JP2012094523A - Plasma generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma generating device for generating plasma in a living body.SOLUTION: A plasma generating device comprises: a first electrode for generating plasma which includes a conductive member covered with an insulator or a dielectric; a container 110 made of an insulator which houses the first electrode, and which is inserted in a living body 100 to be interposed between the first electrode and the living body; a second electrode 120 electrically connected to the living body 100; and a power supply 40 which applies AC voltage or pulse voltage between the first electrode and the second electrode 120.

Description

  The present invention relates to a plasma generation method and a plasma generation apparatus, and more particularly to a plasma generation method and a plasma generation apparatus that generate plasma in a space adjacent to a liquid or in a living body.

  2. Description of the Related Art Conventionally, a method using plasma to perform cleaning, etching, film formation, and the like is known.

  In Patent Document 1, in order to perform stable discharge in the atmosphere without using helium gas, a reaction tube that supplies a reaction gas, and first and second elements that are disposed opposite to each other across the reaction tube and act on the reaction gas. There is disclosed a plasma processing apparatus that supplies a high frequency power to first and second electrodes to excite a reactive gas and processes a substrate to be processed with generated plasma.

  In Patent Document 2, in order to generate a uniform discharge plasma under a pressure in the vicinity of atmospheric pressure regardless of the gas atmosphere at the time of processing, a solid dielectric is disposed on at least one facing surface of the counter electrode, A technique for applying a pulsed electric field in between is disclosed.

  The technique disclosed in Patent Document 1 is a technique in which a reaction gas flowing in a reaction tube is converted into plasma, and the plasma is injected from the reaction tube to an object to be processed. Surface treatment is performed on an object to be treated placed on a two-electrode plate, and both are surface treatment techniques based on a relatively large apparatus.

JP 2002-184759 A JP-A-10-154598

Edited by Toyoaki Omori: Electromagnetism and Biology (1987) Nikkan Kogyo Shimbun

  However, the conventional plasma generator is based on the premise that plasma is generated in the atmosphere or under reduced pressure, and there has been no device that generates plasma in the vicinity of the place where the liquid exists. Similarly, there has never been an apparatus for generating plasma in a living body in which liquid is a main constituent.

  The present invention has been made in view of this point, and an object of the present invention is to provide a method and apparatus for generating plasma in a space adjacent to a liquid or in a living body.

  In order to achieve the above object, the first plasma generation method of the present invention uses a liquid as the outer surface of a container in which a first electrode having a conductive member covered with an insulator or a dielectric is stored. A step of contacting, a step of electrically connecting a second electrode to the liquid, and applying an alternating voltage or a pulse voltage between the first electrode and the second electrode, And a plasma generation step of generating plasma in the internal space of the container around the electrode. By having such a configuration, an electric field is formed between the liquid and the first electrode, and plasma is easily generated in the container. Here, the first electrode stored in the container is not in contact with the liquid. Electrically connecting the second electrode to the liquid means that the second electrode is in direct contact with the liquid, or that both the second electrode and the liquid are grounded. It means to let the flow.

  The second plasma generation method of the present invention is a plasma generation method for generating plasma in a living body, and a container in which a first electrode having a conductive member covered with an insulator or a dielectric is stored. An AC voltage or a pulse voltage is applied between the first electrode and the second electrode, and a step of electrically connecting the second electrode to the living body. And a plasma generation step of generating plasma in the internal space of the container around the first electrode. By having such a configuration, an electric field is formed between the living body and the first electrode, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the living body.

  In a preferred embodiment, in the connecting step, the second electrode is brought into contact with the surface of the living body.

  In a preferred embodiment, in the connecting step, the second electrode is inserted into the living body.

  In a preferred embodiment, the second electrode is a ground electrode, and the biological surface is grounded in the connection step.

  The third plasma generation method of the present invention includes a step of bringing an outer surface of a container in which a first electrode including a conductive member covered with an insulator or a dielectric is stored into contact with a liquid, and a second electrode Contacting the liquid via an intervening member made of an insulator or a dielectric, and applying an AC voltage or a pulse voltage between the first electrode and the second electrode, And a plasma generation step of generating plasma in the internal space of the container around the electrode. By having such a configuration, an electric field is formed between the liquid and the first electrode by dielectric polarization, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the liquid.

  A fourth plasma generation method of the present invention is a plasma generation method for generating plasma in a space adjacent to a grounded liquid, and the first plasma generation method includes a conductive member covered with an insulator or a dielectric. A step of bringing the outer surface of the container in which the electrode is stored into contact with the liquid, a step of grounding the second electrode via an interposed member made of an insulator or a dielectric, the first electrode and the second electrode And a plasma generation step of generating a plasma in the inner space of the container around the first electrode by applying an alternating voltage or a pulse voltage between the first electrode and the second electrode. By having such a configuration, an electric field is formed between the liquid and the first electrode by dielectric polarization, and plasma is easily generated in the container. That the second electrode is grounded via an interposed member made of an insulator or a dielectric means that the second electrode is grounded when it is assumed that the interposed member has conductivity. The first electrode stored in the container is not in contact with the liquid.

  A fifth plasma generation method of the present invention is a plasma generation method for generating plasma in a living body, and a container in which a first electrode including a conductive member covered with an insulator or a dielectric is stored. Between the first electrode and the second electrode, the step of bringing the second electrode into contact with the living body via an intervening member made of an insulator or dielectric, And a plasma generation step of generating plasma in the internal space of the container around the first electrode by applying an AC voltage or a pulse voltage. By having such a configuration, an electric field is formed between the living body and the first electrode by dielectric polarization, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the living body.

  A sixth plasma generation method of the present invention is a plasma generation method for generating plasma in a living body, and a container in which a first electrode including a conductive member covered with an insulator or a dielectric is stored. , A step of grounding the living body, a step of grounding the second electrode via an intervening member made of an insulator or a dielectric, the first electrode and the second And a plasma generation step of generating plasma in the internal space of the container around the first electrode by applying an alternating voltage or a pulse voltage between the electrode and the electrode. By having such a configuration, an electric field is formed between the living body and the first electrode by dielectric polarization, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the living body.

  In a preferred embodiment, the conductive member is a linear member, and the container is a thin tube.

  In a preferred embodiment, the container has translucency.

  In a preferred embodiment, in the plasma generation step, a predetermined gas is allowed to flow into or sealed in the container.

  In a preferred embodiment, the method further includes a step of releasing the predetermined gas chemically changed by the generation of the plasma out of the container.

  In a preferred embodiment, the liquid has an electric conductivity of 0.055 μS / cm or more or a relative dielectric constant of 60 or more. The electrical conductivity of ultrapure water is 0.055 μS / cm.

  A first plasma generator of the present invention is a plasma generator for generating plasma in a space adjacent to a liquid, and includes a conductive member covered with an insulator or a dielectric, and generates plasma. A first electrode; a container that houses the first electrode and whose outer surface is in contact with the liquid; a second electrode that is electrically connected to the liquid; the first electrode and the second electrode; And a power source for applying an alternating voltage or a pulse voltage. Since it has such a configuration, an electric field is formed between the liquid and the first electrode, and plasma is easily generated in a container which is a space adjacent to the liquid. The first electrode stored in the container is not in contact with the liquid. Electrically connecting the second electrode to the liquid means that the second electrode is in direct contact with the liquid, or that both the second electrode and the liquid are grounded. It means to let the flow.

  A second plasma generator of the present invention is a plasma generator for generating plasma in a living body, and includes a conductive member covered with an insulator or a dielectric, and a first electrode for generating plasma. An AC between the first electrode and the second electrode; and a container inserted into the living body, a second electrode electrically connected to the living body, and the first electrode and the second electrode. And a power supply for applying a voltage or a pulse voltage. Since it has such a structure, an electric field is formed between the living body and the first electrode, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the living body.

  A third plasma generation apparatus of the present invention is a plasma generation apparatus that generates plasma in a space adjacent to a liquid, and includes a conductive member covered with an insulator or a dielectric, and generates plasma. A first electrode; a container that houses the first electrode and whose outer surface is in contact with the liquid; a second electrode that is in contact with the liquid through an intermediate member made of an insulator or a dielectric; and the first electrode And a power source for applying an AC voltage or a pulse voltage between the second electrode and the second electrode. Since it has such a configuration, an electric field is formed between the liquid and the first electrode by dielectric polarization, and plasma is easily generated in a container which is a space adjacent to the liquid. The first electrode stored in the container is not in contact with the liquid.

  A fourth plasma generation apparatus of the present invention is a plasma generation apparatus that generates plasma in a space adjacent to a grounded liquid, and includes a conductive member covered with an insulator or a dielectric. A first electrode for generating the first electrode, a container in which the first electrode is stored and whose outer surface is in contact with the liquid, a second electrode that is grounded via an intermediate member made of an insulator or a dielectric, A power supply for applying an AC voltage or a pulse voltage is provided between the first electrode and the second electrode. Since it has such a configuration, an electric field is formed between the liquid and the first electrode by dielectric polarization, and plasma is easily generated in a container which is a space adjacent to the liquid. The first electrode stored in the container is not in contact with the liquid.

  A fifth plasma generator of the present invention is a plasma generator for generating plasma in a living body, and includes a conductive member covered with an insulator or a dielectric, and a first electrode for generating plasma. A container that stores the first electrode and is inserted into the living body, a second electrode that contacts the living body via an interposed member made of an insulator or a dielectric, and the first electrode, And a power source for applying an AC voltage or a pulse voltage between the second electrode and the second electrode. Since it has such a configuration, an electric field is formed between the living body and the first electrode by dielectric polarization, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the living body.

  A sixth plasma generation apparatus of the present invention is a plasma generation apparatus that generates plasma in a living body that is grounded, and includes a conductive member that is covered with an insulator or a dielectric, and generates plasma. A first electrode; a container that stores the first electrode; and is inserted into the living body; a second electrode that is grounded via an intervening member made of an insulator or a dielectric; and the first electrode A power source for applying an alternating voltage or a pulse voltage between the electrode and the second electrode; Since it has such a configuration, an electric field is formed between the living body and the first electrode by dielectric polarization, and plasma is easily generated in the container. The first electrode stored in the container is not in contact with the living body.

  In a preferred embodiment, the conductive member is a linear member, and the container is a thin tube.

  In a preferred embodiment, the container has translucency.

  In a preferred embodiment, a gas inflow member for allowing a predetermined gas to flow into the container is further provided.

  In a preferred embodiment, a predetermined gas is sealed in the container.

  In a preferred embodiment, at least a part of the container is made of a permeable membrane that allows the predetermined gas to selectively pass a substance chemically changed by the plasma.

  Since the first electrode is placed in the container and the outer wall of the container is in contact with the liquid so that an electric current flows in the liquid in some form, plasma can be easily generated in the liquid adjacent space. Similarly, plasma can be easily generated in the living body.

1 is a schematic diagram of a plasma generator according to Embodiment 1. FIG. It is sectional drawing of a 1st electrode. It is a figure which shows a pulse voltage. 6 is a schematic diagram of a plasma generator according to Embodiment 2. FIG. FIG. 6 is a schematic diagram of a plasma generator according to a third embodiment. FIG. 6 is a schematic diagram of a plasma generator according to a fourth embodiment. FIG. 9 is a schematic diagram of a plasma generator according to a fifth embodiment. FIG. 10 is a schematic diagram of a plasma generator according to a sixth embodiment. FIG. 10 is a schematic diagram of a plasma generator according to a seventh embodiment. It is a partially broken view of a container. FIG. 10 is a schematic diagram of a plasma generator according to an eighth embodiment. 10 is a schematic diagram of a plasma generator according to Embodiment 9. FIG. FIG. 10 is a schematic diagram of a plasma generator according to a tenth embodiment. FIG. 12 is a schematic diagram of a plasma generator according to an eleventh embodiment. It is a relationship diagram of a sense current and a frequency.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following drawings, components having substantially the same function are denoted by the same reference numerals for the sake of brevity.

(Embodiment 1)
The plasma generator of Embodiment 1 is shown in FIG. This plasma generation apparatus is an apparatus that generates plasma in a container (narrow tube) 10 in which a part of an outer wall is immersed in a liquid 60, that is, in a space adjacent to the liquid 60. The apparatus includes a first electrode 30, a container 10 that stores the first electrode 30 therein, a second electrode 20 that is immersed in the liquid 60, the first electrode 30, the second electrode 20, and the like. And a power source 40 for applying an alternating voltage or a pulse voltage.

  As shown in FIG. 2, the first electrode 30 has a structure in which a coating 32 made of an insulator or a dielectric is applied to the surface of the conductive member 31. The conductive member 31 may be any material as long as it has conductivity such as metal, carbon, and organic conductive material. In this embodiment, a copper wire is used.

  Examples of the insulator constituting the coating 32 include a fluorine resin such as PFA, PTFE, and FEP, an electrically insulating polymer such as polyimide resin, or an electrically insulating inorganic material such as diamond-like carbon (DLC). . Moreover, as a dielectric material which comprises the coating | cover 32, substances with high dielectric constant, such as barium titanate, can be mentioned. In this embodiment, the coating 32 is formed of Teflon (registered trademark) which is a fluororesin.

  Assuming that the coating 32 is not present here, the discharge concentrates on a specific part of the conductive member 31, and the plasma generation part is only around the specific part, so that plasma is generated in the entire pores of the container 10. There is a high possibility that the container 10 will not be broken or the container 10 will be destroyed by the discharge.

  In addition, when an alternating voltage or a pulse voltage is applied between the first electrode 30 and the second electrode 20 to generate plasma around the first electrode 30, the temperature of the first electrode 30 increases. It is preferable that the conductive member 31 and the coating 32 have high heat resistance, specifically, those that do not deteriorate when held at 50 ° C. for 1 hour. From the viewpoint of heat resistance, the conductive member 31 is preferably made of metal, carbon or the like, and the coating 32 is preferably made of fluorine resin, polyimide resin, DLC, barium titanate or the like.

  The container 10 may have any shape. Examples of the shape include a box shape, a bag shape, and a tubular shape in which at least one end is closed. Any material may be used for the container 10. However, a higher electric field can be applied between the first electrode 30 and the second electrode 20 as the insulation of the container 10 is higher, and as a result, plasma is easily generated. The first electrode 30 is preferably sealed in the container 10. If the liquid 60 enters the container 10 and the first electrode 30 and the liquid 60 come into contact with each other, current flows from the second electrode 20 to the first electrode 30 as it is through the liquid 60. This is not preferable because plasma is not generated. In the present embodiment, the container 10 is a PVC thin tube (outer diameter 5 mm, inner diameter 3 mm).

  The second electrode 20 is connected to the power source 40 and grounded by the ground line 70. The shape and material of the second electrode 20 are not particularly limited. For example, the shape of the second electrode 20 may be any shape such as a flat plate shape, a cylindrical shape, a mesh shape, or a wire shape. The material of the second electrode 20 may be any material as long as it is conductive, such as metal, carbon, or an organic conductive material. Furthermore, the surface of the second electrode 20 may be covered with an insulator. In the present embodiment, the metal plate is the second electrode 20.

  The liquid 60 may be any liquid. This is because the ease of current flow and the electric field strength around the first electrode 30 vary depending on the distance between the second electrode 20 and the container 10, the voltage value, the power supply frequency, the material of the container 10, and the like. In consideration of the ease of generating plasma, the liquid 60 preferably has an electric conductivity of 0.055 μS / cm or more or a relative dielectric constant of 60 or more. In the present embodiment, ultrapure water having an electric conductivity of 0.055 μS / cm and a relative dielectric constant of about 80 is used. Note that the shape and material of the tank 50 in which the liquid 60 is placed are not particularly limited. The tank 50 such as a river, a lake, or the sea may be the ground.

  The power source 40 applies an AC voltage or a pulse voltage, and the first electrode 30 and the second electrode 20 such as the shape, material, and length of the first electrode 30 and the material and thickness of the container 10 Since the plasma intensity is greatly influenced by whether the plasma is generated depending on the distance, the type of the liquid 60, the type of the solute, the temperature, and the like, the first voltage is not the applied voltage but is important for the generation of the plasma. Since it is the electric field intensity around the electrode 30, the frequency and magnitude of the AC voltage or pulse voltage are not particularly limited. As shown in FIG. 3, the pulse voltage is preferably a pulse of changing polarity (+ to-or-to +) or a pulse rising from 0 V. When the pulse voltage is continuously supplied, the plasma continues. This is preferable. The pulse voltage continuously supplied in this way can be said to be a square wave AC voltage.

Although the frequency and voltage of the power supply 40 are not particularly limited, the frequency is preferably 0.1 Hz to 100 MHz for practical use as a power supply device, and 50 Hz to 1 MHz is preferable in consideration of the ease of plasma generation. The voltage is preferably 1 V to 500 kV because plasma is easily generated, and 1 V to 100 kV is preferable from the viewpoint of easy handling of the apparatus. Alternatively, the electric field strength in the vicinity of the first electrode 30 when an AC voltage or a pulse voltage is applied to the first electrode 30 by the power supply 40 is preferably 10 ⁴ V / m or more and 10 ¹⁰ V / m or less.

  Next, a method for generating plasma using the plasma generator of this embodiment will be described.

  A tank 50 filled with the liquid 60 is prepared. Then, the container 10 in which the first electrode 30 is stored is placed in the liquid 60 and the outer surface of the container 10 is brought into contact with the liquid 60. Note that the first electrode 30 is connected to the power source 40.

  Then, the second electrode 20 is placed in the liquid 60 and connected to the power source 40. When an AC voltage or a pulse voltage is applied between the first electrode 30 and the second electrode 20, a current flows through the liquid 60 and plasma is generated in the container 10. In this case, since the wall thickness of the container 10 is constant, the electric field intensity around the first electrode 30 varies depending on the distance between the first electrode 30 and the inner wall of the container 10. In the longitudinal direction of one electrode 30, the distance from the inner wall of the container 10 is substantially constant at any position of the first electrode 30, and plasma having substantially constant intensity is generated in the longitudinal direction of the first electrode 30. .

  As described so far, in this embodiment, the first electrode 30 including the conductive member 31 covered with an insulator or a dielectric is stored in the container 10, and the outer wall of the container 10 is stored in the liquid 60. In addition, the second electrode 20 is electrically connected to the liquid 60 and an alternating voltage or a pulse voltage is applied between the first electrode 30 and the second electrode 20 to generate plasma. Plasma can be generated in the space adjacent to the liquid, that is, the interior of the container 10, which was not possible with the conventional apparatus. In addition, the plasma generator of this embodiment has a very simple structure, and can reduce the manufacturing cost. Further, plasma generation can be easily performed by a trained person. In the present embodiment, since the container 10 is a narrow tube with the end closed and the first electrode 30 is linear, plasma having a substantially constant intensity is continuously generated along the length direction of the first electrode 30. appear. Note that the degree of plasma generation can be determined by the intensity of light emission or the discharge current per unit length in the length direction of the first electrode 30. Further, since the electric field concentrates at the tip of the linear electrode, if the thickness of the coating 32 at the tip of the first electrode 30 is increased or the coating of a material having higher insulating and dielectric properties than the tip only is applied, It becomes easy to obtain a substantially uniform plasma in the length direction of the electrode 30. Even if the liquid 60 is other than ultrapure water and has lower electrical conductivity, it is possible to generate plasma by adjusting the conditions of the power source and the distance between the first electrode 30 and the second electrode 20. It is.

(Embodiment 2)
As shown in FIG. 4, the plasma generator according to the second embodiment is different from the second electrode 20 of the plasma generator according to the first embodiment. Since the plasma generating apparatus and the plasma generating method according to the present embodiment are mostly the same as those of the first embodiment, differences will be mainly described.

  In the present embodiment, the second electrode 22 is formed by applying an insulating coating to a metal wire. The structure of the second electrode 22 is the same as that of the first electrode 30. Here, the second electrode 22 uses the same Teflon (registered trademark) -coated copper wire as the first electrode 30, and all the portions immersed in the liquid 60 are covered. Further, unlike the first embodiment, the second electrode 22 is not grounded.

  Even when the second electrode 22 is covered with an insulator, when an AC voltage or a pulse voltage is applied between the first electrode 30 and the second electrode 22 from the power supply 40, the first electrode 30 is caused by dielectric polarization. An electric field is generated around the substrate to generate plasma. Therefore, the same effects as those of the first embodiment are obtained.

(Embodiment 3)
As shown in FIG. 5, the plasma generator according to the third embodiment has a different form of the second electrode 20 of the plasma generator according to the first embodiment. Since the plasma generating apparatus and the plasma generating method according to the present embodiment are mostly the same as those of the first embodiment, differences will be mainly described.

  In this embodiment, the 2nd electrode 24 is made to contact the outer wall surface of the tank 50 as a metal plate. If the tank 50 has conductivity, plasma is generated as in the first embodiment, and if the tank 50 is an insulator or a dielectric, plasma is generated as in the second embodiment. Therefore, this embodiment has the same effect as the first embodiment.

(Embodiment 4)
As shown in FIG. 6, the plasma generator according to the fourth embodiment is the same as the first embodiment in the liquid 60, the tank 50, the first electrode 30, and the power source 40, but the other parts are different from those in the first embodiment. Therefore, the different part will be explained.

  In this embodiment, the container 12 has translucency. Accordingly, when plasma is generated in the container 12 and thereby visible light or ultraviolet light is generated, the light passes through the container 12 and is irradiated onto the liquid 60. Thereby, the sterilization of the liquid 60, the chemical reaction in the liquid 60, etc. can be promoted. In addition, as the translucency of the container 12, it is preferable to transmit 10% or more of light having a desired wavelength in light generated by plasma, and it is more preferable to transmit 50% or more.

  Furthermore, in this embodiment, an adapter 85 is attached to the opening of the container 12 that is not immersed in the liquid 60, and a gas introduction unit 80 is connected to the adapter 85. A predetermined gas, for example, a gas that easily generates plasma, such as Ar or He, is introduced into the container 12 from the gas introduction unit 80, thereby generating more light or generating light of a desired wavelength. Let An upper portion of the adapter 85 is provided with a discharge port for discharging the gas in the container 12 pushed by a predetermined gas.

  In the present embodiment, the power supply 40 is grounded via the connection line 71. The liquid 60 is grounded by a ground wire 72.

  In the present embodiment, the same effects as in the first embodiment can be obtained, and light can be easily applied to the liquid 60 around the container 12 and the inner wall of the tank 50.

(Embodiment 5)
As shown in FIG. 7, the plasma generating apparatus according to the fifth embodiment is different from the fourth embodiment in the container 14, but the other parts are the same as those in the fourth embodiment.

  The container 14 of this embodiment uses the tip portion 15 as a membrane filter. This membrane filter does not allow molecules of the liquid 60 to pass, but allows active species such as radicals and ions generated in the container 14 by the plasma to pass. Accordingly, active species generated by the plasma are dissolved in the liquid 60.

  In the present embodiment, a predetermined gas is sent from the gas introduction unit 80 into the container 14, and this gas is changed into active species by plasma. As the predetermined gas, oxygen, nitrogen, organic molecules, or the like can be appropriately selected depending on the purpose of the reaction to be performed by being dissolved in the liquid 60.

  In the present embodiment, the same effects as in the first embodiment can be obtained, and a desired active species can be easily dissolved in the liquid 60 by appropriately selecting a gas species, and does not occur under normal conditions such as room temperature and normal pressure. The reaction can be carried out at normal temperature and pressure.

(Embodiment 6)
As shown in FIG. 8, the plasma generator according to the sixth embodiment is the same as the first embodiment in the liquid 60, the tank 50, the first electrode 30, and the power source 40, but the other parts are different from the first embodiment. Therefore, the different part will be explained.

  The power supply 40 according to the present embodiment is electrically connected to the first electrode 30 and is also connected to the second electrode 22 that is a covered ground wire. The second electrode 22 is formed by coating an outer surface of a metal wire with an insulator such as a resin. The second electrode 22 is inserted into the ground 1. The liquid 60 is grounded by a ground wire 72. Even when the power source 40 is inserted into the ground 1 by the second electrode 22, the liquid 60 is energized by dielectric polarization, and plasma is generated around the first electrode 30.

  In the present embodiment, the container 12 has translucency as in the fourth embodiment, and a predetermined gas advantageous for light generation is enclosed in the container 12. Accordingly, when plasma is generated in the container 12 and thereby visible light or ultraviolet light is generated, the light passes through the container 12 and is irradiated onto the liquid 60.

  In the present embodiment, the same effects as in the fourth embodiment are obtained.

(Embodiment 7)
Embodiment 7 relates to a plasma generation apparatus and a plasma generation method for generating a plasma in a living body by inserting a container into the living body.

  In the present embodiment, as shown in FIG. 9, a container 110 and a second electrode 120 that is a metal wire are inserted into a living body 100. A first electrode 30 is stored in the container 110 as shown by a partially broken view in FIG. The first electrode 30 is the same as that of the first embodiment. The first electrode 30 and the second electrode 120 are connected to a power source 40, and an AC voltage or a pulse voltage is applied between them by the power source 40. The second electrode 120 is grounded by the ground line 70.

  The AC voltage or the pulse voltage has been described in the first embodiment, but in this embodiment, since a voltage is applied to the living body 100, this point will be further described. FIG. 15 is a diagram illustrating the influence of frequency on the sensing current described in Non-Patent Document 1. This figure is a graph showing how much current is felt when an AC current of a certain frequency is applied to the human body with the frequency [Hz] on the horizontal axis and the sense current [mA] on the vertical axis. is there. (A) is a value sensed by 99.5% of the subjects, (b) is a value sensed by 50% of the subjects, and (c) is a value sensed by 0.5% of the subjects. As can be seen from this figure, if plasma is generated in the region below the curve of (c), plasma generation can be performed in the living body without sensing that current is flowing.

  The container 110 is preferably made of a material that is easily compatible with a living body, such as fluororesin or silicone, but may be any material as long as it is inserted for a short time. The container 110 may be inserted from a hole on the surface of the living body such as the mouth, nostril, anus, or the living body 100 may be cut. Moreover, you may insert in a blood vessel like a catheter. The living body 100 may be any living body such as mammals such as horses, cows, dogs, and humans, reptiles, and fish.

  This embodiment has an effect that plasma can be easily generated in a living body.

(Embodiment 8)
As shown in FIG. 11, the eighth embodiment is different from the seventh embodiment in that the second electrode 122 is different and the other configuration is the same. Therefore, the difference from the seventh embodiment will be described. In FIG. 11, only a part of the surface of the living body 100 is shown, and other parts are omitted. In FIG. 11, the upper side of the surface of the living body indicated by reference numeral 100 is the living body 100. This point is the same for FIGS.

  The second electrode 122 of this embodiment is a coated metal wire. A metal wire is coated with an insulating resin. Even if there is an insulating coating, plasma is generated in the container 110 in the same state as when the living body 100 is energized by dielectric polarization.

  This embodiment has the same effect as the seventh embodiment.

(Embodiment 9)
The plasma generator according to the ninth embodiment has the same power source 40 as that of the seventh embodiment, but the other parts are different from those of the seventh embodiment.

  In this embodiment, the container 112 has translucency. Accordingly, when plasma is generated in the container 112 and thereby visible light or ultraviolet light is generated, the light passes through the container 112 and is irradiated into the living body 100. Thereby, sterilization in living body 100, treatment of an affected part, etc. can be performed. In addition, as the translucency of the container 12, it is preferable to transmit 10% or more of light having a desired wavelength in light generated by plasma, and it is more preferable to transmit 50% or more.

  Further, in the present embodiment, an adapter 85 is attached to an opening portion of the container 112 that is exposed to the outside of the living body 100, and a gas introduction unit 80 is connected to the adapter 85. A predetermined gas, for example, a gas that easily generates plasma, such as Ar or He, is introduced into the container 112 from the gas introduction unit 80, thereby generating more light or light having a desired wavelength. Let An upper portion of the adapter 85 is provided with a discharge port for discharging the gas in the container 112 pushed out by a predetermined gas.

  The power supply 40 is grounded by a ground wire 72, and the second electrode 24 that is a metal plate is in contact with the surface of the living body 100, and the second electrode 24 is grounded by the ground wire 24. When the second electrode 24 is brought into contact with the surface of the living body 100, it is preferable to apply a cream or jelly containing moisture to the surface of the living body 100 to ensure electrical conduction between the two. Note that in order to ground the living body 100, a part of the living body 100 itself may be touched to the ground without the second electrode 24 being grounded.

  This embodiment has the same effect as that of the seventh embodiment, and also has the effect that light (particularly ultraviolet light) can be easily irradiated into the living body 100.

(Embodiment 10)
In the plasma generator according to the tenth embodiment, the container 114 is different from the ninth embodiment as shown in FIG. 13, but the other parts are the same as those of the ninth embodiment.

  The container 114 of this embodiment uses the tip portion 115 as a membrane filter. This membrane filter does not allow liquid molecules in the living body 100 to pass, but allows active species such as radicals and ions generated in the container 114 by plasma to pass. Therefore, active species generated by plasma dissolve in the living body 100.

  In the present embodiment, a predetermined gas is sent from the gas introduction unit 80 into the container 114, and this gas is changed into active species by plasma. As the predetermined gas, oxygen, nitrogen, organic molecules, or the like can be appropriately selected depending on the purpose of reaction, treatment, etc. to be dissolved in the living body 100.

  In the present embodiment, the same effects as in the seventh embodiment can be obtained, and a desired active species can be easily dissolved in the living body 100 by appropriately selecting a gas species, and chemical reaction and treatment in the living body 100 can be performed. It can be carried out.

(Embodiment 11)
As shown in FIG. 14, the plasma generator according to the eleventh embodiment is the same as the seventh embodiment in the living body 100, the first electrode 30, and the power supply 40, but the other parts are different from the seventh embodiment. Explain the different parts.

  The power supply 40 of the present embodiment is electrically connected to the first electrode 30 and is grounded by a ground line 72. The second electrode 24 is a metal plate that is in contact with the surface of the living body 100 as in the tenth embodiment, but is connected to the covered ground wire 26 via the ground wire 71. The covered ground wire 26 is a metal wire whose outer surface is covered with an insulator such as resin. The covered ground wire 26 is inserted into the ground 1. Even if the second electrode 24 is inserted into the ground 1 by the covered ground line 26, plasma is generated around the first electrode 30 due to dielectric polarization.

  In the present embodiment, the container 112 has translucency as in the ninth embodiment, and a predetermined gas advantageous for light generation is sealed in the container 112. Accordingly, when plasma is generated in the container 112 and thereby visible light or ultraviolet light is generated, the light passes through the container 112 and is irradiated into the living body 100.

  In the present embodiment, the same effects as in the ninth embodiment are obtained.

(Other embodiments)
The above embodiments are examples of the present invention, and the present invention is not limited to these examples. For example, the shape of the conductive member of the first electrode is not limited to a linear shape, and may be any shape such as a plate shape or a foil shape.

  The discharge generated in the first electrode is not particularly limited, such as dielectric barrier discharge, glow discharge, corona discharge. Any discharge form may be used as long as plasma is generated.

  In the devices of the first to third, seventh, seventh, and eighth embodiments, a gas introduction unit may be attached as in the fourth, fifth, ninth, and tenth, and a predetermined gas may be introduced to generate plasma.

  In the first to third and fifth embodiments, at least a part of the container may be made of a translucent material and light may be irradiated to the liquid by plasma. In the first to fourth and sixth embodiments, at least a part of the container may be a permeable membrane, and active species generated by the plasma may be released into the liquid.

  In Embodiments 7, 8, and 10, at least a part of the container may be made of a light-transmitting material and light may be irradiated into the living body by plasma. In the seventh to ninth and eleventh embodiments, at least a part of the container may be a permeable membrane, and active species generated by plasma may be released into the living body.

  The first electrode may be entirely contained in the container, but a part of the first electrode may protrude outside the container. In that case, the portion of the first electrode that protrudes outside the container is prevented from touching the liquid or the living body. However, if the covering of the protruding part is sufficiently thick so that no current flows even when it comes into contact with a liquid or a living body, this part can no longer be said to be the first electrode. May be in contact with a liquid or a living body.

  As described above, the plasma generation apparatus and the plasma generation method according to the present invention can generate plasma in a liquid adjacent space or in a living body, and are useful as liquid sterilization, chemical reaction promotion, a treatment apparatus, and the like.

10, 12, 14 Container 15 Membrane filter (permeable membrane)
20, 22, 24 Second electrode 30 First electrode 31 Conductive member 32 Coating 40 Power supply 60 Liquid 80 Gas introduction part (gas inflow member)
100 Living body 110 Container 112 Container 114 Container 115 Membrane filter (permeable membrane)
120 Second electrode 122 Second electrode 124 Second electrode

Claims (8)

A plasma generator for generating plasma in a living body,
A first electrode comprising a conductive member coated with an insulator or a dielectric, and generating plasma;
Storing the first electrode, inserted into the living body, interposed between the first electrode and the living body, and made of an insulator; a second electrode electrically connected to the living body;
A plasma generator, comprising: a power source that applies an AC voltage or a pulse voltage between the first electrode and the second electrode.   The plasma generating apparatus according to claim 1, wherein the conductive member is a linear member, and the container is a thin tube.   The plasma generator according to claim 1, wherein the container has translucency.   The plasma generator according to any one of claims 1 to 3, further comprising a gas inflow member for allowing a predetermined gas to flow into the container.   The plasma generator according to any one of claims 1 to 3, wherein a predetermined gas is sealed in the container.   6. The plasma generating apparatus according to claim 4, wherein at least a part of the container is made of a permeable film through which the predetermined gas selectively passes a substance chemically changed by the plasma. A plasma generator for generating plasma in a space adjacent to a liquid,
A first electrode comprising a conductive member coated with an insulator or a dielectric, and generating plasma;
A container containing the first electrode and having an outer surface in contact with the liquid and made of an insulator;
A second electrode electrically connected to the liquid;
A power source for applying an AC voltage or a pulse voltage between the first electrode and the second electrode,
A plasma generator, wherein a predetermined gas is sealed in the container.   The plasma generating apparatus according to claim 7, wherein at least a part of the container is made of a permeable film that allows the predetermined gas to selectively pass a substance chemically changed by the plasma.

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