Electrodes for high frequency medical devices and medical devices

Abstract

This conductive adhesion preventing film (1B) has a silicone resin (4) and at least one type of fillers (5) having conductivity, the fillers (5) are joined to each other, and the fillers (5) are joined to at least one side of an electrode substrate (1A) disposed on the surface of a treatment section. The fillers (5) have an angular shape, have an average particle diameter of 3 μm or more, are smaller than the film thickness of the conductive adhesion preventing film (1B), and have a true density of 11g / cm3 or less. In the fillers (5), a core composed of aluminum, copper, a ceramic such as alumina, silica, glass, and calcium titanate fiber, a resin such as acryl, hollow particles, and rubber is coated with silver.

Description

[Technical field]

[0001] The present invention relates to an electrode for a high-frequency medical device and a medical device. [Background technology]

[0002] As a medical device, a device that applies a high-frequency voltage to biological tissue is known. For example, a high-frequency treatment tool, which is an example of such a medical device, applies a high-frequency voltage to biological tissue to incise, coagulate, or cauterize the biological tissue. In order for such medical devices to fulfill their function of treating biological tissue, the surface area that comes into contact with the biological tissue must be electrically conductive. However, metals with good electrical conductivity tend to adhere to biological tissue, which can reduce visibility and operability during use of the high-frequency treatment device.

[0003] For example, Patent Document 1 describes an electrode that prevents deterioration of visibility and operability during use by preventing adhesion of biological tissue to the conductive part. Patent Document 1 describes an electrode in which the surface of the conductive part is coated with a thin film of polydimethylsiloxane as a technology for preventing adhesion of biological tissue. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] US Patent Publication No. 2019 / 0090934 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the above-mentioned conventional techniques have the following problems. According to the technology described in Patent Document 1, the polydimethylsiloxane thin film that constitutes the electrode has a methyl group in the side chain, so it is difficult to form a hydrogen bond with the electrode base material and is easily peeled off. In other words, biological tissue sticks to the peeled part of the thin film, and repeated use reduces the adhesion prevention property that prevents adhesion of biological tissue, so it is required to maintain this adhesion prevention property.

[0006] Here, in order to ensure the electrical conductivity of the thin film for preventing adhesion as a high-frequency electrode, a technique is known in which a conductive filler is mixed into a silicone resin. The silicone resin is responsible for preventing adhesion and ensuring adhesion to the electrode base material. In this case, in order to ensure sufficient electrical conductivity, it is necessary to increase the ratio of the conductive filler to the silicone resin. However, if the ratio of the conductive filler is increased too much, the anti-adhesive performance is reduced, and the adhesion to the electrode base material is also reduced, causing peeling, and there is a problem that the peeled part is significantly stuck to the living tissue. Therefore, there is a demand for a high-frequency electrode made of a thin film that has sufficient conductivity and anti-sticking properties even when the amount of conductive filler is reduced.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an electrode for high-frequency medical equipment and a medical equipment that can maintain good conductivity without reducing the anti-adhesive performance that makes it difficult for biological tissue to adhere, even when repeatedly used to treat biological tissue. [Means for solving the problem]

[0008] In order to solve the above problems, a high-frequency medical device electrode according to a first aspect of the present invention is an electrode for high-frequency medical devices in which a coating film is formed on at least a part of the surface of a treatment section for a medical device, the coating film being a conductive anti-adhesion film having a silicone resin and at least one type of filler having electrical conductivity, the fillers being fusion-bonded to each other and / or to an electrode base material located on the surface of the treatment section to form a conductive path, the electrode surface of the coating film having an exposed portion where the filler is exposed from the silicone resin and a smooth surface made of silicone resin excluding the exposed portion, the area of ​​the exposed portion in a plan view being smaller than the surface area of ​​the silicone resin. Ku , The filler is composed of two or more types of fillers having different particle sizes, and the ratio of fillers having small particle sizes is high in the vicinity of the electrode substrate. .

[0009] In the high-frequency medical device electrode, the filler preferably has a shape having corners.

[0011] In the above-mentioned high-frequency medical device electrode, the filler may be a core made of aluminum, copper, alumina, silica, glass, ceramics such as calcium titanate fiber, resins such as acrylic, hollow particles, or rubber, which is coated with a material having a volume resistivity of 9 Ω cm or less, such as silver or gold.

[0013] A medical device according to a second aspect of the present invention comprises the above-mentioned electrode for high-frequency medical device. Effect of the Invention

[0014] The electrodes for high-frequency medical devices and medical devices of the present invention have the advantage of being able to maintain good electrical conductivity without compromising the anti-adhesive performance that makes it difficult for biological tissue to adhere, even when used repeatedly to treat biological tissue. [Brief description of the drawings]

[0015] [Figure 1] FIG. 1 is a schematic configuration diagram showing an example of a medical device according to an embodiment of the present invention. [Diagram 2] 2 is a cross-sectional view taken along the line AA in FIG. [Diagram 3]FIG. 1 is a schematic cross-sectional view of an electrode for a high-frequency medical device according to an embodiment of the present invention. [Figure 4] FIG. 2 is a schematic diagram showing the structure of a conductive filler of an electrode for a high-frequency medical device. [Diagram 5] FIG. 2 is a schematic cross-sectional view of a high-frequency medical device electrode according to a first modified example of an embodiment of the present invention. [Figure 6] FIG. 11 is a schematic cross-sectional view of a high-frequency medical device electrode according to a second modified example of an embodiment of the present invention. [Figure 7] FIG. 11 is a schematic cross-sectional view of a high-frequency medical device electrode according to a third modified example of an embodiment of the present invention. [Figure 8] FIG. 11 is a schematic cross-sectional view of a high-frequency medical device electrode according to a fourth modified example of the embodiment of the present invention. [Figure 9A] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to an embodiment of the present invention. [Figure 9B] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to an embodiment of the present invention. [Figure 9C] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to a comparative example. [Figure 9D] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to a comparative example. [Figure 9E] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to a comparative example. [Figure 9F] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to a comparative example. [Figure 9G] FIG. 2 is a diagram showing a schematic diagram of a conductive filler according to a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, a high-frequency medical device electrode and a medical device according to an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a schematic diagram showing an example of a medical device according to an embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line AA in Fig. 1. Fig. 3 is a schematic cross-sectional view of an electrode for a high-frequency medical device according to an embodiment of the present invention. Since each drawing is a schematic diagram, the shapes and dimensions are exaggerated (the same applies to the following drawings).

[0017] 1 is an example of a medical instrument according to the present embodiment. The high-frequency device 10 is a bipolar medical treatment tool that coagulates (stops bleeding) or cauterizes biological tissue by applying a high-frequency voltage between opposing electrodes. The high-frequency device 10 comprises a handle-shaped operating section 20 for the surgeon to hold in his hand, an electrode section 1 provided at the tip of a shaft 21 protruding from the tip of the operating section 20, and a power supply unit 40 electrically connected to the electrode section 1 via the operating section 20.

[0018] The electrode section 1 is provided with a pair of electrode sections 11A and 11B. A second electrode section (here, reference numeral 11B) is provided so as to be capable of opening and closing relative to a first electrode section (here, reference numeral 11A). The first electrode section 11A is a fixed electrode, and the second electrode section 11B is a movable substrate.

[0019] The operation unit 20 includes an operation unit main body 22, a grip portion 23, and an operation handle 24. Inside the operation unit main body 22, the operation handle 24 is connected to a wire or rod that is inserted through the shaft 21 and connected to the second electrode unit 11B. Displacement of the operation handle 24 based on the operation of the surgeon is transmitted to the second electrode unit 11B through the wire or rod to which the operation handle 24 is connected. As a result, the second electrode unit 11B is displaced relative to the first electrode unit 11A in accordance with the movement of the operation handle 24.

[0020] One end of a cable 25 extending from a power supply unit 40 is connected to the base end side of the operation unit 20. The other end of the cable 25 is connected to the power supply unit 40. An electric signal line and an electric signal line for applying high frequency power to the pair of electrodes 11A, 11B are inserted inside the cable 25.

[0021] The power supply unit 40 includes a control unit 41 and a high-frequency driving unit 42 . The control unit 41 controls each unit of the high-frequency device 10. For example, the control unit 41 controls the operation of the high-frequency driving unit 42 in response to an operation input from the operation handle 24. The high-frequency driving unit 42 supplies high-frequency current to the electrode unit 1 in response to a control signal sent from the control unit 41. High-frequency power is applied to the electrode unit 1 constituting a bipolar electrode through an electric signal line (not shown) inserted in the cable 25.

[0022] The electrode section 1 applies a high-frequency voltage while gripping a biological tissue (e.g., a blood vessel) to be treated. The outer shape of each of the first electrode section 11A and the second electrode section 11B constituting the electrode section 1 is, as a whole, a straight or curved rod or plate shape.

[0023] 2, each of the pair of electrode parts 11A and 11B includes a metal electrode base material 1A and a conductive anti-adhesion film 1B (coating film) of this embodiment. The conductive anti-adhesion film 1B is coated on the opposing surfaces of the electrode base material 1A in the opposing electrode parts 11A and 11B.

[0024] The material of the electrode substrate 1A may be an appropriate metallic material having electrical conductivity, such as a metal or an alloy, etc. For example, the material of the electrode substrate 1A may be an aluminum alloy, stainless steel, copper, etc.

[0025] 2, the conductive anti-adhesive film 1B is a film provided so as to cover the electrode substrate surface 1a. The outer surface of the conductive anti-adhesive film 1B constitutes the electrode surface 1b of the electrode part 1.

[0026] 3, the conductive anti-adhesive film 1B includes a silicone resin 4 as a base material, and one type of conductive filler 5 dispersed in the silicone resin 4. In the conductive anti-adhesive film 1B, the fillers 5 are bonded together, and at least one of the fillers 5 and the electrode base material 1A located on the surface of the treatment area is bonded at points or surfaces by thermal fusion. That is, in the manufacturing process, energy is applied from the outside to the conductive adhesion prevention film 1B containing the filler 5 to heat the filler 5 and soften or melt at least a part of it, making the filler 5 deformable. The deformable filler 5 bonds with other fillers 5 at points or faces, or bonds with the electrode base material 1A at points or faces. The bonding at faces is a concept that includes integration by melting. This bonding at faces by fusion is maintained even after the filler 5 cools and hardens. This bonding at faces by fusion is hereinafter referred to as fusion bonding. A part of the filler 5 (exposed part 5b) is exposed to the outside from the silicone resin 4. The surface 4a of the silicone resin 4 and the exposed part 5b of the filler 5 exposed from the surface 4a of the silicone resin 4 constitute the electrode surface 1b. A part of the filler 5 (bonding part 5c) is bonded to the electrode base material 1A at a face by fusion. Note that when the filler 5 is not exposed and the film thickness between the filler 5 and the surface 4a of the silicone resin 4 is 1 μm or less, the adhesion prevention performance is further improved. Furthermore, when the film thickness is 100 nm or less, the treatment performance is further improved. The thickness of the conductive anti-adhesive film 1B can be set appropriately so as to obtain the strength required for the high-frequency device 10. For example, the thickness of the conductive anti-adhesive film 1B may be about 5 μm.

[0027] The silicone resin 4 may be a non-conductive material that is unlikely to adhere to biological tissue and has heat resistance sufficient to withstand heat generated during use of the high-frequency device 10. The silicone resin 4 may have a lower thermal conductivity than the filler 5 described below. In this case, the silicone resin 4 also has excellent heat insulating properties.

[0028] 3 is a schematic diagram of individual filler particles 5 fused together at fused portions 51. As shown in FIG. 4, each filler particle 5 is formed in a flake shape having at least one corner 5a. The filler particles 5 have an average particle size of 3 μm or more, which is smaller than the film thickness of the conductive adhesion prevention film 1B (for example, about 5 μm as described above), and a true density of 11 g / cm. 3It is more preferable that the filler 5 is equal to or smaller than the above. The filler 5 may be of a generally polygonal shape with the apex chamfered as in the example of FIG. 4, or may be of a generally rectangular, elongated shape as shown in the first modified example described later. The filler 5 of such a shape only needs to have a maximum diameter that satisfies the above-mentioned numerical range of the average particle size. The corners 5a of the filler 5 are easily melted by heat, and are easily fused to other fillers 5 in the vicinity. The average particle size and true density of the filler 5 are measured by processing a cross section of the conductive adhesion prevention film 1B and observing the filler 5 on the processed surface with an electron microscope. Ion milling may be used for processing the cross section. If the filler 5 is formed in a cornerless flake or spherical shape, the filler particles 5 do not thermally fuse together due to melting of the corners, so the continuity between the filler particles 5 due to fusion is low, conductive paths are difficult to form, and sufficient conductivity is not obtained.

[0029] The material of the filler 5 may be a metal. The electric resistivity of the metal used for the filler 5 may be, for example, 9Ω or less. Examples of metals with low electric resistivity include silver, nickel, copper, and gold. In particular, nickel and copper are more preferable because they are less expensive than silver, gold, and the like. However, the filler 5 is not limited to metals as long as it is conductive.

[0030] For example, a composite material in which a core made of aluminum, copper, alumina, silica, glass, ceramics such as calcium titanate fiber, resins such as acrylic, hollow particles, rubber, or the like is coated with a conductive metal such as silver may be used as the filler 5. In this case, it is more preferable that the metal coats the entire surface of the non-conductive material. In short, it is sufficient that the coating material can fuse the fillers 5 together by heat. Examples of the non-conductive material include inorganic materials such as glass, silica, alumina, zirconia, etc. As the non-conductive material in the composite material, a resin material having heat resistance capable of withstanding heat generated during use of the high-frequency device 10 may be used. The non-conductive material may have a hollow structure. When the non-conductive material has a hollow structure, the heat insulating properties of the filler 5 can be improved.

[0031] Examples of the metal in the composite material include silver, nickel, copper, and gold. Methods that can be used to coat the surface of the core with these metals include electroless plating, PVD (Physical Vapor Deposition), and CVD (Chemical Vapor Deposition). Examples of PVD include sputtering and deposition. When the filler 5 is formed of a composite material of a non-conductive material and a metal, the amount of metal used, which is more expensive than the non-conductive material, is reduced, and the component cost of the filler 5 is reduced compared to when the filler 5 is formed only of a metal. For example, a non-metallic conductor may be used as the filler 5. As the non-metallic conductor, carbon fibers, carbon nanotubes, etc. may be used.

[0032] The amount of the filler 5 added to the conductive adhesion preventive film 1B is preferably in the range of, for example, 60 wt % to 90 wt %. If the amount of filler 5 added is less than 60 wt%, the probability of the filler 5 fusing together in the conductive adhesion prevention film 1B decreases, so that the continuity due to fusing between the filler 5 decreases and the conductive paths decrease. In this case, good conductivity cannot be obtained in the conductive adhesion prevention film 1B. If the amount of filler 5 added exceeds 90 wt %, the area of ​​the filler 5 exposed on the electrode surface 1b becomes too large, and the distance between the exposed portions 5b becomes too narrow. As a result, the surface area of ​​the silicone resin 4, which has high biological tissue adhesion preventing performance, decreases on the electrode surface 1b, and the biological tissue adhesion preventing performance on the electrode surface 1b deteriorates.

[0033] The average particle size of the filler 5 is preferably 2 μm or more. If the length of the filler 5 is less than 2 μm, the probability that one filler 5 will fuse with another filler 5 in the length direction decreases. In this case, good conductivity cannot be obtained in the conductive adhesion prevention film 1B.

[0034] The conductive anti-adhesion film 1B having the above-described configuration may be formed, for example, by painting. In this case, first, a paint is prepared by dispersing the silicone resin 4 and the filler 5 in an appropriate dispersion liquid such as water. Then, the paint is applied to the electrode substrate surface 1a of the electrode substrate 1A by an appropriate painting means. The painting means is not particularly limited. Examples of the coating method include spray coating, dip coating, spin coating, screen printing, inkjet printing, flexographic printing, gravure printing, pad printing, hot stamping, etc. Spray coating and dip coating are particularly suitable as coating methods for forming the conductive adhesion preventive film 1B on the medical device, since they can be easily applied even to objects having complex shapes.

[0035] When the paint is applied to the electrode substrate surface 1a of the electrode substrate 1A, the filler 5 moves within the paint until the paint dries. At this time, the filler 5 within the paint is oriented along the electrode substrate surface 1a, which is the coated surface, due to gravity or an external force acting from the coating means during coating. That is, the filler 5 within the paint is mixed with the silicone resin 4 and entangled with other fillers 5, and tends to assume a posture parallel to the electrode substrate surface 1a or intersecting at a shallow angle. After the coating film is formed on the electrode substrate surface 1a, the dispersion liquid is evaporated by drying, resulting in the formation of a conductive adhesion preventive film 1B in which the filler 5 is dispersed in the silicone resin 4.

[0036] Next, the operation of the high-frequency device 10 having such a configuration will be described. Treatment using the high-frequency device 10 is performed, for example, with an affected area of ​​a patient being grasped by the electrode portions 11A and 11B and a high-frequency voltage being applied by the high-frequency power source 3 to the electrode portions 11A and 11B. The electrode part 1 is covered with a conductive anti-adhesive film 1B. Filler particles 5 are dispersed inside the conductive anti-adhesive film 1B. A large number of fillers 5 are dispersed inside the conductive anti-adhesive film 1B in a state of being fused to each other. Therefore, most of the fillers 5 are directly or indirectly conductive to the electrode substrate surface 1a. That is, inside the conductive anti-adhesive film 1B, a large number of conductive paths are formed by the fillers 5 that are bonded to each other by fusion, which connect the ends (exposed parts 5b) of the fillers 5 that form part of the electrode surface 1b to the electrode substrate surface 1a. The electrode surface 1b of the conductive adhesion prevention film 1B is composed of a smooth surface made of the silicone resin 4, except for the filler 5 exposed from the silicone resin 4. The area of ​​the exposed part of the filler 5 in a plan view is much smaller than the surface area of ​​the silicone resin 4. The amount of protrusion of the exposed part of the filler 5 from the surface of the silicone resin 4 is also very small.

[0037] When a high-frequency voltage is applied between the electrode parts 11A and 11B, a high-frequency current is generated through the conductive anti-adhesive film 1B. The conductive part at the contact part between the electrode surface 1b of the electrode part 1 and the living tissue is an exposed part of the filler 5, and therefore has an extremely small area compared to the area of ​​the electrode part 1. Therefore, at the contact part between the electrode part 1 and the living tissue, a current with a high current density flows from the filler 5 exposed on the electrode surface 1b to the living tissue, generating Joule heat. This causes the moisture in the living tissue of the subject to evaporate rapidly, and the living tissue is cauterized, enabling hemostasis and coagulation. When the necessary treatment is completed, the surgeon separates the electrode portion 1 from the subject. At this time, most of the electrode surface 1b in contact with the biological tissue is not the filler 5 to which biological tissue easily adheres, but the silicone resin 4 to which biological tissue does not easily adhere. Therefore, when the electrode portion 1 is separated, the biological tissue easily peels off from the electrode surface 1b. The electrode surface 1b is a rough surface with minute protrusions formed by the exposed portions of the filler 5. For this reason, compared to when the electrode surface 1b is composed only of a smooth surface such as the surface of the silicone resin 4, discharge is more likely to occur from the protrusions, improving treatability, but reducing adhesion prevention. The ideal state in terms of both treatability and adhesion prevention is when the protrusions formed by the filler 5 are covered with a thin silicone resin film. Thus, in the high-frequency device 10, biological tissue hardly adheres to the electrode surface 1b.

[0038] If biological tissue that has not been completely removed adheres to the electrode surface 1b, the electrical conductivity at the adhered area decreases, and electrical energy is not sufficiently released from the adhered area, resulting in a decrease in treatment performance at the adhered area of ​​the biological tissue. However, as described above, since almost no biological tissue adheres to the electrode surface 1b of the electrode portion 1, the high-frequency device 10 can prevent a decrease in treatment performance during treatment. Furthermore, the durability of the electrode portion 1 is ensured even if the electrode portion 1 is used repeatedly.

[0039] In this embodiment, the filler 5 in the conductive anti-adhesive film 1B has conductivity and a corner 5a, and the fillers 5, 5 are bonded to each other and to the electrode substrate 1A. That is, the conductive anti-adhesive film 1B of the silicone resin 4 containing the filler 5 is formed on the surface of the electrode substrate 1A, and by heating the conductive anti-adhesive film 1B, the filler 5 melts and deforms, and the adjacent fillers 5 are fused to each other and to the electrode substrate 1A, forming a conductive path, thereby improving the conductivity of the conductive anti-adhesive film 1B. In this way, when the fillers 5 are fused to each other, the bonding area between them becomes larger and a thick conductive path is formed, so that the amount of filler 5 added can be reduced, and sufficient conductivity can be obtained even with a small amount of filler 5 added. In this manner, in the conductive anti-adhesion film 1B of this embodiment, by containing an appropriate amount of filler 5 in the silicone resin 4, it is possible to achieve both electrical conductivity and anti-adhesion performance against biological tissue in the conductive anti-adhesion film 1B.

[0040] In the embodiment, the average particle size of the filler 5 is 3 μm or more and the true density is 11 g / cm 3 By setting the content below, the fusion area of ​​the filler 5 with the electrode base material 1A can be increased, and good electrical conductivity can be obtained. Furthermore, since the filler 5 forms a network-like bond within the silicone resin 4, the silicone resin 4 can be held with a high force.

[0041] As described above, according to the high-frequency device 10 of the present embodiment, since the surface of the electrode portion 1 has the conductive anti-adhesive film 1B, even if the device is repeatedly used for treating biological tissue, biological tissue is unlikely to adhere to the device and the electrical conductivity can be maintained at a good level. Therefore, the high-frequency device 10 has excellent durability.

[0042] [First Modification] A high-frequency medical device electrode and a medical device according to a first modified example of this embodiment will be described. FIG. 7 is a schematic cross-sectional view of a high-frequency medical device electrode according to a first modified example of the embodiment of the present invention.

[0043] As shown in Fig. 1, a high-frequency device 10A (medical device) of this first modified example includes an electrode part 12 instead of the electrode part 1 in the above embodiment. As shown in Fig. 2, the electrode part 12 in this first modified example includes a conductive adhesion prevention film 1B (coating film) including a filler 5A having a shape different from that of the above embodiment. The following description will focus on the differences from the above embodiment.

[0044] 5, the conductive adhesion prevention film 1B has a silicone resin 4 similar to that of the above embodiment, and a filler 5A having a shape different from that of the above embodiment. The filler 5A is formed in a long and thin flake shape having corners 5a. As in the above embodiment, the filler 5A also has an average particle size in the longitudinal direction of 3 μm or more, which is smaller than the film thickness of the conductive adhesion prevention film 1B, and a true density of 11 g / cm. 3It is more preferable that the thickness is less than 1 mm. Also, in the conductive adhesion prevention film 1B of the first modification, the fillers 5A are bonded to each other, and at least one of the fillers 5A and the electrode base material 1A located on the surface of the treatment part is bonded by thermal fusion. The corners 5a of the fillers 5A are easily melted by heat, and are easily fused to other adjacent fillers 5A.

[0045] In Fig. 5, the filler 5A is depicted as extending straight. However, as in the above embodiment, the filler 5A is not limited to a straight shape as long as it can be well dispersed in the conductive anti-adhesive film 1B. The filler 5A may be curved or bent as long as it can be arranged within a range of about the thickness of the conductive anti-adhesive film 1B in a dispersed state in the conductive anti-adhesive film 1B.

[0046] In the conductive adhesion prevention film 1B according to the first modification, the amount of the filler 5A added is preferably in the range of, for example, 60 wt % to 90 wt %, similar to the above embodiment. Furthermore, the average particle size of the filler 5A is preferably 2 μm or more, similar to the above embodiment. The material of the filler 5A is the same as that of the above embodiment, and may be a metal. The electric resistivity of the metal used for the filler 5A may be, for example, 9Ω or less. Examples of metals with low electric resistivity include silver, nickel, copper, and gold.

[0047] According to the high-frequency device 10A of the first modification, since the surface of the electrode section 11 has the conductive anti-adhesive film 1B, even if the device is repeatedly used for treating living tissue, the living tissue is unlikely to adhere thereto and the electrical conductivity can be maintained at a good level. Therefore, the high-frequency device 10A has excellent durability. In particular, in this first modified example, since the filler 5A is elongated and has a shape with corners, even a small amount of the filler 5A is easily fused to each other, and it is possible to more reliably form a conductive path. That is, by setting the amount of the filler 5A to be added to, for example, about 60 wt%, the area of ​​the filler 5A exposed on the electrode surface 1b can be kept small, and the gap between the exposed parts 5b of the filler 5A can be prevented from becoming too narrow. As a result, the surface area of ​​the silicone resin 4, which has high biological tissue adhesion prevention performance, can be secured on the electrode surface 1b, and the biological tissue adhesion prevention performance on the electrode surface 1b can be maintained.

[0048] [Second modified example] A high-frequency medical device electrode and a medical device according to a second modified example of this embodiment will be described. FIG. 6 is a schematic cross-sectional view of a high-frequency medical device electrode according to a second modified example of the embodiment of the present invention.

[0049] As shown in Fig. 1, a high-frequency device 10B (medical equipment) of the second modified example includes an electrode section 13 instead of the electrode section 12 in the first modified example. As shown in Fig. 2 and Fig. 6, the electrode section 13 in the second modified example includes a conductive anti-adhesive film 1B (conductive anti-adhesive film for medical use) including two types of fillers 5A and 5B of different sizes. The following description will focus on the differences from the second modified example.

[0050] 6, the conductive adhesion prevention film 1B has the filler 5A in the first modification (referred to as large diameter filler 5A in the second modification) and filler 5B (referred to as small diameter filler 5B in the second modification) having an average particle size smaller than that of the large diameter filler 5A. The filler ratio of the small diameter filler 5B having a smaller particle size is higher in the vicinity of the electrode base material 1A.

[0051] The large diameter filler 5A is mainly dispersed on the electrode surface 1b side of the conductive adhesion preventive film 1B, and is formed in a long and thin flake shape having corners 5a. The large diameter filler 5A is a large filler having an average particle size of 1 μm or more in the longitudinal direction dispersed in the silicone resin 4, and is particularly large in size of 3 μm or more and a true density of 11 g / cm. 3 It is more preferable that: The small diameter filler 5B is mainly dispersed on the electrode substrate surface 1a side of the conductive adhesion prevention film 1B, has a shape similar to that of the large diameter filler 5A, and is formed into a long and thin flake shape having corners 5a. The small diameter filler 5B is a filler having an average particle size in the longitudinal direction of less than 1 μm compared to the large diameter filler 5A and is dispersed in the silicone resin 4. In particular, the small diameter filler 5B may be less than 0.5 μm.

[0052] The large diameter filler 5A and the small diameter filler 5B are both partially melted and bonded to each other by fusion. Furthermore, the small diameter filler 5B is also bonded to the electrode substrate surface 1a of the electrode substrate 1A. The interface between the upper layer in which the large diameter filler 5A is mainly dispersed and the lower layer in which the small diameter filler 5B is mainly dispersed may be clear or unclear. That is, the large diameter filler 5A may be dispersed in the lower layer, and the small diameter filler 5B may be dispersed in the upper layer.

[0053] The large diameter filler 5A and the small diameter filler 5B may be solid or hollow, may be made of a conductive material alone, or may be a non-conductive core coated with a conductive material. The small diameter filler 5B is solid and has a high density, true density of 4.5 g / cm. 3 The large diameter filler 5A has a low density of 3 g / cm 3 Below, it is hollow and has a density of 2g / cm 3 It is more preferable that: When the fillers 5A and 5B are non-conductive cores coated with a conductive material, examples of the non-conductive material include inorganic materials such as glass, silica, alumina, and zirconia.

[0054] According to the high-frequency device 10B of the second modification, since the surface of the electrode portion 12 has the conductive anti-adhesive film 1B, even if the device is repeatedly used for treating living tissue, the living tissue is unlikely to adhere thereto and the electrical conductivity can be maintained at a good level. Therefore, the high-frequency device 10B has excellent durability. In particular, in the second modified example, since the large diameter filler 5A and the small diameter filler 5B are each elongated and have a shape with corners, even a small amount of fillers 5A and 5B can be easily fused to each other, and a conductive path can be more reliably formed. That is, by setting the amount of the large diameter filler 5A to be added to, for example, about 50 wt%, and the amount of the small diameter filler 5B to be added to, for example, about 10 wt%, the area of ​​the large diameter filler 5A exposed on the electrode surface 1b can be kept small, and the interval between the exposed parts 5b of the large diameter filler 5A can be prevented from becoming too narrow. As a result, the surface area of ​​the silicone resin 4, which has high biological tissue adhesion prevention performance, can be secured on the electrode surface 1b, and the biological tissue adhesion prevention performance on the electrode surface 1b can be maintained.

[0055] In the second modified example, since the small diameter filler 5B has a small average particle size, a large number of fused portions with the electrode base material 1A are formed, and high adhesion to the electrode base material 1A is obtained. In the second modification, the conductive adhesion prevention film 1B has a layer mainly containing large-diameter filler 5A and a layer mainly containing small-diameter filler particles, both of which are formed of the same silicone resin 4, so that high adhesion can be obtained. That is, when only small-diameter filler 5B is provided, it is easy for the filler particles to accumulate in the vicinity of the electrode base material 1A, and adhesion to the electrode base material 1A can be ensured, but the density on the electrode surface 1b side is reduced, so that the small-diameter filler particles 5B are fused and joined together on the electrode surface 1b side, and sufficient conductive paths cannot be formed. On the other hand, when only large-diameter filler 5A is used as in the first modification, sufficient adhesion may not be obtained because there are few joints with the electrode base material 1A. Therefore, by using two types of fillers with different particle sizes, large-diameter filler 5A and small-diameter filler 5B, as in the second modification, a configuration is obtained in which high adhesion and conductivity can be achieved in a well-balanced manner.

[0056] Furthermore, by setting the average particle size of the small diameter filler 5B to 1 μm or less, more preferably 0.5 μm or less, it is possible to increase the fusion area with the electrode base material 1 A. Furthermore, by setting the average particle size of the large diameter filler 5A to more than 1 μm, more preferably 4 μm or more, it is possible to efficiently form a conductive path even if the amount of the filler added to the silicone resin 4 is small, and it is possible to increase the silicone resin ratio for exhibiting anti-sticking properties.

[0057] Furthermore, if a layer is formed with paint containing only small diameter filler 5B and then a layer is formed with paint containing only large diameter filler 5A, the same performance can be achieved with small amounts of each, and the interface between each layer becomes clear. Furthermore, in the second modified example, if a solid, high-density small-diameter filler 5B is used, it will settle after painting and will tend to gather near the electrode substrate 1A. If a low-density large-diameter filler 5A is used, it will not settle after painting and will be uniformly dispersed from the vicinity of the electrode substrate 1A to the electrode surface 1b, allowing efficient formation of conductive paths. In particular, hollow materials plated with metal have the lowest density and can be dispersed stably.

[0058] [Third Modification] A high-frequency medical device electrode and a medical device according to a third modified example of this embodiment will be described. FIG. 7 is a schematic cross-sectional view of a high-frequency medical device electrode according to a third modified example of the embodiment of the present invention.

[0059] As shown in Fig. 1, a high-frequency device 10C (medical equipment) of the third modified example includes an electrode section 14 instead of the electrode section 1 in the above embodiment. As shown in Fig. 2 and Fig. 7, the electrode section 14 in the third modified example includes a conductive anti-adhesive film 1B (conductive anti-adhesive film for medical use) including spherical filler 5C instead of the flake-shaped filler 5 of the embodiment. The following description will focus on the differences from the above embodiment.

[0060] 7, the filler 5C added to the silicone resin 4 of the conductive adhesion preventive film 1B is formed in a spherical shape. As in the above embodiment, the spherical filler 5C also has an average particle size in the longitudinal direction of 3 μm or more and a true density of 11 g / cm 3 It is more preferable that the following is satisfied. Also in the conductive adhesion preventive film 1B of the third modified example, at least one of the fillers 5C are joined by surface bonding between themselves and the fillers 5C and the electrode base material 1A located on the surface of the treatment portion by thermal fusion.

[0061] The amount of filler 5C added according to the third modification is preferably, for example, 70 wt %. Furthermore, the average particle size of filler 5C is preferably 7 μm or more. The material of the filler 5C is the same as that of the above embodiment, and may be a metal. The electric resistivity of the metal used for the filler 5C may be, for example, 9Ω or less. Examples of metals with low electric resistivity include silver, nickel, copper, and gold.

[0062] According to the high-frequency device 10C of the third modification, since the surface of the electrode portion 13 has the conductive anti-adhesive film 1B, even if the device is repeatedly used for treating living tissue, the living tissue is unlikely to adhere thereto and the electrical conductivity can be maintained at a good level. Therefore, the high-frequency device 10C has excellent durability. By setting the amount of filler 5C to about 70 wt %, for example, the area of ​​the filler 5C exposed on the electrode surface 1b can be kept small, and the intervals between the exposed portions 5b of the filler 5C can be prevented from becoming too narrow. As a result, the surface area of ​​the silicone resin 4, which has high biological tissue adhesion prevention performance, can be secured on the electrode surface 1b, and the biological tissue adhesion prevention performance on the electrode surface 1b can be maintained.

[0063] [Fourth Variation] A high-frequency medical device electrode and a medical device according to a fourth modified example of this embodiment will be described. FIG. 8 is a schematic cross-sectional view of a high-frequency medical device electrode according to a fourth modified example of the embodiment of the present invention.

[0064] As shown in Fig. 1, a high-frequency device 10D (medical equipment) of the fourth modified example includes an electrode section 15 instead of the electrode section 11 in the first modified example. As shown in Fig. 2 and Fig. 8, the electrode section 15 in the fourth modified example includes a conductive anti-adhesive film 1B (conductive anti-adhesive film for medical use) including spherical filler 5D instead of the flake-shaped filler 5 of the embodiment. The following description will focus on the differences from the above embodiment.

[0065] 8, the filler 5D added to the silicone resin 4 of the conductive adhesion preventive film 1B is formed into an elongated elliptical shape. As in the above embodiment, the filler 5D also has an average particle size in the longitudinal direction of 3 μm or more and a true density of 11 g / cm. 3 It is more preferable that the following is satisfied. Also in the conductive adhesion preventive film 1B of the fourth modified example, at least one of the fillers 5D themselves and the fillers 5D and the electrode base material 1A located on the surface of the treatment portion is joined by surface bonding through thermal fusion.

[0066] The amount of filler 5D added according to the fourth modification is preferably, for example, 70 wt %. Furthermore, the average particle size of filler 5D is preferably 7 μm or more. The material of the filler 5D is the same as that of the above embodiment, and may be a metal. The electric resistivity of the metal used for the filler 5A may be, for example, 9Ω or less. Examples of metals with low electric resistivity include silver, nickel, copper, and gold.

[0067] According to the high-frequency device 10D of the fourth modification, since the surface of the electrode portion 15 has the conductive anti-adhesive film 1B, even if the device is repeatedly used for treating living tissue, the living tissue is unlikely to adhere thereto and the electrical conductivity can be maintained at a good level. Therefore, the high-frequency device 10D has excellent durability. By setting the amount of filler 5D to about 70 wt%, for example, the area of ​​the filler 5D exposed on the electrode surface 1b can be kept small, and the intervals between the exposed portions 5b of the filler 5D can be prevented from becoming too narrow. As a result, the surface area of ​​the silicone resin 4, which has high biological tissue adhesion prevention performance, can be secured on the electrode surface 1b, and the biological tissue adhesion prevention performance on the electrode surface 1b can be maintained.

[0068] (First embodiment) Next, Examples 1 to 5 of electrodes for high-frequency medical devices corresponding to the above-mentioned embodiment, the first modified example, and the second modified example in the first example will be described together with Comparative Examples 1 to 6. The schematic configurations and evaluation results of each Example and Comparative Example are shown in [Table 1] and [Table 2] below.

[0069] [Table 1]

[0070] [Table 2]

[0071] Silicone resin was used as the material of the silicone resin 4 of the electrodes used in Examples 1 to 5 and Comparative Examples 1 to 6. Generally, silicone resin refers to a film in which the silicone resin is mainly composed of siloxane bonds (T units) in a three-dimensional shape and has a high crosslinking density and is hard, while silicone rubber refers to a film in which the silicone resin is mainly composed of siloxane bonds (D units) in a two-dimensional shape and is flexible. The silicone resin in this embodiment refers to a silicone that combines hardness that ensures scratch resistance and flexibility that can follow the thermal expansion and contraction of the base material by combining silicone resin and silicone rubber. Specifically, SILRES (registered trademark) MPF52E (trade name; manufactured by Wacker Asahi Kasei Silicone Co., Ltd.) was used as the silicone resin.

[0072] As shown in [Table 1] and [Table 2], the conductive fillers (abbreviated simply as "filler" in [Table 1] and [Table 2]) used in Examples 1 to 5 and Comparative Examples 1 to 6 include cases where one type was used (Examples 1 to 4 and Comparative Examples 1 to 6) and cases where two types were used (Example 5). In the case where one type of filler was used, the filler material and characteristics listed under "Filler (1)" in [Table 1] and [Table 2] were used. In the case where two types of filler were used, the filler material and physical property values ​​listed under "Filler (1)" and "Filler (2)" in [Table 1] and [Table 2] were used.

[0073] In addition, in [Table 1] and [Table 2], the conductive fillers used in this embodiment are six specific commercially available types indicated with "a", "b", "c", "d", "e", and "f", and conductive fillers other than these six types are indicated with "-". Furthermore, these conductive fillers "a" to "f" are referred to as fillers a to f, respectively, and have the shapes and forms shown in the schematic diagrams of Figures 9A to 9F. Note that Figure 9G was not used in Examples 1 to 5 and Comparative Examples 1 to 6, but is listed as a reference for adhesion. The materials and physical properties, amount added (wt%), curing temperature (° C.), conductivity, adhesion, and evaluation methods of the specific conductive fillers used in Examples 1 to 5 and Comparative Examples 1 to 6 will be specifically described below.

[0074] [Example 1] Example 1 is an example of the electrode for high-frequency medical equipment according to the above embodiment. As shown in [Table 1], filler (1) is made by adding silver filler in the form of flakes with corners, and curing it at 150°C or higher, causing the corners to melt and the filler particles to fuse together. Specifically, the filler is made of silver, has a flake shape with corners, an average particle size of 2 μm, and a true density of 10.5 g / cm. 3 The filler was added in an amount of 90 wt% and dried at a curing temperature of 150°C to form a film.

[0075] [Example 2] Example 2 is an example of the electrode for high-frequency medical equipment according to the above embodiment. As shown in [Table 1], filler (1) is made by adding silver filler in the form of flakes with corners, and curing it at 150°C or higher, causing the corners to melt and the filler particles to fuse together. Specifically, the filler is made of silver, has a flake shape with corners, an average particle size of 3.5 μm, and a true density of 12.0 g / cm. 3 The filler was added in an amount of 90 wt% and dried at a curing temperature of 150°C to form a film.

[0076] [Example 3] Example 3 is an example of the electrode for high-frequency medical equipment according to the above embodiment. As shown in [Table 1], filler (1) is made by using filler a, adding silver filler in a flake shape with corners, and curing at a curing temperature of 150°C, whereby the corners melt and the filler particles fuse together (see Figure 9A). Specifically, filler a is made of silver, has a flake shape with corners, has an average particle size of 3.5 μm, and a true density of 10.5 g / cm. 3 Filler a was added in an amount of 80 wt% and dried at a curing temperature of 150°C to form a film.

[0077] [Example 4] Example 4 is an example of the electrode for high-frequency medical equipment according to the above embodiment. As shown in [Table 1], filler (1) is made of filler b, which is made by adding metal-coated filler having angular flake shape and curing at a curing temperature of 200°C, whereby the corners melt and the filler particles fuse together (see Fig. 9B). Specifically, filler b is made of alumina coated with silver, has angular flake shape, has an average particle size of 13 μm, and a true density of 5.8 g / cm. 3 Filler b was added in an amount of 60 wt% and dried at a curing temperature of 200°C to form a film.

[0078] [Example 5] Example 5 is an example of the electrode for a high-frequency medical device according to the second modified example. As shown in [Table 1], two types of filler are used: (1) with a large particle size and (2) with a small particle size. Filler (1) is made by adding filler a, which is in the form of angular flakes, and curing at a curing temperature of 180°C, melting the corners and fusing the fillers together. Specifically, filler a is made of silver, in the form of angular flakes, with an average particle size of 3.5 μm and a true density of 10.5 g / cm. 3 Filler (2) was made by adding filler e, which has a smaller diameter and higher density than filler a, and melting it by hardening it at a hardening temperature of 180°C, fusing the fillers together (see Figure 9E). Specifically, filler e is made of silver, has an average particle size of 0.8 μm, and a true density of 10.5 g / cm. 3 Fillers a and e were added in amounts of 50 wt% and 10 wt%, respectively, and were dried at a curing temperature of 180°C to form films. Example 5 is an example of the above-mentioned Example 1 to which filler e having a small particle size and high density is added, so that the small, high-density filler e is concentrated and arranged in the vicinity of the electrode substrate.

[0079] [Comparative Examples 1 to 6] Comparative Examples 1 to 6 will be described, focusing on the differences from the above Examples 1 to 5. In Comparative Examples 1 and 2, as shown in Table 2, the same filler a as in Example 3 is used. Comparative Example 1 differs from Example 3 in that the curing temperature is 140°C. Comparative Example 1 was formed at a curing temperature 10°C lower than Example 3, which has a curing temperature of 150°C. Comparative Example 2 differs from Example 3 in that the additive amount is 95wt% and the curing temperature is 140°C. Comparative Example 2 has an additive amount of 80wt%. Compared to Example 3, which has a curing temperature of 150°C, the additive amount is 15wt% higher and the curing temperature is 10°C lower.

[0080] In Comparative Example 3, as shown in Table 2, filler c was used, a metal-coated filler with no corners and a flake shape was added, and the filler was cured at a curing temperature of 200°C (see Fig. 9C). Specifically, filler c is a material with a silver coating on the body, a flake shape with no corners, an average particle size of 6.5 µm, and a true density of 9.2 g / cm. 3 Filler c was added in an amount of 88 wt %, and dried to form a film at a curing temperature of 200° C. The filler of Comparative Example 3 differs from Examples 1 to 5 in that it has a flaky shape without corners.

[0081] In Comparative Example 4, as shown in Table 2, Filler d was used, a spherical metal-coated filler was added, and the filler was cured at a curing temperature of 200°C (see Fig. 9D). Specifically, Filler d is made of aluminum coated with silver, has a spherical shape, an average particle size of 7.0 µm, and a true density of 3.5 g / cm. 3 Filler d was added in an amount of 73 wt %, and dried to form a film at a curing temperature of 200° C. The filler in Comparative Example 3 differs from Examples 1 to 5 in that it is spherical, not flaky.

[0082] In Comparative Example 5, as shown in Table 2, filler e was used, a silver filler having a smaller diameter and a higher density than the other fillers a, b, c, and d was added, and the filler was cured at a curing temperature of 150° C. (See FIG. 9E.) Specifically, filler e is made of silver, has an average particle size of 0.8 μm, and has a true density of 10.5 g / cm. 3 Filler e was added in an amount of 96 wt% and dried at a curing temperature of 150°C to form a film.

[0083] In Comparative Example 6, as shown in [Table 2], filler f was used, a filler made of fine carbon particles was added, and the curing temperature was 150°C (see FIG. 9F). Specifically, filler f is fine particles made of carbon, with an average particle size of 0.04 μm and an unknown true density. Filler f was added in an amount of 17 wt%, and dried at a curing temperature of 150°C to form a film.

[0084] Here, Fig. 9G is a reference example of a filler that is not adopted in the above-mentioned Examples 1 to 5 and Comparative Examples 1 to 6. The filler shown in Fig. 9G is a spherical filler made of silver, with an average particle size of 3.9 µm and a true density of 10.5 g / cm 3 The amount of this filler added is said to be 96 wt%.

[0085] [Evaluation method] The test samples of Examples 1 to 5 and Comparative Examples 1 to 6 were subjected to an electrical conductivity evaluation and a filler adhesion evaluation.

[0086] In the conductivity evaluation, an electrode according to the embodiment (Examples 1 to 5, Comparative Examples 1 to 6) was attached to the tip of the blood vessel sealing device. Then, the electrode portion was used to grasp and press a pig's blood vessel, and high frequency was applied while the blood vessel was blocked. Devices that were able to seal the blood vessel were evaluated as having "good" conductivity (listed as "A" in [Table 1]), and devices that were not able to seal the blood vessel were evaluated as having "poor" conductivity (listed as "B" in [Table 1]).

[0087] Filler Adhesion Evaluation In the adhesion prevention evaluation, the number of times blood vessels can be sealed in the above-mentioned conductivity evaluation is counted. That is, the number of times blood vessels can be sealed when the fillers peel off from each other or when the filler and the electrode substrate peel off is counted, and this number is called the number of times blood vessels can be sealed. Then, when the number of times blood vessels can be sealed is 5 or less, the adhesion (written as "adhesion" in [Table 1] and [Table 2]) is "poor" (the number is written with "B" in [Table 1] and [Table 2]), and when it is 30 or more, the adhesion is "good" (the number is written with "A" in [Table 1] and [Table 2]). Furthermore, when it is 60 or more times, which is the most suitable number of times blood vessels can be sealed in one treatment, and has particularly good adhesion, it is written as "AA" in [Table 1] and [Table 2].

[0088] [Evaluation Results] As shown in [Table 1], the electrical conductivity and filler adhesion were evaluated as "A" or "AA", i.e., "good" in Examples 1 to 5. Since it was confirmed that sufficient electrical conductivity was obtained and the filler was melted and fused to the substrate in Examples 1 to 5, it is considered that sufficient durability was obtained. In Example 3, a flake-shaped silver filler (filler a) having an average particle size of 3 μm or more and a true density of 11 g / cm 3 It was found that by adding the amount below this, the particles are less likely to sink and are more likely to be uniformly dispersed in the silicone resin, and good electrical conductivity can be obtained even with an addition amount of 80 wt %, which is less than in Examples 1 and 2.

[0089] In Example 4, by using a filler (filler b) in which an angular filler is used as a core and metal-coated with alumina, it is possible to reduce costs compared to the use of silver as in Examples 1 to 3. In addition, by using a core with a low specific gravity such as alumina or silica as in Example 4, the filler is less likely to sink, and it was found that conductivity can be obtained with even a small amount. In Example 5, in addition to Filler a in Example 1, Filler e, which has a small particle size and high density, is mixed. Therefore, it is believed that by curing at high temperatures, fusion between the substrate and the filler occurs, resulting in higher adhesion strength.

[0090] In contrast, in Comparative Examples 1 to 6, at least one of the electrical conductivity evaluation and the filler adhesion evaluation was "poor." In the electrical conductivity evaluation, Comparative Examples 1 and 6 were "B" and "poor." In the filler adhesion evaluation, Comparative Examples 2 to 6 were "B" and "poor," and Comparative Example 1 was not rated. In Comparative Example 1, the curing temperature was 140°C, which is lower than in Examples 1 to 5, and therefore fusion between the fillers did not occur, which is considered to be the reason why the adhesion could not be evaluated. As a result, it was confirmed that sufficient conductivity was not obtained. In Comparative Example 2, compared to Examples 1 to 5, even if the curing temperature is low, the amount of filler added can be increased to increase the number of contact points between the fillers and obtain electrical conductivity. However, it was confirmed that no fusion with the electrode substrate occurs, and furthermore, it is considered that the adhesion between the silicone resin and the electrode substrate is hindered, and therefore it is understood that sufficient adhesion cannot be obtained.

[0091] In Comparative Example 3, the filler (filler c) has a flake shape without corners, so it can be confirmed that the filler does not fuse to itself due to melting of the corners, as compared with Examples 1 to 5. In order to ensure conductivity, it is necessary to add a large amount of filler, but in that case, the adhesion between the electrode base material and the silicone resin is hindered, and sufficient adhesion cannot be obtained. In Comparative Example 4, compared to Examples 1 to 5, the filler (filler d) is spherical and has no corners, and therefore, it can be confirmed that fusion between the fillers due to melting of the corners does not occur, as in Comparative Example 3. In order to ensure conductivity, it is necessary to add a large amount of filler, but in that case, the adhesion between the electrode base material and the silicone resin is hindered, and sufficient adhesion cannot be obtained.

[0092] In Comparative Example 5, a filler (filler e) having a smaller average particle size is used compared to Examples 1 to 5, so the amount of filler added needs to be increased to form a conductive path, which hinders adhesion between the electrode base material and the silicone resin, making it difficult to obtain sufficient adhesion. In Comparative Example 6, the average particle size of the carbon filler (filler f) is extremely small compared to Examples 1 to 5, so sufficient conductivity cannot be obtained even if a large amount of filler is added. In addition, although the weight ratio is small, the density is low, so the volume ratio is extremely large, and therefore adhesion cannot be obtained.

[0093] (Second Example) Next, Examples 1 and 2 of the high-frequency medical device electrodes corresponding to the above-mentioned embodiment, the first modification, and the second modification in the second example will be described together with Comparative Examples 1 to 3. The schematic configuration and evaluation results of each Example and Comparative Example are shown in [Table 3] below. In the second example, an anti-adhesion evaluation was carried out to evaluate the performance of preventing adhesion of biological tissue during repeated use of the electrodes for high-frequency medical equipment.

[0094] [Table 3]

[0095] As shown in Table 3, in Example 1, filler a having a particle size of 1 μm and filler b having a particle size of 4.5 μm were added to a silicone resin and a solvent, and the mixture was applied to an electrode substrate. After application, the mixture was left to stand for 30 minutes, and then baked at a baking temperature of 260° C. for a baking time of 3 hours. In Example 2, filler a having a particle size of 1 μm and filler b having a particle size of 4.0 μm were added to a silicone resin and a solvent, and the mixture was applied to an electrode substrate. After application, the mixture was left to stand for 30 minutes, and then baked at a baking temperature of 160° C. for a baking time of 0.5 hours (30 minutes). The small medium-sized fillers in Examples 1 and 2 settle when left to stand for 30 minutes and are distributed intensively near the electrode substrate. When the fillers are heated to 260°C, the ends of the fillers melt, forming fusion bonds between the fillers and the substrate, and between the fillers themselves.

[0096] As shown in Table 3, Comparative Examples 1 to 3 were produced by changing the particle size of the filler, the firing temperature (° C.), and the firing time (H) compared to Examples 1 and 2. The standing time after application was 30 minutes, the same as in the Examples.

[0097] [Evaluation method] In the evaluation of adhesion prevention according to the second embodiment, the omentum was immersed in a mixture of blood and physiological saline. The omentum was then removed, and 50 sealings were performed using the same blood vessel sealing device as in the first embodiment described above. That is, as shown in Table 3, the omentum was grasped and pressed with the electrode, and high frequency was applied. The adhesion rate (%) was calculated as the number of times omentum was attached / 50 times x 100, and a rate of adhesion of less than 30% was evaluated as "pass" (listed as "A" in Table 3), and a rate of adhesion of 30% or more was evaluated as "fail" (listed as "B" in Table 3).

[0098] [Evaluation Results] As shown in Table 3, the adhesion rate was 15% in Example 1 and 0% in Example 2, both of which were less than 30%, and the adhesion prevention evaluation was "A" and "passed." In particular, in Example 2, the net oil did not adhere even once during the 50 times, and there was no peeling.

[0099] In contrast to this, in all of Comparative Examples 1 to 3, the sticking rate was 30% or more, and the adhesion prevention evaluation was "B" and "failed."

[0100] Although the preferred embodiment and each modification of the present invention have been described above along with each example, the present invention is not limited to these embodiments, each modification, and each example. Addition, omission, substitution, and other modifications of the configuration are possible within the scope of the gist of the present invention. Furthermore, the present invention is not limited by the foregoing description, but only by the scope of the appended claims.

[0101] For example, in the above-described embodiment and each modified example, the medical device provided with the medical conductive anti-adhesive film is a high-frequency device, but the medical device is not limited to the high-frequency device. Examples of other medical devices suitable for using the medical conductive anti-adhesive film of the present invention include treatment tools such as electric scalpels, high-frequency devices, bipolar tweezers, probes, and snares.

[0102] In the above embodiment and each modified example, the medical conductive anti-adhesive film is laminated directly on the electrode base material 1A, but a conductive single-layer or multi-layer intermediate layer may be interposed between the electrode base material 1A and the medical conductive anti-adhesive film. As the intermediate layer, a suitable conductive layer that improves the bonding strength between the electrode base material 1A and the medical conductive anti-adhesive film may be used. [Industrial Applicability]

[0103] The present invention can be used in electrodes for high-frequency medical devices and in medical devices. [Explanation of symbols]

[0104] 1, 11, 12, 13, 14 electrode part 1a Electrode base material surface 1A electrode base material 1b Electrode surface 1B Conductive anti-adhesion film (coating film) 4. Silicone Resin 5. 5A~5D Filler 5a Corner 10, 10A~10D High frequency devices (medical equipment) 51 Fusion part

Claims

1. A high-frequency medical device electrode having a coating film formed on at least a part of a surface of a treatment portion of the medical device, The coating film is A silicone resin, At least one type of filler having electrical conductivity; At least one of the fillers and the filler and an electrode base material located on the surface of the treatment portion is fusion-bonded to form a conductive path; the electrode surface of the coating film has an exposed portion where the filler is exposed from the silicone resin, and a smooth surface made of the silicone resin excluding the exposed portion; an area of ​​the exposed portion in a plan view is smaller than a surface area of ​​the silicone resin; The filler is composed of two or more types of fillers having different particle sizes, An electrode for a high frequency medical device, wherein the proportion of filler having a small particle size is high in the vicinity of the electrode base material.

2. A high-frequency medical device electrode having a coating film formed on at least a part of a surface of a treatment portion of the medical device, The coating film is A silicone resin, At least one type of filler having electrical conductivity; At least one of the fillers and the filler and an electrode base material located on the surface of the treatment portion is fusion-bonded to form a conductive path; The filler is composed of two or more types of fillers having different particle sizes, An electrode for a high frequency medical device, wherein the proportion of filler having a small particle size is high in the vicinity of the electrode base material.

3. The electrode for use in a high-frequency medical device according to claim 1 or 2, wherein the filler has a shape having corners.

4. The high frequency medical device electrode according to any one of claims 1 to 3, wherein the filler is a core made of aluminum, copper, alumina, silica, glass, ceramic such as calcium titanate fiber, resin such as acrylic, hollow particles, or rubber, coated with silver.

5. A medical device comprising the high-frequency medical device electrode according to any one of claims 1 to 4.

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