preferably 0.05 to 5.0% by mass. If the total content of components (A) and (B) is 0.05% by mass or more, sufficient conductivity is obtained, and if it is 5.0% by mass or less, a uniform conductive coating film can be easily obtained.

[0185] The content of component (B) is preferably an amount such that the number of sulfo groups, sulfonamide groups, and sulfonimide groups in component (B) is in the range of 0.1 to 10 moles per mole of component (A), and more preferably in the range of 1 to 7 moles. If the number of sulfo groups in component (B) is 0.1 moles or more, the doping effect on component (A) is high, and sufficient conductivity can be ensured. Furthermore, if the number of sulfo groups in component (B) is 10 moles or less, the content of component (A) is also appropriate, and sufficient conductivity can be obtained.

[0186] Examples of organic solvents that can be added to the aqueous polymerization reaction solution or that can be used to dilute the monomers include methanol, ethyl acetate, cyclohexanone, methyl amyl ketone, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, t-butyl propionate, propylene glycol mono t-butyl ether acetate, γ-butyrolactone, and mixtures thereof.

[0187] The amount of organic solvent used is preferably 0 to 1,000 mL, particularly preferably 0 to 500 mL, per mole of monomer. If the amount of organic solvent is 1,000 mL or less, the reaction vessel will not become too large, which is economical.

[0188] After polymerizing (A) in the presence of the dopant polymer (B) to form a composite, a neutralizing agent can be added to form a sodium salt, potassium salt, ammonium salt, or sulfonium salt.

[0189] [Other ingredients] (surfactant) In the present invention, a surfactant may be added to improve the wettability of the conductive polymer composite solution to a workpiece such as a substrate. Examples of such surfactants include nonionic, cationic, and anionic surfactants. Specific examples include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene carboxylic acid esters, sorbitan esters, and polyoxyethylene sorbitan esters; cationic surfactants such as alkyltrimethylammonium chloride and alkylbenzylammonium chloride; anionic surfactants such as alkyl or alkylaryl sulfates, alkyl or alkylaryl sulfonates, and dialkyl sulfosuccinates; and zwitterionic surfactants such as amino acid and betaine surfactants. The amount of surfactant added is preferably in the range of 0.01 to 100 parts by mass per 100 parts by mass of the conductive polymer composite.

[0190] (High conductivity agent) In the present invention, an organic solvent may be added as a conductivity-enhancing agent in addition to the main solvent in order to improve the conductivity of the conductive polymer composite. Examples of such conductivity-enhancing agents include polar solvents, such as ethylene glycol, diethylene glycol, polyethylene glycol, glycerin, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP), sulfolane, and mixtures thereof. The amount of the agent added is preferably 1.0 to 40.0% by mass, and more preferably 3.0 to 30.0% by mass, based on the main solvent.

[0191] The conductive polymer composite as described above has good filterability and film-forming properties by spin coating, and can form a conductive polymer composite layer with high transparency and low surface roughness.

[0192] The conductive polymer composite (solution) obtained as described above can be applied to the conductive layer (C) on the substrate (D) to form a bioelectrode. The conductive layer preferably contains one or more metals selected from gold, silver, silver chloride, platinum, aluminum, magnesium, tin, tungsten, iron, copper, nickel, stainless steel, chromium, titanium, and carbon. Examples of methods for applying the conductive polymer composite (solution) include application using a spin coater, bar coater, immersion, comma coating, spray coating, roll coating, screen printing, flexographic printing, gravure printing, and inkjet printing. After application, a bioelectrode can be formed by heat treatment using a hot air circulating oven, a hot plate, or the like.

[0193] [(E) Resin] The (E) resin blended into the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention is a component that is compatible with the (B) dopant polymer (salt) described above, prevents elution of the composite, and retains the conductivity enhancer, such as metal powder, carbon material, silicon powder, or lithium titanate powder, as described below. The (E) resin is preferably one or more resins selected from (meth)acrylate resins, (meth)acrylamide resins, urethane resins, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline, polyglycerin, polyglycerin-modified silicone, cellulose, polyethylene glycol, and polypropylene glycol. The amount of (E) resin added is preferably in the range of 1 to 100 parts by mass per 100 parts by mass of the conductive polymer composite.

[0194] [Component (F)] The conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention can further contain, as component (F), one or more selected from carbon materials, metal powders, silicon powders, and lithium titanate powders. Of component (F), the carbon materials and metal powders are added to enhance electronic conductivity, while the silicon powders and lithium titanate powders are added to enhance ion acceptance sensitivity. The amount added is preferably in the range of 5 to 30 parts by mass per 100 parts by mass of the conductive polymer composite.

[0195] [Metal powder] To enhance electronic conductivity, a metal powder selected from gold, silver, platinum, copper, tin, titanium, nickel, aluminum, tungsten, molybdenum, ruthenium, chromium, and indium may be added to the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention. The amount of metal powder added is preferably in the range of 1 to 50 parts by mass per 100 parts by mass of the conductive polymer composite.

[0196] As the type of metal powder, gold, silver, and platinum are preferred from the viewpoint of conductivity, and silver, copper, tin, titanium, nickel, aluminum, tungsten, molybdenum, ruthenium, and chromium are preferred from the viewpoint of cost. From the viewpoint of biocompatibility, noble metals are preferred, and from these viewpoints overall, silver is most preferred.

[0197] Metal powders can be spherical, discoid, flake, or needle-shaped, but adding flake or needle-shaped powders is the most preferable because it provides the highest conductivity. In the case of flake-shaped powders, the size of the metal powder must be 100 μm or less and the tap density must be 5 g / cm. 3 The specific surface area is 0.5m 2 Flakes with a relatively low density of 1 / g or more and a large specific surface area are preferred. If they are needle-shaped, they preferably have a diameter of 1 to 200 nm and a length of 1 to 500 μm.

[0198] [Carbon materials] A carbon material can be added as a conductivity improver. Examples of the carbon material include carbon black, graphite, carbon nanotubes, and carbon fibers. The carbon nanotubes may be single-walled or multi-walled, and the surface may be modified with an organic group. In particular, either or both of carbon black and carbon nanotubes are preferred. The amount of the carbon material added is preferably in the range of 1 to 50 parts by mass per 100 parts by mass of the conductive polymer composite.

[0199] [Silicon powder] Silicon powder can be added to the conductive polymer composite used to form the conductive polymer composite layer used in the bioelectrode of the present invention to enhance ion reception sensitivity. Examples of silicon powder include powders made of silicon, silicon monoxide, or silicon carbide. The particle size of the powder is preferably smaller than 100 μm, more preferably 1 μm or less. Finer particles have a larger surface area and can therefore receive more ions, resulting in a highly sensitive bioelectrode. The amount of silicon powder added is preferably in the range of 1 to 50 parts by mass per 100 parts by mass of the conductive polymer composite.

[0200] [Lithium titanate powder] To enhance the sensitivity of ion reception, lithium titanate powder can be added to the conductive polymer composite used to form the conductive polymer composite layer of the bioelectrode of the present invention. Examples of lithium titanate powder include Li2TiO3, LiTiO2, and spinel-structured Li4Ti5O. 12 The molecular formula is as follows, and spinel structure products are preferred. Lithium titanate particles composited with carbon can also be used. The particle size of the powder is preferably smaller than 100 μm, more preferably 1 μm or less. Finer particles have a larger surface area and can therefore receive more ions, resulting in a highly sensitive bioelectrode. These may also be composite powders with carbon. The amount of lithium titanate powder added is preferably in the range of 1 to 50 parts by mass per 100 parts by mass of the conductive polymer composite.

[0201] When needle-shaped or fibrous conductive additives such as silver nanowires or carbon nanotubes are added to the conductive polymer composite solution, sufficient conductivity as a bioelectrode can be ensured without providing a conductive layer underneath.

[0202] [Optional ingredients] The conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention may contain optional components such as an ionic additive, a silicone compound having a polyglycerin structure, and an organic solvent.

[0203] [Ionic additives] The conductive polymer composite used to form the conductive polymer composite layer used in the bioelectrode of the present invention can be added with an ionic additive to increase ionic conductivity. In consideration of biocompatibility, examples of such additives include sodium chloride, potassium chloride, calcium chloride, saccharin, acesulfame potassium, and the salts disclosed in JP 2018-044147, JP 2018-059050, JP 2018-059052, and JP 2018-130534.

[0204] Ammonium salts of sulfonic acid, fluorosulfonic acid, fluoroimidic acid, and fluoromethic acid are known as ionic liquids. Specifically, these ionic liquids described in Trulove C, Mantz R. 2003. Ionic Liquids in Synthesis, Chapter 3.6: Electrochemical Properties of Ionic Liquids. The amount of ionic additive added is preferably 1 to 50 parts by mass, and more preferably 2 to 30 parts by mass, per 100 parts by mass of the total of components (A) and (B).

[0205] [Silicone compounds with polyglycerin structure] A silicone compound having a polyglycerin structure can be added to the conductive polymer composite used to form the conductive polymer composite layer used in the bioelectrode of the present invention in order to improve the moisture retention of the conductive polymer composite layer and thereby improve the sensitivity and ionic conductivity of ions released from the skin. The amount of the silicone compound having a polyglycerin structure is preferably 0.01 to 100 parts by mass, more preferably 0.5 to 60 parts by mass, per 100 parts by mass of the total of components (A) and (B). Furthermore, the silicone compound having a polyglycerin structure may be used alone or in combination of two or more types.

[0206] The silicone compound having a polyglycerin structure is preferably one represented by the following general formula (4)' or (5)'. [ka] (In general formulas (4)' and (5)', R 1 are each independent and may be the same or different, and each represent a hydrogen atom, a linear or branched alkyl group having 1 to 50 carbon atoms, or a phenyl group, and may contain an ether group or may be a silicone chain represented by general formula (6)'; R 2 R' is a group having a polyglycerin structure represented by formula (4)'-1 or formula (4)'-2, 3 ' are each independent and may be the same or different, and 1 ' or the R 2 ' and R 4 ' are each independent and may be the same or different, and 1 ', said R 2 ' or an oxygen atom. R 4 If ' is an oxygen atom, R 4 a' may be bonded to each other to form a single ether group and form a ring together with the silicon atom. a' may be the same or different and is 0 to 100, b' is 0 to 100, and a' + b' is 0 to 200. However, when b' is 0, R 3 At least one of the R 2 In general formulas (4)'-1 and (4)'-2, R 5 ' is an alkylene group having 2 to 10 carbon atoms or an aralkylene group having 7 to 10 carbon atoms, and R 6 ', R 7 ', and R 8 ' is an alkylene group having 2 to 6 carbon atoms, and R 7 c' may be an ether bond, c' is 0 to 20, and d' is 1 to 20.

[0207] Examples of such silicone compounds having a polyglycerin structure include the following:

[0208] [ka]

[0209] [ka]

[0210] [ka]

[0211] [ka]

[0212] [ka]

[0213] [ka]

[0214] [ka]

[0215] [ka]

[0216] [ka]

[0217] [ka] (wherein a', b', c' and d' are as defined above)

[0218] A conductive polymer composite containing a silicone compound having such a polyglycerin structure can exhibit better moisturizing properties, and as a result, can form a conductive polymer composite layer that can exhibit better sensitivity to ions released from the skin.

[0219] [Organic solvents] In addition, an organic solvent can be added to the conductive polymer composite for forming the conductive polymer composite layer used in the bioelectrode of the present invention. Specific examples of the organic solvent include water, heavy water, and alcohols such as methanol, ethanol, propanol, and butanol. ,workmanPolyhydric aliphatic alcohols such as ethylene glycol, propylene glycol, 1,3-propanediol, dipropylene glycol, 1,3-butylene glycol, 1,4-butylene glycol, D-glucose, D-glucitol, isoprene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,9-nonanediol, and neopentyl glycol; chain ethers such as dialkyl ethers, ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers, propylene glycol monoalkyl ethers, propylene glycol dialkyl ethers, polyethylene glycol dialkyl ethers, and polypropylene glycol dialkyl ethers; cyclic ether compounds such as dioxane and tetrahydrofuran; cyclohexanone, methyl amyl ketone, ethyl acetate, butanediol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol Examples of the polar solvent include diol monomethyl ether, butanediol monoethyl ether, propylene glycol monoethyl ether, ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, t-butyl propionate, propylene glycol mono t-butyl ether acetate, γ-butyrolactone, N-methyl-2-pyrrolidone, N,N′-dimethylformamide, N,N′-dimethylacetamide, dimethyl sulfoxide, and hexamethylene phosphortriamide; carbonate compounds such as ethylene carbonate and propylene carbonate; heterocyclic compounds such as 3-methyl-2-oxazolidinone; nitrile compounds such as acetonitrile, glutaronitrile, methoxyacetonitrile, propionitrile, and benzonitrile; and mixtures thereof.

[0220] The amount of organic solvent added is preferably within a range from 10 to 50,000 parts by mass per 100 parts by mass of the total of components (A) and (B).

[0221] The bioelectrode of the present invention will be described in detail below with reference to the drawings, but the present invention is not limited thereto.

[0222] 1 is a cross-sectional view of a conductive layer 1-1 formed on a YR-colored substrate 1. In this case, the conductive layer 1-1 is made of metal nanowires.

[0223] 2 is a cross-sectional view of a bioelectrode 2 of the present invention in which a conductive polymer composite layer 1-2 is formed on a conductive layer 1-1 on a YR-colored substrate 1. The conductive polymer composite layer 1-2 may cover the entire conductive layer 1-1, or may be partially exposed on the surface.

[0224] The YR color substrate 1 may be a single layer as shown in FIG. 2, or may be a laminate of a transparent substrate 3 and a YR color film 4 as shown in FIGS.

[0225] 5 is a cross-sectional view of a bioelectrode 2 of the present invention attached to the skin 6. One side of the conductive polymer composite layer 1-2 is in contact with the skin 6, and the other side is in contact with the conductive layer 1-1.

[0226] 6 is a cross-sectional view of the substrate 1 having an anti-reflection mechanism 7. In this case, the anti-reflection mechanism 7 may have YR colors.

[0227] Cross-sectional views of substrates having moth-eye antireflection mechanisms are shown in Figures 7 to 9. The moth-eye structure is a structure in which the substrate surface is thick and becomes thinner towards the upper surface, and the cross section can be any shape, such as triangular, trapezoidal, or cylindrical.

[0228] As shown in Fig. 10, not only the substrate but also the moth-eye type anti-reflection mechanism may have YR colors. Alternatively, as shown in Fig. 11, the substrate may be transparent and the moth-eye type anti-reflection mechanism may have YR colors.

[0229] 12 and 13 are plan views of the moth-eye anti-reflection mechanism as viewed from above. The shape as viewed from above may be any shape, such as a circle, polygon, square, triangle, or irregular shape, and the shape, pattern pitch, and height may be uniform or irregular.

[0230] A top view of straight conductive wiring less than 200 μm wide formed by printing is shown in Figure 14. The gaps between the wiring improve transparency, and providing multiple wiring improves conductivity.

[0231] A top view of zigzag conductive wiring with a width of 200 μm or less formed by printing is shown in Figure 15. When stretched left and right, the zigzag wiring pattern shows less change in conductivity when stretched.

[0232] Figure 16 shows a top view of a zigzag (wavy line) conductive wiring pattern with rounded corners less than 200 μm wide formed by printing. This pattern shows less change in conductivity when stretched than a zigzag wiring pattern with straight lines and acute angles.

[0233] Figure 17 shows a top view of conductive wiring formed by printing, which is less than 200 μm wide and combines two zigzags. This pattern shows less change in conductivity when stretched than the zigzag wiring pattern shown in Figure 15, which consists of a straight line and a single acute angle.

[0234] The zigzag pattern of conductive wiring may be not only horizontal zigzags as shown in Figures 15 to 17, but also vertical to the substrate as shown in JP 2020-107875 A.

[0235] The printed pattern of the conductive wiring may be an independent one as shown in Figures 15 to 17, or may include wiring to connect upper and lower wirings. Examples include a lattice pattern (sash pattern) shown in Figure 18, a tortoiseshell pattern shown in Figure 19, a pattern of connected circles shown in Figures 20 and 21, and a mesh pattern shown in Figure 22. Other examples include the Hinoki fence pattern, which is made up of repeated diagonally arranged rectangles, the Mutsude Manji pattern, which is made up of a combination of hexagons, the Kagome pattern, which is made up of a combination of equilateral triangles and straight lines, the Bishamon Kikko pattern, the Fundo Tsunagi pattern, which is made up of diagonally crossed curves, the Tokkuri Ajiro pattern, and the Hoshi Shippo pattern, which is made up of overlapping circles (see http: / / www.natubunko.net / wagara / kotoba09g.htm, http: / / www.natubunko.net / wagara / kotoba09f.htm).

[0236] Figure 23 shows a top view of a conductive layer formed by applying a solution containing metal nanowires. The gaps between the metal nanowires improve transparency. The contact between the metal nanowires ensures conductivity during expansion and contraction.

[0237] The moth-eye anti-reflection mechanism can be attached not only to the front side of the substrate but also to the back side. Figure 24 shows a case where a substrate 1 is applied with a moth-eye anti-reflection mechanism 8 also attached to the conductive layer 1-1 on the back side. When conductive wiring is formed on a moth-eye substrate with unevenness, a zigzag pattern is formed in the vertical direction, as shown in JP 2020-107875 A, which has the advantage of excellent stretchability.

[0238] Each of the constituent materials of the bioelectrode of the present invention will be described in more detail below.

[0239] [Adhesive layer] The bioelectrode of the present invention has a conductive polymer composite layer formed on a conductive layer on a substrate. This conductive polymer composite layer is the part that actually comes into contact with the living body when the bioelectrode is used. To increase adhesive strength, an adhesive layer can be provided around the conductive polymer composite layer.

[0240] The adhesive strength of the adhesive layer is preferably in the range of 0.5 N / 25 mm or more and 20 N / 25 mm or less. The adhesive strength is generally measured by the method specified in JIS Z 0237. While metal substrates such as SUS (stainless steel) and PET (polyethylene terephthalate) substrates can be used as substrates, measurements can also be made using human skin. The surface energy of human skin is lower than that of metals and various plastics, and is close to that of Teflon (registered trademark), making it less adhesive.

[0241] The thickness of the bioelectrode is preferably 1 nm or more and 1 mm or less, and more preferably 2 nm or more and 0.5 mm or less.

[0242] <Method of manufacturing bioelectrodes> The present invention also provides a method for producing a bioelectrode, which includes preparing a conductive layer on a substrate and then forming a conductive polymer composite layer on the side of the conductive layer that is to be attached to the skin. That is, the method for producing a bioelectrode includes applying a solution containing metal nanowires or printing a conductive paste containing conductive particles onto the (D) substrate, which has a transmittance of 20% or more at a wavelength of 600 nm and a yellow-red (YR) color in the Munsell color system, with a lightness of 1 to 9 and a saturation of 1 to 12, to form the (C) conductive layer, and then applying the conductive polymer composite thereon to form the conductive polymer composite layer, thereby forming the bioelectrode described above.

[0243] When forming the conductive layer (C) on the substrate (D), examples of the method include printing a conductive paste containing conductive particles and applying an ink (solution) containing metal nanowires.

[0244] (C) When a conductive polymer composite layer is formed on a conductive layer, a method of applying a conductive polymer composite can be used.

[0245] The method for applying the conductive polymer complex onto the (C) conductive layer is not particularly limited, and includes a direct application method and a method in which the conductive polymer complex is applied onto another substrate and then transferred. In either case, methods such as dip coating, spray coating, spin coating, roll coating, flow coating, doctor coating, screen printing, flexographic printing, gravure printing, and inkjet printing are suitable.

[0246] A method of printing a conductive paste containing conductive particles or a method of applying ink containing metal nanowires can also be used in the same manner as the method of applying a conductive polymer composite.

[0247] After coating the conductive paste or ink containing metal nanowires, or after coating the conductive polymer composite, heating is performed to evaporate the solvent and solidify the film.

[0248] The temperature at which the conductive polymer composite is heated after coating is not particularly limited and may be selected appropriately depending on the types of components (A) and (B) used in the conductive polymer composite, but a temperature of, for example, about 50 to 250°C is preferred.

[0249] When silver nanowires or the like are used as the conductive film, the heating temperature after coating with conductive paste or ink containing metal nanowires is 70 to 600°C to fuse the silver together. At this time, to prevent thermal decomposition of the substrate, a flash annealing method can be used, in which high-intensity ultraviolet light is irradiated for a short period of time.

[0250] When heating and light irradiation are combined, heating and light irradiation may be performed simultaneously, or heating may be performed after light irradiation, or light irradiation may be performed after heating. Furthermore, air drying may be performed after coating and before heating in order to evaporate the solvent.

[0251] After curing, applying water droplets or spraying water vapor or mist on the surface of the conductive polymer composite layer improves its compatibility with the skin, allowing for quick acquisition of biosignals. Water mixed with alcohol can also be used to reduce the size of the vapor or mist droplets. The surface of the conductive polymer composite layer can also be wetted by contacting it with absorbent cotton or cloth soaked in water.

[0252] The water that wets the surface of the cured conductive polymer composite layer may contain a salt, and the water-soluble salt that is mixed with water is preferably selected from sodium salts, potassium salts, calcium salts, magnesium salts, and betaine.

[0253] Specifically, the water-soluble salt may be a salt selected from sodium chloride, potassium chloride, calcium chloride, magnesium chloride, saccharin sodium salt, acesulfame potassium, sodium carboxylate, potassium carboxylate, calcium carboxylate, sodium sulfonate, potassium sulfonate, calcium sulfonate, sodium phosphate, potassium phosphate, calcium phosphate, magnesium phosphate, and betaine. Note that the above-mentioned (B) dopant polymer is not included in the water-soluble salt.

[0254] More specifically, in addition to the above, sodium acetate, sodium propionate, sodium pivalate, sodium glycolate, sodium butyrate, sodium valerate, sodium caproate, sodium enanthate, sodium caprylate, sodium pelargonate, sodium caprate, sodium undecylate, sodium laurate, sodium tridecylate, sodium myristate, sodium pentadecylate, sodium palmitate, sodium margarate, sodium stearate, sodium benzoate, disodium adipate, disodium maleate, and disodium phthalate 、2 Sodium -hydroxybutyrate, Sodium 3-hydroxybutyrate, Sodium 2-oxobutyrate , GuSodium luconate, sodium methanesulfonate, sodium 1-nonanesulfonate, sodium 1-decanesulfonate, sodium 1-dodecanesulfonate, sodium 1-undecanesulfonate, cocoyl stomach Sodium ethionate, sodium lauroyl methyl alanine, sodium methyl cocoyl taurate, sodium cocoyl glutamate, sodium cocoyl sarcosine, sodium lauroyl methyl taurate, laumidopropyl Betaine Examples include potassium isobutyrate, potassium propionate, potassium pivalate, potassium glycolate, potassium gluconate, potassium methanesulfonate, calcium stearate, calcium glycolate, calcium gluconate, calcium 3-methyl-2-oxobutyrate, and calcium methanesulfonate. Betaine is a general term for an intramolecular salt, specifically a compound in which three methyl groups are added to the amino group of an amino acid, but more specific examples include trimethylglycine, carnitine, and proline betaine.

[0255] The water-soluble salt may further contain a monohydric alcohol or polyhydric alcohol having 1 to 4 carbon atoms, and the alcohol is preferably selected from ethanol, isopropyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, glycerin, polyethylene glycol, polypropylene glycol, polyglycerin, diglycerin, or a silicone compound having a polyglycerin structure, and more preferably the silicone compound having a polyglycerin structure is represented by the above general formula (4)'.

[0256] Pretreatment with a salt-containing aqueous solution can be performed by wetting the cured conductive polymer composite layer (bioelectrode membrane) using methods such as spraying or dispensing water droplets. Wetting can also be performed in high-temperature, high-humidity conditions, such as in a sauna. After wetting, the electrode can be covered with a sheet to prevent drying. Because the sheet must be removed immediately before application to the skin, it is coated with a release agent or uses a release-resistant fluororesin film. For long-term storage, dry electrodes covered with a release sheet are sealed in a bag covered with aluminum or other material. To prevent drying inside the aluminum-covered bag, it is preferable to seal moisture within the bag.

[0257] Wiping or spraying the skin on the side where the bioelectrode will be attached with a cloth containing water or a water-containing alcohol such as ethanol or glycerin immediately before attachment is effective in moistening the skin surface and obtaining highly sensitive and accurate biosignals in a shorter time. Wiping with a water-containing cloth not only moistens the skin but also removes oils and grease from the skin surface, thereby improving the sensitivity of the biosignal.

[0258] As described above, the manufacturing method of the bioelectrode of the present invention allows for the production of a thin, highly transparent bioelectrode that is only slightly different in color from the skin, has high sensitivity to biosignals, is highly biocompatible, is lightweight, and is low-cost.The bioelectrode of the present invention does not lose its sensitivity to biosignals significantly even when wet or dry, or when attached to the skin for a long period of time, and is comfortable to the touch and does not cause itching, redness, or rashes on the skin.This method makes it possible to easily manufacture the bioelectrode of the present invention at low cost. [Example]

[0259] The present invention will be described in detail below using examples and comparative examples, but the present invention is not limited to these. The molecular weight (Mw) and dispersity (Mw / Mn) of the obtained polymer were confirmed by gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent.

[0260] (Synthesis of dopant polymer 1) Under a nitrogen atmosphere, a solution of 54.5 g of Monomer 1 and 4.19 g of dimethyl 2,2'-azobis(isobutyrate) in 112.5 g of methanol was added dropwise over 4 hours to 37.5 g of methanol stirred at 64°C. The mixture was further stirred at 64°C for 4 hours. After cooling to room temperature, the mixture was added dropwise to 1,000 g of ethyl acetate with vigorous stirring. The resulting solid was filtered and dried in vacuum at 50°C for 15 hours to obtain 43.6 g of a white polymer. The resulting white polymer was dissolved in 396 g of methanol, and the ammonium salt was converted to a sulfo group using an ion exchange resin. 19 F, 1 H-NMR and GPC measurements gave the following analytical results. Weight average molecular weight (Mw)=12,400 Molecular weight distribution (Mw / Mn)=1.51 This polymer compound is referred to as dopant polymer 1. [ka]

[0261] Dopant Polymer 1 [ka]

[0262] In the same manner, the following dopant polymers 2 to 25 were polymerized.

[0263] Dopant Polymer 2 Mw=14,000 Mw / Mn=1.41 [ka]

[0264] Dopant Polymer 3 Mw=10,300 Mw / Mn=1.48 [ka]

[0265] Dopant Polymer 4 Mw=12,500 Mw / Mn=1.53 [ka]

[0266] Dopant Polymer 5 Mw=8,500 Mw / Mn=1.67 [ka]

[0267] Dopant Polymer 6 Mw=12,500 Mw / Mn=1.68 [ka]

[0268] Dopant Polymer 7 Mw=15,500 Mw / Mn=1.78 [ka]

[0269] Dopant Polymer 8 Mw=13,500 Mw / Mn=1.69 [ka]

[0270] Dopant Polymer 9 Mw=10,500 Mw / Mn=1.69 [ka]

[0271] Dopant Polymer 10 Mw=8,500 Mw / Mn=1.59 [ka]

[0272] Dopant Polymer 11 Mw=11.00 0 Mw / Mn=1.73 [ka]

[0273] Dopant Polymer 12 Mw=17,100 Mw / Mn=1.73 [ka]

[0274] Dopant Polymer 13 Mw=15,400 Mw / Mn=1.74 [ka]

[0275] Dopant Polymer 14 Mw=16,800 Mw / Mn=1.83 [ka]

[0276] Dopant Polymer 15 Mw=12,900 Mw / Mn=1.74 [ka]

[0277] Dopant Polymer 16 Mw=10,400 Mw / Mn=1.73 [ka]

[0278] Dopant Polymer 17 Mw=16,500 Mw / Mn=1.79 [ka]

[0279] Dopant Polymer 18 Mw=15,700 Mw / Mn=1.81 [ka]

[0280] Dopant Polymer 19 Mw=16,100 Mw / Mn=1.84 [ka]

[0281] Dopant Polymer 20 Mw=11,400 Mw / Mn=1.65 [ka]

[0282] Dopant Polymer 21 Mw=14,400 Mw / Mn=1.78 [ka]

[0283] Dopant Polymer 22 Mw=17,400 Mw / Mn=1.88 [ka]

[0284] Dopant Polymer 23 Mw=11,300 Mw / Mn=1.59 [ka]

[0285] Dopant Polymer 24 Mw=12,100 Mw / Mn=1.56 [ka]

[0286] Dopant Polymer 25 Mw=12,900 Mw / Mn=1.69 [ka]

[0287] [Preparation of Conductive Polymer Composite Solutions Containing Polythiophene as a π-Conjugated Polymer] (Preparation Example 1) 3.82 g of 3,4-ethylenedioxythiophene and a solution prepared by dissolving 15.0 g of dopant polymer 1 in 1,000 mL of ultrapure water were mixed at 30°C. The resulting mixed solution was kept at 30°C and, while stirring, an oxidation catalyst solution of 8.40 g of sodium persulfate and 2.3 g of ferric sulfate dissolved in 100 mL of ultrapure water was slowly added, and the mixture was allowed to react with stirring for 4 hours. 1,000 mL of ultrapure water was added to the resulting reaction solution, and approximately 1,000 mL of the solution was removed using ultrafiltration. This procedure was repeated three times. Then, 200 mL of sulfuric acid diluted to 10% by mass and 2,000 mL of ion-exchanged water were added to the filtered solution, and approximately 2,000 mL of the treated solution was removed using ultrafiltration. 2,000 mL of ion-exchanged water was added to this, and approximately 2,000 mL of the solution was removed using ultrafiltration. This procedure was repeated three times. The resulting treated solution was purified using a cation exchange resin and an anion exchange resin, after which 2,000 mL of ion-exchanged water was added, and approximately 2,000 mL of the treated solution was removed using ultrafiltration. This procedure was repeated five times to obtain a 1.0 mass% conductive polymer composite solution 1.

[0288] The ultrafiltration conditions were as follows: Ultrafiltration membrane molecular weight cutoff: 30K Cross-flow type Feed liquid flow rate: 3,000mL / min Transmembrane partial pressure: 0.12 Pa In other preparation examples, ultrafiltration was carried out under similar conditions.

[0289] (Preparation Example 2) 3.07 g of 3-methoxythiophene and a solution prepared by dissolving 15.0 g of dopant polymer 1 in 1,000 mL of pure water were mixed at 30°C. The resulting mixed solution was kept at 30°C and, while stirring, an oxidation catalyst solution of 8.40 g of sodium persulfate and 2.3 g of ferric sulfate dissolved in 100 mL of ultrapure water was slowly added, and the mixture was allowed to react with stirring for 4 hours. 1,000 mL of ultrapure water was added to the resulting reaction solution, and approximately 1,000 mL of the solution was removed using ultrafiltration. This procedure was repeated three times. Then, 200 mL of sulfuric acid diluted to 10% by mass and 2,000 mL of ion-exchanged water were added to the filtered solution, and approximately 2,000 mL of the treated solution was removed using ultrafiltration. 2,000 mL of ion-exchanged water was added to this, and approximately 2,000 mL of the solution was removed using ultrafiltration. This procedure was repeated three times. The resulting treated solution was purified using a cation exchange resin and an anion exchange resin, after which 2,000 mL of ion-exchanged water was added, and approximately 2,000 mL of the treated solution was removed using ultrafiltration. This procedure was repeated five times to obtain a 1.0 mass% conductive polymer composite solution 2.

[0290] (Preparation Examples 3 to 26) Dopant polymer 1 in Preparation Example 1 was changed to dopant polymers 2 to 25, and 1.0 mass % conductive polymer composite solutions 3 to 26 were obtained.

[0291] (Measurement of the thickness of the biological contact layer) The conductive polymer composite solutions 1 to 26 were spin-coated onto a Si substrate, baked on a hot plate at 120°C for 10 minutes, and the film thickness was measured using an optical film thickness meter. The results are shown in Tables 1 and 2.

[0292] (Preparation of bioelectrodes) A 50 μm-thick transparent thermoplastic urethane (TPU) film was coated by screen printing with Fujikura Kasei's conductive paste, Dotite FA-333, and baked in an oven at 120°C for 10 minutes to print the conductive pattern shown in Figure 14. The conductive pattern had a width of 50 μm, a pitch of 200 μm, 100 lines, and a length of 40 mm. A 30 μm-thick cellophane film with Munsell values ​​of 7YR lightness 8.5 / chroma 3 and a transmittance of 80% at a wavelength of 600 nm was attached to the side opposite the printed surface, forming conductive substrate V, a composite film of a conductive layer and substrate. As shown in Figure 25, a fluororesin adhesive masking tape 9 was applied to half of the square area of ​​the conductive pattern with an area of ​​40 mm x 20 mm on the printed surface, and the conductive polymer composite solution was spin-coated on top of it and baked at 120°C for 10 minutes using a hot plate.The fluororesin adhesive tape was then peeled off, and the conductive substrate on which the conductive polymer composite layer 10 had been formed was cut out along the printed pattern to a size of 20 mm wide and 40 mm long to produce a bioelectrode.

[0293] A solution of Sigma-Aldrich silver nanowires (60 nm diameter, 40 μm length, 5 mg / mL concentration) diluted 10-fold with pure water was spin-coated onto a transparent 50 μm-thick thermoplastic urethane (TPU) film and baked on a hot plate at 130°C for 10 minutes to fuse the silver nanowires to the TPU film. A 30 μm-thick cellophane film with a Munsell value of 2YR 9.0 / chroma 2 and a transmittance of 84% at 600 nm was attached to the opposite side to form the conductive substrate W. The conductive polymer composite solution was spin-coated onto the silver nanowire layer and baked on a hot plate at 120°C for 10 minutes. A bioelectrode was fabricated by cutting it into a size of 20 mm wide and 40 mm long.

[0294] A solution of Sigma-Aldrich silver nanowires (60 nm diameter, 40 μm length, 5 mg / mL concentration) diluted 10-fold with pure water was spin-coated onto a transparent 50 μm-thick thermoplastic urethane (TPU) film and baked on a hot plate at 130°C for 10 minutes to fuse the silver nanowires to the TPU film. A 30 μm-thick cellophane film with a Munsell value of 5YR, a brightness of 8.5, a chroma of 4, and a transmittance of 80% at 600 nm was attached to the opposite side to form the conductive substrate X. The conductive polymer composite solution was spin-coated onto the silver nanowire layer and baked on a hot plate at 120°C for 10 minutes. A bioelectrode was fabricated by cutting it into a size of 20 mm wide and 40 mm long.

[0295] A solution of Sigma-Aldrich silver nanowires (60 nm diameter, 40 μm length, 5 mg / mL concentration) diluted 10-fold with pure water was spin-coated onto a transparent 50 μm-thick thermoplastic urethane (TPU) film and baked on a hot plate at 130 °C for 10 minutes to fuse the silver nanowires to the TPU film. A 30 μm-thick cellophane film with a Munsell value of 5YR, a brightness of 8.5, a chroma of 4, and a transmittance of 80% at 600 nm was attached to the opposite side. A 20 μm-thick PET film with triangular moth-eye anti-reflection features, 100 nm high and 200 nm pitch, was then attached on top of the cellophane film to form the conductive substrate Y. The conductive polymer composite solution was spin-coated onto the silver nanowire layer and baked on a hot plate at 120 °C for 10 minutes. Bioelectrodes were fabricated by cutting the film into pieces 20 mm wide and 40 mm long.

[0296] A solution of Sigma-Aldrich silver nanowires (60 nm diameter, 40 μm length, 5 mg / mL concentration) diluted 10-fold with pure water was spin-coated onto a transparent 50 μm-thick thermoplastic urethane (TPU) film and baked at 130 °C for 10 minutes on a hot plate to fuse the silver nanowires to the TPU film. A 30 μm-thick, 100 nm-high, 200 nm-pitch triangular moth-eye anti-reflection PET film with a Munsell value of 5YR, a brightness of 8.5, a chroma of 4, and a transmittance of 80% at 600 nm was attached to the opposite side to form the conductive substrate Z. The conductive polymer composite solution was spin-coated onto the silver nanowire layer and baked at 120 °C for 10 minutes on a hot plate. Bioelectrodes were fabricated by cutting the film into pieces 20 mm wide and 40 mm long.

[0297] A solution of Sigma-Aldrich silver nanowires (60 nm diameter, 40 μm length, 5 mg / mL concentration) diluted 10-fold with pure water was spin-coated onto a transparent 50 μm-thick thermoplastic urethane (TPU) film and baked on a hot plate at 130°C for 10 minutes to fuse the silver nanowires to the TPU film, creating a comparative conductive substrate. A conductive polymer composite solution was spin-coated onto the silver nanowire layer and baked on a hot plate at 120°C for 10 minutes. A bioelectrode was fabricated by cutting it into a 20 mm wide, 40 mm long piece.

[0298] (Biological signal measurement) The conductive polymer composite solution, solvent, and additives were mixed according to the compositions shown in Tables 1 and 2, stirred at room temperature for 2 hours, and then filtered through regenerated cellulose with a pore size of 1.0 μm to produce a conductive composite polymer solution, which was then spin-coated onto a conductive substrate.

[0299] Cellophane tape was attached to the back of the bioelectrode so that a 20 mm square of the conductive polymer composite layer of the bioelectrode was attached to the skin. It was attached to the arm position shown in Figure 26, which had been treated with water-moistened absorbent cotton. In the conductive pattern printing, the conductive wiring in the masked area was exposed, and the part of the silver nanowire conductive layer that was not attached to the skin was clamped with a metal clip, and the metal clip was connected to the ECG measurement device with the conductive wiring.

[0300] The ECG measurement device used was a NeXus10 MARKII manufactured by Kissei Comtec Co., Ltd. In Figure 26, 11 is the positive electrode, 12 is the negative electrode, and 13 is the ground. The results are shown in Tables 1 and 2.

[0301] (Transmittance measurement) The bioelectrode was placed on the light-receiving side of the transmittance meter, and the transmittance of the bioelectrode at a wavelength of 600 nm was measured. The results are shown in Tables 1 and 2.

[0302] (Munsell color measurement) The Munsell color system of the bioelectrode was measured using a Konica Minolta CM-600d spectrophotometer and color difference meter. The results are shown in Tables 1 and 2.

[0303] additives [ka]

[0304] Fluoroalkyl nonionic surfactant FS-31 (manufactured by DuPont) Lysine histidine Potassium hydroxide potassium bicarbonate

[0305] Amine 1 [ka]

[0306] Amine 2 [ka]

[0307] Salt compounds 1-5 [ka]

[0308] solvent Dimethyl sulfoxide (DMSO) ethylene glycol glycerin

[0309] [Table 1]

[0310] [Table 2]

[0311] The ECG signal was judged to be good if a PQRST wave was present. The bioelectrode of the example had a light orange color similar to the skin color, while the comparative example had a blue color.

[0312] As shown by the results of Examples 1 to 32, the bioelectrode of the present invention, which uses a (D) substrate having a transmittance of 20% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a brightness in the range of 1 to 9 and a saturation in the range of 1 to 12, is thin and highly transparent, has a slight difference from the color of the skin, has high sensitivity to biosignals, is excellent in biocompatibility, is lightweight, and can be manufactured at low cost.The sensitivity of biosignals does not decrease significantly even when wet or dry, or when attached to the skin for a long period of time, and is a comfortable bioelectrode that does not cause itching, redness, or rashes on the skin.

[0313] On the other hand, as shown by the results of Comparative Example 1, when the above-mentioned (D) base material is not used, the bioelectrode becomes blue, which is significantly different from the skin color.

[0314] The present specification includes the following aspects. [1]: A bioelectrode comprising a conductive polymer composite layer, (C) a conductive layer, and (D) a substrate, wherein the conductive polymer composite layer is (A) a π-conjugated polymer, and (B) a dopant polymer containing a repeating unit a having one or more repeating units selected from sulfonic acid, fluorosulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide, and having a weight-average molecular weight in the range of 1,000 to 500,000; a conductive polymer composite comprising: A bioelectrode characterized in that the (D) substrate has a transmittance of 20% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a brightness in the range of 1 to 9 and a saturation in the range of 1 to 12. [2]: The bioelectrode according to [1] above, characterized in that the (C) conductive layer contains one or more selected from gold, silver, silver chloride, platinum, aluminum, magnesium, tin, tungsten, iron, copper, nickel, stainless steel, chromium, titanium, and carbon. [3]: The bioelectrode according to [1] or [2] above, wherein the repeating unit a has a partial structure represented by the following general formulas (1)-1 to (1)-4. [ka] (In the general formula (1)-1, Rf1 and Rf2 are a hydrogen atom, a fluorine atom, an oxygen atom, a methyl group, or a trifluoromethyl group. When Rf1 and Rf2 are oxygen atoms, Rf1 and Rf2 are one oxygen atom that is bonded to one carbon atom to form a carbonyl group. Rf3 and Rf4 are a hydrogen atom, a fluorine atom, or a trifluoromethyl group. At least one of Rf1 to Rf4 is a fluorine atom or a trifluoromethyl group. In the general formula In (1)-2, Rf5 is a hydrogen atom, a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and m is an integer of 1 to 4. In general formulas (1)-3 and (1)-4, Rf6 and Rf7 are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and have at least one fluorine atom. In general formulas (1)-1 to (1)-4, M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions. [4]: The bioelectrode according to the above [3], wherein the repeating unit a has one or more repeating units selected from the repeating units A1 to A7 represented by the following general formula (2): [ka] (In general formula (2), R 1 , R 3 , R 5 , R 8 , R 10 , R 11 , and R 13 are each independently a hydrogen atom or a methyl group, and R 2 , R 4 , R 6 , R 9 , R 12 , and R14 are each independently a single bond or a linear, branched or cyclic hydrocarbon group having 1 to 13 carbon atoms. The hydrocarbon group may have an ester group, an ether group, or both. R 7 is a linear or branched alkylene group having 1 to 4 carbon atoms, and R 7 One or two of the hydrogen atoms in X1, X2, X3, X4, X6, and X7 may be substituted with a fluorine atom. Each of X1, X2, X3, X4, X6, and X7 independently represents a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, or an amide group, and X5 represents a single bond, an ether group, or an ester group. Y represents an oxygen atom or -NR 19 - group. 19 is a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, or a phenyl group, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, and an amide group. 4 may form a ring together with Rf1' and Rf5'. Rf1' and Rf5' are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms and having at least one fluorine atom. m is an integer of 1 to 4. a1, a2, a3, a4, a5, a6, and a7 are each 0≦a1≦1.0, 0≦a2≦1.0, 0≦a3≦1.0, 0≦a4≦1.0, 0≦a5≦1.0, 0≦a6≦1.0, and 0≦a7≦1.0, and <a1+a2+a3+a4+a5+a6+a7≦1.0である。M + is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions. [5]: The bioelectrode according to the above [4], wherein the repeating unit a contains an ammonium ion represented by the following general formula (3) as the ammonium ion constituting the ammonium salt: [ka] (In general formula (3), R 101d , R 101e , R 101f and R 101gR are each a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 15 carbon atoms, a linear, branched, or cyclic alkenyl or alkynyl group having 2 to 12 carbon atoms, or an aromatic group having 4 to 20 carbon atoms, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, a hydroxy group, a carboxy group, an amino group, a nitro group, a sulfonyl group, a sulfinyl group, a halogen atom, and a sulfur atom. 101d and R 101e , or R 101d , R 101e and R 101f may form a ring together with the nitrogen atom to which they are attached, and when they form a ring, R 101d and R 101e , or R 101d , R 101e and R 101f is an alkylene group having 3 to 10 carbon atoms, or forms a heteroaromatic ring having the nitrogen atom in the ring in general formula (3). [6]: A bioelectrode according to any one of [1] to [5] above, characterized in that the conductive polymer composite contains, in addition to the components (A) and (B), one or more (E) resins selected from (meth)acrylate resins, (meth)acrylamide resins, urethane resins, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline, polyglycerin, polyglycerin-modified silicones, cellulose, polyethylene glycol, and polypropylene glycol. [7]: A bioelectrode according to any one of [1] to [6], characterized in that the (D) substrate has a transmittance of 30% or more at a wavelength of 600 nm, is yellow-red (YR) in the Munsell color system, and has a brightness in the range of 1 to 9 and a saturation in the range of 1 to 12. [8]: A bioelectrode according to any one of [1] to [7], characterized in that the (D) substrate has a film attached to the side of the bioelectrode that comes into contact with the skin and / or the opposite side, the film having a transmittance of 30% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a brightness in the range of 1 to 9 and a saturation in the range of 1 to 12. [9]: The bioelectrode according to any one of [1] to [8], characterized in that the (D) substrate has an anti-reflection mechanism on the surface opposite to the side of the bioelectrode that comes into contact with the skin.

[10] : A method for manufacturing a bioelectrode, comprising: forming the (C) conductive layer by applying a solution containing metal nanowires or printing a conductive paste containing conductive particles onto the (D) substrate, which has a transmittance of 20% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a lightness of 1 to 9 and a saturation of 1 to 12; and then applying the conductive polymer composite thereon to form the conductive polymer composite layer, thereby forming any one of the bioelectrodes [1] to [9].

[0315] The present invention is not limited to the above-described embodiments. The above-described embodiments are merely examples, and anything that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits similar effects is included within the technical scope of the present invention. [Explanation of symbols]

[0316] 1...substrate, 1-1...conductive layer, 1-2...conductive polymer composite layer, 2...bioelectrode, 3...transparent substrate, 4...YR color film, 6...Skin, 7...Anti-reflection mechanism, 8...Anti-reflection mechanism, 9...Fluororesin adhesive masking tape, 10...Conductive polymer composite layer 11...positive electrode, 12...negative electrode, 13...ground.

Claims

1. A bioelectrode comprising a conductive polymer composite layer, (C) a conductive layer, and (D) a substrate, wherein the conductive polymer composite layer comprises: (A) a polythiophene, and (B) a dopant polymer containing a repeating unit a having one or more repeating units selected from sulfonic acid, fluorosulfonic acid, fluorosulfonimide, and N-carbonylfluorosulfonamide, and having a weight average molecular weight in the range of 1,000 to 500,000; a conductive polymer composite comprising: the (D) substrate has a transmittance of 20% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, a brightness in the range of 1 to 9, and a chroma in the range of 1 to 12; The repeating unit a has a partial structure represented by the following general formulas (1)-1 to (1)-4, The bioelectrode is characterized in that it has the (C) conductive layer on the (D) substrate, and the (C) conductive polymer composite layer on the conductive layer. 【Chemistry 1】 (In general formula (1)-1, Rf 1 and Rf 2 are hydrogen atoms, fluorine atoms, oxygen atoms, methyl groups, or trifluoromethyl groups; when Rf 1 and Rf 2 are oxygen atoms, Rf 1 and Rf 2 are one oxygen atom bonding to one carbon atom to form a carbonyl group; Rf 3 and Rf 4 are hydrogen atoms, fluorine atoms, or trifluoromethyl groups; and one or more of Rf 1 to Rf 4 are fluorine atoms or trifluoromethyl groups. In general formula (1)-2, Rf 5 is a hydrogen atom, fluorine atom, trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms; and m is an integer of 1 to 4. In general formula (1)-3 and general formula (1)-4, Rf 6 and Rf 7 are each a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and have at least one fluorine atom. In general formulas (1)-1 to (1)-4, M + is an ion selected from a hydrogen ion, an ammonium ion, a sodium ion, and a potassium ion.

2. The bioelectrode according to claim 1, characterized in that the (C) conductive layer contains one or more selected from gold, silver, silver chloride, platinum, aluminum, magnesium, tin, tungsten, iron, copper, nickel, stainless steel, chromium, titanium, and carbon.

3. The bioelectrode according to claim 1, characterized in that the repeating unit a has one or more repeating units selected from repeating units A1 to A7 represented by the following general formula (2): 【Chemistry 2】 (In general formula (2), R １ , R ３ , R ５ , R ８ , R １０ , R １１ , and R １３ are each independently a hydrogen atom or a methyl group, and R ２ , R ４ , R ６ , R ９ , R １２ , and R １４ are each independently a single bond or a linear, branched or cyclic hydrocarbon group having 1 to 13 carbon atoms. The hydrocarbon group may have an ester group, an ether group, or both. ７ is a linear or branched alkylene group having 1 to 4 carbon atoms, and R ７ One or two of the hydrogen atoms in X may be substituted with a fluorine atom. １ , X ２ , X ３ , X ４ , X ６ , and X ７ are each independently a single bond, a phenylene group, a naphthylene group, an ether group, an ester group, or an amide group, and X ５ is a single bond, an ether group, or an ester group. Y is an oxygen atom or —NR １９ - group. １９ is any one of a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 12 carbon atoms, and a phenyl group, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, and an amide group. ４ Rf may form a ring together with １ ' and Rf ５ Each of M' is a fluorine atom, a trifluoromethyl group, or a linear or branched alkyl group having 1 to 4 carbon atoms, and has at least one fluorine atom. m is an integer from 1 to 4. a1, a2, a3, a4, a5, a6, and a7 satisfy the following conditions: 0≦a1≦1.0, 0≦a2≦1.0, 0≦a3≦1.0, 0≦a4≦1.0, 0≦a5≦1.0, 0≦a6≦1.0, 0≦a7≦1.0, and 0<a1+a2+a3+a4+a5+a6+a7≦1.

0. M ＋ is an ion selected from hydrogen ions, ammonium ions, sodium ions, and potassium ions.

4. 4. The bioelectrode according to claim 3, wherein the repeating unit a contains an ammonium ion represented by the following general formula (3) as an ammonium ion constituting the ammonium salt: 【Transformation 3】 (In general formula (3), R １０１ｄ , R １０１ｅ , R １０１ｆ and R １０１ｇ are each a hydrogen atom, a linear, branched, or cyclic alkyl group having 1 to 15 carbon atoms, a linear, branched, or cyclic alkenyl or alkynyl group having 2 to 12 carbon atoms, or an aromatic group having 4 to 20 carbon atoms, and may have one or more groups selected from an ether group, a carbonyl group, an ester group, a hydroxy group, a carboxy group, an amino group, a nitro group, a sulfonyl group, a sulfinyl group, a halogen atom, and a sulfur atom. １０１ｄ and R １０１ｅ , or R １０１ｄ , R １０１ｅ and R １０１ｆ may form a ring together with the nitrogen atom to which they are attached, and when they form a ring, R １０１ｄ and R １０１ｅ , or R １０１ｄ , R １０１ｅ and R １０１ｆ is an alkylene group having 3 to 10 carbon atoms, or forms a heteroaromatic ring having the nitrogen atom in the ring in general formula (3).

5. The bioelectrode according to claim 1, characterized in that the conductive polymer complex contains, in addition to the components (A) and (B), one or more (E) resins selected from a (meth)acrylate resin, a (meth)acrylamide resin, a urethane resin, polyvinyl alcohol, polyvinylpyrrolidone, polyoxazoline, polyglycerin, polyglycerin-modified silicone, cellulose, polyethylene glycol, and polypropylene glycol.

6. The (D) substrate has a transmittance of 30% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, a brightness of 1 to 9, and a saturation of 1 to 12. The bioelectrode according to claim 1.

7. The bioelectrode according to claim 1, characterized in that the (D) substrate has a film attached to the side of the bioelectrode that comes into contact with the skin and / or the opposite side thereof, the film having a transmittance of 30% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a brightness in the range of 1 to 9 and a saturation in the range of 1 to 12.

8. 2. The bioelectrode according to claim 1, wherein the substrate (D) has an anti-reflection mechanism on the surface opposite to the side of the bioelectrode that comes into contact with the skin.

9. A method for manufacturing a bioelectrode, comprising: applying a solution containing metal nanowires or printing a conductive paste containing conductive particles onto the (D) substrate, which has a transmittance of 20% or more at a wavelength of 600 nm, a yellow-red (YR) color in the Munsell color system, and a lightness of 1 to 9 and a saturation of 1 to 12, to form the (C) conductive layer; and applying the conductive polymer composite thereon to form the conductive polymer composite layer, thereby forming the bioelectrode according to any one of claims 1 to 8.

Images