Surgical electrode having surface treatment coating

Abstract

The purpose of the present invention is to provide a surgical electrode for an electrosurgical instrument for use in the surgery of biological tissue, the surgical electrode having a surface treatment coating with a specific infrared absorption spectrum at the tip-end portion of the surgical electrode, the surgical electrode thus being made less prone to the adhesion of carbonized substances such as biological tissue, and having a coating with excellent adhesion. In particular, the surgical electrode exhibits good burnt residue resistance both under high blood content conditions and high protein / lipid content conditions. The present disclosure relates to a surgical electrode for an electrosurgical instrument for use in the surgery of biological tissue, the surgical electrode comprising a tip-end portion capable of emitting high frequencies. The tip-end portion has a surface treatment coating. The surface treatment coating has a peak (α) in the range of 950 cm-1 to 1060 cm-1, a peak (β) in the range of 720 cm-1 to 830 cm-1, and a peak (γ) in the range of 450 cm-1 to 495 cm-1 in the infrared absorption spectrum. The ratio (βA / αA) of the peak intensity (βA) of the peak β to the peak intensity (αA) of the peak α is 0.770 to 1.040.

Description

Surgical electrodes with surface treatment coatings

[0001] The present invention relates to a surgical electrode having a surface treatment coating that is used as a medical device and is suitable for use with electrosurgical instruments used in surgery on living tissue.

[0002] Electrosurgical instruments (so-called electrosurgical scalpels) are essential in surgical procedures, as they can stop bleeding (coagulate) and cut tissue by discharging high-frequency current generated from the device through surgical electrodes. One known problem associated with the use of electrosurgical scalpels is the formation of eschar, which occurs when charred tissue or other materials adhere to the tip of the scalpel. To address this problem, a method for mass-producing multiple electrodes, each of which can be connected to an appropriate power source for surgical procedures, has been proposed (see Patent Document 1). The method includes the steps of preparing a conductive stock material having a shape and dimensions suitable for forming multiple electrode blanks, coating at least a portion of the stock material with a non-adhesive layer, and forming the coated electrode blanks.

[0003] Japanese Patent Application Laid-Open No. 2000-333968

[0004] However, the technology described in Patent Document 1 suffers from the problem that the coated non-adhesive layer is damaged by Joule heat and discharge voltage due to the high-frequency current emitted from the tip of the electric scalpel, resulting in peeling and loss of the non-adhesive layer. In particular, the degree of scorching tends to vary depending on the incision site (e.g., when there is a high level of protein or lipid or blood), hindering stable surgery. The present invention aims to solve these problems and provides a surgical electrode for an electrosurgical instrument used in surgery on biological tissue, which has a coating that is resistant to adhesion of carbides such as biological tissue and has excellent adhesion. In particular, the electrode exhibits good scorching resistance under both high blood and high protein and lipid conditions.

[0005] The inventors conducted extensive research to solve the above problems and discovered that by providing a surface treatment coating with a specific infrared absorption spectrum at the tip of a surgical electrode, it is possible to provide a surgical electrode with a coating that is less likely to attract carbonized matter such as biological tissue under various conditions and has excellent adhesion, thereby completing the present invention.

[0006] That is, the present invention may include the following: <1> A surgical electrode of an electrosurgical instrument used in surgery on living tissue, the surgical electrode having a tip portion capable of emitting high frequency waves, the tip portion having a surface treatment coating, and the surface treatment coating having a wavelength of 950 cm in an infrared absorption spectrum. －１ From 1060cm －１ and a peak (α) in the range of 720 cm －１ From 830 cm －１ and a peak (β) in the range of 450 cm －１ From 495 cm －１ and the peak intensity (α Ａ ) with respect to the peak intensity of the peak β (β Ａ ) ratio (β Ａ / α Ａ ) is in the range of 0.770 to 1.040. <2> The surgical electrode according to <1>, wherein the surface treatment coating contains a silicone resin (A), and the silicone resin (A) contains a structural unit consisting of D units and a structural unit consisting of T units. <3> The surgical electrode according to <2>, wherein the surface treatment coating contains an inorganic oxide (B) containing silicon. <4> The surgical electrode according to any one of <1> to <3>, wherein the tip portion further comprises a base coating formed from a surface treatment agent (Y) containing a compound (D) having an amino group.

[0007] The present invention provides a surgical electrode for an electrosurgical instrument used in surgery on living tissue, which is resistant to adhesion of carbonized matter such as living tissue under various conditions and exhibits high performance with excellent adhesion.

[0008] FIG. 1 is a schematic diagram showing an example of a surgical electrode (electric scalpel) (blade electrode). FIG. 2 is a schematic diagram showing an example of a surgical electrode (electric scalpel) (loop electrode). FIG. 3 is a schematic diagram showing an example of a surgical electrode (electric scalpel) (ball electrode). FIG. 4 is a schematic diagram showing an example of a surgical electrode (electric scalpel) (needle electrode). FIG. 5 is a schematic diagram showing an example of a surgical electrode (laparoscopy). (a) shows a wire L-hook type, (b) shows a straight spatula type, (c) shows a wire J-hook type, and (d) shows a syringe type. FIG. 6 is a schematic diagram showing an example of a surgical electrode (electric scalpel) (bipolar). FIG. 7 is a schematic diagram showing an example of forming a base coating on a surgical electrode. FIG. 8 is a schematic diagram showing an example of forming a base coating and a surface treatment coating on a surgical electrode.

[0009] The surgical electrode having a surface treatment coating according to an embodiment of the present invention is used in surgery on living tissue and has a specific surface treatment coating on or at the surface of the tip of the surgical electrode. Note that a passive film or an iron oxide film may be present between the tip of the surgical electrode and the surface treatment coating, but these films are not required.

[0010] <Surgical Electrode> A surgical electrode is an electrode detachably attached to the tip of an electrosurgical instrument such as an electrosurgical scalpel. By emitting high-frequency waves from the tip of the electrode to biological tissue, it can stop bleeding (coagulate) or incise biological tissue. Surgical electrodes are made of conductive materials. More specifically, examples of materials include iron-based metals, zinc-plated metals, aluminum-based metals, magnesium-based metals, nickel-based metals, titanium-based metals, zirconium-based metals, copper-based metals, tin-based metals, tungsten-based metals, chromium-based metals, manganese-based metals, molybdenum-based metals, and cobalt-based metals, with stainless steel being more preferred. Typical electrosurgical instruments to which surgical electrodes are attached include electrosurgical scalpels such as monopolar and bipolar scalpels, laparoscopes, and the like. A schematic diagram of an example surgical electrode is shown in FIG. 1.

[0011] Figure 1 shows an example of a blade-type surgical electrode with a plate-shaped tip. The surgical electrode 10 is a component that can be attached to and detached from the main body of an electrosurgical instrument (not shown). The surgical electrode 10 is composed of an electrical connection portion 13 that is electrically connected to the main body of the electrosurgical instrument, a tip portion 11 that emits high-frequency waves when placed in close proximity to biological tissue, and an intermediate portion 12 that connects the electrical connection portion 13 to the tip portion 11.

[0012] <Tip> The tip 11 is the portion that emits high-frequency waves when placed close to biological tissue. The shape of the tip is not particularly limited, and examples include the tip 11 of the blade-type surgical electrode 10 shown in FIG. 1 , the tip 21 of the loop-type surgical electrode 20 shown in FIG. 2 , the tip 31 of the ball-type surgical electrode 30 shown in FIG. 3 , and the tip 41 of the needle-type surgical electrode 40 shown in FIG. 4 , all of which are surgical electrodes used as scalpel tips for electrocauteries. Other surgical electrodes that can be attached to laparoscopes include the wire L-shaped hook type (a) shown in FIG. 5 , the straight spatula type (b) shown in FIG. 5 , the wire J-shaped hook type (c) shown in FIG. 5 , and the syringe type (d) shown in FIG. 5 . While the tips shown so far are the tips of monopolar surgical electrodes, they may also be the tips of bipolar surgical electrodes. An example of the tip 61 of a bipolar surgical electrode 60 is shown in FIG. 6 .

[0013] The tip portion 11 may be a conductive material having at least a portion (e.g., a portion on which a surface treatment coating is to be formed) roughened, or may be unroughened. Examples of roughening methods include, but are not limited to, shot blasting, etching with a solution (such as an acidic or alkaline solution), polishing, plasma treatment, and corona discharge treatment. These treatments may be performed alone or in combination. The surface roughness of the tip portion 11, expressed as an arithmetic mean roughness Ra, is preferably in the range of 0.05 μm to 0.39 μm, more preferably 0.08 μm to 0.25 μm, and particularly preferably 0.10 μm to 0.18 μm. In this specification, "surface roughness" refers to line roughness, and the Ra value is measured using a contact surface roughness meter.

[0014] <Electrical Connection Portion> The electrical connection portion 13 is the portion of the surgical electrode 10 that is electrically connected to the electrosurgical instrument body. The electrical connection portion 13 is detachable from the electrosurgical instrument body and is typically configured so that the electrical connection portion 13 and the electrosurgical instrument body can be fitted together using a mating structure or the like. The electrical connection portion is also made of a conductive material, and the material may be the same as or different from that of the tip portion 11.

[0015] <Intermediate portion> The intermediate portion 12 is a member that connects the tip portion 11 and the electrical connection portion 13. It needs to be made of a conductive material to pass electricity through the tip portion 11, but its shape, length, etc. are not particularly limited. The intermediate portion 12 may have a coating 14. The coating 14 is a cured product of a composition containing an insulating resin. Furthermore, as long as the intermediate portion 12 and the coating 14 are in contact with each other, the size, thickness, shape, etc. of the coating 14 are not particularly limited.

[0016] <Surface Treatment Coating> The surface treatment coating according to this embodiment has an absorption maximum (hereinafter referred to as an absorption peak) at a predetermined wave number in the infrared absorption spectrum. －１ From 1060cm －１ and an absorption peak α (hereinafter referred to as “peak α”) in the range of 720 cm －１ From 830 cm －１ and an absorption peak β (hereinafter referred to as "peak β") in the range of 450 cm －１ From 495 cm －１ In addition, the peak intensity of the peak α (α Ａ ) with respect to the peak intensity of the peak β (β Ａ ) ratio (β Ａ / α Ａ ) is preferably in the range of 0.770 to 1.040, more preferably in the range of 0.830 to 1.034, and even more preferably in the range of 0.950 to 1.023. Ａ / α Ａ When the content is within the above range, good anti-burning properties and adhesion can be obtained.

[0017] Peak α indicates the presence of, for example, Si—O stretching vibration, peak β indicates the presence of, for example, Si—C stretching vibration, and peak γ indicates the presence of, for example, an inorganic solid containing a Si—O bond.

[0018] In addition, the peak intensity α of peak α Ａ The peak intensity of peak γ relative to Ａ ) ratio (γ Ａ / α Ａ ) is preferably in the range of 0.005 to 0.135. Ａ The peak intensity of peak γ relative to Ａ ) ratio (γ Ａ / β Ａ ) is preferably 0.005 to 0.180.

[0019] The method for analyzing the infrared absorption spectrum of the surface treatment film is not particularly limited, but for example, the ATR method, which is a type of infrared spectroscopy, can be used. When analyzing by the ATR method, the device used is a Perkin Elmer FT-IR (Spectrum Two) equipped with an accessory for ATR measurement (GladiATR ＴＭ ) are attached.

[0020] The surface treatment coating according to this embodiment may be formed by any method, provided that the desired absorption intensities are obtained for peaks α, β, and γ. For example, the surface treatment coating may be formed by contacting the surface treatment agent (X) with the surface of the distal end of the surgical electrode. Furthermore, if the distal end of the surgical electrode is provided with a base coating, the surface treatment coating may be formed by contacting the surface treatment agent (X) with the surface of the base coating. The contact of the surface treatment agent (X) may be performed on the distal end or a portion or all of the base coating. The surface treatment coating may be formed on the entire distal end, or on only a portion of the distal end. In the case of a blade-type surgical electrode, examples of the portion include the blade portion of the distal end and the flat portion of the distal end. In this specification, the flat portion refers to the widest area of ​​the blade portion of the distal end 11 shown in FIG. 7.

[0021] In one of the more preferred embodiments, the tip portion is provided with a base coating formed from a surface treatment agent (Y) containing a compound (D) having an amino group.

[0022] In the portion where the surface treatment coating is not formed, only the base coating may be formed. For example, in the case of a blade-type surgical electrode, the base coating may be formed over the entire surface of the blade portion, and the surface treatment coating may be formed only on a portion of that portion. In addition, in the distal end portion 11, only the base coating, or both the base coating and the surface treatment coating may be formed over the entire surface or a portion of the end portion on the intermediate portion 12 side (hereinafter referred to as the "intermediate connection portion").

[0023] <Surface Treatment Agent (X)> The surface treatment agent (X) according to this embodiment preferably contains a silicone resin (A) and a silicon-containing inorganic oxide (B), from the viewpoint of forming a surface treatment coating that satisfies the above-mentioned requirement for peak intensity in an infrared absorption spectrum.

[0024] <Silicone Resin (A)> The silicone resin (A) is not particularly limited as long as it has a plurality of siloxane bonds and an organopolysiloxane structure in which an organic group is bonded to silicon (Si).From the viewpoint that the surface treatment coating satisfies the requirement of the peak intensity of the infrared absorption spectrum, it is preferable to include a silicone resin (A2) containing an organopolysiloxane structure (M unit or D unit) having at least one or two organic groups bonded to Si in one molecule, and a silicone resin (A1) containing an organopolysiloxane structure (T unit or Q unit) having at least three or four organic groups bonded to Si in one molecule.Among these, it is preferable to include a silicone resin (A2) having rubber properties containing D units and a silicone resin (A1) having resin properties containing T units.The position at which the organic group is bonded is not particularly limited, and it may be bonded to the main chain, side chain, or terminal.

[0025] The silicone resin (A) may be a homopolymer having the above-mentioned organopolysiloxane structure, a mixture of a homopolymer having the above-mentioned organopolysiloxane structure and a homopolymer having a polysiloxane structure, or a copolymer (block copolymer or graft polymer) having the above-mentioned organopolysiloxane structure and a polysiloxane structure. The silicone resin (A) may be either an addition type or a condensation type. Furthermore, the silicone resin (A) may be any of a thermosetting type, a room temperature curing type (RTV), and a UV curing type.

[0026] Examples of organic groups bonded to Si in the organopolysiloxane structure include, but are not limited to, saturated hydrocarbon groups, unsaturated hydrocarbon groups, halogenated alkyl groups, and epoxycycloalkyl groups. Examples of saturated hydrocarbon groups include, but are not limited to, linear or branched alkyl groups and cycloalkyl groups. Examples of unsaturated hydrocarbon groups include, but are not limited to, linear or branched alkenyl groups; cycloalkenyl groups; cycloalkenylalkyl groups; and aryl groups. The organic group bonded to Si is preferably an unsaturated hydrocarbon group, more preferably an alkenyl group, and particularly preferably a vinyl group or a hexenyl group.

[0027] Examples of halogenated alkyl groups include chloromethyl, 3-chloropropyl, 1-chloro-2-methylpropyl, and 3,3,3-trifluoropropyl. Examples of epoxycycloalkyl groups include epoxycyclopentyl, epoxycyclohexyl, and epoxycyclooctyl. Examples of linear or branched alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl. Examples of cycloalkyl groups include cyclopentyl and cyclohexyl. Examples of linear or branched alkenyl groups include vinyl, 1-propenyl, allyl, isopropenyl, 1-butenyl, 2-butenyl, pentenyl, and hexenyl. Examples of cycloalkenyl groups include cyclopentenyl and cyclohexenyl. Examples of the cycloalkenylalkyl group include a cyclopentenylethyl group, a cyclohexenylethyl group, a cyclohexenylpropyl group, etc. Examples of the aryl group include a phenyl group, etc.

[0028] The polysiloxane structure is not particularly limited as long as it is different from the above-mentioned organopolysiloxane structure, and examples thereof include a polysiloxane structure having at least two hydrogen atoms bonded to Si in one molecule, and a polysiloxane structure having at least two alkoxy groups bonded to Si in one molecule. Examples of the alkoxy group include a methoxy group, an ethoxy group, a propoxy group, and a butoxy group. The alkoxy group may be linear or branched.

[0029] The above-mentioned various silicone resins (A) may be used alone or in combination of two or more in preparing the surface treatment agent (X). An example of a silicone resin containing T units, which is one preferred embodiment of the silicone resin (A1), is a mixture of a polymer having an organopolysiloxane structure having at least two unsaturated hydrocarbon groups bonded to Si per molecule, and a polymer having a polysiloxane structure having at least two hydrogen atoms bonded to Si per molecule.

[0030] Examples of polymers having an organopolysiloxane structure having at least two unsaturated hydrocarbon groups bonded to Si per molecule include dimethylpolysiloxane having dimethylvinylsiloxy groups at both molecular chain terminals, dimethylsiloxane-methylphenylsiloxane copolymer having dimethylvinylsiloxy groups at both molecular chain terminals, dimethylsiloxane-methylvinylsiloxane copolymer having dimethylvinylsiloxy groups at both molecular chain terminals, dimethylsiloxane-methylvinylsiloxane copolymer having trimethylsiloxy groups at both molecular chain terminals, dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane terpolymer having trimethylsiloxy groups at both molecular chain terminals, dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymer having silanol groups at both molecular chain terminals, and the like. Other examples include polymers in which some of the methyl groups of various homopolymers, copolymers, and terpolymers have been substituted with alkyl groups other than methyl groups, such as ethyl groups and propyl groups, or halogenated alkyl groups, such as 3,3,3-trifluoropropyl groups and 3,3,3-trichloropropyl groups. A mixture of two or more selected from these homopolymers, copolymers, and terpolymers may be used to prepare the surface treatment agent (X).

[0031] The polymer having a polysiloxane structure having at least two hydrogen atoms bonded to Si in one molecule is not particularly limited, but examples thereof include organohydrogenpolysiloxanes having at least two SiH groups in which a hydrogen atom is bonded to Si in one molecule, having repeating diorganosiloxane structures as the main chain, and having a linear, cyclic, branched, or three-dimensional network structure in which both ends of the molecular chain are blocked with triorganosiloxy groups. More specific examples include methylhydrogenpolysiloxanes having trimethylsiloxy groups at both molecular chain terminals, dimethylsiloxane-methylhydrogensiloxane copolymers having trimethylsiloxy groups at both molecular chain terminals, methylhydrogenpolysiloxanes having silanol groups at both molecular chain terminals, dimethylsiloxane-methylhydrogensiloxane copolymers having silanol groups at both molecular chain terminals, dimethylpolysiloxanes having dimethylhydrogensiloxy groups at both molecular chain terminals, methylhydrogenpolysiloxanes having dimethylhydrogensiloxy groups at both molecular chain terminals, dimethylsiloxane-methylhydrogensiloxane copolymers having dimethylhydrogensiloxy groups at both molecular chain terminals, etc. A mixture of two or more selected from these homopolymers and copolymers may also be used to prepare the surface treatment agent (X).

[0032] Examples of the D unit source for the silicone resin containing D units, which is one preferred embodiment of the silicone resin (A2) having rubber properties, include dimethyldisilanol, dimethyldimethoxysilane, dimethyldiethoxysilane, tetramethyldisiloxane, dimethylsiloxane oligomer, methacryloyloxypropyldimethoxymethylsilane, methyldimethoxyphenylsilane, diethoxymethylphenylsilane, methylphenyldisilanol, 1,4-bis(methyldimethoxysilyl)benzene, and 1,4-bis(methyldiethoxysilyl)benzene, and polymers of these are examples of the silicone resin (A2) containing D units.

[0033] The weight average molecular weight of silicone resin (A2) is not particularly limited, but is usually in the range of 3,000 to 70,000, preferably in the range of 3,500 to 65,000. The vinyl equivalent of silicone resin (A1) is not particularly limited, but is usually in the range of 0.3 to 10 mol, preferably 0.5 to 5 mol, of SiH groups per 1 mol of vinyl groups. The weight average molecular weight of silicone resin (A1) is not particularly limited, but is usually in the range of 6,000 to 45,000, preferably 6,500 to 40,000. The weight average molecular weight is measured by GPC (gel permeation column chromatography) and converted into polystyrene.

[0034] <Silicon-Containing Inorganic Oxide (B)> The silicon-containing inorganic oxide (B) is a substance composed of silicon (Si) and oxygen (O), etc., other than an organic compound, and its type is not limited. It also includes silica composed of silicon dioxide, and may be crystalline silica or amorphous silica. Crystalline silica refers to a solid substance having a crystalline structure in which the atoms constituting the crystal are arranged with three-dimensional regular periodicity to form a space lattice. Examples of crystalline silica include quartz, cristobalite, tridymite, etc. Furthermore, amorphous silica refers to a substance in which the atoms are not arranged with regular periodicity and are aggregated without forming a fixed crystalline structure. Examples of amorphous silica include glass, silica gel, fumed silica, diatomaceous earth, etc. Furthermore, the silicon-containing inorganic oxide (B) may be a compound containing a metal element such as sodium, lithium, calcium, magnesium, or zirconium as a constituent component, and examples thereof include sodium silicate, calcium silicate, magnesium silicate, zircon, etc.

[0035] The average particle size of the silicon-containing inorganic oxide (B) is not particularly limited, but is usually in the range of 1 nm to 50 μm, preferably 5 nm to 1 μm. The average particle size can be measured, for example, by averaging the size of 20 or more particles of the inorganic oxide (B) using an electron microscope. In the case of inorganic oxides with a large aspect ratio, the major axis is used to measure the average particle size.

[0036] The method for producing the surface treatment agent (X) according to this embodiment is not particularly limited, and the surface treatment agent (X) can be produced by mixing the silicone resin (A), the silicon-containing inorganic oxide (B), the solvent, the curing agent (C), and the additives.

[0037] The solvent contained in the surface treatment agent (X) is not particularly limited, and examples thereof include organic solvents such as alcohol, acetonitrile, 2-butoxyethanol, propylene glycol monomethyl ether, benzene, ethylbenzene, toluene, xylene, cyclohexane, methyl acetate, 2-ethoxyethyl acetate, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, and methyl isobutyl ketone; and mixtures of these organic solvents with water.

[0038] <Curing Agent (C)> The curing agent contained in the surface treatment agent (X) is not particularly limited as long as it can function as a curing agent for the silicone resin (A), and examples thereof include those containing a metal element selected from titanium, platinum, rhodium, and palladium. Among these, platinum compounds are preferred, and examples of platinum compounds include platinum group metals such as platinum (including platinum black), rhodium, and palladium; ２ PtCl ４ ・nH ２ O, H ２ PtCl ６ ・nH ２ O, NaHPtCl ６ ・nH ２ O, KHPtCl ６ ・nH ２ O, Na ２ PtCl ６ ・nH ２ O.K. ２ PtCl ４ ・nH ２ O, PtCl ４・nH ２ O, PtCl ２ , Na ２ HPtCl ４ ・nH ２ O (wherein, in each formula, n is an integer of 0 to 6, preferably 0 or 6); alcohol-modified chloroplatinic acid (a reaction product of an alcohol and chloroplatinic acid); a complex of chloroplatinic acid and an olefin; a compound in which a platinum group metal such as platinum black or palladium is supported on a support such as alumina, silica or carbon; a rhodium-olefin complex; chlorotris(triphenylphosphine)rhodium (Wilkinson's catalyst); a complex of platinum chloride, chloroplatinic acid or chloroplatinic acid salt with a vinyl group-containing siloxane; a compound in which platinum chloride is supported on polystyrene-polyethylene glycol; and the like. These curing agents may be used alone or in combination of two or more in the preparation of the surface treatment agent (X).

[0039] <Other Additives> The surface treatment agent (X) according to this embodiment may contain various additives as needed. Examples of additives include, but are not limited to, solvents, conductive compounds, surfactants, antifoaming agents, leveling agents, thickeners, antibacterial and antifungal agents, colorants, and fluororesins. These additives may be added within a range that does not impair the effects of the present invention.

[0040] The content ratio of each component in the surface treatment agent (X) is not particularly limited as long as the surface treatment coating formed from the surface treatment agent (X) has a predetermined infrared absorption spectrum, but the mass ratio of the silicone resin (A) relative to the total solid content in the surface treatment agent (X) is preferably within the range of 70.0 to 99.5 mass%, more preferably within the range of 80.0 to 99.0 mass%. The mass ratio of the silicon-containing inorganic oxide (B) relative to the total solid content in the surface treatment agent (X) is preferably within the range of 0.3 to 30.0 mass%, more preferably within the range of 0.7 to 20.0 mass%. The mass ratio of the curing agent (C) relative to the total solid content in the surface treatment agent (X) is preferably within the range of 0.005 to 0.045 mass%, more preferably within the range of 0.007 to 0.040 mass%. Furthermore, when the silicone resin (A) contains a silicone resin (A1) and a silicone resin (A2), the content ratio (by mass) thereof is not particularly limited, but the (A1):(A2) ratio is preferably within a range of 1:5 to 10:1, and more preferably within a range of 1:2 to 5:1.

[0041] <Surface Treatment Agent (Y)> The surface treatment agent (Y) according to this embodiment contains at least a compound (D) having an amino group. By using the surface treatment agent (Y), it is possible to form a base coating that improves the adhesion and scorching resistance (particularly scorching caused by proteins and lipids) of the surface treatment coating provided on the target material of the surgical electrode.

[0042] The compound (D) having an amino group is not particularly limited, but for example, the amino group may be any of a primary amino group, a secondary amino group, and a tertiary amino group, and may have two or more of these amino groups. Specific examples include amine-based curing agents; homopolymers of glycidylamine-type epoxy resins, polyethyleneimine resins, melamine resins, aromatic amine resins, etc., or copolymers containing these polymers; and silane coupling agents having an amino group. Examples of amine-based curing agents include, but are not limited to, dicyandiamide, diethylenetriamine, N-aminoethylpiperazine, metaphenylenediamine, 2-methylimidazole, and 2-ethyl-4-methylimidazole. When an amine-based curing agent is used, it is preferable to use it in combination with an epoxy resin.

[0043] The silane coupling agent having an amino group is not particularly limited as long as it has one amino group, and examples thereof include N-2-(aminoethyl)-3-aminopropyldimethylmethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyldiethylethoxysilane, N-2-(aminoethyl)-3-aminopropylethyldiethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyldimethylmethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyldiethylethoxysilane, 3-aminopropylethyldiethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, and 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine.

[0044] The solvent contained in the surface treatment agent (Y) is not particularly limited, and examples thereof include organic solvents such as alcohol, acetone, acetonitrile, benzene, cyclohexane, methyl acetate, ethyl acetate, and methyl ethyl ketone; mixtures of these organic solvents with water; and the like. The organic solvent is preferably an alcohol having 5 or less carbon atoms. In the case of a mixture of an organic solvent and water, the mass proportion of water contained is preferably less than 5 mass%, and more preferably substantially no water is contained. The surface treatment agent (Y) may also contain additives such as a conductive compound that imparts conductivity, a leveling agent that improves wettability, a film-forming aid that improves film-forming properties, an organic or inorganic crosslinking agent that forms a strong coating, an antifoaming agent that suppresses foaming, a thickener that controls viscosity, and a rust inhibitor. These additives may be incorporated within a range that does not impair the effects of the present invention.

[0045] The total content of the compound (D) having an amino group in the surface treatment agent (Y) is not particularly limited, but is preferably in the range of 0.1 mass % or more and 10 mass % or less, and more preferably in the range of 0.5 mass % or more and 5 mass % or less, relative to the total amount of the surface treatment agent (Y).

[0046] <Surgical electrode having a surface treatment coating and its manufacturing method> According to this embodiment, a surgical electrode having a surface treatment coating can be manufactured, for example, by the following method: First, a contacting step of contacting a surface treatment agent (Y) with or on the surface of a molded surgical electrode (at least a part or all of the tip portion) and a drying step of drying the surface treatment agent (Y) that has contacted the surface of the surgical electrode are carried out as necessary, thereby manufacturing a surgical electrode having a base coating.

[0047] Prior to the step of contacting the surgical electrode with the surface treatment agent (Y), the metal material may be pretreated to provide irregularities on the surface of the surgical electrode or to remove oil, dirt, or oxide film adhering to the surface of the surgical electrode. The pretreatment method is not particularly limited, and examples thereof include roughening treatments such as shot blasting, etching with a solution (such as an acidic solution or alkaline solution), polishing, plasma treatment, and corona discharge treatment; cleaning treatments such as hot water washing, solvent washing, alkaline degreasing, and pickling; oxide film removal treatments; and water washing. These treatments may be performed alone or in combination.

[0048] Various contacting methods can be used to contact the surface treatment agent (Y), and the optimal method can be selected appropriately depending on the shape of the surgical electrode, etc. Specific examples include, but are not limited to, methods such as coating using a coating device, immersion treatment, spray treatment, pouring treatment, roll coating, and bar coating. Methods for drying the surface treatment agent (Y) include, but are not limited to, methods using hot air, induction heaters, infrared rays, near-infrared rays, etc., and drying by vacuum evaporation. The drying temperature is not particularly limited, but is preferably within the range of 40 to 250°C, and more preferably within the range of 60 to 180°C. The drying time is not particularly limited and can be adjusted appropriately depending on the type of material used, the surface of the surgical electrode, or the amount of surface treatment agent (Y) attached to the surface.

[0049] The method for manufacturing a surgical electrode having a surface treatment coating according to this embodiment further includes the steps of contacting the entire surface or a portion of the surface of the surgical electrode or a base coating formed on the surgical electrode with a surface treatment agent (X), and drying the surface treatment agent (X) that has been contacted with the surgical electrode or the base coating to form a surface treatment coating. By performing these steps, a surface treatment coating or a laminated coating containing the base coating and the surface treatment coating in this order can be formed on the surgical electrode.

[0050] As a method for contacting the surface treatment agent (X), various contact methods can be used, and the most suitable method can be appropriately selected depending on the shape of the surgical electrode to be treated, etc. Specific examples include coating methods such as immersion treatment, spray treatment, pouring treatment, roll coating, and bar coating; coating methods using one or more coating devices such as a spin coater, slit coater, die coater, blade coater, and dispenser; and the like.

[0051] The drying temperature for the surface treatment agent (X) is not particularly limited, but is preferably within the range of 40 to 250°C, and more preferably within the range of 60 to 180°C. The drying method is not particularly limited, and examples include drying using hot air, an induction heater, infrared rays, near-infrared rays, etc., and drying by vacuum evaporation. The drying time is also not particularly limited, and may be adjusted appropriately depending on the type of material used, the surface of the surgical electrode, or the amount of surface treatment agent (X) adhered to the surface. For example, the drying time may be 10 minutes or more, 15 minutes or more, or 60 minutes or less, or 30 minutes or less.

[0052] Prior to the step of contacting the surgical electrode with the surface treatment agent (X), the metal material may be pretreated to provide irregularities on the surface of the surgical electrode or to remove oil, dirt, or oxide film adhering to the surface of the surgical electrode. The pretreatment method is not particularly limited, and examples include roughening treatments such as shot blasting, etching with a solution (such as an acidic solution or alkaline solution), polishing, plasma treatment, and corona discharge treatment; cleaning treatments such as hot water washing, solvent washing, alkaline degreasing, and pickling; oxide film removal treatments; and water washing. These treatments may be performed alone or in combination.

[0053] By undergoing treatment with the surface treatment agent (Y) and the surface treatment agent (X), a surface treatment coating can be formed on the surgical electrode, which includes a base coating and a surface treatment coating in this order. The portion on which the base coating is formed and the portion on which the surface treatment coating is formed may or may not be the same region. However, the base coating exists below the portion on which the surface treatment coating is formed. In one example, the base coating formed by the surface treatment agent (Y) may be formed over the entire blade portion of the distal end 11, as shown by the hatching in FIG. 7( a), or may be formed over the blade portion of the distal end 11 and a portion of the intermediate connection portion, as shown by the hatching in FIG. 7( b), or may be formed on the portion of the blade portion of the distal end 11 distal from the electrical connection portion 13 (but not on the portion close to the intermediate connection portion), as shown in FIG. 7( c).

[0054] In one example, the surface treatment coating formed from the surface treatment agent (X) is formed over the entire flat surface of the tip (the upper and lower surfaces of the blade portion), as shown by the dotted pattern in Figure 8(a), but is not formed on the side surface of the blade portion (surfaces other than the flat surface), although a surface treatment coating may be formed on the longitudinal side surface of the blade portion in a region extending 2 mm from the electrical connection portion 13 to the end. In another example, as shown by the dotted pattern in Figure 8(b), no surface treatment coating is formed on the side surface or the ends of the upper and lower surfaces of the blade portion. In this way, by not forming a surface treatment coating on the side surface or the ends of the upper and lower surfaces (portions distal from the electrical connection portion 13), particularly the corners, high frequency can be sufficiently emitted from the portion of the tip that may come into contact with biological tissue, i.e., the discharge portion (hereinafter referred to as the "discharge portion"), thereby ensuring good incision ability of the surgical electrode instrument. When forming a surface treatment coating on the edges of the side and upper and lower surfaces, particularly on the corners, it is preferable to make the coating thickness thin (for example, 10 μm or less, preferably 5 μm or less, more preferably 2 μm or less), which allows sufficient high frequency to be emitted from the discharge part, which is a location that can come close to biological tissue, and prevents a decrease in incision ability.

[0055] The amount of the coating made of the surface treatment agent (Y) on the tip portion (the blade portion in the case of a blade-type surgical electrode) having the surface treatment coating is not particularly limited, but is preferably 0.1 mg / m ２ 50mg / m or more ２ It is preferable that the concentration is within the range of 1 mg / m ２ 40mg / m or more ２ It is more preferable that the thickness is within the following range: When the base coating is formed using a silane coupling agent having an amino group, SiO ２ It is preferable that the converted mass is within the above range. The coating weight of the base coating can be determined by measuring the coating weight on a predetermined area of ​​the metal material. When the base coating is formed from a silane coupling agent having an amino group, it can be analyzed by fluorescent X-ray spectroscopy, and the SiO ２ The mass converted into the weight of the coating can be calculated and the amount of coating per unit area can be determined.

[0056] Furthermore, the total thickness of the base coating (surface treatment agent (Y)) and the surface treatment coating (surface treatment agent (X)) formed on the tip portion (the blade portion in the case of a blade-type surgical electrode) is preferably within a range of 10 μm or more and 400 μm or less, more preferably within a range of 20 μm or more and 300 μm or less, even more preferably within a range of 30 μm or more and 200 μm or less, and particularly preferably within a range of 50 μm or more and 150 μm or less.

[0057] The effects of the present invention will be specifically demonstrated below by way of examples, but the following examples are not intended to limit the scope of the present invention in any way.

[0058] (1) Preparation of Surgical Electrode A blade-type surgical electrode was prepared, in which the tip 11 of the surgical electrode shown in Figure 1 is plate-shaped. The materials and blade size of the prepared surgical electrode are shown below. The surface roughness (arithmetic mean roughness: Ra) of the blade was measured using a three-dimensional surface roughness measuring instrument (Tokyo Seimitsu Co., Ltd., Model Surfcom 570A). The measurement was performed by scanning 2.0 mm at a speed of 0.3 mm / s. (Z1) Material of surgical electrode: Stainless steel SUS304 Ra = 0.14 μm Size of blade part: Thickness 0.3 mm, Length 17.0 mm, Width 2.5 mm (Z2) Material of surgical electrode: Stainless steel SUS316L Ra = 0.14 μm Size of blade part: Thickness 0.3 mm, Length 17.0 mm, Width 2.5 mm (Z3) Material of surgical electrode: Tungsten steel Ra = 0.14 μm Size of blade part: Thickness 0.3 mm, Length 17.0 mm, Width 2.5 mm

[0059] The blade of the surgical electrode was immersed in 2-propanol (first-grade, manufactured by Junsei Chemical Co., Ltd.) and ultrasonically treated for 10 minutes to remove oil and dirt from the surface. The blade was then dried at 120°C for 10 minutes to remove any adhering 2-propanol.

[0060] (2) Preparation of Surface Treatment Agents Surface treatment agents (X) were prepared by mixing the following silicone resin (A), silicon-containing inorganic oxide (B), and curing agent (C) with xylene to give solid mass concentrations of 15 to 40%, to prepare surface treatment agents X1 to X22. In Table 1, the mass percentages of "silicone resin (A)," "silicon-containing inorganic oxide (B)," and "curing agent (C)" respectively represent the mass proportion of the solid content of each component relative to the total solid content. Furthermore, the ratio of A1:A2 in surface treatment agents X2 to X17 represents the solid mass proportion.

[0061] [Silicone resin (A)] A1: A mixture of polydimethylsiloxane having dimethylvinylsiloxane groups at both ends of the molecular chain and a methylhydrogensiloxane-dimethylsiloxane copolymer having trimethylsilyl groups at both ends of the molecular chain (T units) A2: A two-component addition liquid silicone rubber having vinyl terminal groups (D units) A3: A one-component curing oligomer (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KR-400) (T units) A4: A methyl / phenyl-based silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KR-282) (D units and T units) A5: A methyl / phenyl-based silicone resin (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KR-300) (D units and T units) [Silicon-containing inorganic oxide (B)] B1: Amorphous silica (average particle size 12 nm) B2: A crystalline silica (average particle size 12 nm) B3: Sodium silicate (average particle size 50 nm) B4: Calcium silicate (average particle size 40 nm) B5: Magnesium silicate (average particle size 30 nm) B6: Zircon (average particle size 1 μm) [Curing agent (C)] C1: Tetrachloroplatinic (II) acid (manufactured by Shin-Etsu Chemical Co., Ltd., product name = D-168) C2: Titanium butoxide (manufactured by Shin-Etsu Silicones Co., Ltd., product name = D-20) C3: Titanium acetylacetonate (manufactured by Matsumoto Fine Chemical Co., Ltd., product name = TC-100) C4: Platinum catalyst (manufactured by Arakawa Chemical Industries, Ltd., product name = CATA93B)

[0062] For the surface treatment agent (Y), D1 or D2 was used as the following compound (D) having an amino group, and solutions (Y1, Y2) were prepared by mixing D1 or D2 in ethanol so that the solid mass concentration of D1 or D2 was 1.0%. [Compound (D) having an amino group] D1: 3-aminopropyltriethoxysilane D2: N-(2-aminoethyl)-3-aminopropyltrimethoxysilane

[0063]

[0064] (3) Manufacturing of the tip portion 11 having a surface treatment coating Various surface treatment agents (X) shown in Table 2 were applied to the flat surface (both sides) of the tip portion 11 using the following dispenser, and dried at a drying temperature for 30 minutes to obtain surgical electrodes having a surface treatment coating of a predetermined thickness (see Table 2) for Examples 1 to 27 and Comparative Examples 1 to 4. Dispenser (desktop robot): manufactured by Musashi Engineering, product names: ML-808GX, SM4000MEGAX-3A-SS

[0065] The same treatment was also carried out on the flat surface (both sides) of the tip 11, which had a base coating as needed. Regarding the base coating, the blade portion, from which oil and dirt had been removed, was immersed in the surface treatment agent (Y). After immersion, the blade portion was dried at 120°C for 10 minutes to obtain a surgical electrode with a base coating. When base coatings were formed using Y1 and Y2, they were analyzed by X-ray fluorescence spectroscopy, and the intensity of Si was used to determine whether the SiO ２ The mass converted into 100g was calculated to determine the amount of coating per unit area.

[0066]

[0067] (4) FT-IR measurement (β Ａ / α Ａ , γ Ａ / α Ａ , γ Ａ / β Ａ The analysis was carried out by ATR, a type of infrared spectroscopy. The equipment used was a Perkin Elmer FT-IR (Spectrum Two) equipped with an accessory for ATR measurement (GladiATR). ＴＭ The specimen was stainless steel treated with surface treatment agent (X), and the specimen surface was pressed against the measurement area for measurement. After the measurement, ATR correction and baseline correction were performed, and the 4000 cm －１ The absorbance of the peak α was corrected to be 0. Ａ ) with respect to the absorbance of the peak β (β Ａ ) ratio (β Ａ / α Ａ The value of the peak intensity (α) of the peak α was the average value of three measurements. Ａ ) with respect to the peak intensity of the peak γ (γＡ ) ratio (γ Ａ / α Ａ ) value of the peak β and the peak intensity (β Ａ ) with respect to the peak intensity of the peak γ (γ Ａ ) ratio (γ Ａ / β Ａ The values ​​of ) were also measured three times and averaged. The obtained values ​​are shown in Table 3.

[0068] (5) Evaluation Test (5-1) Scorching Resistance A (Assuming a Large Amount of Blood) Two drops (1 drop: 3 μl) of pig blood (Tokyo Shibaura Organ Co., Ltd.) were dropped onto a surgical electrode, and three cycles of heating at 350°C / 1 min → cooling at room temperature / 1 min were performed in a muffle furnace. After the surgical electrode was cooled at room temperature, the blood adhering to the coating was wiped dry with a Kimwipe. Two drops of pig blood were again dropped onto the coating, and three cycles of heating at 350°C / 1 min → cooling at room temperature / 1 min were performed. Finally, the surgical electrode was cooled to room temperature and then wiped dry with a Kimwipe. The remaining ratio of the blood scorched area on the surgical electrode after the final dry wipe to the blood scorched area on the surgical electrode after the second cycle (three sets) was determined, and scorching resistance was evaluated according to the following criteria. The results are shown in Table 3. S: Residual rate less than 1% A: Residual rate 1% to less than 15% B: Residual rate 15% to less than 30% C: Residual rate 30% to less than 45% D: Residual rate 45% or more or peeling of coating is present

[0069] (5-2) Anti-sticking property B (assuming a case with a high protein and lipid content) The surgical electrodes of Examples 1 to 27 and Comparative Examples 1 to 4 were electrically connected to the electrosurgical instrument body shown below. Furthermore, the return electrode electrically connected to the electrosurgical instrument body was attached to a stainless steel container containing pork liver. <Electrosurgical instrument body (high frequency device and control pencil)> High frequency device: Excalibur Plus PC Medical device approval number 20700BZY01171 Control pencil: Disposable control pencil manufactured by Japan Medical Next Co., Ltd. Medical device approval number: 20300BZY01003000

[0070] The electrosurgical instrument was operated in pure incision mode (30 W output power), and the blade was inserted perpendicular to the surface of the pork liver at a 45° angle. At a depth of 12 mm, the blade was moved 60 mm parallel to the surface at a speed of 20 mm / s to make an incision. After repeating the incision twice, the surgical electrode was allowed to cool to room temperature. The area to be evaluated was then wiped once with a gauze between fingers. The coating on the area to be evaluated was then visually inspected, and its resistance to scorching was evaluated according to the evaluation criteria. The results are shown in Table 3. S: Less than 1% of the area remained scorched. A: 1% to less than 5% of the area remained scorched. B: 5% to less than 15% of the area remained scorched. C: 15% or more of the area remained scorched.

[0071] (5-3) Adhesion The electrosurgical instrument was operated in pure incision mode (output: 30 W), and the blade was inserted perpendicularly at a 45° angle to the surface of the pork liver. At a depth of 12 mm, the blade was moved 60 mm parallel to the surface of the pork liver at a speed of 20 mm / s to make an incision. After repeating the incision twice, the surgical electrode was allowed to cool to room temperature. The evaluation area was then wiped once using gauze between fingers. The coating on the evaluation area was then visually observed, and the anti-sticking properties were evaluated according to the evaluation criteria. The results are shown in Table 3. S: Coating peeling area of ​​the evaluation area was less than 1%. A: Coating peeling area of ​​the evaluation area was 1% to less than 5%. B: Coating peeling area of ​​the evaluation area was 5% to less than 15%. C: Coating peeling area of ​​the evaluation area was 15% or more.

[0072]

[0073] Although the present invention will be described in detail with reference to specific examples, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention.

[0074] 10, 20, 30, 40, 60 Surgical electrode 11, 21, 31, 41, 61 Tip portion 12 Middle portion 13, 23, 33, 43 Electrical connection portion 14, 24, 34, 44 Coating

Claims

1. A surgical electrode of an electrosurgical instrument used in surgery on living tissue, the surgical electrode having a tip capable of emitting high frequency waves, the tip having a surface treatment coating, and the surface treatment coating having an infrared absorption spectrum of 950 cm －１ From 1060cm －１ and a peak (α) in the range of 720 cm －１ From 830 cm －１ and a peak in the range of 450 cm －１ From 495 cm －１ and the peak intensity (α Ａ ) with respect to the peak intensity of the peak β (β Ａ ) ratio (β Ａ / α Ａ ) is in the range of 0.770 to 1.

040.

2. The surgical electrode according to claim 1, wherein the surface treatment coating comprises a silicone resin (A), and the silicone resin (A) comprises a structural unit consisting of D units and a structural unit consisting of T units.

3. The surgical electrode according to claim 2, wherein the surface treatment coating comprises an inorganic oxide (B) containing silicon.

4. A surgical electrode according to any one of claims 1 to 3, wherein the tip portion further comprises a base coating formed from a surface treatment agent (Y) containing a compound (D) having an amino group.

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