Sheet electrode

Abstract

To provide a sheet electrode with excellent wearability. To improve wearing comfort, such as reducing discomfort. Furthermore, as an indicator of wearability, it suppresses changes in skin condition on the contact surface, such as redness of the skin. [Solution] The present invention provides a sheet electrode comprising a sheet-like conductive elastomer layer and a plurality of through holes P formed in the conductive elastomer layer, wherein (i) a plurality of through holes P30 are formed in the conductive elastomer layer 20 having a biocompatible surface, and / or (ii) a plurality of through holes Q50 are formed in the flexible substrate 10 around the biocompatible surface, thereby suppressing a decrease in the attachability of the sheet electrode 100.

Description

Technical Field

[0001] The present invention relates to a sheet electrode.

Background Art

[0002] Various developments have been made on sheet electrodes so far. As this type of technology, for example, the technology described in Patent Document 1 is known. Patent Document 1 describes that holes are formed at the positions of the eyes and nose when a bioelectrical stimulation device is attached to the face.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, as a result of investigations by the present inventors, it has been found that there is room for improvement in terms of wearability in the bioelectrical stimulation device as described in Patent Document 1 above.

Means for Solving the Problems

[0005] [[ID=四十二]]

[0006]

[0006] According to one aspect of the present invention, the following sheet electrode 100 is provided. <00(0)0118>1. A sheet-like conductive elastomer layer, and A sheet electrode comprising a plurality of through holes P formed in the conductive elastomer layer. 2. The sheet electrode according to 1., <00001(0)1>Comprising a flexible substrate that holds the conductive elastomer layer on at least one surface, A sheet electrode having a structure in which at least one of the multiple through holes P penetrates the flexible substrate. 3. Flexible base material and A sheet-like conductive elastomer layer is held on at least one surface of the flexible substrate, A sheet electrode comprising a plurality of through-holes Q that penetrate the flexible substrate but do not penetrate the conductive elastomer layer. 4. A sheet electrode as described in 1. or 2., A sheet electrode in which, when viewed from the vertical direction of the surface of the conductive elastomer layer, the maximum width D1 of the through-hole P is 0.1 mm or more and 10 mm or less. 5. A sheet electrode as described in 1. or 2., A sheet electrode having a conductive elastomer layer with a thickness of 0.005 mm or more and 2 mm or less. 6. A sheet electrode described in any one of 1, 2, 4, or 5, When the maximum width (mm) of the through-hole P as viewed from the vertical direction on the surface of the conductive elastomer layer is D1, and the thickness (mm) of the conductive elastomer layer is H, A sheet electrode with a D1 / H ratio of 0.05 to 2000. 7. A sheet electrode described in any one of 1.2.4.~6., A sheet electrode in which the minimum pitch D2 between the centers of the multiple through holes P is 0.1 mm or more and 10 mm or less. 8. A sheet electrode described in any one of 1.2.4.~7., A sheet electrode in which, when viewed from the vertical direction of the surface of the conductive elastomer layer, the shape of the through-hole P is circular, elliptical, or a polygon without corners. 9. A sheet electrode described in any one of 1.2.4.~8., A sheet electrode in which, when viewed from the vertical direction of the surface of the conductive elastomer layer, the area surrounded by the outer edge of the sheet electrode is A1, the area surrounded by the outer edge of the conductive elastomer layer is A2 (however, including the region in which the through-holes P are formed), and the total area of ​​the multiple through-holes P is A3, such that 10% ≤ [(A2-A3) / A1] × 100 < 100%. 10. A sheet electrode described in any one of 1.2.4.~9., The number of through-holes P in the conductive elastomer layer is 0.1 holes / cm². 2 More than 2500 pieces / cm 2 The sheet electrode is as follows. 11. A sheet electrode described in any one of 1.2.4.~10. A sheet electrode in which the minimum distance D3 between the ends of the multiple through holes P and the ends of the conductive elastomer layer is 0.1 mm or more. 12. A sheet electrode described in any one of items 1 to 11, A sheet electrode having a tensile strength of 0.5 MPa or more for the conductive elastomer layer. 13. A sheet electrode described in any one of items 1 to 12, A sheet electrode having a break elongation of 10% or more in the conductive elastomer layer. 14. A sheet electrode described in any one of items 1 to 13, A sheet electrode wherein the conductive filler content in the conductive elastomer layer is 50% by mass or more and 90% by mass or less. 15. A sheet electrode described in any one of items 1 to 14, A sheet electrode in which the conductive elastomer layer includes conductive silicone rubber. [Effects of the Invention]

[0007] According to the present invention, a sheet electrode with excellent attachability is provided. [Brief explanation of the drawing]

[0008] [Figure 1]This is a schematic top view showing an example of the configuration of a sheet electrode according to this embodiment. [Figure 2] This is a schematic cross-sectional view showing an example of the configuration of a sheet electrode according to this embodiment. Note that Figure 2(b) is a cross-sectional view of section AA in Figure 1. [Modes for carrying out the invention]

[0009] Embodiments of the present invention will be described below with reference to the drawings. In all drawings, similar components are denoted by the same reference numerals, and their descriptions are omitted as appropriate. Also, the drawings are schematic diagrams and do not correspond to the actual dimensional ratios.

[0010] The outline of the sheet electrode of this embodiment will be described.

[0011] Figure 1 is a schematic top view showing an example of the configuration of the sheet electrode 100. Figure 2(B) is a cross-sectional view AA of the sheet electrode 100 in Figure 1, and Figures 2(A) and (C) are schematic cross-sectional views showing another example of the sheet electrode 100.

[0012] The sheet electrode 100 of this embodiment has at least a conductive elastomer layer 20 and is provided with through holes that penetrate both the front and back surfaces. Specifically, there are the following first and second embodiments.

[0013] The sheet electrode 100 of the first embodiment is A sheet-like conductive elastomer layer 20, The device comprises a plurality of through holes P30 formed in a conductive elastomer layer 20.

[0014] The sheet electrode 100 of the first embodiment is When a flexible substrate 10 is provided that holds a conductive elastomer layer 20 on at least one surface, At least one of the multiple through holes P30 has a structure that penetrates the flexible substrate 10.

[0015] The sheet electrode 100 of the second embodiment is Flexible base material 10, A sheet-like conductive elastomer layer 20 is held on at least one surface of the flexible substrate 10, It comprises a plurality of through-holes Q50 that penetrate the flexible substrate 10 but do not penetrate the conductive elastomer layer 20.

[0016] The sheet electrode 100 of this embodiment can be applied to various uses, but it is preferably used as a bioelectrode. In the sheet electrode 100, which is a bioelectrode, the surface of the conductive elastomer layer 20 becomes the biocontact surface that comes into contact with the subject's body. The sheet electrode 100 is attached to the subject's body, and the subject's biopotential can be measured.

[0017] According to the inventors' findings, if the biological contact surface of the sheet electrode 100 remains in contact with the surface of the subject's skin or other surface for an extended period, there is a risk that the wearability may decrease due to stuffiness.

[0018] Based on these findings, further investigation revealed that the deterioration of the attachmentability of the sheet electrode 100 can be suppressed by (i) forming multiple through-holes P30 in the conductive elastomer layer 20 having a bio-contact surface, and / or (ii) forming multiple through-holes Q50 in the flexible substrate 10 around the bio-contact surface.

[0019] In this specification, wearability can be indicated by the degree of discomfort or other factors related to the wearing experience. Furthermore, the degree of variation in skin condition on the contact surface, such as redness, may be substituted or added to the indicator of wearability.

[0020] Bioelectric potentials are not particularly limited, but examples include electrocardiograms, muscle and skin potentials, and electroencephalograms.

[0021] The configurations of the sheet electrode 100 in this embodiment will be described in detail below.

[0022] The sheet electrode 100 has through holes P30 formed in the conductive elastomer layer 20. The sheet electrode 100 in Figure 2(A) has a structure that includes at least a conductive elastomer layer 20 and does not have a flexible base material 10. The multiple through holes P30 shown in Figure 2(A) may be holes that penetrate only the conductive elastomer layer 20. The sheet electrode 100 in Figure 2(B) has a structure comprising at least a flexible substrate 10 and a conductive elastomer layer 20. The multiple through holes P30 shown in Figure 2(B) may be holes that penetrate the flexible substrate 10 and the conductive elastomer layer 20. If the sheet electrode 100 has a structure in which layers other than the flexible substrate 10 and the conductive elastomer layer 20 are laminated in the thickness direction of these layers, the multiple through holes P30 may be configured to penetrate all layers and penetrate both the front and back surfaces of the sheet electrode 100. The multiple through holes P30 are independent of each other and do not need to communicate within the conductive elastomer layer 20.

[0023] When viewed from the vertical direction of the surface of the conductive elastomer layer 20 (hereinafter defined as a top view), as shown in Figure 1, the maximum width D1 of the through-hole P30 is, for example, 0.1 mm to 10 mm, preferably 1 mm to 8 mm, and more preferably 2 mm to 6 mm. Above the lower limit, air permeability can be improved. Below the upper limit, electrocardiogram measurement performance can be improved. The maximum width refers to the widest possible width of the through-hole P30 when viewed from above. Furthermore, the maximum width D1 of each of the multiple through holes P30 may be the same or different from one another. In this specification, "identical" means that dimensional variations in the manufacturing process are to be tolerated. In this specification, "~" indicates that it includes both upper and lower limits unless otherwise specified.

[0024] As shown in Figure 1, in a top view of the conductive elastomer layer 20, the shape of the through-hole P30 is, for example, circular, elliptical, or a polygon without corners. Among these, circular or elliptical shapes are preferred from the viewpoint of suppressing the occurrence of a point of failure in the conductive elastomer layer 20 when the sheet electrode 100 is stretched and / or deformed. The shapes of the multiple through holes P30 may be identical or different from each other.

[0025] Furthermore, in a cross-sectional view of the conductive elastomer layer 20 in the thickness direction, the shape of the through-hole P30 may be approximately rectangular, as shown in Figure 2(B). The opening width of the through-hole P30 may be the same on the upper and lower sides, or one of the opening widths may be relatively larger.

[0026] The number of through-holes P30 in the conductive elastomer layer 20 is, for example, 0.1 holes / cm². 2 More than 2500 pieces / cm 2 Preferably 0.3 pieces / cm 2 ~1000 pieces / cm 2 more preferably 0.5 pieces / cm 2 ~100 pieces / cm 2 Therefore, a value above the lower limit improves breathability. A value below the upper limit improves durability.

[0027] In a top view of the conductive elastomer layer 20, as shown in Figure 1, the minimum pitch D2 between the centers of the multiple through holes P30 is, for example, 0.1 mm to 10 mm, preferably 0.5 mm to 9 mm, and more preferably 1 mm to 8 mm. A value above the lower limit improves durability. A value below the upper limit improves breathability.

[0028] In a top view of the conductive elastomer layer 20, as shown in Figure 1, the lower limit of the minimum distance D3 between the ends of the multiple through holes P30 and the ends of the conductive elastomer layer 20 is, for example, 0.1 mm or more, preferably 0.5 mm or more, and more preferably 1 mm or more. This improves durability. On the other hand, the upper limit of the minimum distance D3 is not particularly limited, but it may be 40mm or less, 30mm or less, 20mm or less, or 10mm or less.

[0029] The thickness of the conductive elastomer layer 20 is, for example, 0.005 mm to 2 mm, preferably 0.01 mm to 1.9 mm, and more preferably 0.04 mm to 1.8 mm. A thickness above the lower limit improves conductivity. A thickness below the upper limit improves wearability.

[0030] D1 is the maximum width (mm) of the through-hole P30 when viewed from the vertical direction (top view) of the surface of the conductive elastomer layer 20, and H is the thickness (mm) of the conductive elastomer layer 20 in the thickness direction. D1 / H is, for example, 0.05 to 2000, preferably 0.1 to 1000, and more preferably 1 to 500. A value above the lower limit improves conductivity. A value below the upper limit improves wearability.

[0031] When viewed from the vertical direction of the surface of the conductive elastomer layer 20 (top view), the area surrounded by the outer edge of the sheet electrode 100 is A1, the area surrounded by the outer edge of the conductive elastomer layer 20 is A2 (including the area where the through-holes P30 are formed), and the total area of ​​the multiple through-holes P30 is A3. As shown in Figure 1, A1 may include the area of ​​the flexible substrate 10 (including the area where the conductive elastomer layer 20 is formed). Furthermore, if multiple conductive elastomer layers 20 are spaced apart from each other on the sheet electrode 100, A2 is the sum of the areas of the multiple conductive elastomer layers 20. The sheet electrode 100 may be configured such that 10% ≤ [(A2-A3) / A1] × 100 < 100%. (A2-A3) / A1 represents the ratio of the effective electrode area that can come into contact with the object being measured. The lower limit of [(A2-A3) / A1]×100 is, for example, 10% or more, preferably 20% or more, and more preferably 30% or more. This improves the accuracy of electrocardiogram measurement. The upper limit of [(A2-A3) / A1]×100 is, for example, less than 100%, preferably 95% or less, and more preferably 90% or less. Keeping it below the upper limit improves breathability.

[0032] The lower limit of the tensile strength of the conductive elastomer layer 20 is, for example, 0.5 MPa or more, preferably 1 MPa or more, and more preferably 2 MPa or more. This improves durability. The upper limit of the tensile strength of the conductive elastomer layer 20 is not particularly limited, but it may be 20 MPa or less, 10 MPa or less, or 5 MPa or less.

[0033] The lower limit of the elongation at break of the conductive elastomer layer 20 is, for example, 10% or more, preferably 50% or more, and more preferably 100% or more. This improves durability. The upper limit of the elongation at break of the conductive elastomer layer 20 is not particularly limited, but it may be 800% or less, 600% or less, or 500% or less.

[0034] In this embodiment, as a method for measuring the characteristics of each component of the sheet electrode 100, each component may be used as a test piece as is, or the components may be cut into a predetermined shape or multiple components may be stacked to obtain a test piece of a predetermined thickness. Alternatively, the elastomer used for each component, such as silicone rubber (insulating silicone rubber or conductive silicone rubber), may be used for measurement.

[0035] (Procedure for measuring tensile strength) Using elastomer, a dumbbell-shaped No. 3 test specimen was prepared in accordance with JIS K6251 (2004), and the tensile strength of the dumbbell-shaped No. 3 test specimen was measured at 25°C.

[0036] (Measurement conditions for elongation at break) Using elastomer, a dumbbell-shaped No. 3 test specimen was prepared in accordance with JIS K6251 (2004), and the elongation at break at 25°C was measured for the obtained dumbbell-shaped No. 3 test specimen. The elongation at break was calculated as [gauge displacement (mm)] ÷ [initial gauge distance (20 mm)] × 100.

[0037] The flexible base material 10 is not particularly limited as long as it is a base material that can be stretched and / or bent, but for example it may be composed of a fibrous base material or an elastomer base material.

[0038] The fibrous base material can be any known fibrous base material, but it may be composed of either an insulating material or a conductive material, or both. The structure of the fibrous base material is not limited, but from the viewpoint of flexibility, woven or knitted fabrics may be used.

[0039] The elastomer substrate may be composed of an insulating elastomer as described later. Furthermore, the elastomer substrate may be a porous elastomer substrate, or an elastomer substrate with irregularities on its surface, etc.

[0040] The upper limit of the thickness of the flexible substrate 10 can be set according to the application, for example, it may be 10 mm or less, preferably 1 mm or less, but more preferably 600 μm or less from the viewpoint of wearable device applications. By setting it to 600 μm or less, a thin film sheet-like wearable bioelectrode can be realized. The lower limit of the thickness of the flexible substrate 10 is, from the viewpoint of mechanical strength, for example, 10 μm or more, preferably 50 μm or more, and more preferably 100 μm or more.

[0041] The flexible substrate 10 may have an impregnation layer in which a portion of the conductive elastomer layer 20 is impregnated, but it may not have an impregnation layer.

[0042] The shape of the flexible substrate 10 when viewed from the vertical direction of the surface is not particularly limited, but in the case of wearable device applications, it may have a shape that can be worn by a subject.

[0043] The sheet electrode 100 in Figure 2(C) has a structure comprising at least a flexible substrate 10 and a conductive elastomer layer 20. The multiple through-holes Q50 shown in Figure 2(C) penetrate at least the flexible substrate 10 but do not penetrate the conductive elastomer layer 20. In other words, in a top view of the sheet electrode 100, the multiple through-holes Q50 are formed in the region where the flexible substrate 10 is exposed, but not in the region where the conductive elastomer layer 20 is exposed. Although the sheet electrode 100 in Figure 2(B) does not have multiple through holes Q50, a modified example may further have multiple through holes Q50.

[0044] Furthermore, the number of through holes Q50 formed in the flexible substrate 10, the maximum width in a top view, the shape in a top view, and the shape in a cross-sectional view in the thickness direction of the flexible substrate 10 can be the same as those exemplified for the through holes P30.

[0045] The following describes an example of a method for manufacturing the sheet electrode 100. An example of a manufacturing method may include the steps of forming an insulating elastomer layer, forming a conductive elastomer layer using a conductive paste on the insulating elastomer layer, and forming multiple through holes that penetrate the insulating elastomer layer and the conductive elastomer layer, or only the insulating elastomer layer. Another example of a manufacturing method may include the step of forming a conductive elastomer layer on a support sheet, then forming multiple through holes in it, and separating the conductive elastomer layer from the support sheet. Each process may be independent, but they may also overlap or be carried out simultaneously.

[0046] For forming the insulating elastomer layer, a conventional molding method such as calendering or compression molding may be used with an elastomer composition that does not contain conductive fillers, or a printing method may be used with such an insulating paste.

[0047] The above-mentioned elastomer composition is an elastomer or a composition containing components for forming an elastomer, and an uncured thermosetting elastomer composition is preferred, with a silicone rubber-based curable composition described later being more preferred.

[0048] Through-holes can be formed using methods such as molds, cutting, or, in the case of paste, a mask with openings.

[0049] A printing method using a conductive paste containing a conductive filler and the above-mentioned elastomer composition is used, but is not limited to, the formation of the conductive elastomer layer.

[0050] A specific example of forming a conductive elastomer layer is to apply a conductive paste and allow it to dry. Then, the coating is cured to form a conductive elastomer layer. The coating can be in the form of a sheet or a pattern. Drying conditions can be appropriately set depending on the type and amount of solvent in the conductive paste, but for example, the drying temperature can be set to 120°C to 180°C and the drying time to 1 minute to 30 minutes. The curing conditions can be appropriately set depending on the elastomer composition in the conductive paste and its content. However, if the elastomer composition is a silicone rubber-based curable composition, for example, the curing temperature can be set to 120°C to 220°C and the curing time to 1 to 3 hours.

[0051] The insulating elastomer layer and the conductive elastomer layer may each be fixed to each other by known fixing methods such as adhesives or adhesive sheet methods, but it is preferable that the solvent contained in the conductive paste immerses a portion of the insulating elastomer layer, causing the insulating elastomer layer and the conductive elastomer layer to fuse together and be fixed in place.

[0052] If necessary, a mask having a predetermined opening pattern shape may be placed on at least a portion of the surface of the conductive elastomer layer, and an insulating paste may be applied through the mask to form an insulating layer (stretchable cover portion).

[0053] The following describes the elastomer material used for the sheet electrode 100. The conductive elastomer contained in the conductive elastomer layer 20 and the insulating elastomer used in the flexible substrate 10 each refer to stretchable elastic bodies. Examples of elastomers that can be used include silicone rubber, urethane rubber, fluororubber, nitrile rubber, acrylic rubber, styrene rubber, chloroprene rubber, and ethylene propylene rubber. Among these, it is preferable to use one or more thermosetting elastomers selected from the group consisting of silicone rubber, urethane rubber, and fluororubber.

[0054] The insulating elastomer may consist of an elastomer alone, or it may consist of an elastomer and a non-conductive filler. The insulating elastomer is preferably made of silicone rubber, specifically insulating silicone rubber. The insulating elastomer does not contain a conductive filler, but may contain a non-conductive filler. Silicone rubber is chemically stable, has excellent mechanical strength, and is highly biocompatible, making it one of the best elastomers available.

[0055] The conductive elastomer may be configured to include an elastomer and a conductive filler. The conductive elastomer is preferably a conductive silicone rubber containing silicone rubber and a conductive filler. This conductive elastomer may also contain a non-conductive filler. By using conductive silicone rubber, both elasticity and conductivity can be enhanced.

[0056] The conductive filler mentioned above may include, for example, one or more selected from the group consisting of powdered or fibrous metal-based fillers, carbon-based fillers (conductive carbon materials), metal oxide fillers, and metal-plated fillers.

[0057] As the non-conductive filler mentioned above, known materials can be used, but for example, silica particles, silicone rubber particles, talc, etc., may be used. These may be used individually or in combination of two or more. Among these, silica particles may also be included.

[0058] In this embodiment, the insulating elastomer and the conductive elastomer may each contain the same elastomer or different elastomers, but it is preferable that they all contain silicone rubber, and more preferably that they contain a cured product of a silicone rubber-based curable composition containing a vinyl group-containing organopolysiloxane.

[0059] In this specification, "containing the same silicone rubber" means that the silicone rubber-based curable composition contains at least the same type of vinyl group-containing linear organopolysiloxane, and may further contain one or more selected from the group consisting of the same type of crosslinking agent, the same type of nonconductive filler, the same type of silane coupling agent, and the same type of catalyst.

[0060] A linear organopolysiloxane containing the same type of vinyl group is defined as one that contains at least the same vinyl group as a functional group and has a linear structure, even if the amount of vinyl group in the molecule, the molecular weight distribution, or the amount added differs.

[0061] Similar crosslinking agents only need to have a common structure, such as a linear or branched structure, and may have different molecular weight distributions and functional groups, as well as different amounts added.

[0062] Non-conductive fillers of the same type only need to have at least common constituent materials, and may differ in particle size, specific surface area, surface treatment agent, or the amount of such agent added.

[0063] Similar silane coupling agents only need to have at least one common functional group; other functional groups in the molecule and the amount added may differ.

[0064] Catalysts of the same type only need to have at least common constituent materials; they may contain different compositions, and the amounts of these compositions added may differ.

[0065] A silicone rubber-based curable composition comprising the same silicone rubber may further contain one or more different types selected from the group consisting of vinyl group-containing linear organopolysiloxanes, crosslinking agents, nonconductive fillers, silane coupling agents, and catalysts.

[0066] The components of the above-mentioned silicone rubber-based curable composition will be described in detail below.

[0067] The silicone rubber-based curable composition of this embodiment may contain a vinyl group-containing organopolysiloxane (A). The vinyl group-containing organopolysiloxane (A) is a polymer that forms the main component of the silicone rubber-based curable composition of this embodiment.

[0068] The vinyl group-containing organopolysiloxane (A) may include a vinyl group-containing linear organopolysiloxane (A1) having a linear structure.

[0069] The above vinyl group-containing linear organopolysiloxane (A1) has a linear structure and contains vinyl groups, which serve as crosslinking points during curing.

[0070] The vinyl group content of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but it is preferable that it has two or more vinyl groups in the molecule and that the content is 15 mol% or less. This optimizes the amount of vinyl groups in the vinyl group-containing linear organopolysiloxane (A1) and ensures the formation of a network with the components described later.

[0071] In this specification, the vinyl group content refers to the mole percent of vinyl group-containing siloxane units when the total number of units constituting the vinyl group-containing linear organopolysiloxane (A1) is considered to be 100 mol%. However, it is assumed that there is one vinyl group per vinyl group-containing siloxane unit.

[0072] In addition, the degree of polymerization of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but for example, it is preferably in the range of about 1000 to 10000, more preferably in the range of about 2000 to 5000. The degree of polymerization can be determined, for example, as the number average degree of polymerization (or number average molecular weight) in terms of polystyrene in GPC (gel permeation chromatography) with chloroform as the developing solvent.

[0073] Furthermore, the specific gravity of the vinyl group-containing linear organopolysiloxane (A1) is not particularly limited, but it is preferably in the range of about 0.9 to 1.1.

[0074] By using the vinyl group-containing linear organopolysiloxane (A1) having a degree of polymerization and specific gravity within the above ranges, it is possible to improve the heat resistance, flame retardancy, chemical stability, etc. of the resulting silicone rubber.

[0075] The vinyl group-containing linear organopolysiloxane (A1) preferably has a structure represented by the following formula (1).

[0076]

Chemical formula

[0077] In formula (1), R 1 is a substituted or unsubstituted alkyl group, alkenyl group, aryl group having 1 to 10 carbon atoms, or a hydrocarbon group combining these. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a propyl group, etc., and among them, a methyl group is preferable. Examples of the alkenyl group having 1 to 10 carbon atoms include a vinyl group, an allyl group, a butenyl group, etc., and among them, a vinyl group is preferable. Examples of the aryl group having 1 to 10 carbon atoms include a phenyl group, etc.

[0078] Also, R 2The C1-C10 alkyl group is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, or a hydrocarbon group having 1 to 10 carbon atoms. Examples of C1-C10 alkyl groups include methyl, ethyl, and propyl groups, with methyl being preferred. Examples of C1-C10 alkenyl groups include vinyl, allyl, and butenyl groups. An example of a C1-C10 aryl group is the phenyl group.

[0079] Also, R 3 This group is a substituted or unsubstituted alkyl group, aryl group, or hydrocarbon group having 1 to 8 carbon atoms. Examples of alkyl groups having 1 to 8 carbon atoms include methyl, ethyl, and propyl groups, with methyl being preferred. An example of an aryl group having 1 to 8 carbon atoms is the phenyl group.

[0080] Furthermore, R in equation (1) 1 and R 2 Examples of substituents include methyl groups and vinyl groups, and R 3 Examples of substituents include methyl groups.

[0081] Note that in equation (1), multiple R 1 These are independent of each other, and may be different from each other or the same. Furthermore, R 2 , and R 3 The same applies to this matter.

[0082] Furthermore, m and n are the number of repeating units constituting the vinyl group-containing linear organopolysiloxane (A1) represented by formula (1), where m is an integer from 0 to 2000 and n is an integer from 1000 to 10000. Preferably, m is from 0 to 1000 and n is from 2000 to 5000.

[0083] Furthermore, a specific structure of the vinyl group-containing linear organopolysiloxane (A1) represented by formula (1) is, for example, the one represented by the following formula (1-1).

[0084] [ka]

[0085] In formula (1-1), R 1 and R 2 Each of these is independently either a methyl group or a vinyl group, and at least one of them is a vinyl group.

[0086] The vinyl group-containing linear organopolysiloxane (A1) may include a first vinyl group-containing linear organopolysiloxane (A1-1) having two or more vinyl groups in the molecule and containing 0.4 mol% or less. The amount of vinyl groups in the first vinyl group-containing linear organopolysiloxane (A1-1) may be 0.1 mol% or less.

[0087] Furthermore, the vinyl group-containing linear organopolysiloxane (A1) may contain a first vinyl group-containing linear organopolysiloxane (A1-1) and a second vinyl group-containing linear organopolysiloxane (A1-2) having a vinyl group content of 0.5 to 15 mol%.

[0088] By combining a first vinyl group-containing linear organopolysiloxane (A1-1) and a second vinyl group-containing linear organopolysiloxane (A1-2) with a high vinyl group content, the vinyl groups can be unevenly distributed, allowing for more effective formation of crosslink density variations within the crosslinking network of the silicone rubber. As a result, the tear strength of the silicone rubber can be more effectively increased.

[0089] Specifically, it is preferable to use, for example, a first vinyl group-containing linear organopolysiloxane (A1-1) having two or more units in the molecule where R1 is a vinyl group and / or R2 is a vinyl group in the above formula (1-1), and containing 0.4 mol% or less of these units, and a second vinyl group-containing linear organopolysiloxane (A1-2) containing 0.5 to 15 mol% of units where R1 is a vinyl group and / or R2 is a vinyl group.

[0090] Furthermore, the first vinyl group-containing linear organopolysiloxane (A1-1) preferably has a vinyl group content of 0.01 to 0.2 mol%. Also, the second vinyl group-containing linear organopolysiloxane (A1-2) preferably has a vinyl group content of 0.8 to 12 mol%.

[0091] Furthermore, when a first vinyl group-containing linear organopolysiloxane (A1-1) and a second vinyl group-containing linear organopolysiloxane (A1-2) are combined, the ratio of (A1-1) to (A1-2) is not particularly limited, but for example, a weight ratio of (A1-1):(A1-2) of 50:50 to 95:5 is preferred, and a weight ratio of 80:20 to 90:10 is more preferred.

[0092] Furthermore, the first and second vinyl group-containing linear organopolysiloxanes (A1-1) and (A1-2) may be used individually or in combination of two or more types.

[0093] Furthermore, the vinyl group-containing organopolysiloxane (A) may also include a vinyl group-containing branched organopolysiloxane (A2) having a branched structure.

[0094] <<Organohydrogenpolysiloxane (B)>> The silicone rubber-based curable composition of this embodiment may contain organohydrogenpolysiloxane (B). Organohydrogenpolysiloxanes (B) are classified into linear organohydrogenpolysiloxanes (B1) having a linear structure and branched organohydrogenpolysiloxanes (B2) having a branched structure, and may include either one or both of these.

[0095] Linear organohydrogenpolysiloxane (B1) is a polymer having a linear structure and a structure in which hydrogen is directly bonded to Si (≡Si-H), and undergoes a hydrosilylation reaction with vinyl groups of vinyl group-containing organopolysiloxane (A), as well as vinyl groups of components blended into silicone rubber-based curable compositions, thereby crosslinking these components.

[0096] The molecular weight of the linear organohydrogenpolysiloxane (B1) is not particularly limited, but for example, it is preferable that the weight-average molecular weight is 20,000 or less, and more preferably 1,000 or more and 10,000 or less.

[0097] The weight-average molecular weight of linear organohydrogenpolysiloxane (B1) can be measured, for example, by converting it to polystyrene equivalent in GPC (gel permeation chromatography) using chloroform as the developing solvent.

[0098] Furthermore, it is preferable that the linear organohydrogenpolysiloxane (B1) does not typically have vinyl groups. This effectively prevents the crosslinking reaction from proceeding within the linear organohydrogenpolysiloxane (B1) molecule.

[0099] As the linear organohydrogenpolysiloxane (B1) described above, one having the structure represented by the following formula (2) is preferably used.

[0100] [ka]

[0101] In formula (2), R4 The group is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, a hydrocarbon group formed by combining these groups, or a hydride group, all having 1 to 10 carbon atoms. Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, and propyl groups, with methyl being preferred. Examples of alkenyl groups having 1 to 10 carbon atoms include vinyl, allyl, and butenyl groups. An example of an aryl group having 1 to 10 carbon atoms is the phenyl group.

[0102] Also, R 5 The group is a substituted or unsubstituted alkyl group, alkenyl group, aryl group, hydrocarbon group, or hydride group having 1 to 10 carbon atoms. Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, and propyl groups, with methyl being preferred. Examples of alkenyl groups having 1 to 10 carbon atoms include vinyl, allyl, and butenyl groups. An example of an aryl group having 1 to 10 carbon atoms is the phenyl group.

[0103] Note that in equation (2), multiple R 4 These are independent of each other, and may be different from each other or the same. 5 The same applies to multiple Rs. 4 and R 5 Of these, at least two are hydride groups.

[0104] Also, R 6 R is a substituted or unsubstituted alkyl group, aryl group, or hydrocarbon group having 1 to 8 carbon atoms. Examples of alkyl groups having 1 to 8 carbon atoms include methyl, ethyl, and propyl groups, with methyl being preferred. An example of an aryl group having 1 to 8 carbon atoms is the phenyl group. Multiple R 6 These are independent of each other, and may be different from each other or the same.

[0105] Note that R in equation (2) 4 ,R 5 ,R6 Examples of substituents include methyl groups and vinyl groups, and methyl groups are preferred from the viewpoint of preventing intramolecular crosslinking reactions.

[0106] Furthermore, m and n are the number of repeating units constituting the linear organohydrogenpolysiloxane (B1) represented by formula (2), where m is an integer from 2 to 150 and n is an integer from 2 to 150. Preferably, m is an integer from 2 to 100 and n is an integer from 2 to 100.

[0107] Furthermore, linear organohydrogenpolysiloxane (B1) may be used alone or in combination of two or more types.

[0108] The branched organohydrogenpolysiloxane (B2) has a branched structure, which allows it to form regions with high crosslink density, and it is a component that greatly contributes to the formation of a dense-sparse crosslink structure in the silicone rubber system. Also, similar to the linear organohydrogenpolysiloxane (B1) described above, it has a structure in which hydrogen is directly bonded to Si (≡Si-H), and it is a polymer that undergoes hydrosilylation reactions with the vinyl groups of vinyl group-containing organopolysiloxane (A) as well as the vinyl groups of components blended into the silicone rubber curable composition, thereby crosslinking these components.

[0109] Furthermore, the specific gravity of branched organohydrogenpolysiloxane (B2) is in the range of 0.9 to 0.95.

[0110] Furthermore, it is preferable that the branched organohydrogenpolysiloxane (B2) does not typically have vinyl groups. This effectively prevents the crosslinking reaction from proceeding within the branched organohydrogenpolysiloxane (B2) molecule.

[0111] Furthermore, the branched organohydrogenpolysiloxane (B2) is preferably the one shown in the following average composition formula (c).

[0112] Average composition formula (c) (Ha (R 7 ) 3-a SiO 1 / 2 ) m (SiO 4 / 2 ) n (In equation (c), R 7 H is a monovalent organic group, a is an integer in the range of 1 to 3, and m is H a (R 7 ) 3-a SiO 1 / 2 The number of units, n is SiO 4 / 2 (The number of units)

[0113] In equation (c), R 7 The group is a monovalent organic group, preferably a substituted or unsubstituted alkyl group, aryl group, or hydrocarbon group having 1 to 10 carbon atoms. Examples of alkyl groups having 1 to 10 carbon atoms include methyl, ethyl, and propyl groups, with methyl being preferred. An example of an aryl group having 1 to 10 carbon atoms is the phenyl group.

[0114] In formula (c), a is the number of hydride groups (hydrogen atoms directly bonded to Si), and is an integer in the range of 1 to 3, preferably 1.

[0115] Also, in equation (c), m is H a (R 7 ) 3-a SiO 1 / 2 The number of units, n is SiO 4 / 2 It is the number of units.

[0116] Branched organohydrogenpolysiloxane (B2) has a branched structure. Linear organohydrogenpolysiloxane (B1) and branched organohydrogenpolysiloxane (B2) differ in their structure, with the number of alkyl groups R attached to Si (R / Si) being 1 when the number of Si is taken as 1. For linear organohydrogenpolysiloxane (B1), the range is 1.8 to 2.1, while for branched organohydrogenpolysiloxane (B2), it is 0.8 to 1.7.

[0117] Furthermore, because branched organohydrogenpolysiloxane (B2) has a branched structure, the amount of residue when heated to 1000°C at a heating rate of 10°C / min under a nitrogen atmosphere is 5% or more. In contrast, because linear organohydrogenpolysiloxane (B1) is linear, the amount of residue after heating under the above conditions is almost zero.

[0118] Furthermore, a specific example of a branched organohydrogenpolysiloxane (B2) is one having a structure represented by the following formula (3).

[0119] [ka]

[0120] In formula (3), R 7 R is a substituted or unsubstituted alkyl group, aryl group, or a hydrocarbon group combining these, or a hydrogen atom, having 1 to 8 carbon atoms. Examples of alkyl groups having 1 to 8 carbon atoms include methyl, ethyl, and propyl groups, with methyl being preferred. An example of an aryl group having 1 to 8 carbon atoms is the phenyl group. 7 Examples of substituents include methyl groups.

[0121] Note that in equation (3), multiple R 7 These are independent of each other, and may be different from each other or the same.

[0122] Furthermore, in equation (3), "-O-Si≡" indicates that Si has a branched structure that extends in three dimensions.

[0123] Furthermore, branched organohydrogenpolysiloxane (B2) may be used alone or in combination of two or more types.

[0124] Furthermore, the amount of hydrogen atoms (hydride groups) directly bonded to Si in the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) is not particularly limited. However, in the silicone rubber-based curable composition, it is preferable that the total amount of hydride groups in the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) is 0.5 to 5 moles, and more preferably 1 to 3.5 moles, per mole of vinyl groups in the vinyl group-containing linear organohydrogenpolysiloxane (A1). This ensures the reliable formation of a crosslinking network between the linear organohydrogenpolysiloxane (B1) and the branched organohydrogenpolysiloxane (B2) and the vinyl group-containing linear organohydrogenpolysiloxane (A1).

[0125] <<Silica particles (C)>> The silicone rubber-based curable composition of this embodiment may optionally contain silica particles (C) as a non-conductive filler.

[0126] The silica particles (C) are not particularly limited, but for example, fumed silica, calcined silica, precipitated silica, etc., can be used. These may be used individually or in combination of two or more types.

[0127] Silica particles (C) have a specific surface area of, for example, 50-400 m² as determined by the BET method. 2 It is preferable that the amount is / g, and 100-400m 2 It is more preferable that the amount is / g. Furthermore, the average primary particle size of the silica particles (C) is preferably, for example, 1 to 100 nm, and more preferably about 5 to 20 nm.

[0128] By using silica particles (C) that fall within the specified range of specific surface area and average particle size, the hardness and mechanical strength of the resulting silicone rubber can be improved, particularly its tensile strength.

[0129] <<Silane coupling agent (D)>> The silicone rubber-based curable composition of this embodiment may contain a silane coupling agent (D). The silane coupling agent (D) may have a hydrolyzable group. The hydrolyzable group is hydrolyzed by water to a hydroxyl group, and this hydroxyl group undergoes a dehydration condensation reaction with the hydroxyl groups on the surface of the silica particles (C), thereby modifying the surface of the silica particles (C).

[0130] Furthermore, this silane coupling agent (D) may include a silane coupling agent having hydrophobic groups. As a result, these hydrophobic groups are imparted to the surface of the silica particles (C), which is expected to reduce the cohesive force of the silica particles (C) in the silicone rubber curable composition and, consequently, in the silicone rubber itself (reduced aggregation due to hydrogen bonding by silanol groups). This is expected to improve the dispersibility of the silica particles in the silicone rubber curable composition. This increases the interface between the silica particles and the rubber matrix, thereby increasing the reinforcing effect of the silica particles. Moreover, it is expected that the slipperiness of the silica particles within the matrix improves during deformation of the rubber matrix. As a result of the improved dispersibility and slipperiness of the silica particles (C), the mechanical strength of the silicone rubber due to the silica particles (C) (e.g., tensile strength and tear strength) is improved.

[0131] Furthermore, the silane coupling agent (D) may include a silane coupling agent having vinyl groups. This introduces vinyl groups to the surface of the silica particles (C). Therefore, during the curing of the silicone rubber-based curable composition, that is, when the vinyl groups of the vinyl group-containing organopolysiloxane (A) and the hydride groups of the organohydrogenpolysiloxane (B) undergo a hydrosilylation reaction to form a network (crosslinked structure), the vinyl groups of the silica particles (C) also participate in the hydrosilylation reaction with the hydride groups of the organohydrogenpolysiloxane (B), thus incorporating the silica particles (C) into the network. This makes it possible to achieve lower hardness and higher modulus in the formed silicone rubber.

[0132] As the silane coupling agent (D), a silane coupling agent having a hydrophobic group and a silane coupling agent having a vinyl group can be used in combination.

[0133] Examples of silane coupling agents (D) include those represented by the following formula (4).

[0134] Y n -Si-(X) 4-n ...(4) In formula (4) above, n represents an integer from 1 to 3. Y represents a functional group that has a hydrophobic group, a hydrophilic group, or a vinyl group, and when n is 1, it is a hydrophobic group, and when n is 2 or 3, at least one of them is a hydrophobic group. X represents a hydrolyzable group.

[0135] Hydrophobic groups are alkyl groups, aryl groups, or hydrocarbon groups having 1 to 6 carbon atoms, such as methyl groups, ethyl groups, propyl groups, and phenyl groups, with methyl groups being particularly preferred.

[0136] Furthermore, hydrophilic groups include, for example, hydroxyl groups, sulfonic acid groups, carboxyl groups, or carbonyl groups, with hydroxyl groups being particularly preferred. While hydrophilic groups may be included as functional groups, it is preferable that they are not included from the viewpoint of imparting hydrophobicity to the silane coupling agent (D).

[0137] Furthermore, hydrolyzable groups include alkoxy groups such as methoxy groups and ethoxy groups, chloro groups, or silazane groups, and among these, silazane groups are preferred due to their high reactivity with silica particles (C). Note that those having a silazane group as a hydrolyzable group are, due to their structural characteristics, (Y in formula (4) above. n It will have two -Si-) structures.

[0138] Specific examples of the silane coupling agent (D) represented by formula (4) above include, for example, alkoxysilanes such as methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, and decyltrimethoxysilane, which have a hydrophobic group as a functional group; chlorosilanes such as methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, and phenyltrichlorosilane; and hexamethyldisilazane, which have a hydrophobic group as a functional group. Examples of materials having a vinyl group include alkoxysilanes such as methacryloxypropyltriethoxysilane, methacryloxypropyltrimethoxysilane, methacryloxypropylmethyldiethoxysilane, methacryloxypropylmethyldimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, and vinylmethyldimethoxysilane; chlorosilanes such as vinyltrichlorosilane and vinylmethyldichlorosilane; and divinyltetramethyldisilazane. Among these, considering the above description, hexamethyldisilazane is particularly preferred as the material having a hydrophobic group, and divinyltetramethyldisilazane is preferred as the material having a vinyl group.

[0139] In this embodiment, the lower limit of the silane coupling agent (D) content is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, based on 100 parts by weight of the total amount of vinyl group-containing organopolysiloxane (A). The upper limit of the silane coupling agent (D) content is preferably 100% by mass or less, more preferably 80% by mass or less, and even more preferably 40% by mass or less, based on 100 parts by weight of the total amount of vinyl group-containing organopolysiloxane (A). By setting the content of the silane coupling agent (D) to above the lower limit, the silicone rubber can have appropriate adhesion to the flexible substrate 120, and when silica particles (C) are used, it can contribute to improving the overall mechanical strength of the silicone rubber. Furthermore, by setting the content of the silane coupling agent (D) to below the upper limit, the silicone rubber can have appropriate mechanical properties.

[0140] <<Platinum or platinum compound (E)>> The silicone rubber-based curable composition of this embodiment may contain platinum or a platinum compound (E). Platinum or platinum compound (E) is a catalytic component that acts as a catalyst during hardening. The amount of platinum or platinum compound (E) added is the catalytic amount.

[0141] As platinum or a platinum compound (E), known substances can be used, such as platinum black, platinum supported on silica or carbon black, chloroplatinic acid or an alcoholic solution of chloroplatinic acid, a complex salt of chloroplatinic acid and an olefin, or a complex salt of chloroplatinic acid and a vinylsiloxane.

[0142] Platinum or platinum compound (E) may be used alone or in combination of two or more types.

[0143] <<Water(F)>> Furthermore, the silicone rubber-based curable composition of this embodiment may also contain water (F) in addition to the above components (A) to (E).

[0144] Water (F) functions as a dispersion medium that disperses the various components contained in the silicone rubber curable composition, and also contributes to the reaction between silica particles (C) and the silane coupling agent (D). Therefore, the silica particles (C) and the silane coupling agent (D) can be more reliably linked to each other in the silicone rubber, resulting in uniform properties overall.

[0145] Furthermore, if water (F) is included, its content can be set as appropriate, but specifically, it is preferably in the range of 10 to 100 parts by weight, and more preferably in the range of 30 to 70 parts by weight, per 100 parts by weight of the silane coupling agent (D). This allows the reaction between the silane coupling agent (D) and the silica particles (C) to proceed more reliably.

[0146] (Other ingredients) Furthermore, the silicone rubber-based curable composition of this embodiment may further contain other components in addition to the components (A) to (F) described above. Examples of these other components include inorganic fillers other than silica particles (C), such as diatomaceous earth, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide, cerium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, glass wool, and mica; additives such as reaction inhibitors, dispersants, pigments, dyes, antistatic agents, antioxidants, flame retardants, and thermal conductivity enhancers.

[0147] In a silicone rubber-based curable composition, the proportion of each component is not particularly limited, but for example, it can be set as follows.

[0148] In this embodiment, the upper limit of the silica particle (C) content may be, for example, 60 parts by weight or less, preferably 50 parts by weight or less, and more preferably 40 parts by weight or less, per 100 parts by weight of the total amount of vinyl group-containing organopolysiloxane (A). This allows for a balance of mechanical strengths such as hardness and tensile strength. The lower limit of the silica particle (C) content is not particularly limited, but may be, for example, 10 parts by weight or more, per 100 parts by weight of the total amount of vinyl group-containing organopolysiloxane (A).

[0149] The silane coupling agent (D) is preferably present in an amount of 5 to 100 parts by weight, and more preferably 5 to 40 parts by weight, per 100 parts by weight of the vinyl group-containing organopolysiloxane (A). This ensures that the dispersibility of silica particles (C) in the silicone rubber-based curable composition is reliably improved.

[0150] The content of organohydrogenpolysiloxane (B) is preferably, for example, 0.5 parts by weight or more and 20 parts by weight or less, and more preferably 0.8 parts by weight or more and 15 parts by weight or less, per 100 parts by weight of the total amount of vinyl group-containing organopolysiloxane (A), silica particles (C), and silane coupling agent (D). A content of (B) within the above range may enable a more effective curing reaction.

[0151] The content of platinum or platinum compound (E) represents the catalytic amount and can be set as appropriate, but specifically, it is the amount such that the platinum group metal in this component is 0.01 to 1000 ppm by weight relative to the total amount of vinyl group-containing organopolysiloxane (A), silica particles (C), and silane coupling agent (D), preferably 0.1 to 500 ppm. By setting the content of platinum or platinum compound (E) to above the lower limit, the resulting silicone rubber composition can be sufficiently cured. By setting the content of platinum or platinum compound (E) to below the upper limit, the curing speed of the resulting silicone rubber composition can be improved.

[0152] Furthermore, if water (F) is included, its content can be set as appropriate, but specifically, it is preferably in the range of 10 to 100 parts by weight, and more preferably in the range of 30 to 70 parts by weight, per 100 parts by weight of the silane coupling agent (D). This allows the reaction between the silane coupling agent (D) and the silica particles (C) to proceed more reliably.

[0153] <Method for manufacturing silicone rubber> Next, the method for manufacturing the silicone rubber of this embodiment will be described. The method for producing silicone rubber according to this embodiment involves preparing a silicone rubber-based curable composition and curing this silicone rubber-based curable composition to obtain silicone rubber. The details are explained below.

[0154] First, the components of the silicone rubber curable composition are uniformly mixed using any kneading device to prepare the silicone rubber curable composition.

[0155] [1] For example, a predetermined amount of vinyl group-containing organopolysiloxane (A), silica particles (C), and a silane coupling agent (D) are weighed out, and then kneaded using any kneading device to obtain a kneaded product containing these components (A), (C), and (D).

[0156] It is preferable to obtain this compound by first kneading a vinyl group-containing organopolysiloxane (A) and a silane coupling agent (D), and then kneading (mixing) silica particles (C). This further improves the dispersibility of silica particles (C) in the vinyl group-containing organopolysiloxane (A).

[0157] Furthermore, when obtaining this mixture, water (F) may be added to the mixture of components (A), (C), and (D) as needed. This allows the reaction between the silane coupling agent (D) and the silica particles (C) to proceed more reliably.

[0158] Furthermore, it is preferable that the kneading of each component (A), (C), and (D) proceeds through a first step of heating at a first temperature and a second step of heating at a second temperature. This allows the surface of the silica particles (C) to be surface-treated with the coupling agent (D) in the first step, and ensures that by-products generated by the reaction between the silica particles (C) and the coupling agent (D) are reliably removed from the kneaded mixture in the second step. Subsequently, if necessary, component (A) may be added to the resulting kneaded mixture and kneaded further. This improves the compatibility of the components in the kneaded mixture.

[0159] The first temperature is preferably, for example, around 40 to 120°C, and more preferably, around 60 to 90°C. The second temperature is preferably, for example, around 130 to 210°C, and more preferably, around 160 to 180°C.

[0160] Furthermore, the atmosphere in the first step is preferably an inert atmosphere such as a nitrogen atmosphere, and the atmosphere in the second step is preferably a reduced pressure atmosphere.

[0161] Furthermore, the duration of the first step is preferably about 0.3 to 1.5 hours, and more preferably about 0.5 to 1.2 hours. The duration of the second step is preferably about 0.7 to 3.0 hours, and more preferably about 1.0 to 2.0 hours.

[0162] By setting the conditions for the first and second steps as described above, the aforementioned effects can be obtained more significantly.

[0163] [2] Next, predetermined amounts of organohydrogenpolysiloxane (B) and platinum or a platinum compound (E) are weighed out, and then, using any kneading apparatus, components (B) and (E) are kneaded into the mixture prepared in step [1] above to obtain a silicone rubber curable composition. The obtained silicone rubber curable composition may be a paste containing a solvent.

[0164] Furthermore, when kneading each of these components (B) and (E), it is preferable to first knead the kneaded product prepared in step [1] with the organohydrogenpolysiloxane (B), and the kneaded product prepared in step [1] with platinum or a platinum compound (E), and then knead each of these kneaded products. This ensures that each of the components (A) to (E) can be reliably dispersed in the silicone rubber-based curable composition without allowing the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B) to proceed.

[0165] The temperature at which components (B) and (E) are mixed is preferably, as the roll setting temperature, around 10 to 70°C, and more preferably around 25 to 30°C.

[0166] Furthermore, the mixing time is preferably, for example, 5 minutes to 1 hour, and more preferably 10 to 40 minutes.

[0167] In steps [1] and [2] described above, by keeping the temperature within the above range, the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B) can be more effectively prevented or suppressed. Furthermore, in steps [1] and [2] described above, by keeping the kneading time within the above range, each component (A) to (E) can be more reliably dispersed in the silicone rubber-based curable composition.

[0168] The kneading equipment used in each of the processes [1] and [2] is not particularly limited, but for example, a kneader, a two-roll mixer, a Banbury mixer (continuous kneader), a pressure kneader, etc., can be used.

[0169] Furthermore, in step [2], a reaction inhibitor such as 1-ethynylcyclohexanol may be added to the kneaded mixture. This makes it possible to more effectively prevent or suppress the reaction between the vinyl group-containing organopolysiloxane (A) and the organohydrogenpolysiloxane (B), even if the temperature of the kneaded mixture is set to a relatively high temperature.

[0170] [3] Next, silicone rubber is formed by curing the silicone rubber-based curable composition.

[0171] In this embodiment, the curing process of the silicone rubber-based curable resin composition is carried out, for example, by heating at 100 to 250°C for 1 to 30 minutes (primary curing), followed by post-baking at 200°C for 1 to 4 hours (secondary curing).

[0172] By going through the above process, silicone rubber consisting of a cured product of a silicone rubber-based curable resin composition is obtained.

[0173] [3] Next, an insulating paste can be obtained by dissolving the silicone rubber-based curable composition obtained in step [2] in a solvent. Furthermore, [3] Next, a conductive paste can be obtained by dissolving the silicone rubber-based curable composition obtained in step [2] in a solvent and adding a conductive filler.

[0174] (solvent) Conductive pastes and insulating pastes contain solvents. Various known solvents can be used as the solvent, but for example, high-boiling point solvents may be included. These may be used individually or in combination of two or more.

[0175] The lower limit of the boiling point of the high-boiling-point solvent is, for example, 100°C or higher, preferably 130°C or higher, and more preferably 150°C or higher. This improves the printing stability, such as in screen printing. On the other hand, the upper limit of the boiling point of the high-boiling-point solvent is not particularly limited, but may be, for example, 300°C or lower, 290°C or lower, or 280°C or lower. This suppresses excessive thermal history during wiring formation, thereby preventing damage to the substrate and maintaining the shape of the wiring formed with conductive paste in good condition.

[0176] Furthermore, the solvent can be appropriately selected from the viewpoint of its solubility and boiling point for the silicone rubber-based curable resin composition, but for example, it may include aliphatic hydrocarbons having 5 to 20 carbon atoms, preferably aliphatic hydrocarbons having 8 to 18 carbon atoms, and more preferably aliphatic hydrocarbons having 10 to 15 carbon atoms.

[0177] Examples of solvents include aliphatic hydrocarbons such as pentane, hexane, cyclohexane, heptane, methylcyclohexane, ethylcyclohexane, octane, decane, dodecane, and tetradecane; aromatic hydrocarbons such as benzene, toluene, ethylbenzene, xylene, mesitylene, trifluoromethylbenzene, and benzotrifluoride; and diethyl ether, diisopropyl ether, dibutyl ether, cyclopentyl methyl ether, cyclopentyl ethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, and diethylene glycol dimethyl ether. Examples include ethers such as chol monobutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol methyl-n-propyl ether, 1,4-dioxane, 1,3-dioxane, and tetrahydrofuran; haloalkanes such as dichloromethane, chloroform, 1,1-dichloroethane, 1,2-dichloroethane, 1,1,1-trichloroethane, and 1,1,2-trichloroethane; carboxylic acid amides such as N,N-dimethylformamide and N,N-dimethylacetamide; sulfoxides such as dimethyl sulfoxide and diethyl sulfoxide; and esters such as diethyl carbonate. These may be used individually or in combination of two or more. The solvent used here should be appropriately selected from among solvents that can uniformly dissolve or disperse the components of the conductive paste described above.

[0178] The above solvent has a polarity term (δ) in the Hansen solubility parameter. p The upper limit of ) is, for example, 10 MPa 1 / 2 The following is preferred: 7 MPa 1 / 2 The following, and more preferably 5.5 MPa 1 / 2 The following first solvent may be included. This improves the dispersibility and solubility of the silicone rubber-based curable resin composition in the paste. The above polarity term (δ) of this first solvent p The lower limit of ) is not particularly limited, but for example, 0 Pa 1 / 2 That's fine too.

[0179] The hydrogen bonding term (δ) of the Hansen solubility parameter in the first solvent described above. h The upper limit of ) is, for example, 20 MPa 1 / 2 The following, preferably 10 MPa 1 / 2 The following is more preferable: 7 MPa 1 / 2 The following is the result. This makes it possible to improve the dispersibility and solubility of the silicone rubber-based curable resin composition in the paste. The above hydrogen bonding term (δ) of this first solvent h The lower limit of ) is not particularly limited, but for example, 0 Pa 1 / 2 That's fine too.

[0180] Hansen's solubility parameter (HSP) is an index that represents the solubility of one substance, indicating how much of it dissolves in another substance. HSP represents solubility as a three-dimensional vector. This three-dimensional vector typically includes a dispersion term (δ). d ), polarity term (δ p ), hydrogen bond term (δ h It can be represented as follows. And if the vectors are similar, it can be judged that they have high solubility. The similarity of the vectors can be judged by the distance of the Hansen solubility parameters (HSP distance).

[0181] The Hansen solubility parameters (HSP values) used in this specification can be calculated using software called HSPiP (Hansen Solubility Parameters in Practice). HSPiP, developed by Hansen and Abbott, includes a function to calculate HSP distances and a database containing Hansen parameters for various resins and solvents or non-solvents. The solubility of each resin in pure solvents and mixed solvents of good and poor solvents is investigated, and the results are entered into HSPiP software to calculate D: dispersion term, P: polarity term, H: hydrogen bonding term, and R0: solubility sphere radius.

[0182] As the solvent in this embodiment, for example, one can be selected that has a small difference in HSP distance, polarity term, and hydrogen bonding term between the solvent and silicone rubber or the constituent units of silicone rubber.

[0183] The lower limit of viscosity of conductive paste and / or insulating paste measured at room temperature (25°C) with a shear rate of 20 [1 / s] is, for example, 1 Pa·s or more, preferably 5 Pa·s or more, and more preferably 10 Pa·s or more. This improves film formation and enhances shape retention even when forming thick films. On the other hand, the upper limit of viscosity of conductive paste and / or insulating paste at room temperature (25°C) is, for example, 100 Pa·s or less, preferably 90 Pa·s or less, and more preferably 80 Pa·s or less. This improves printability of the paste.

[0184] At room temperature of 25°C, the viscosity measured at a shear rate of 1 [1 / s] is defined as η1, and the viscosity measured at a shear rate of 5 [1 / s] is defined as η5. The thixotropy index is defined as the viscosity ratio (η1 / η5). In this case, the lower limit of the thixotropy of the conductive paste and / or insulating paste is, for example, 1.0 or higher, preferably 1.1 or higher, and more preferably 1.2 or higher. This allows the shape of the wiring obtained by the printing method to be stably maintained. On the other hand, the upper limit of the thixotropy of the conductive paste and / or insulating paste is, for example, 3.0 or lower, preferably 2.5 or lower, and more preferably 2.0 or lower. This improves the printability of the paste.

[0185] The content of the silicone rubber-based curable composition in the insulating paste is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, based on 100% by mass of the insulating paste. Furthermore, the content of the silicone rubber-based curable composition in the insulating paste is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less, based on 100% by mass of the insulating paste.

[0186] (Conductive filler) As the conductive filler, known conductive materials may be used, but metal powder (G) or conductive carbon material may also be used. The metals that make up the metal powder (G) are not particularly limited, but for example, it may include at least one of copper, silver, gold, nickel, tin, lead, zinc, bismuth, antimony, or alloys thereof, or two or more of these. Of these, it is preferable that the metal powder (G) contains silver or copper, i.e., silver powder or copper powder, due to its high conductivity and ease of availability. These metal powders (G) can also be used if they are coated with other metals.

[0187] Examples of conductive carbon materials include conductive carbon black, carbon nanotubes, and graphene.

[0188] In this embodiment, there are no restrictions on the shape of the metal powder (G), but conventionally used shapes such as dendritic, spherical, or flake-shaped can be used. Among these, flake-shaped metal powder (G) may also be used.

[0189] Furthermore, the particle size of the metal powder (G) is not limited, but for example, the average particle size D 50 The particle size is preferably 0.001 μm or larger, more preferably 0.01 μm or larger, and even more preferably 0.1 μm or larger. The particle size of the metal powder (G) is, for example, the average particle size D 50The particle size is preferably 1,000 μm or less, more preferably 100 μm or less, and even more preferably 20 μm or less. Average particle size D 50 By setting the range to this extent, the silicone rubber can exhibit appropriate conductivity. The particle size of the metal powder (G) can be defined, for example, by observing conductive paste or silicone rubber molded using conductive paste with a transmission electron microscope, performing image analysis, and then determining the average value of 200 arbitrarily selected metal powders.

[0190] The content of conductive filler in the conductive paste is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more, based on the total content of the conductive paste. Furthermore, the content of conductive filler in the conductive paste is preferably 85% by mass or less, more preferably 75% by mass or less, and even more preferably 65% ​​by mass or less, based on the total content of the conductive paste. By setting the conductive filler content above the lower limit, the silicone rubber can acquire appropriate conductivity. Furthermore, by setting the conductive filler content below the upper limit, the silicone rubber can acquire appropriate flexibility.

[0191] The content of the silicone rubber-based curable composition in the conductive paste is preferably 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, based on 100% by mass of the conductive paste. Furthermore, the content of the silicone rubber-based curable composition in the conductive paste is preferably 25% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, based on 100% by mass of the conductive paste. By setting the content of the silicone rubber-based curable composition to be above the lower limit, the silicone rubber can have appropriate flexibility. Furthermore, by setting the content of the silicone rubber-based curable composition to be below the upper limit, the mechanical strength of the silicone rubber can be improved.

[0192] The lower limit of the silica particle (C) content in the conductive paste can be, for example, 1% by mass or more, preferably 3% by mass or more, and more preferably 5% by mass or more, based on 100% by mass of the total amount of silica particles (C) and conductive filler. This can improve the mechanical strength of the silicone rubber. On the other hand, the upper limit of the silica particle (C) content in the conductive paste can be, for example, 20% by mass or less, preferably 15% by mass or less, and more preferably 10% by mass or less, based on 100% by mass of the total amount of silica particles (C) and conductive filler. This can balance the stretch-electrical properties and mechanical strength of the silicone rubber.

[0193] The conductive filler content in the conductive elastomer layer 20 may be 50% by mass or more and 90% by mass or less of 100% by mass of the conductive elastomer. The lower limit of the content of the conductive filler is, for example, 50% by mass or more, preferably 60% by mass or more, and more preferably 70% by mass or more, based on 100% by mass of the conductive elastomer. This enhances the stretchable electrical properties. On the other hand, the upper limit of the conductive filler content is, for example, 90% by mass or less, preferably 85% by mass or less, of 100% by mass of the conductive elastomer. This suppresses a decrease in rubber properties such as elasticity.

[0194] Although embodiments of the present invention have been described above, these are merely examples, and various other configurations can be adopted. Furthermore, the present invention is not limited to the embodiments described above, and modifications, improvements, etc., within the scope that can achieve the objectives of the present invention are included in the present invention. [Examples]

[0195] The present invention will be described in detail below with reference to examples, but the present invention is not limited in any way to the descriptions of these examples.

[0196] The raw material components shown in Table 1 are listed below. (A1-1): First vinyl group-containing linear organopolysiloxane: Vinyl group-containing dimethylpolysiloxane synthesized by the following synthesis scheme 1 (structure represented by formula (1-1) above) (A1-2): Second vinyl group-containing linear organopolysiloxane: Vinyl group-containing dimethylpolysiloxane synthesized by the following synthesis scheme 2 (with the structure represented by formula (1-1) above) 1 and R 2 (A structure in which the vinyl group is)

[0197] (Organohydrogenpolysiloxane (B)) (B-1): Organohydrogenpolysiloxane: Momentive Corporation, "TC-25D"

[0198] (Silica particles (C)) (C): Silica nanoparticles (particle size 7nm, specific surface area 300m²) 2 / g), manufactured by Nippon Aerosil Co., Ltd., "AEROSIL300"

[0199] (Silane coupling agent (D)) (D-1): Hexamethyldisilazane (HMDZ), manufactured by Gelest, "HEXAMETHYLDISILAZANE(SIH6110.1)" (D-2) Divinyltetramethyldisilazane, manufactured by Gelest, "1,3-DIVINYLTETRAMETHYLDISILAZANE(SID4612.0)"

[0200] (Platinum or platinum compound (E)) (E-1): Platinum compound (manufactured by Momentive, trade name "TC-25A")

[0201] (Water(F)) (F):Pure water

[0202] (Metal powder (G)) (G1): Silver powder, manufactured by Tokuriki Chemical Research Institute, product name "TC-101", median diameter d 50 : 8.0 μm, aspect ratio 16.4, average major diameter 4.6 μm

[0203] (Synthesis of vinyl group-containing organopolysiloxane (A)) [Synthesis Scheme 1: Synthesis of the first vinyl group-containing linear organopolysiloxane (A1-1)] A first vinyl group-containing linear organopolysiloxane (A1-1) was synthesized according to the following formula (5). Specifically, 74.7 g (252 mmol) of octamethylcyclotetrasiloxane and 0.1 g of potassium silicate were placed in a 300 mL separable flask equipped with a condenser and stirring blades, which had been purged with Ar gas. The mixture was then heated and stirred at 120°C for 30 minutes. An increase in viscosity was observed during this process. The temperature was then raised to 155°C, and stirring was continued for 3 hours. After 3 hours, 0.1 g (0.6 mmol) of 1,3-divinyltetramethyldisiloxane was added, and stirring was continued at 155°C for another 4 hours. Furthermore, after 4 hours, the mixture was diluted with 250 mL of toluene and washed three times with water. The organic layer after washing was reprecipitated and purified by washing several times with 1.5 L of methanol to separate the oligomer and polymer. The obtained polymer was dried under reduced pressure at 60°C overnight to obtain the first vinyl group-containing linear organopolysiloxane (A1-1) (Mn = 2.2 × 10⁻⁶). 5 Mw = 4.8 × 10 5 Furthermore, the vinyl group content, calculated by 1H-NMR spectroscopy, was 0.04 mol%.

[0204] [ka]

[0205] [Synthesis Scheme 2: Synthesis of the second vinyl group-containing linear organopolysiloxane (A1-2)] In the synthesis step of (A1-1) described above, 0.86 g (2.5 mmol) of 2,4,6,8-tetramethyl2,4,6,8-tetravinylcyclotetrasiloxane was used in addition to 74.7 g (252 mmol) of octamethylcyclotetrasiloxane. Except for this difference, the synthesis step was carried out in the same manner as in (A1-1), and a second vinyl group-containing linear organopolysiloxane (A1-2) was synthesized as shown in formula (6) below (Mn = 2.3 × 10⁻¹⁵). 5 Mw = 5.0 × 10 5 Furthermore, the vinyl group content, calculated by 1H-NMR spectroscopy, was 0.93 mol%.

[0206] [ka]

[0207] (Preparation of silicone rubber-based curable compositions) The silicone rubber-based curable composition for Sample 1 was prepared according to the following procedure. First, a mixture of 90% vinyl group-containing organopolysiloxane (A), silane coupling agent (D), and water (F) was pre-kneaded in the proportions shown in Table 1 below. Then, silica particles (C) were added to the mixture and kneaded further to obtain a compound (silicone rubber compound). Here, the mixing after the addition of silica particles (C) was carried out in two steps: the first step of mixing under a nitrogen atmosphere at 60-90°C for 1 hour for the coupling reaction, and the second step of mixing under a reduced pressure atmosphere at 160-180°C for 2 hours to remove the by-product (ammonia). After that, it was cooled, and the remaining 10% vinyl group-containing organopolysiloxane (A) was added in two parts and mixed for 20 minutes. Next, organohydrogenpolysiloxane (B), platinum, or a platinum compound (E) were added to 100 parts by weight of the resulting mixture (silicone rubber compound) in the proportions shown in Table 2 below, and the mixture was kneaded with a roll to obtain a silicone rubber-based curable composition.

[0208] (Preparation of conductive paste) The obtained 15.3 parts by weight of the silicone rubber-based curable composition of Sample 1 was immersed in 34.8 parts by weight of decane (solvent), followed by stirring with a rotation-revolution mixer. After adding 65.2 parts by weight of metal powder (G1), it was kneaded with a rotation-revolution mixer to obtain a conductive paste with a total content of the silicone rubber-based curable composition and the metal powder (G1) of 69.8% by weight.

[0209] Using the above conductive paste, it was dried at 140 °C for 20 minutes and cured at 180 °C for 2 hours to form a sheet-like test piece with a thickness of 0.05 mm. Using the above test piece, the elongation at break was measured in accordance with JIS K6251 (2004). The elongation at break was calculated by [distance of movement between chucks (mm)] ÷ [initial distance between chucks (60 mm)] × 100. The elongation at break of the sheet-like test piece was 180%. Also, using the above test piece, the breaking strength was measured in accordance with JIS K6251 (2004). The breaking strength of the sheet-like test piece was 2.3 MPa.

[0210]

Table 1

[0211] <Manufacture of sheet electrode> On the plane of a SUS substrate, a flexible substrate (woven fabric made of polyester, basis weight 130 g / m 2 ) with a size of 7 cm × 7 cm × 0.4 mm t was placed. Subsequently, a mask (made of polyethylene terephthalate) with a thickness of 125 μm and having one opening of 5 cm × 5 cm was placed on the surface of the flexible substrate. Subsequently, the above conductive paste was applied to the opening of the mask, and squeegee printing was performed multiple times using a glass plate in the printing direction perpendicular to the fiber mesh. Subsequently, the mask was removed, and the printed conductive paste 1 was dried at 140 °C for 20 minutes and cured at 180 °C for 2 hours to form a conductive elastomer layer on the flexible substrate. Thereafter, through-holes penetrating the flexible base material and the conductive elastomer layer were formed using a blade under the conditions shown in Table 2 (shape of the through-holes, maximum width D1, number, minimum pitch D2), and a flexible sheet electrode was fabricated. However, in the production of the flexible sheet electrode of Comparative Example 1, formation of through-holes was not carried out.

[0212] ​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​In each of the obtained sheet electrodes, an external connector (a metal male snap button) was attached to the other side of the flexible substrate opposite to the side on which the conductive elastomer layer was formed, and the external connector and the conductive elastomer layer were electrically connected to obtain a wearable bioelectrode. Three wearable bioelectrodes were prepared, and the external connection points of each of the three wearable bioelectrodes were connected to a BITalino (manufactured by Plux) via electrode cables with connectors (female snap buttons) and ECG sensors (manufactured by Plux), thereby creating an electrocardiogram measurement device (biosensor). Flexible sheet electrodes, each attached to one side of three wearable bioelectrodes, were placed directly on the subject's skin, and the subject's electrocardiogram was measured using a three-lead method (measurement point, reference, and body ground). The results above confirm that electrocardiogram waveforms can be monitored by using wearable bioelectrodes equipped with sheet electrodes as described in each embodiment.

[0217] The sheet electrodes of Examples 1 to 5 showed superior attachment performance compared to Comparative Example 1. Furthermore, the sheet electrodes of Examples 1 to 5 showed excellent measurement stability. Such sheet electrodes can be suitably used as bioelectrodes. [Explanation of symbols]

[0218] 10 Flexible base material 20 Conductive elastomer layer 30 Through hole P 50 Through hole Q 100 sheet electrodes

Claims

1. A sheet-like conductive elastomer layer, A sheet electrode comprising a plurality of through holes P formed in the conductive elastomer layer.

2. A sheet electrode according to claim 1, The flexible substrate comprises a conductive elastomer layer that holds the conductive elastomer layer on at least one surface. A sheet electrode having a structure in which at least one of the multiple through holes P penetrates the flexible substrate.

3. Flexible substrate and A sheet-like conductive elastomer layer is held on at least one surface of the flexible substrate, A sheet electrode comprising a plurality of through-holes Q that penetrate the flexible substrate but do not penetrate the conductive elastomer layer.

4. A sheet electrode according to claim 1 or 2, A sheet electrode in which, when viewed from the vertical direction of the surface of the conductive elastomer layer, the maximum width D1 of the through hole P is 0.1 mm or more and 10 mm or less.

5. A sheet electrode according to any one of claims 1 to 3, A sheet electrode having a conductive elastomer layer with a thickness of 0.005 mm or more and 2 mm or less.

6. A sheet electrode according to claim 1 or 2, When the maximum width (mm) of the through-hole P as viewed from the vertical direction on the surface of the conductive elastomer layer is D1, and the thickness (mm) of the conductive elastomer layer is H, A sheet electrode in which D1 / H is between 0.05 and 2000.

7. A sheet electrode according to claim 1 or 2, A sheet electrode in which the minimum pitch D2 between the centers of the multiple through holes P is 0.1 mm or more and 10 mm or less.

8. A sheet electrode according to claim 1 or 2, A sheet electrode in which, when viewed from the vertical direction of the surface of the conductive elastomer layer, the shape of the through-hole P is circular, elliptical, or a polygon without corners.

9. A sheet electrode according to claim 1 or 2, A sheet electrode in which, when viewed from the vertical direction of the surface of the conductive elastomer layer, the area surrounded by the outer edge of the sheet electrode is A1, the area surrounded by the outer edge of the conductive elastomer layer is A2 (however, including the region in which the through-holes P are formed), and the total area of ​​the multiple through-holes P is A3, such that 10% ≤ [(A2 - A3) / A1] × 100 < 100%.

10. A sheet electrode according to claim 1 or 2, The number of through holes P in the conductive elastomer layer is 0.1 holes / cm². ２ More than 2500 pieces / cm ２ The sheet electrode is as follows.

11. A sheet electrode according to claim 1 or 2, A sheet electrode in which the minimum distance D3 between the ends of the multiple through holes P and the ends of the conductive elastomer layer is 0.1 mm or more.

12. A sheet electrode according to any one of claims 1 to 3, A sheet electrode having a tensile strength of 0.5 MPa or more in the conductive elastomer layer.

13. A sheet electrode according to any one of claims 1 to 3, A sheet electrode having a break elongation of 10% or more in the conductive elastomer layer.

14. A sheet electrode according to any one of claims 1 to 3, A sheet electrode wherein the conductive filler content in the conductive elastomer layer is 50% by mass or more and 90% by mass or less.

15. A sheet electrode according to any one of claims 1 to 3, A sheet electrode in which the conductive elastomer layer includes conductive silicone rubber.

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