Electrode

Abstract

An electrode (1) comprises, in order in the thickness direction, a resin film (2), a metal underlayer (3), and a conductive carbon layer (4). The surface of the conductive carbon layer (4) has an arithmetic mean roughness Ra of at most 1.50 nm and a skewness Rsk of at least 0.00.

Description

[Technical field]

[0001] The present invention relates to an electrode. [Background technology]

[0002] An electrode is known that includes a flexible substrate, a metal layer, and a conductive carbon layer in that order in the thickness direction (see, for example, Patent Document 1 below). In the electrode described in Patent Document 1, it is described that the surface roughness of the conductive carbon layer is set to 2.0 nm or less to suppress noise. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-105637 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the electrode described in Patent Document 1 has a drawback in that the signal intensity is easily reduced.

[0005] The present invention provides an electrode that can suppress noise while also suppressing a decrease in signal intensity. [Means for solving the problem]

[0006] The present invention (1) includes an electrode comprising a resin film, a metal underlayer, and a conductive carbon layer in that order in a thickness direction, and the surface of the conductive carbon layer has an arithmetic mean roughness Ra of 1.50 nm or less and a skewness Rsk of 0.00 or more.

[0007] The present invention (2) includes the electrode according to (1), in which the conductive carbon layer contains a metal, and the proportion of the metal in the conductive carbon layer is 5 mass % or more and 50 mass % or less.

[0008] The present invention (3) includes the electrode according to (1) or (2), in which the metal is titanium.

[0009] The present invention (4) includes the electrode according to any one of (1) to (3), which is an electrode for electrochemical measurement. Effect of the Invention

[0010] In the electrode of the present invention, the surface of the conductive carbon layer has an arithmetic mean roughness Ra of 1.50 nm or less and a skewness Rsk of 0.00 or more, so that noise can be suppressed while also suppressing a decrease in signal intensity. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view of one embodiment of an electrode of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] <One embodiment> One embodiment of the electrode of the present invention will be described with reference to FIG.

[0013] As shown in Fig. 1, the electrode 1 has a thickness. The electrode 1 has a film shape (including a sheet shape). The electrode 1 includes a resin film 2, a metal base layer 3, and a conductive carbon layer 4, which are arranged in this order toward one side in the thickness direction. Preferably, the electrode 1 includes only the resin film 2, the metal base layer 3, and the conductive carbon layer 4.

[0014] The resin film 2 has a thickness. The resin film 2 is a base film in the electrode 1. The material of the resin film 2 is a resin. Examples of the resin include polyester resin, olefin resin, acetate resin, polyethersulfone resin, polycarbonate resin, polyamide resin, polyimide resin, polyolefin resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polystyrene resin, polyvinyl alcohol resin, polyarylate resin, and polyphenylene sulfide resin. These can be used alone or in combination. Examples of the resin include a polyester resin. Examples of the polyester resin include polyethylene terephthalate (PET) and polyethylene naphthalate. Examples of the polyester resin include a PET.

[0015] There are no particular limitations on the thickness of the resin film 2. The thickness of the resin film 2 is, for example, 2 μm or more, preferably 20 μm or more, and for example, 1000 μm or less, preferably 500 μm or less.

[0016] The arithmetic mean roughness Ra of one surface in the thickness direction of the resin film 2 is not particularly limited. The arithmetic mean roughness Ra of one surface in the thickness direction of the resin film 2 is, for example, 5 nm or less, preferably 1 nm or less, and for example, 0.1 nm or more, preferably 0.3 nm or more. The arithmetic mean roughness Ra of one surface in the thickness direction of the resin film 2 is measured in accordance with JIS B0601:2013. The arithmetic mean roughness Ra of the following layers is also measured in the same manner as above.

[0017] The skewness Rsk of one surface in the thickness direction of the resin film 2 is not particularly limited. The skewness Rsk of one surface in the thickness direction of the resin film 2 is, for example, -0.3 or more, preferably -0.2 or more, and for example, 1.5 or less, preferably 0.8 or less. The skewness Rsk of one surface in the thickness direction of the resin film 2 is determined as the skewness of a roughness curve according to JIS B0601:2013. The skewness Rsk of the following layers is also measured in the same manner as above.

[0018] The metal base layer 3 is disposed on one surface in the thickness direction of the resin film 2. Specifically, the metal base layer 3 is in contact with the entire one surface in the thickness direction of the resin film 2. The metal base layer 3 has a thickness.

[0019] The material of the metal underlayer 3 is a metal. Examples of the metal include titanium, chromium, tungsten, aluminum, copper, silver, gold, molybdenum, tantalum, palladium, silicon, and alloys thereof. A preferable example of the metal is titanium.

[0020] There is no particular limitation on the thickness of the metal underlayer 3. The thickness of the metal underlayer 3 is, for example, 1 nm or more, preferably 3 nm or more, more preferably 5 nm or more, and for example, 1000 nm or less, preferably 100 nm or less, more preferably 50 nm or less.

[0021] The conductive carbon layer 4 is disposed on one surface in the thickness direction of the metal base layer 3. Specifically, the conductive carbon layer 4 is in contact with the entire one surface in the thickness direction of the metal base layer 3. The conductive carbon layer 4 has a thickness.

[0022] The main material of the conductive carbon layer 4 is carbon. Carbon is, for example, sp 2 Bonds and sp 3 Such carbon has a graphite type structure and a diamond structure.

[0023] The conductive carbon layer 4 may further contain a metal. If the conductive carbon layer 4 further contains a metal, noise can be further suppressed while a decrease in signal intensity can also be further suppressed. The metal in the conductive carbon layer 4 may be the same metal as that in the metal underlayer 3, or may be a metal different from that in the metal underlayer 3. Preferably, the metal in the conductive carbon layer 4 is the same metal as that in the metal underlayer 3.

[0024] Examples of the metal include titanium, chromium, tungsten, aluminum, copper, silver, gold, molybdenum, tantalum, palladium, silicon, and alloys thereof. A preferable example of the metal is titanium. If the metal is titanium, the adhesive strength between the conductive carbon layer 4 and the base metal layer 3 can be further increased.

[0025] The proportion of metal in the conductive carbon layer 4 is, for example, 0.1 mass% or more, preferably 1 mass% or more, more preferably 5 mass% or more, and for example, 50 mass% or less, preferably 35 mass% or less, and further preferably 20 mass% or less. When the proportion of metal in the conductive carbon layer 4 is equal to or more than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, noise can be further suppressed while the decrease in signal intensity can be further suppressed. The presence or absence and proportion of metal in the conductive carbon layer 4 can be determined by fluorescent X-ray measurement.

[0026] The conductive carbon layer 4 may further contain a rare gas. Examples of the rare gas include helium, argon, krypton, xenon, and radon. Examples of methods for analyzing the rare gas in the conductive carbon layer 4 include secondary ion mass spectrometry, laser resonance ionization mass spectrometry, and X-ray fluorescence analysis.

[0027] The surface resistance value of the conductive carbon layer 4 on one surface in the thickness direction is not particularly limited. The surface resistance of the conductive carbon layer 4 on one surface in the thickness direction is, for example, 1.0×10 4 Ω / □ or less, preferably 1.0×10 3 The surface resistance is measured by the four-terminal method in accordance with JIS K 7194.

[0028] The thickness of the conductive carbon layer 4 is not particularly limited. The thickness of the conductive carbon layer 4 is, for example, 1 nm or more, preferably 2 nm or more, more preferably 5 nm or more, and is, for example, 100 nm or less, preferably 70 nm or less, more preferably 50 nm or less. If the thickness of the conductive carbon layer 4 is equal to or less than the above-mentioned upper limit, the arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4, which will be described later, can be easily set within a desired range. If the thickness of the conductive carbon layer 4 is equal to or more than the above-mentioned lower limit, a uniform film can be formed in the in-plane direction. The in-plane direction is a direction perpendicular to the thickness direction. The thickness of the conductive carbon layer 4 is calculated by measuring the X-ray reflectance.

[0029] The arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4 is 1.50 nm or less. In this embodiment, the one surface in the thickness direction of the conductive carbon layer 4 is synonymous with the surface of the conductive carbon layer 4. The arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4 is preferably 1.25 nm or less, more preferably 1.00 nm or less, even more preferably 0.75 nm or less, and particularly preferably 0.70 nm or less. If the arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4 exceeds the above-mentioned upper limit, noise cannot be suppressed. Specifically, when cyclic voltammetry is performed using the electrode 1, the capacitance value becomes excessive. Then, the noise increases. That is, in this embodiment, the arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4 is 1.50 nm or less, so that the noise can be suppressed. For example, in this embodiment, the capacitance value in cyclic voltammetry can be reduced, so that the above-mentioned noise suppression is demonstrated (see the Examples section below). In order to set the arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4 within the above range, for example, the thickness of the conductive carbon layer 4 is adjusted.

[0030] On the other hand, there is no particular limitation on the lower limit of the arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4. The lower limit of the arithmetic mean roughness Ra of one surface in the thickness direction of the conductive carbon layer 4 is, for example, 0.01 nm, or preferably 0.10 nm.

[0031] The distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4 is 0.00 or more. The distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4 is preferably 0.15 or more, more preferably 0.20 or more. If the distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4 does not meet the above-mentioned lower limit, the signal intensity decreases. Specifically, when cyclic voltammetry is performed using the electrode 1, the redox potential difference ΔEp increases. Then, the signal intensity decreases. In other words, in this embodiment, since the distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4 is 0.00 or more, the decrease in the signal intensity can be suppressed. This proves that the above-mentioned suppression of the decrease in the signal intensity is suppressed because the redox potential difference ΔEp (specifically, the ferricyanide activity value) is low in cyclic voltammetry (see the Examples section below). To set the distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4 within the above-mentioned range, for example, the type of sputtering method, the power applied to the target, the pressure during sputtering, and / or the thickness of the conductive carbon layer 4 can be adjusted.

[0032] When the skewness Rsk of one surface in the thickness direction of the conductive carbon layer 4 is 0.00 or more, the skewness Rsk is 0 or a positive number. Then, the convex portions on one surface in the thickness direction of the conductive carbon layer 4 become steep and sparse. That is, the intervals between the convex portions become wider, and the proportion of the space occupied by the concave portions becomes larger. Then, it is presumed that a large amount of the substance to be measured can be accommodated in the concave portions and measured with good sensitivity, and a decrease in signal intensity can be suppressed.

[0033] On the other hand, there is no particular upper limit to the distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4. The upper limit of the distortion Rsk of one surface in the thickness direction of the conductive carbon layer 4 is, for example, 1.50.

[0034] Next, a description will be given of a method for manufacturing the electrode 1. First, a resin film 2 is prepared. Next, a metal base layer 3 and a conductive carbon layer 4 are formed in this order on one side of the resin film 2 in the thickness direction.

[0035] Examples of the method for forming the metal underlayer 3 include a dry method and a wet method. A preferred example is a dry method. Examples of the dry method include a PVD method (physical vapor deposition method) and a CVD method (chemical vapor deposition method). A preferred example is a PVD method. Examples of the PVD method include a sputtering method, a vacuum deposition method, a laser deposition method, and an ion plating method (arc deposition method). A preferred example of the PVD method is a sputtering method. The sputtering method is not particularly limited. Examples of the sputtering method include an unbalanced magnetron sputtering method (UBM sputtering method), a high-power pulse sputtering method, an electron cyclotron resonance sputtering method, an RF sputtering method, a DC sputtering method (DC magnetron sputtering method), a DC pulse sputtering method, and an ion beam sputtering method.

[0036] In the sputtering method, for example, a sputtering gas and a target are used. The sputtering gas includes a rare gas. Examples of the rare gas include helium, argon, krypton, xenon, and radon. The target is made of the above-mentioned metal.

[0037] The pressure in sputtering is, for example, 0.01 Pa or more and, for example, 10 Pa or less.

[0038] The conductive carbon layer 4 can be formed by the same method as the above-mentioned method for forming the metal underlayer 3. The conductive carbon layer 4 can be formed by preferably a dry method, more preferably a PVD method, further preferably a sputtering method, and particularly preferably a high-power pulse sputtering method or a DC pulse sputtering method.

[0039] As the target, for example, carbon, preferably sintered carbon, is used. When the conductive carbon layer 4 contains a metal, examples of the target include carbon and a metal. Specifically, examples include a first target made of carbon (preferably sintered carbon) and a second target made of a metal (preferably titanium). For example, the first target and the second target are placed independently of each other in one film formation chamber.

[0040] In addition, when the first target and the second target are disposed in the film formation chamber, the ratio of the power applied to them is controlled, thereby adjusting the proportion of metal contained in the conductive carbon layer 4.

[0041] The pulse width in the DC pulse sputtering method is generally the discharge stop time. The pulse width is, for example, 0.5 μs or more, and, for example, 1 ms or less. The frequency in the DC pulse sputtering method is, for example, 10 kHz or more, and, for example, 500 kHz or less.

[0042] The pulse width in the high-power pulse sputtering method is generally the discharge duration. The pulse width is, for example, 10 μs or more and, for example, 3 ms or less. The frequency in the high-power pulse sputtering method is, for example, 50 Hz or more and, for example, 3 kHz or less.

[0043] In this way, the electrode 1 is manufactured which comprises the resin film 2, the metal base layer 3, and the conductive carbon layer 4 in that order.

[0044] <Effects of one embodiment> In this electrode 1, one surface in the thickness direction of the conductive carbon layer 4 has an arithmetic mean roughness Ra of 1.5 nm or less and a skewness Rsk of 0.0 or more. Therefore, while noise can be suppressed, a decrease in signal intensity can also be suppressed.

[0045] Furthermore, if the conductive carbon layer 4 further contains a metal and the proportion of the metal in the conductive carbon layer 4 is 5 mass % or more and 50 mass % or less, noise can be further suppressed while the decrease in signal intensity can also be further suppressed.

[0046] Furthermore, if the metal is titanium, the adhesive strength between the conductive carbon layer 4 and the base metal layer 3 can be further increased.

[0047] <Use of electrode 1> The use of the electrode 1 is not particularly limited. For example, the electrode 1 can be used as an electrode for electrochemical measurement. Specifically, the electrode 1 is provided in an electrochemical measurement system including the electrode 1 as a working electrode. In this case, the electrode 1 is used as an electrode for electrochemical measurement. The electrochemical measurement system is used to perform, for example, cyclic voltammetry. For example, the electrochemical measurement system can be used as a blood glucose sensor. The blood glucose sensor measures the blood glucose level in the blood.

[0048] <Modification> In the following modified examples, the same components and steps as those in the above-described embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. In addition, the modified examples can achieve the same effects as those in the above-described embodiment, unless otherwise specified. Furthermore, the embodiment and its modified examples can be appropriately combined.

[0049] Although not shown, the electrode 1 of the modified example may further include a metal underlayer 3 and a conductive carbon layer 4, which are arranged in this order toward the other side in the thickness direction of the resin film 2. In the electrode 1 of this modified example, the conductive carbon layer 4, the metal underlayer 3, the resin film 2, the metal underlayer 3, and the conductive carbon layer 4 are arranged in this order toward one side in the thickness direction. The other thickness direction surface of the conductive carbon layer 4, which is arranged on the other thickness direction side of the resin film 2, has an arithmetic mean roughness Ra of 1.5 nm or less and a skewness Rsk of 0.0 or more. In this modified example, the one thickness direction surface and the other thickness direction surface of the conductive carbon layer 4 are each an example of the surface of the conductive carbon layer 4. EXAMPLES

[0050] Examples and comparative examples are shown below to more specifically explain the present invention. Note that the present invention is not limited to any examples and comparative examples. Further, specific numerical values such as the blending ratio (content ratio), physical property values, parameters, etc. used in the following description can be replaced with the upper limit values (numerical values defined as "less than or equal to" or "less than") or lower limit values (numerical values defined as "greater than or equal to" or "exceeding") of the corresponding blending ratio (content ratio), physical property values, parameters, etc. described in the above "Mode for Carrying Out the Invention".

[0051] Example 1 A resin film 2 made of 50 μm polyethylene terephthalate (PET) was prepared. The arithmetic mean roughness Ra on one surface in the thickness direction of the resin film 2 was 0.6 nm. The skewness Rsk on one surface in the thickness direction of the resin film 2 was -0.11.

[0052] Next, a metal underlayer 3 made of titanium was formed on one surface in the thickness direction of the resin film 2 by DC sputtering. The thickness of the metal underlayer 3 was 7 nm. The conditions of the DC sputtering method are as follows.

[0053] <Conditions of DC Sputtering Method> Target: Titanium Target applied power: 200 W Shape and size of the target: Cylindrical with a diameter of 2 inches Sputtering gas: Argon Pressure in the sputtering chamber: 0.3 Pa

[0054] Thereafter, a conductive carbon layer 4 was formed on one surface in the thickness direction of the metal underlayer 3 by DC pulse sputtering. The conditions of the DC pulse sputtering method are described below.

[0055] <Conditions of DC Pulse Sputtering Method> First target: Sintered carbon Second target: Titanium First target applied power: 200W Second target applied power: 10W Primary target shape and size: 2-inch diameter cylinder Secondary target shape and size: 2 inch diameter cylinder Pressure in sputtering chamber: 0.3 Pa Pulse width: 1.5μs Frequency: 150kHz

[0056] The conductive carbon layer 4 contained 10 mass % titanium. The titanium content was determined by fluorescent X-ray measurement. Note that, in the case of fluorescent X-ray measurement, the peak intensity is a mixture of the titanium contained in the conductive carbon layer 4 and the titanium used in the base metal layer 3. Therefore, the peak intensity of a sample in which only the titanium of the base metal layer 3 was previously formed under the same conditions as the sputtering method of the conductive carbon layer 4 was subtracted from the peak of the conductive carbon layer 4 to calculate the titanium content only contained in the conductive carbon layer 4. The thickness of the conductive carbon layer 4 was 10 nm. The method for measuring the thickness of the conductive carbon layer 4 will be described later.

[0057] In this way, an electrode 1 including the resin film 2, the metal base layer 3, and the conductive carbon layer 4 was manufactured.

[0058] Example 2 An electrode 1 was manufactured by the same process as in Example 1. However, in forming the conductive carbon layer 4, the DC pulse sputtering method was changed to a high-power pulse sputtering method. The average power applied to the first target was 150 W, and no power was applied to the second target. The pulse width and frequency when applying power to the first target were changed to 30 μs and 210 Hz, respectively. The pressure in the sputtering chamber was changed to 1.0 Pa. The conductive carbon layer 4 did not contain titanium and was essentially composed of carbon. The thickness of the conductive carbon layer 4 was 35 nm.

[0059] Example 3 An electrode 1 was produced by the same process as in Example 1. However, no power was applied to the second target in forming the conductive carbon layer 4. The conductive carbon layer 4 did not contain titanium and was composed substantially of carbon.

[0060] Comparative Example 1 An electrode 1 was manufactured in the same manner as in Example 1. However, in forming the conductive carbon layer 4, no power was applied to the second target. The conductive carbon layer 4 did not contain titanium and was essentially composed of carbon. The conductive carbon layer 4 had a thickness of 100 nm.

[0061] Comparative Example 2 An electrode 1 was manufactured by the same process as in Example 1. However, in forming the conductive carbon layer 4, the DC pulse sputtering method was changed to a high-power pulse sputtering method. The power applied to the first target was 150 W, and no power was applied to the second target. The pulse width and frequency when applying power to the first target were changed to 30 μs and 210 Hz, respectively. The pressure in the sputtering chamber was changed to 0.6 Pa. The conductive carbon layer 4 did not contain titanium and was essentially composed of carbon. The thickness of the conductive carbon layer 4 was 35 nm.

[0062] Comparative Example 3 An electrode 1 was produced in the same manner as in Example 3. However, the material of the resin film 2 was changed to cycloolefin resin (COP).

[0063] [evaluation] The following items were measured, and the results are shown in Table 1.

[0064] [Measurement of thickness of conductive carbon layer 4] Using X-ray reflectivity as the measurement principle, a powder X-ray diffractometer (Rigaku Corporation, "RINT-2200") was used to measure X-ray reflectivity under the following <measurement conditions>, and the data was analyzed using analysis software (Rigaku Corporation, "GXRR3") to calculate the thickness of the conductive carbon layer 4. For the analysis, a three-layer model consisting of a resin film 2 made of PET, a metal base layer 3 made of titanium, and a conductive carbon layer 4 was used under the following <analysis conditions>. The target thickness, arithmetic mean roughness Ra of the metal base layer 3, and density of 4.51 g / cm 3 The target thickness of the conductive carbon layer 4, the arithmetic mean roughness Ra of 0.5 nm, and the density of 1.95 g / cm 3 were input as initial values. Thereafter, the thickness of the conductive carbon layer 4 was analyzed by performing least squares fitting with the actually measured values.

[0065] <Measurement conditions> Measurement equipment: Powder X-ray diffraction equipment (Rigaku Corporation, "RINT-2000") Light source: Cu-Kα line (wavelength: 1,5418Å), 40kV, 40mA Optical system: Parallel beam optical system Divergence slit: 0.05mm Receiving slit: 0.05 mm Monochromatization and collimation: Using multi-layer Goebel mirrors Measurement mode: θ / 2θ scan mode Measurement range (2θ): 0.3 degrees to 2.0 degrees

[0066] <Analysis conditions> Analysis software: Rigaku's "GXRR3" Analysis method: Least squares fitting Analysis range (2θ): 2θ=0.3~2.0°

[0067] [Measurement of arithmetic mean roughness Ra and skewness Rsk of conductive carbon layer 4] Using an atomic force microscope (AFM manufactured by Bruker Japan, product name: MultiMode8), the shape of one surface in the thickness direction of the conductive carbon layer 4 was observed in accordance with JIS R1683:2014. From the observation results, the arithmetic mean roughness Ra and the degree of skewness Rsk defined in JIS B0601:2013 were determined for one surface in the thickness direction of the conductive carbon layer 4.

[0068] [Electrode evaluation] <Ferricyanide activity measurement> (Inhibition of decrease in signal intensity) An insulating tape was attached to one surface in the thickness direction of the conductive carbon layer 4. The insulating tape had a hole with a diameter of 2 mm. As a result, the electrode area was 0.0314 cm 2 This resulted in the electrode being prepared as a working electrode. The working electrode was inserted into a potassium chloride solution in which K4[Fe(CN)6] was dissolved, and connected to a potentiostat (IVIUM, pocketSTAT). The concentration of potassium chloride in the solution was 1.0 mol / L. The concentration of K4[Fe(CN)6] in the solution was 1.0 mol / L. In the same manner as above, a reference electrode (Ag / AgCl) and a counter electrode (Pt) were inserted into the potassium chloride solution and connected to the potentiostat. Then, cyclic voltammetry was performed in the potential range of -0.1 V to 0.5 V at a scan rate of 0.1 V / sec. The redox potential difference ΔEp was obtained as the ferricyanide activity value.

[0069] The signal intensity of electrode 1 was evaluated based on the ferricyanide activity value according to the following criteria. ○ The ferricyanide activity value was less than 150mV. × The ferricyanide activity value was 150mV or more.

[0070] The lower the ferricyanide activity value, the better the suppression of the decrease in the signal intensity of the electrode 1.

[0071] <Capacitance value measurement> (Noise suppression) An insulating tape was attached to one surface in the thickness direction of the conductive carbon layer 4. The insulating tape had a hole with a diameter of 2 mm. As a result, the electrode area was 0.0314 cm 2 This resulted in the electrode being prepared as a working electrode. The working electrode was inserted into a 1.0 mol / L potassium chloride solution and connected to a potentiostat (pocketSTAT, IVIUM). Similarly, a reference electrode (Ag / AgCl) and a counter electrode (Pt) were also inserted into the potassium chloride solution and connected to the potentiostat. Next, cyclic voltammetry was performed in the potential range from 0 V to 0.5 V at a scan rate of 0.01 V / sec. The capacitance value was calculated by substituting the following equation:

[0072] Capacitance value = (sum of absolute values ​​of two current values ​​at 0.25V) [A] / 2 × 0.01 [V / sec] / 0.0314 [cm 2 ]

[0073] The unit of capacitance value is [A] / [V / sec] / [cm 2 ] and [F / cm 2 ] is the same as

[0074] The noise suppression ability of electrode 1 was evaluated based on the capacitance value according to the following criteria. Capacitance value is 15μF / cm 2 It was less than. × Capacitance value is 15μF / cm 2 That was all.

[0075] The lower the capacitance value, the better the noise of electrode 1 is suppressed.

[0076] [Table 1]

[0077] The above invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be interpreted as being limited. Modifications of the present invention that are obvious to those skilled in the art are included in the scope of the following claims. [Industrial Applicability]

[0078] The electrodes are used in electrochemical measurements. [Explanation of symbols]

[0079] 1 electrode 2. Resin film 3 Metal base layer 4 Conductive carbon layer

Claims

1. A resin film, a metal base layer, and a conductive carbon layer are provided in this order in a thickness direction, An electrode, wherein the surface of the conductive carbon layer has an arithmetic mean roughness Ra of 1.50 nm or less and a degree of skewness Rsk of 0.00 or more.

2. The conductive carbon layer contains a metal, 2. The electrode according to claim 1, wherein the conductive carbon layer has a metal content of 5% by mass or more and 50% by mass or less.

3. The electrode of claim 1 , wherein the metal is titanium.

4. The electrode of claim 2 wherein the metal is titanium.

5. 10. The electrode of claim 1, which is an electrode for electrochemical measurements.

6. The electrode according to claim 2 , which is an electrode for electrochemical measurements.

7. The electrode according to claim 3 , which is an electrode for electrochemical measurements.

8. The electrode according to claim 4 , which is an electrode for electrochemical measurements.

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