JPH0423537Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a conductive sheet material for electric scalpels, and more specifically, it has excellent compatibility with living organisms to obtain a uniform current density, and is flexible. The present invention relates to a novel conductive sheet material for electric scalpels that does not harm living organisms and prevents a drop in body temperature during surgery because it has no heat dissipation effect.

[Prior art] Conductive sheet materials used in surgical operations, etc.
By passing an electric current through the living body between the sheet material and the electric scalpel, incisions in the living body and coagulation of body fluids are performed. Conventionally, metal foil such as aluminum foil, metal foil and knitted fabric, etc. Laminated sheets with adhesives or wet sheets using conductive liquids or jelly have been used.

Furthermore, as a product considered to be most similar to the present invention, a return electrode plate made of a woven fabric using carbon fibers or metal fibers is proposed in Japanese Patent Application Laid-open No. 123591/1983.

[Problems to be solved by the invention] The above-mentioned products using metal foil have the disadvantage that they are not compatible with the living body due to the rigidity of the metal foil, and as a result, it is not possible to obtain a uniform current distribution, which is essential for surgery. Moreover, since the metal foil removes body heat from the living body and radiates heat, there is a risk that children, in particular, may lose their physical strength during surgery.

Conductive wet sheets are used by impregnating a sponge or cotton-like flexible sheet with high viscosity liquid or jelly, so they are more compatible with living organisms than metal foils and have a more uniform current distribution. However, these wet sheets tend to dry out when used for a long time, resulting in the risk of burning living organisms, and there are also problems in that the current density changes over time. .

The textile return electrode proposed in Japanese Patent Application Laid-open No. 53-123591 is considered to be an excellent material capable of solving the above problems. However, although the return electrode made of this textile has a suitable fit on relatively flat parts of the living body, such as the back and thighs,
It is less suitable for children's bodies with few flat areas and complex parts, and there are problems such as wrinkles similar to metal foil, resulting in uneven current distribution, and fibers unraveling at cut parts of the fabric. Moreover, since carbon fibers and metal fibers are used, there is a risk that these fibers may irritate or damage living organisms, so that they are not necessarily satisfactory conductive sheet materials.

The present invention overcomes these conventional drawbacks and relates to a conductive sheet material for electric scalpels that is highly compatible with living organisms, flexible, and extremely safe.

[Means for solving the problem] The present invention contains at least 10% by weight of conductive fibers with a specific resistance of 10 ^-1 Ω・cm or less, and has a surface specific resistance of
Regarding a conductive sheet material for an electric scalpel made of a hydroentangled nonwoven fabric of 10 ³ Ω・cm or less, more preferably, it contains 20 to 50% by weight of heat-fusible fibers to further improve the mechanical properties due to entanglement. The present invention relates to a conductive sheet material for an electric scalpel having a reinforced structure.

[Function] The present invention was completed after discovering that a hydroentangled nonwoven fabric with a surface resistivity of 10 ³ Ω・cm or less has optimal performance as a conductive sheet material for an electric scalpel, and its structure is described below. and its operation will be explained in detail with reference to the drawings.

The surface resistivity of conductive sheet material for electric scalpels is conventionally 10 ² Ω・cm or less, preferably 10 ⁰ Ω・cm.
The following materials have been considered suitable. However, the conductive sheet material of the present invention has a structure in which each fiber constituting the sheet material is intricately and three-dimensionally entangled by water jetting, so it is extremely uniform both in the surface direction and the thickness direction of the sheet. Because it is conductive and does not substantially use materials that inhibit conductivity such as adhesives,
100% of the electrical properties of conductive fibers can be utilized. Therefore, in the present invention, even a sheet material with a surface resistivity of about 10 ³ Ω·cm, which is higher than conventional ones, can be used satisfactorily. However, if the surface resistivity of the conductive sheet material 1 exceeds 10 ³ Ω·cm, it is not preferable because problems such as heat generation occur as with conventional materials.

The specific resistance used in this invention to obtain conductivity is
The conductive fibers 2 having a diameter of 10 ^-1 Ω・cm or less form the skeleton of the conductive sheet material 1, and are entangled either alone or with other synthetic fibers such as heat-fusible fibers 5 by the action of water flow. As a result, a conductive hydroentangled nonwoven fabric is formed, and it is provided with mechanical properties such as tensile strength or tear strength, and also has excellent adaptability to the living body 7 and flexibility.

These conductive fibers 2 have a specific resistance of 10 ^-2
Materials with a resistivity of 10 -1 to 10 ^-1 Ω・cm include general-purpose synthetic fibers such as acrylic fibers that are chemically treated with metal compounds such as copper sulfide by dyeing methods, and materials with a specific resistance of 10 ^-4 to 10 ^-2 Ω.・CM materials include those in which metallic materials such as nickel are plated or vapor-deposited on the surface of the fibers, and these surface-metalized synthetic fibers provide conductivity to hydroentangled nonwoven fabrics and increase single fiber strength. It is suitable as a fiber material to be used in the present invention because it has excellent properties such that a high-strength sheet can be obtained. Also, for these fibers, the fiber length is 25
Staple fibers with a diameter of 150 mm to 150 mm and a fineness of 0.5 to 15 deniers, preferably 6 deniers or less, are desirable because the strongest entanglement strength and extremely soft texture can be obtained by water jetting.

When using conductive fibers such as carbon fibers with a specific resistance exceeding 10 ^-1 Ω・cm, if the blending ratio of these conductive fibers is small, the resulting hydroentangled nonwoven fabric will have a predetermined surface resistivity. is not obtained, making it unsuitable as a sheet material for electric scalpels.Also, when the blending ratio is increased, even if the desired conductivity is obtained, it is inferior in compatibility with living organisms and flexibility. This method is unsuitable because it may injure living organisms and the strength of entanglement caused by jetting water is low.

On the other hand, if metal fibers with excellent conductivity with a specific resistance of 10 ^-4 Ω・cm or less are used, a sheet material with excellent conductivity can be obtained, but these metal fibers have a small fiber diameter. It is difficult to obtain fibers with crimps and crimps, resulting in poor productivity, poorer hydroentanglement properties than carbon fibers, and high risk of damaging living organisms, which is not preferable.

The above-mentioned conductive fibers preferably contain at least 10% by weight or more, preferably 20% by weight or more of the total fibers constituting the hydroentangled nonwoven fabric used in the present invention, and the conductive fibers are less than 10% by weight. In this case, the surface resistivity of the sheet material exceeds 10 ³ Ω·cm, which is inappropriate.

Next, to briefly explain the hydroentanglement technology used in the present invention, for the hydroentanglement technology, it is sufficient to apply the known technology known, for example, in US Pat. No. 3,088,859. A water stream is sprayed onto the fiber web containing at least 10% by weight through a large number of fine orifices to entangle each fiber. Through the entanglement treatment using these water jets, each fiber is entangled in a complex and three-dimensional manner, and as a result, the nonwoven fabric has extremely uniform conductive properties throughout, and has mechanical properties such as tensile strength and tear strength. A sheet material with excellent physical properties can be obtained.

Next, to explain terminal 3, terminal 3 is:
Together with the electric scalpel 6, it is connected to a power source via a cord, and by passing a current between the terminal 3 and the electric scalpel 6 via the living body 7, the living body is incised or the body fluid is coagulated. Therefore, the terminal 3 is not particularly limited and may be any material as long as it is made of a conductive material and has a structure that allows easy connection. The sheet material of the present invention utilizes hydroentanglement means, so if the terminals 3 are made of a porous material such as metal mesh or punch metal, the conductive fibers 2 and the terminals 3 will be firmly entangled due to hydroentanglement. Since it is bonded together, there is no need for special terminal installation methods such as gluing or welding, and there is no risk of short circuits due to poor bonding, so an extremely safe and reliable conductive sheet material can be obtained, making it the most suitable material. It can be said that it belongs to.

The conductive sheet material for electric scalpels of the present invention has sufficient mechanical and electrical properties to withstand surgery, etc. by utilizing the above-mentioned hydroentanglement, but it also has sufficient strength and shape retention properties of the sheet material. In order to increase the heat-fusible fiber 5, it is recommended to mix 20 to 50% by weight of the total constituent fibers. The heat-fusible fibers 5 have the effect of further improving the mechanical properties of the hydroentangled nonwoven fabric, preventing the sheet material from slipping during surgery, increasing safety, and the conductive adhesive described below. It also has the effect of increasing the dimensional safety of the sheet and greatly improving workability in the process of forming the agent layer.

These heat-fusible fibers may be undrawn polyester, polyolefin, modified polyamide, modified polyester, or composite fibers thereof, but if excessive heat-fusion occurs, the flexibility of the nonwoven fabric and This prevents it from adapting to the living body,
The blending rate of these heat-fusible fibers should not exceed 50% by weight, and the heat-fusion treatment should be carried out at a low temperature of about 170°C or less, and/or about 1 Kg/ ^cm2 , preferably 0.5 Kg/cm2. ^cm2
It is desirable to perform this under low pressure conditions such as the following.

Furthermore, as a means of increasing the adhesion of the conductive sheet material 1 to the living body 7 during surgery and making the current distribution uniform, it is also an effective means to provide a conductive adhesive layer 4 on one surface of the sheet material.

The conductive adhesive layer contains at least 75% by weight of the above-mentioned surface metallized synthetic fibers and has a basis weight of 30g/m ²
The method of laminating the following thin non-woven fabric impregnated with a conductive adhesive 4 with the hydroentangled non-woven fabric, or the method of laminating silver in a well-known adhesive such as acrylic
Any method may be used, such as applying a dispersed fine powder of copper, nickel, etc. to the hydroentangled nonwoven fabric. In addition, when the hydroentangled nonwoven fabric mentioned above contains 75% by weight or more of conductive fibers, or has a layered structure in which the surface layer contains 75% by weight or more of conductive fibers, the pressure-sensitive adhesive may be used. Even without making the adhesive conductive, it is possible to obtain a sufficiently conductive adhesive layer simply by impregnating the surface layer with the adhesive, which is much more advantageous than making the adhesive conductive.

With the above structure, the conductive sheet material for electric scalpels of the present invention has far superior compatibility with living organisms than conventional ones, and as a result, an extremely uniform current distribution can be obtained. Moreover, it is an extremely high-quality sheet material that is not only electrically safe but also does not harm living organisms or steal body heat. Needless to say, it is easily possible to mix any fibers other than conductive fibers, or to insert a reinforcing sheet layer, such as a knitted fabric, if special characteristics are required. However, the present invention does not exclude these auxiliary means.

Hereinafter, the conductive sheet material of the present invention will be explained in more detail with reference to Examples.

[Example] As a conductive fiber, acrylonitrile fiber (2 denier, 51 mm) chemically treated using copper sulfide
length, specific resistance 1.3×10 ^-2 Ω・cm) 20% by weight, undrawn polyester fiber (2 denier, 38mm length) 40% by weight as heat-fusible fiber, polyester fiber (1.5
denier, 44mm length) and 40% by weight.
A web with a basis weight of 45 g/m ² formed by the card method and 100% of the above-mentioned conductive acrylonitrile fiber (2 denier, 51 mm length, specific resistance 1.3 × 10 ^-2 Ω・cm)
After laminating a web with a fabric weight of 15 g/ ^m2 and inserting a stainless steel punch metal between these layers as a terminal, a water pressure of 80 kg was applied using a nozzle with an orifice diameter of 0.15 mm and a number of orifices of 1000/m. /
cm ² and a water flow rate of 120/min to entangle each fiber three-dimensionally, and then dried at a temperature of 100°C to form a conductive material with a basis weight of 60 g/m ² and a thickness of 0.6 mm. A hydroentangled nonwoven fabric was obtained.

The obtained nonwoven fabric was plasticized and crimped with unstretched polyester fibers at 150°C and a pressure and temperature of 0.3 Kg/cm ² using a roller press machine to give a thickness of 0.25 cm.
mm sheet.

Next, on the surface of the layer made of 100% conductive fibers,
While pressing the hot melt adhesive onto the sheet surface,
A conductive sheet material for an electric scalpel according to the present invention was obtained by uniformly applying 30 g/m ² .

The surface resistivity of the obtained sheet material was approximately 2.3×10Ω・cm on the adhesive side surface and approximately 8×10 ² on the opposite surface.
Ω·cm, substantially no unevenness in resistivity distribution was observed at any position, and the tensile strength was sufficiently high at 2 kg or more per 1 cm width.

Furthermore, this sheet material had a very soft texture, was well compatible with living organisms, and was of high quality with no risk of damaging living organisms.

[Effects of the invention] The conductive sheet material for electric scalpels according to the invention has the following effects:
Since it is a flexible hydroentangled nonwoven fabric, the performance of conductive fibers can be utilized most efficiently.

Since these conductive fibers are usually expensive, their economical effects are very high.

In addition, compared to conventional textiles, the sheet material of the present invention is made of non-woven fabric, so even when cut into any shape or size, no thread layers are generated, and as a result, there is no need for surgery. Since it can be applied to the optimal location and in the optimal shape, it does not interfere with surgery at all and is much more useful than conventional methods.

Moreover, since entanglement is mainly used as the bonding means between the fibers that make up the nonwoven fabric,
No harmful substances are emitted from the sheet material, making it extremely safe.

Therefore, the conductive sheet material for an electric scalpel of the present invention not only provides compatibility with the living body and uniform current distribution, which are necessary as an electrode sheet for an electric scalpel, but also has economic efficiency, safety, and This is an epoch-making product that significantly innovates over conventional products in terms of workability and other aspects.

[Brief explanation of the drawing]

FIG. 1 is an enlarged sectional view showing an example of the conductive sheet material for an electric scalpel according to the present invention, and FIG. 2 is a schematic diagram showing an example of its use. The numbers in the figure are 1... conductive sheet material, 2...
...Conductive fiber, 3...Terminal, 4...Conductive adhesive, 5...Heat-fusible fiber, 6...Electric scalpel, 7...
...Biological body, 8...Power source.

Claims (1)

[Claims for Utility Model Registration] (1) Contains at least 10% by weight of conductive fibers with a specific resistance of 10 ^-1 Ω・cm or less, and has a surface specific resistance of 10 ³
A conductive sheet material for an electric scalpel, which is made of a hydroentangled nonwoven fabric of Ω·cm or less, and has a structure in which terminals are provided at arbitrary positions on the nonwoven fabric. (2) The conductive sheet material for an electric scalpel according to claim 1, wherein the terminal is a porous metal material. (3) The conductive sheet material for an electric scalpel according to claim 1, wherein 20 to 50% by weight of the fibers constituting the hydroentangled nonwoven fabric are heat-fusible fibers. (4) The conductive fiber has a fiber length of 25 to 150 mm and a fineness of 0.5.
The conductive sheet material for an electric scalpel according to claim 1, which is a surface metallized synthetic fiber having a denier of 15 to 15 denier and a specific resistance of 10 ^-3 to 10 ^-1 Ω·cm.