JP2004359307A - Sterilization method and apparatus for container, and processing tank for sterilization used for the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To sterilize the inner and outer surfaces of a container simultaneously using atmospheric plasma. <P>SOLUTION: A processing tank 3 has a housing space S, at least the inside of which is enclosed with a dielectric, and the container 2 to be sterilized is arranged in the housing space S so that the outer peripheral surface 2a and the bottom surface 2b of the container 2 are enclosed with the dielectric. A discharge electrode 4 is inserted in the container 2, and the outer peripheral surface 2a of the container 2 is surrounded by an outer peripheral counter electrode 5 via the dielectric while the bottom surface 2b of the container 2 is set counter to a bottom counter electrode 6 via the dielectric. A prescribed gas is introduced into the housing space S. In this arrangement, high-voltage pulses are applied across the discharge electrode 4 and the outer peripheral counter electrode 5, and the bottom counter electrode 6 under normal temperature and pressure to generate atmospheric plasma inside/outside of the container 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００８６】
【発明の効果】
以上説明したように、本発明によれば、放電極と対向電極との間に高電圧パルスを印加することにより容器の内外に大気圧プラズマを発生させ、プラズマ化されたガスと容器の内面と外面とを接触させてそれらの面を同時に効率よく殺菌することができる。
【図面の簡単な説明】
【図１】本発明の一実施形態に係る殺菌装置の要部を示す部分破断断面図。
【図２】放電極に付された凹凸を示す図。
【図３】外周対向電極と底面対向電極との関係を示す図。
【図４】殺菌装置の付帯設備として設けられる水着装置を示す図。
【図５】図１の殺菌装置を使用した殺菌手順を示す図。
【図６】処理槽の他の実施形態を示す図。
【図７】支持手段の他の実施形態を示す図。
【図８】図７のステージを同図の矢印ＶＩＩＩ方向からみた状態を示す図。
【図９】支持手段のさらに他の実施形態を示す図。
【図１０】容器の首部を把持する支持手段の実施形態を示す図。
【図１１】外周対向電極及び底面対向電極の外側に保護層を設けた実施形態を示す図。
【図１２】放電極の他の実施形態を示す図。
【図１３】放電極のさらに他の実施形態を示す図。
【図１４】放電極をリング状に形成した実施形態を示す図。
【図１５】水着装置の他の実施形態を示す図。
【図１６】容器内にガスを導入するノズルの他の実施形態を示す図。
【符号の説明】
１ 殺菌装置
２ 容器
２ａ 外周面
２ｂ 底面
２ｄ 首部
２ｅ 内周面
３ 処理槽
４ 放電極
４ａ ねじ山
４ｂ 軸
４ｃ 円板
５ 外周対向電極
６ 底面対向電極
６ａ 底面対向電極の外周
７ ガス導入装置（ガス導入手段）
８ パルス電源（高電圧パルス印加手段）
１０ ステージ
１０ｃ リブ（支持手段）
１１ 筒状体
１１ａ、１１ｂ 開口部
１１ｄ 上部筒状体
１１ｅ 下部筒状体
１２ 蓋板
１５ 第１のガスノズル
１６ 第２のガスノズル
１７ ガス供給源
１８ スペーサ（支持手段）
１９ 隙間
２０ 網（支持手段）
２１ 脚部（支持手段）
２２ 爪部材（支持手段）
２３ 脚部（支持手段）
２５、２６ 保護層
３０ 水着装置
３２、３３ スプレーノズル
３５ タンク[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for sterilizing packaging containers and the like by atmospheric pressure plasma.
[0002]
[Prior art]
As a method for sterilizing the inner surface of a packaging container such as a PET bottle, a rare gas such as argon gas is introduced into the container to be sterilized, a discharge electrode is inserted, and the outer periphery of the container is surrounded by a counter electrode with a dielectric interposed therebetween. A method is known in which a high-voltage pulse is applied between a discharge electrode and a counter electrode to generate atmospheric pressure plasma in a container, and the gas in the plasma state is brought into contact with the container to sterilize the inner surface of the container. (See, for example, Patent Document 1).
[0003]
[Patent Document 1]
JP 2003-62047 A
[0004]
[Problems to be solved by the invention]
Although the above-described plasma sterilization method is exclusively for the inner surface of the container, in order to prevent contamination of the aseptic filling machine that fills the container with the contents in an aseptic environment, not only the inner surface but also the outer surface of the container carried into the filling machine is used. It needs to be sterilized. Conventionally, the outer surface of a container is sterilized by a method such as spraying a mist of a disinfectant such as hydrogen peroxide onto the outer surface of the container, but sterilizing the outer surface and the inner surface of the container by different methods is a labor-intensive process. And the burden of capital investment also increases, which is not desirable.
[0005]
Accordingly, an object of the present invention is to provide a method and an apparatus capable of simultaneously sterilizing the inner and outer surfaces of a container using atmospheric pressure plasma, and a sterilizing treatment tank suitable for them.
[0006]
[Means for Solving the Problems]
Hereinafter, the present invention will be described. In addition, in order to facilitate understanding of the present invention, reference numerals in the accompanying drawings are added in parentheses, but the present invention is not limited to the illustrated embodiment.
[0007]
In the first sterilization method of the present invention, a container (2) to be sterilized having an opening is disposed in a storage space (S) in a processing tank (3) whose inner surface is at least surrounded by a dielectric. An outer peripheral surface (2a) and a bottom surface (2b) of the container are covered with the dielectric, a discharge electrode (4) is inserted from the opening of the container, and an outer peripheral surface of the container is sandwiched by the dielectric. Surrounded by a counter electrode (5), with the bottom surface of the container facing the bottom counter electrode (6) with the dielectric interposed therebetween, between the discharge electrode and the outer peripheral counter electrode and the bottom counter electrode. A high voltage pulse is applied under normal temperature and normal pressure to generate atmospheric pressure plasma inside and outside the container, thereby simultaneously sterilizing the inner surface and the outer surface of the container.
[0008]
According to this sterilization method, since each of the outer peripheral surface and the bottom surface of the container faces the outer peripheral counter electrode or the bottom counter electrode with the dielectric interposed therebetween, a high voltage pulse is applied between the discharge electrode and each counter electrode. As a result, gas existing inside and outside the container is turned into plasma, so that not only the inner surface but also the outer peripheral surface and the bottom surface of the container can be brought into contact with the gas that has been turned into plasma (hereinafter sometimes referred to as plasma gas). Thereby, the inner surface and the outer surface of the container can be efficiently and simultaneously sterilized.
[0009]
In the first sterilization method of the present invention, a predetermined gas may be introduced into and out of the container arranged in the storage space. According to this aspect, since the plasma intensity inside and outside the container increases, the sterilizing effect can be enhanced.
[0010]
Further, prior to the application of the high voltage pulse, moisture may be attached to the inner surface and the outer surface of the container. The sterilization effect can be further enhanced by generating plasma in a state where moisture is attached. In the first sterilization method, the adhesion of moisture may be performed in conjunction with the introduction of gas into and out of the container.
[0011]
In the second sterilization method of the present invention, a container (2) to be sterilized having an opening is disposed in a storage space (S) in a processing tank (3) whose inner surface is at least surrounded by a dielectric. An outer peripheral surface (2a) and a bottom surface (2b) of the container are covered with the dielectric, a discharge electrode (4) is inserted from the opening of the container, and an outer peripheral surface of the container is sandwiched by the dielectric. A high-voltage pulse is applied between the discharge electrode and the outer peripheral counter electrode under normal temperature and normal pressure with a predetermined gas being introduced into and out of the container placed in the receiving space and surrounded by the counter electrode (5). Is applied to generate atmospheric pressure plasma inside and outside the container, thereby simultaneously sterilizing the inner and outer surfaces of the container.
[0012]
According to this sterilization method, the gas introduced into and out of the container is turned into plasma by application of a high-voltage pulse, and the inner surface and the outer surface of the container are uniformly contacted with the plasma gas so that they can be simultaneously and efficiently sterilized. In the second sterilization method, it is optional whether or not the bottom surface side of the container faces the bottom surface counter electrode. Depending on the shape of the bottom surface of the container, the plasma gas may be supplied to the bottom surface side of the container even without the bottom facing electrode, and a sterilizing effect may be generated. In particular, there is such a tendency in a container (for example, a bottle) whose outer peripheral surface is sufficiently large as compared with the bottom surface. Also in the second sterilization method of the present invention, moisture may be attached to the inner surface and the outer surface of the container before the application of the high voltage pulse.
[0013]
In the third sterilization method of the present invention, a container (2) to be sterilized having an opening is disposed in a storage space (S) in a processing tank (3) whose inner surface is at least surrounded by a dielectric. An outer peripheral surface (2a) and a bottom surface (2b) of the container are covered with the dielectric, a discharge electrode (4) is inserted from the opening of the container, and an outer peripheral surface of the container is sandwiched by the dielectric. A high voltage pulse is applied between the discharge electrode and the outer peripheral counter electrode under normal temperature and normal pressure while surrounding the inner and outer surfaces of the container with moisture by surrounding with the counter electrode (5). The inner and outer surfaces of the vessel are simultaneously sterilized by generating atmospheric pressure plasma.
[0014]
According to this sterilization method, the plasma is generated in a state where moisture is adhered to the inside and outside of the container, so that the sterilization effect is enhanced inside and outside the container, and these can be simultaneously and efficiently sterilized. In the third sterilization method as well, it is optional whether or not the bottom surface side of the container faces the bottom surface counter electrode. This is because, similarly to the second sterilization method, a sterilization effect can be produced even without the bottom facing electrode.
[0015]
In the above sterilization method, particularly when gas is introduced into and out of the container, the opening (11b) for taking the container in and out of the treatment tank is closed with the lid (12) during the application of the high-voltage pulse. You may make it narrow. By providing such a lid, diffusion of the gas introduced into the processing tank to the outside of the processing tank can be suppressed, and plasma can be generated more efficiently.
[0016]
Further, the gas may be introduced before the application of the high-voltage pulse, and the flow rate of the gas introduced may be reduced during the application of the high-voltage pulse as compared to before the application. Before the application of the high-voltage pulse, a gas is introduced at a relatively large flow rate so that the gas present in the processing tank can be quickly replaced with a newly introduced desired gas. On the other hand, a uniform plasma can be stably generated by reducing the gas introduction flow rate during the application of the high voltage pulse.
[0017]
Further, when introducing the gas, at least the surface is made of a dielectric so that a gap (19) through which the gas flows is formed between the container and the inner bottom surface of the processing tank in the accommodation space. The container may be supported by the configured support means (18; 10c; 20, 21; 22, 23). By providing such a gap, it is possible to sufficiently introduce a gas also to the inner bottom surface side of the processing tank and enhance the sterilizing effect. In addition, as long as a gap can be generated between the container and the inner bottom surface of the processing tank, the supporting form of the supporting means is not limited. Therefore, the supporting means may be arranged between the container and the inner bottom surface of the processing tank to support the container from below, or the supporting means may be arranged above the container and the container may be suspended and supported by a part thereof. May be.
[0018]
In the case of attaching moisture to the container in the sterilization method of the present invention, it is desirable to attach the moisture so that fogging occurs on the inner and outer surfaces of the container. By adhering water to such an extent, the sterilizing effect can be sufficiently improved.
[0019]
When the bottom facing electrode is provided in the sterilization method of the present invention, the outer periphery (6a) of the bottom facing electrode may be aligned with the outer periphery facing electrode, or may be located outside the outer periphery facing electrode. According to this aspect, it is possible to prevent the concentration of discharge between the outer periphery of the bottom facing electrode and the discharge electrode, and to uniformly generate a discharge between each of the outer periphery counter electrode and the bottom facing electrode and the discharge electrode. it can.
[0020]
In the sterilization method of the present invention, the surface of the insertion range of the discharge electrode into the container may be provided with irregularities over substantially the entire insertion range. By providing irregularities on the surface of the discharge electrode, the concentration of discharge at the tip of the discharge electrode can be suppressed, and uniform discharge can be generated in almost the entire insertion range of the container. The irregularities can be provided by forming the surface of the insertion area in a spiral shape.
[0021]
In the first sterilization apparatus (1) of the present invention, a storage space (S) for a container (2) to be sterilized is provided therein, and an outer peripheral surface (2a) and a bottom surface (2a) of the container disposed in the storage space are provided. The inner surface covering 2b) is composed of a dielectric (10, 11), and an outer peripheral counter electrode (5) is provided so as to surround the outer peripheral surface of the container with the dielectric interposed therebetween. A treatment tank (3) provided with a bottom facing electrode (6) so as to face the bottom surface of the container, a discharge electrode (4) insertable into the container disposed in the accommodation space, High voltage pulse applying means (8) for applying a high voltage pulse between the discharge electrode and the outer peripheral counter electrode and the bottom counter electrode is provided.
[0022]
According to this sterilizer, by inserting the discharge electrode into the container and applying a high voltage pulse between the discharge electrode and each counter electrode, the gas existing inside and outside the container is turned into plasma, thereby By implementing the sterilization method of the present invention, the inner and outer surfaces of the container can be sterilized by plasma.
[0023]
The first sterilization apparatus of the present invention may include a gas introduction unit (7) for introducing a predetermined gas into and out of the container disposed in the storage space. In this case, since the plasma intensity inside and outside the container is increased, the sterilizing effect can be enhanced.
[0024]
Further, a swimsuit device (30) for attaching moisture to the inner surface and the outer surface of the container may be provided. By attaching moisture to the inner and outer surfaces of the container prior to the application of the high voltage pulse, the sterilizing effect can be further enhanced. The swimwear device may be provided in combination with the gas introduction means.
[0025]
In the second sterilization apparatus (1) of the present invention, an accommodation space (S) for a container (2) to be sterilized is provided therein, and an outer peripheral surface (2a) and a bottom surface (2) of the container arranged in the accommodation space are provided. A treatment tank (3) in which an inner surface side covering 2b) is composed of a dielectric (10, 11), and an outer peripheral counter electrode (5) is provided so as to surround the outer peripheral surface of the container with the dielectric interposed therebetween; A discharge electrode (4) that can be inserted into the container disposed in the storage space, and gas introduction means (7) for introducing a predetermined gas into and out of the container disposed in the storage space; High voltage pulse applying means (8) for applying a high voltage pulse between the discharge electrode and the outer peripheral counter electrode is provided.
[0026]
According to this sterilizing apparatus, by introducing gas into and out of the container and applying a high-voltage pulse, the plasma intensity inside and outside the container is increased, so that they can be simultaneously and efficiently sterilized. In addition, similarly to the second sterilization method, in the second sterilization apparatus, whether or not the bottom surface side of the container faces the bottom surface counter electrode is optional. The second sterilization apparatus of the present invention may also include a swimwear device (30) for attaching moisture to the inner surface and the outer surface of the container.
[0027]
In the third sterilization apparatus of the present invention, a storage space (S) for the container (2) to be sterilized is provided therein, and the outer peripheral surface (2a) and the bottom surface (2b) of the container disposed in the storage space are provided. A processing tank (3) in which an inner surface to be covered is made of a dielectric (10, 11) and an outer peripheral counter electrode (5) is provided so as to surround an outer peripheral surface of the container with the dielectric interposed therebetween; A discharge electrode (4) that can be inserted into the inside of the container, a swimsuit device (30) that attaches moisture to the inner surface and the outer surface of the container, and a height between the discharge electrode and the outer peripheral counter electrode. High voltage pulse applying means (8) for applying a voltage pulse.
[0028]
According to this sterilizing device, by applying moisture to the inside and outside of the container by the swimsuit device and applying a high voltage pulse between the electrodes, a high sterilizing effect is generated inside and outside the container, and these are simultaneously and efficiently sterilized. Can be. In addition, similarly to the third sterilization method, in the third sterilization apparatus, whether or not the bottom surface side of the container faces the bottom surface counter electrode is optional.
[0029]
When the gas introducing means is provided in the sterilization apparatus of the present invention, the treatment tank is further provided with an opening (11b) for taking the container in and out, and an openable / closable lid (12) for narrowing the opening. You may. According to this aspect, it is possible to prevent the gas introduced into the processing tank from diffusing out of the processing tank.
[0030]
Further, in the housing space, the container is supported so that a gap (19) through which the gas flows between the container and the inner bottom surface of the processing tank is formed. At least the surface is formed of a dielectric. Support means (18; 10c; 20, 21; 22, 23) may be provided. In this case, the sterilizing effect can be enhanced by sufficiently introducing gas into the inner bottom surface of the processing tank. In addition, similarly to the case of the above-mentioned sterilization method, in the sterilization apparatus of the present invention, the supporting form of the support means is not limited as long as a gap can be generated between the container and the inner bottom surface of the processing tank.
[0031]
In the sterilization apparatus of the present invention, when the bottom facing electrode is provided, the outer periphery of the bottom facing electrode may coincide with the outer periphery facing electrode, or may be located outside the outer periphery facing electrode. In this case, as described above, the concentration of discharge between the outer periphery of the bottom facing electrode and the discharge electrode can be suppressed, and the discharge can be uniformly generated between the discharge electrode and each counter electrode.
[0032]
In the sterilization apparatus of the present invention, at least a part of the processing tank may be provided with a light transmitting property so that a discharge phenomenon occurring in the processing tank can be observed from the outside. According to this aspect, the state of generation of plasma in the processing tank can be grasped by analyzing the emission spectrum associated with the discharge phenomenon outside the processing tank, and the sterilization process can be managed.
[0033]
In the sterilization apparatus of the present invention, the outer peripheral counter electrode may be metal-deposited on a dielectric constituting the treatment tank. If metal vapor deposition is used, the outer peripheral counter electrode can be formed thinly and uniformly. Further, by forming the outer peripheral counter electrode to be thin, the outer peripheral counter electrode can be provided with a light-transmitting property. In this case, it is possible to observe the discharge phenomenon inside the processing tank through the outer peripheral counter electrode.
[0034]
In the sterilization apparatus of the present invention, the outer peripheral counter electrode may be formed by applying a conductive paint to a dielectric constituting the treatment tank.
[0035]
Further, a protective layer (25) may be provided outside the outer peripheral counter electrode. Thus, the effect of preventing the outer peripheral counter electrode from being damaged and deteriorated can be enhanced.
[0036]
In the sterilization apparatus of the present invention, in particular, when the bottom facing electrode is provided, the above-described aspect relating to the outer periphery facing electrode can be applied to the bottom facing electrode. That is, the bottom facing electrode may be metal-deposited on the dielectric constituting the processing bath, and the deposited bottom facing electrode may have a light-transmitting property. The bottom facing electrode may be formed by applying a conductive paint to the dielectric constituting the treatment tank. A protective layer (26) may be provided outside the bottom facing electrode.
[0037]
In the sterilizing apparatus of the present invention, the surface of the insertion range of the discharge electrode into the container may be provided with irregularities over substantially the entire insertion range. As a result, as described above, a discharge can be uniformly generated over substantially the entire insertion range of the discharge electrode. In addition, the unevenness can be provided by forming the surface of the insertion range in a spiral shape.
[0038]
Further, a range in which the discharge electrode is inserted into the container may be formed in a shape along an inner peripheral surface of the container. This makes it possible to adjust the discharge electrode to the change in the cross-sectional shape and cross-sectional dimension of the container, thereby suppressing a change in the distance between the counter electrode and the discharge electrode. It can be equally contacted with the plasma gas.
[0039]
In the first processing tank of the present invention, an accommodation space (S) for a container (2) to be sterilized is provided therein, and an outer peripheral surface (2a) and a bottom surface (2b) of the container disposed in the accommodation space are provided. The inner surface to be covered is made of a dielectric material (10, 11), and the opposing electrodes (5 and / or 6) are opposed to at least one of the outer peripheral surface and the bottom surface of the container with the dielectric material interposed therebetween. A treatment tank (3) for atmospheric pressure plasma sterilization provided, wherein the counter electrode is formed by metal deposition.
[0040]
In the second processing tank of the present invention, an accommodation space (S) for the container (2) to be sterilized is provided therein, and an outer peripheral surface (2a) and a bottom surface (2b) of the container arranged in the accommodation space are provided. ) Is formed of a dielectric (10, 11), and the opposing electrodes (5 and / or 6) are opposed to at least one of the outer peripheral surface and the bottom surface of the container with the dielectric interposed therebetween. A treatment tank (3) for atmospheric pressure plasma sterilization provided, wherein the counter electrode is formed by applying a conductive paint to the dielectric.
[0041]
Further, in the third processing tank of the present invention, an accommodation space (S) for the container (2) to be sterilized is provided therein, and an outer peripheral surface (2a) and a bottom surface (2b) of the container arranged in the accommodation space are provided. ) Is formed of a dielectric (10, 11), and the opposing electrodes (5 and / or 6) are opposed to at least one of the outer peripheral surface and the bottom surface of the container with the dielectric interposed therebetween. A treatment tank (3) for atmospheric pressure plasma sterilization provided, wherein a protective layer is provided outside the counter electrode.
[0042]
Any of these treatment tanks can be suitably used for the sterilization apparatus of the present invention. However, the use of these treatment tanks is not limited to the simultaneous sterilization of the inner and outer surfaces of the container, and can be used when only the inner or outer surface of the container is sterilized alone.
[0043]
In the sterilization method and apparatus of the present invention, each counter electrode does not necessarily need to completely cover the outer peripheral surface or the bottom surface of the container, and a portion of the container that is not covered by the counter electrode may remain. However, it is desirable that the counter electrode is completely covered with the dielectric material as viewed from the discharge electrode. In other words, it is desirable that a dielectric is always sandwiched between the discharge electrode and the counter electrode.
[0044]
In the present invention, the outer surface of the container means a surface exposed to the outside of the container, the outer peripheral surface means a surface of the outer surface of the container which is directed to the side of the container, and the bottom surface is the container of the outer surface of the container. Means the side facing the bottom side of the
[0045]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows a sterilization apparatus according to one embodiment of the present invention. The sterilization apparatus 1 is provided with a storage space S for a container 2 to be sterilized therein, and a processing tank in which the inner surface covering the outer peripheral surface 2a and the bottom surface 2b of the container 2 disposed in the storage space S is made of a dielectric material. 3, a discharge electrode 4 that can be inserted into the container 2 disposed in the accommodation space S, and an outer peripheral counter electrode 5 provided so as to surround the outer peripheral surface 2a of the container 2 with the dielectric of the processing tank 3 interposed therebetween. A bottom facing electrode 6 provided to face the bottom surface 2b of the container 2 with the dielectric of the processing tank 3 interposed therebetween; a gas introduction device 7 serving as a gas introduction means for introducing gas into the storage space S; And a pulse power supply 8 as high voltage pulse applying means for applying a high voltage pulse between the outer electrode 4 and the outer peripheral counter electrode 5 and the bottom counter electrode 6. The container 2 only needs to be made of various materials other than metal. Here, as an example, an opening 2c is provided at the upper end like a PET bottle, and a neck 2d is provided following the opening 2c. It is assumed that a bottle-shaped container is used as the container 2.
[0046]
The processing tank 3 includes a stage 10 for supporting the container 2 from below, a cylindrical tubular body 11 placed on the stage 10, and a lid 12 as a lid. The stage 10, the cylindrical body 11, and the lid 12 are all made of a dielectric material. The outer peripheral counter electrode 5 is arranged on the outer periphery of the cylindrical body 11 and the bottom counter electrode 6 is arranged on the lower surface of the stage 10 in close contact with each other, thereby constituting a part of the processing tank 3.
[0047]
Various dielectric materials such as acrylic resin, ceramics, polycarbonate, polyvinyl chloride, and the like may be used as the dielectric constituting the stage 10 and the like. However, in order to observe a discharge phenomenon occurring in the treatment tank 3, it is desirable that at least the cylindrical body 11 has a light transmitting property enough to observe the discharge phenomenon. For example, the tubular body 11 may be made of a transparent acrylic resin. The stage 10 may be provided with a light transmitting property instead of or in addition to the cylindrical body 11.
[0048]
The diameter of the cylindrical body 11 may be a minimum size capable of accommodating the container 2 with some margin added. If the diameter of the tubular body 11 is made larger than necessary, the distance between the discharge electrode 4 and the outer peripheral counter electrode 5 may be unnecessarily increased, and the stability of the discharge phenomenon may be impaired. The thicknesses of the stage 10 and the cylindrical body 11 may be appropriately changed within a range in which a stable discharge is generated between the discharge electrode 4 and the counter electrodes 5 and 6. For example, when the stage 10 and the cylindrical body 11 are made of a transparent acrylic resin, their thickness is preferably set in a range of 0.5 mm to 40 mm.
[0049]
The stage 10 and the lid 12 are formed larger than the cylindrical body 11 so as to reliably cover the lower and upper openings 11a and 11b of the cylindrical body 11, respectively. Stage 10 is further supported by suitable support means. The stage 10 and the cylindrical body 11 may be integrated, or may be separable. The lid 12 may be attached to the tubular body 11 so as to be openable and closable, or may be separated from the tubular body 11 and driven to open and close the tubular body 11 by an appropriate driving means. The lid 12 does not need to completely close the opening 11b, but may be any as long as the opening 11b can be narrowed so as to prevent gas diffusion from the storage space S. In FIG. 1, the cover 12 is provided with holes 12a and 12b through which the discharge electrode 4 and the gas nozzles 15 and 16 of the gas introduction device 7 pass. The vent holes 12a and 12b are formed to be slightly larger, and thus function as gas vent holes for discharging the gas to be replaced out of the processing tank 3. A hole for venting gas may be provided separately from the vent holes 12a and 12b.
[0050]
Further, as support means for supporting the container 2 on the stage 10 in the processing tank 3 such that a gap 19 through which gas flows is formed between the bottom surface 2b of the container 2 and the upper surface (inner bottom surface) 10a of the stage 10. Are arranged at appropriate intervals in the circumferential direction of the container 2. The spacer 18 is made of a dielectric material like the stage 10. It is desirable that the number and size of the spacers 18 be determined such that a gap 19 is provided between the bottom surface 2b of the container 2 and the upper surface 10a of the stage 10 so that the gas can sufficiently flow around while the container 2 is stably supported. The appropriate range of the gap 19 is desirably in the range of 0.1 mm to 20 mm. The spacer 18 may be configured as a separate member from the stage 10, or may be provided integrally with the stage 10.
[0051]
The discharge electrode 4 is formed by molding a conductive material such as stainless steel into a rod-like member having a thickness that can be inserted into the container 2. The discharge electrode 4 is connected to the positive electrode of the pulse power supply 8 and functions as a positive electrode. The negative electrode of the pulse power source 8, the outer peripheral counter electrode 5, and the bottom counter electrode 6 are all grounded. In order to reduce the distance between the discharge electrode 4 and the outer peripheral counter electrode 5 to generate a discharge phenomenon with as small an energy as possible, it is desirable to set the thickness of the discharge electrode 4 as large as possible within a range that can be inserted into the container 2. The length of the discharge electrode 4 may be determined so that it can be inserted into the container 2 at a necessary and sufficient depth. It is preferable that the insertion amount (length) of the discharge electrode 4 into the container 2 is set in a range of 1/10 to 9/10 of the total height of the container 2. If the insertion amount of the discharge electrode 4 is less than 1/10 of the total height of the container 2, the discharge amount in the container 2 is insufficient, and if the insertion amount exceeds 9/10, the discharge concentrates on the bottom facing electrode 6 side and the container The bottom side of the container 2 may be thermally deformed, and a sufficient sterilizing effect may not be obtained on the outer surface 2a side of the container 2.
[0052]
FIG. 2A shows an enlarged part of the discharge electrode 4, and FIG. 2B shows an enlarged part of the discharge electrode 4. As is apparent from these figures, a single spiral thread 4a is formed over the entire range of insertion of the discharge electrode 4 into the container 2, whereby almost the entire insertion range of the discharge electrode 4 is formed. Irregularities are provided. The reason why the unevenness is provided in this manner is to cause the discharge to occur uniformly over substantially the entire length of the insertion range of the discharge electrode 4 into the container 2 without concentrating the discharge phenomenon at the tip of the discharge electrode 4. In other words, since the electric field is concentrated at the sharp portion of the discharge electrode 4 to cause a discharge, the unevenness is provided evenly throughout the insertion range of the discharge electrode 4 into the container 2 so that the screw is not limited to the tip of the discharge electrode 4. Discharge can be uniformly generated from the top of the crest 10 so that equal sterilization action can be generated in each part of the container 2. It is desirable that the tip 4b of the discharge electrode 4 be formed as flat as possible to avoid concentration of discharge at this portion.
[0053]
The pitch p of the thread 4a formed on the discharge electrode 4 is preferably in the range of 0.01 mm to 10 mm, and more preferably in the range of 0.1 mm to 5 mm. When the pitch p is less than 0.01 mm, there is a possibility that a uniform discharge may not be obtained because the interval between the irregularities is too small. On the other hand, when the pitch p is more than 10 mm, the protrusions are sparsely distributed and the discharge density is reduced. Decrease. The apex angle θ of the thread 4a is preferably in the range of 5 ° to 60 °, and more preferably in the range of 10 ° to 45 °. If the apex angle θ is less than 5 °, the strength of the thread 4a may be insufficient, and if the apex angle θ exceeds 60 °, the discharge from the top of the thread 4a may be weakened.
[0054]
Returning to FIG. 1, the outer peripheral counter electrode 5 is formed in a cylindrical shape surrounding the outer periphery of the cylindrical body 11 over the entire periphery. The upper end of the outer peripheral counter electrode 5 is higher than the container 2 arranged in the accommodation space S and lower than the upper end of the cylindrical body 11. The lower end of the outer peripheral counter electrode 5 is located at the same height as the upper surface of the stage 10. However, the lower end of the outer peripheral counter electrode 5 may be located at a position slightly higher than the bottom surface 2b of the container 2.
[0055]
The outer peripheral counter electrode 5 is formed by winding a plate or net made of a conductive material (for example, metal such as stainless steel) around the outer periphery of the tubular body 11. The outer peripheral counter electrode 5 desirably has translucency so that the discharge phenomenon inside the processing tank 3 can be observed. For example, if the outer peripheral counter electrode 5 is formed of a metal mesh as schematically shown in the right corner of FIG. 1, the outer peripheral counter electrode 5 is provided with a light transmissivity enough to allow a discharge phenomenon to be confirmed through the mesh. be able to.
[0056]
The outer peripheral counter electrode 5 may be formed by depositing a conductive material on the outer periphery of the cylindrical body 11. According to the vapor deposition, the electrode 5 can be configured to be thin, and the outer peripheral counter electrode 5 can be provided with a light transmissivity enough to observe a discharge phenomenon inside the processing tank 3. As a material to be deposited for forming the electrode 5, a metal material such as copper, aluminum, gold, and platinum, and other various conductive materials can be used. Instead of vapor deposition, a conductive paint may be applied to the outer periphery of the cylindrical body 11 to form the outer peripheral counter electrode 5.
[0057]
The bottom facing electrode 6 can also be provided on the lower surface of the stage 10 in the same manner as the outer periphery facing electrode 5. That is, a plate or net made of a conductive material is arranged on the lower surface of the stage 10, a conductive material is deposited on the lower surface of the stage 10, or a conductive paint is applied on the lower surface of the stage 10 to form the bottom facing electrode 6. Can be formed. As shown in FIG. 3A, the outer periphery 6a of the bottom facing electrode 6 is located outside the outer periphery facing electrode 5, or the outer periphery 6a is located at the outer periphery facing electrode 5 as shown in FIG. It is desirable to provide them so as to match. As shown in FIG. 3C, when the outer periphery 6 a of the bottom facing electrode 6 is located inside the outer periphery facing electrode 5, discharge concentrates between the discharge electrode 4 and the outer periphery 6 a of the bottom facing electrode 6. However, there is a possibility that sufficient discharge does not occur between the discharge electrode 4 and the outer peripheral counter electrode 5. When the stage 10 has a light-transmitting property, a light-transmitting property may be given to the bottom facing electrode 6 so that the discharge phenomenon inside the processing tank 3 can be observed from the bottom side of the processing tank 3.
[0058]
As shown in FIG. 1, the gas introduction device 7 includes the above-described gas nozzles 15 and 16 and a gas supply source 17 that supplies a predetermined gas to the nozzles 15 and 16. The first gas nozzle 15 disposed on the center side of the processing tank 3 is inserted into the processing tank 3 through the hole 12 a of the lid 12 similarly to the discharge electrode 4, and the tip thereof is inserted into the container 2. You. Thus, the gas supply source 17 and the first gas nozzle 15 constitute an inside introduction unit. On the other hand, two second gas nozzles 16 arranged on the outer peripheral side of the lid 12 are inserted into the processing tank 3 through the hole 12 b of the lid 12. Further, each tip of the second gas nozzle 16 is directed to the outer surface side of the container 2. Therefore, the gas supply source 17 and the second gas nozzle 16 constitute an outside introduction unit. The gas supply source 17 supplies a predetermined gas contributing to the generation of the atmospheric pressure plasma to the gas nozzles 15 and 16. The supply flow rate of the gas from the gas supply source 17 can be controlled by a flow control valve (not shown).
[0059]
As the gas supplied from the gas supply source 17, at least one gas selected from the group consisting of oxygen, hydrogen, nitrogen, carbon dioxide, air, argon, and helium can be used. These gases are preferable because the dielectric breakdown voltage when a high voltage pulse is applied can be reduced. Two or more gases selected from the above group may be mixed and supplied to the gas nozzles 15 and 16. In addition, various gases may be used as long as they contribute to plasma generation.
[0060]
As the pulse power supply 8, a power supply capable of applying a high voltage pulse having a voltage of 38 to 80 kV and a frequency of 100 to 3000 Hz (or pps) between the discharge electrode 4 and the counter electrodes 5 and 6 is used. However, the performance of the pulse power supply 8 may be appropriately changed according to the size of the container 2 to be sterilized and the capacity of the processing tank 3.
[0061]
The disinfection device 1 is provided with a swimsuit device for attaching moisture to the inner and outer surfaces of the container 2 to be disinfected as an incidental facility. FIG. 4 shows an example of the swimsuit device. The swimsuit device 30 in FIG. 4 includes a pump 31 that pumps up and sends out water from a tank (not shown), a first spray nozzle 32 that sprays the water sent from the pump 31 toward the inside of the container 2, and a pump 31. There are provided second spray nozzles 33... 33 for spraying the sent moisture toward the outer surface of the container 2. The spray nozzles 32 and 33 need to be provided so that moisture is uniformly attached to the inner and outer surfaces of the container 2.
[0062]
The water may be supplied to such an extent that clouding occurs on the inner and outer surfaces of the container 2. As the water supplied from the pump 31, pure water containing no impurities is suitable. When pure water is used, the supply amount may be such that water particles having a diameter of about several μm adhere to the inner and outer surfaces of the container 2. For example, when the container 2 is a resin bottle having a capacity of 500 mL (milliliter), pure water in a range of 0.01 g to 10 g may be supplied to both the inner surface and the outer surface of the container 2. Instead of pure water, an organic aqueous solution containing ethanol or acetone, or an inorganic aqueous solution containing an electrolyte or the like may be sprayed toward the container 2. Water may be sprayed using a nebulizer instead of the nozzles 32 and 33.
[0063]
Next, a method of sterilizing the container 2 using the sterilizing apparatus 1 will be described. First, moisture is attached to the inner and outer surfaces of the container 2 by the swimwear device 30 of FIG. 4 prior to sterilization. The appropriate amount of water supply is as described above. After the application of the water, the container 2 is stored in the storage space S from the opening 11b of the cylindrical body 11 of the processing tank 3 as shown in FIG. And the opening 11 b is closed, and the discharge electrode 4 and the gas nozzles 15 and 16 are inserted into the processing tank 3. Thereafter, as shown in FIG. 5C, gas is introduced into the processing tank 3 from the gas nozzles 15 and 16. At this time, gas is introduced from the first gas nozzle 15 into the inside of the container 2, gas is introduced from the second gas nozzle 16 to the outside of the container 2, and the air that has stayed inside and outside of the container 2 until now is covered by the lid 12. Purge holes 12a and 12b are sequentially purged. Thereby, the gas is replaced inside and outside the container 2 in the storage space S. Further, since the opening 11b of the processing tank 3 is narrowed by the lid 12, diffusion of the replaced gas to the outside of the processing tank 3 can be suppressed, and the gas can be sufficiently stored in the processing tank 3.
[0064]
The flow rate of the gas before the application of the high-voltage pulse may be appropriately determined. For example, when the container 2 is a resin bottle having a capacity of 500 mL, the gas flow rate from the first gas nozzle 15 is set to 0.1. 1 L / min. ~ 1000 L / min. , More preferably 10 L / min. ~ 400 L / min. , The gas flow rate from the second gas nozzle 16 is set to 0.1 L / min. ~ 1000 L / min. , More preferably 10 L / min. ~ 400 L / min. It is good to set each in the range of. Further, the gas supply time is preferably set in the range of 0.05 seconds to 60 seconds, more preferably 0.1 seconds to 10 seconds, for both the first gas nozzle 15 and the second gas nozzle 16.
[0065]
After the air inside the processing tank 3 is replaced with the gas from the gas nozzles 15 and 16 as described above, the air is discharged between the discharge electrode 4 and the counter electrodes 5 and 6 at normal temperature and normal pressure as shown in FIG. A high voltage pulse is applied to generate a discharge between the discharge electrode 4 and the counter electrodes 5 and 6, thereby ionizing gas existing inside and outside the container 2 to generate atmospheric pressure plasma. Thereby, the inner and outer surfaces of the container 2 are sterilized at the same time. The range of the high voltage pulse applied from the pulse power supply 8 is as described above. The time for which the application of the high voltage pulse is continued depends on the capacity of the container 2, but may be about 0.1 to 60 seconds, more preferably about 1 to 10 seconds.
[0066]
It is desirable that the gas flow rate from the gas nozzles 15 and 16 during the discharge is smaller than the gas flow rate before the start of the application of the high voltage pulse. Before the application of the high-voltage pulse, the gas flow rate is set large to complete the replacement of the gas as early as possible.However, if the gas is supplied at such a large flow rate during the application of the high-voltage pulse, discharge becomes unnecessary. This is because it is difficult to uniformly generate a sterilizing effect on the inner and outer surfaces of the container 2. The gas flow rate during the application of the high-voltage pulse is such that the plasma is not uniformly generated at a specific location between the discharge electrode 4 and the counter electrodes 5 and 6, and the plasma is maintained uniformly over the entire circumference of the discharge electrode 4. It is desirable to set the flow rate. For example, in the case of a resin bottle having a capacity of 500 mL, the gas flow rate from the first gas nozzle 15 is set to 0.1 L / min. -10 L / min. , The gas flow rate from the second gas nozzle 16 is set to 0.1 L / min. -10 L / min. It is good to set each in the range of. When the application time of the high voltage pulse is sufficiently short, the flow rate of the gas may be set to 0 during application, that is, the introduction of the gas may be stopped.
[0067]
After sterilizing the container 2 as described above, the discharge electrode 4, the gas nozzles 15, 16 and the lid 12 may be removed and the container 2 may be taken out of the processing tank 3.
[0068]
The embodiments described above are merely examples of the present invention, and the present invention may be implemented in various forms. For example, as for the processing tank, as shown in FIG. 6, the processing tank 3 may be turned upside down, and the container 2 may be taken in and out from below.
[0069]
The support structure of the container 2 in the processing tank 3 may be implemented in a form as shown in FIGS. 7 to 9, for example. In the embodiment shown in FIGS. 7 and 8, a recess 10 b larger in the radial direction than the container 2 is formed on the upper surface 10 a of the stage 10, and a plurality of ribs 10 c ... 10 c supporting the bottom surface 2 b of the container 2 are formed in the recess 10 b. The ribs 10c are made to function as supporting means by providing them at intervals in the direction. In this case, as shown in FIG. 7, a gap 19 is formed between the bottom surface of the concave portion 10b constituting the inner bottom surface of the processing tank 3 and the bottom surface 2b of the container 2. Then, gas is introduced from the outer periphery of the concave portion 10b into the gap 19 as shown by the arrow G.
[0070]
In the embodiment shown in FIG. 9, the leg 21 is provided on the back side of the net 20 having a diameter larger than that of the container 2 to constitute the support means. In this case, the leg 21 is placed on the upper surface 10a of the stage 10, and the bottom surface 2b of the container 2 is placed on the net 20, so that the gap 19 is formed between the bottom surface 2b of the container 2 and the inner bottom surface 10a of the processing tank 3. Occurs. Then, the gas is introduced into the gap 19 through the net 20 as shown by the arrow G. The legs 21 may be provided at intervals in the circumferential direction, or may be ring-shaped.
[0071]
In the embodiment shown in FIG. 10, the processing tank 3 is turned upside down and supported by a claw member 22 capable of gripping the neck 2 d of the container 2 and a leg 23 supporting the claw member 22 on the inner surface 12 c of the lid 12. Means. In this case, gas is introduced into the gap 19 between the inner surface 12c of the lid 12 constituting the inner bottom surface of the processing tank 3 and the container 2 from the gap of the claw member 22 or the leg 23 as shown by the arrow G. Thereby, the top surface surrounding the opening 2c can be brought into contact with the gas.
[0072]
If a sufficient gap is formed between the bottom surface 2b of the container 2 and the inner bottom surface of the processing tank 3 by providing the bottom surface 2b of the container 2 with irregularities such as petaloid, for example, The means may be omitted.
[0073]
FIG. 11 shows a protective layer 25 covering the outer peripheral counter electrode 5 and the bottom counter electrode 6 on the outer side of the cylindrical body 11 of the processing tank 3 and on the lower surface side of the stage 10 in order to protect the outer peripheral counter electrode 5 and the bottom counter electrode 6. , 26 are provided. It is desirable that these protective layers 25 and 26 be made of a dielectric material like the cylindrical body 11 and the stage 10. Further, in order to make it possible to observe a discharge phenomenon inside the processing tank 3, it is desirable that these protective layers 25 and 26 are also provided with a light transmitting property. Note that only one of the protective layers 25 and 26 may be provided.
[0074]
The discharge electrode 4 is not limited to one having the thread 4a shown in FIG. For example, as shown in FIG. 12, the surface of the discharge electrode 4 may be provided with irregularities by repeatedly providing a plurality of disc-shaped electrode plates 4c on the shaft 4b at a constant pitch p.
[0075]
Further, the insertion range of the discharge electrode 4 into the container 2 may be formed in a shape along the inner peripheral surface of the container 2. For example, as shown in FIG. 13, when the inner peripheral surface 2 e of the container 2 is formed in a tapered shape that gradually expands toward the opening 2 c, the outer periphery of the discharge electrode 4 follows the inner peripheral surface 2 e of the container 2. It may be gradually enlarged.
[0076]
The discharge electrode 4 is not limited to a rod or shaft. For example, as shown in FIG. 14, when the container 2 is a bowl or bowl type whose opening portion is sufficiently large in diameter compared to its depth, the discharge electrode 4 is formed in a ring shape and this is horizontally placed on the container 2. It is also possible to insert in. 13 and 14, the outer circumference of the discharge electrode 4 is formed in a spiral shape, but these discharge electrodes 4 can also be modified as shown in FIG.
[0077]
As shown in FIG. 4, the swimwear device 30 for the inner and outer surfaces of the container 2 is not limited to a device provided separately from the treatment tank 3 of the sterilization device 1. For example, as shown in FIG. 15, a tank 35 for storing water is provided between the gas supply source 17 and the processing tank 3, and the gas sent from the gas supply source 17 is once discharged into the water of the tank 35, and By collecting the gas above the liquid level and guiding it to the gas nozzles 15 and 16 of the processing tank 3, moisture may be attached to the inside and outside of the container 2 at the same time as the replacement of the gas in the processing tank 3. In this case, however, it is necessary to insert the discharge electrode 4 after gas replacement so that moisture does not adhere to the discharge electrode 4.
[0078]
As shown in FIG. 16, by disposing the discharge electrode 4 coaxially inside the first gas nozzle 15 for introducing the gas into the container 2, the gas can be introduced into the container 2 from around the discharge electrode 4. You may make it discharge | release. In this case, the first gas nozzle 15 may be attached to the lid 12 or may be supported by an appropriate means other than the lid 12. According to such a configuration, the discharge electrode 4 and the first gas nozzle 15 can be easily inserted into the inside of the container 2, which is particularly advantageous when the opening of the container 2 is narrow. In addition, since both the discharge electrode 4 and the gas nozzle 15 can be arranged on the center line of the container 2, the distance between the discharge electrode 4 and the outer peripheral counter electrode 5 is maintained equal in the entire circumference of the container 2, and the center inside the container 2 The gas can be evenly diffused from the line to the periphery to prevent the gas distribution in the container 2 from being biased.
[0079]
In addition, the present invention can be implemented in an appropriate form. The container is not limited to a resin container such as a PET bottle, and can be included in the sterilization target of the present invention as long as the container is not made of a conductive material. In the present invention, in order to enhance the sterilizing effect, it is desirable that moisture be attached to the inner and outer surfaces of the container while introducing the gas to the inner and outer surfaces of the container. However, when the required level of the sterilizing effect is low, a sufficient sterilizing effect may be obtained even if the adhesion of moisture is omitted. The cylindrical body of the processing tank is not limited to a cylindrical shape, and may have a polygonal cross section. A plurality of discharge electrodes may be provided.
[0080]
【Example】
The sterilizing apparatus of the above-described embodiment was manufactured, and its sterilizing effect was evaluated. The container to be sterilized was a PET bottle with a capacity of 500 ml. The sterilization operation was as follows.
[0081]
(Bottle for sterilization evaluation)
(1) Inner surface sterilization evaluation bottle
A predetermined amount of spores of Bacillus subtilis or Aspergillus niger was uniformly adhered to the inner surface of the PET bottle to prepare a bottle for inner surface sterilization evaluation.
(2) Bottle for external sterilization evaluation
A predetermined amount of the above-mentioned spores was attached to the outer surface mouth of the PET bottle, that is, the screw portion, the outer surface body, and the outer surface bottom at 10 places to obtain an outer surface sterilization evaluation bottle.
[0082]
(Basic sterilization conditions)
(1) Water adhesion conditions
Using the apparatus shown in FIG. 4, water was adhered only to the inner surface of the bottle for sterilization evaluation to a degree of cloudiness.
(2) Discharge conditions
A bottle for sterilization with water adhered thereto was installed in the apparatus of FIG. 1 and the air in the bottle was replaced with a mixed gas of argon and nitrogen, and then a high-voltage pulse was applied under the following conditions.
Replacement gas: A mixed gas of 5% argon and 95% nitrogen was used at a volume ratio of 0.5% for 120 seconds at a flow rate of 120 L / min.
Discharge electrode: A stainless steel spiral electrode having a diameter of 4 mm was used and placed 50 mm above the bottom of the bottle.
Cylindrical body: Acrylic cylinder with an inner diameter of 78 mm and a thickness of 5 mm
Stage: 7mm thick acrylic plate
Lid: 7 mm thick acrylic plate with 20 mm discharge electrode insertion hole and 6 mm outer gas introduction holes
Outer peripheral counter electrode: A 400 angstrom aluminum layer was deposited on the entire outer surface except for 5 mm from the upper and lower ends of the cylindrical body.
Discharge gas: A mixed gas having the same composition as the replacement gas was used and introduced into the inner surface of the bottle at a flow rate of 5 L / min.
Pulse application conditions: voltage 65 kV, frequency 2500 Hz, discharge time 30 seconds or less
[0083]
(Culture method)
After the discharge, the sterilization evaluation bottle was taken out of the apparatus, and the sterilization effect was evaluated by the following method.
(1) Inner surface sterilization evaluation
Approximately 100 ml of tryptoise bouillon liquid medium was immediately poured into the bottle, and a cap that had been sterilized in advance was shaken sufficiently, followed by culturing under the following conditions.
Bacillus subtilis: 35 ° C, 10 days
Aspergillus niger: 25 ° C, 10 days
(2) External surface sterilization evaluation
The mouth, trunk and bottom of the inoculated bacteria were cut off, transferred to a sterilized beaker, poured into an agar medium, and cultured under the following conditions.
Bacillus subtilis: standard agar medium, 35 ° C, 10 days
Aspergillus niger: Potato dextrose agar medium, 25 ° C, 10 days
After the culture, the bactericidal effect D value was calculated from the following equation 1.
(Equation 1)
Bactericidal effect D value = -log (viable bacterial count / initial bacterial count) Formula 1
[0084]
(Example 1)
In addition to the basic conditions, a sterilization test was performed by placing a copper plate having a diameter of 90 mm in close contact with the lower surface of the stage and placing a bottom facing electrode, and the results of the sterilization effect D value are shown in Table 1.
(Example 2)
In addition to Example 1, a mixed gas of 5% by volume of argon and 95% of nitrogen was introduced at a flow rate of 120 L / min for 0.5 seconds as a replacement gas on the outer surface of the bottle for 0.5 second. A sterilization test was performed by introducing a gas having the same composition at a flow rate of 5 L / min, and the results are shown in Table 1.
(Example 3)
In addition to Example 1, water was adhered to the outer surface of the bottle to a degree of cloudiness using the apparatus shown in FIG. 4, and a sterilization test was performed. The results are shown in Table 1.
(Example 4)
In addition to Example 2, water was adhered to the outer surface of the bottle to a degree of cloudiness using the apparatus shown in FIG. 4 to perform a sterilization test. The results are shown in Table 1.
(Example 5)
In addition to the basic conditions, a mixed gas of 5% by volume and 95% of nitrogen by volume as a replacement gas on the outer surface of the bottle is introduced at a flow rate of 120 L / min for 0.5 seconds, and the same discharge gas as the replacement gas on the outer surface of the bottle is used. A sterilization test was conducted by introducing a gas having a composition at a flow rate of 5 L / min. The results are shown in Table 1.
(Example 6)
In addition to Example 5, water was adhered to the outer surface of the bottle to a degree of cloudiness using the apparatus shown in FIG. 4, and a sterilization test was performed. The results are shown in Table 1.
(Example 7)
In addition to the basic conditions, a sterilization test was performed by using the apparatus shown in FIG. 4 to attach water to the outer surface of the bottle to a degree of cloudiness, and the results are shown in Table 1.
(Example 8)
A sterilization test was performed in the same manner as in Example 4 except that the discharge electrode was a stainless steel rod having a diameter of 4 mm, and the results are shown in Table 1.
(Comparative example)
A sterilization test was performed according to the basic conditions, and the results are shown in Table 1.
[0085]
[Table 1]

[0086]
【The invention's effect】
As described above, according to the present invention, atmospheric pressure plasma is generated inside and outside the container by applying a high voltage pulse between the discharge electrode and the counter electrode, and the plasma gas and the inner surface of the container are generated. By contacting the outer surfaces, those surfaces can be simultaneously and efficiently sterilized.
[Brief description of the drawings]
FIG. 1 is a partially cutaway sectional view showing a main part of a sterilization apparatus according to one embodiment of the present invention.
FIG. 2 is a diagram showing irregularities provided on a discharge electrode.
FIG. 3 is a diagram showing a relationship between an outer peripheral counter electrode and a bottom counter electrode.
FIG. 4 is a view showing a swimsuit device provided as an auxiliary facility of the sterilizing device.
FIG. 5 is a view showing a sterilization procedure using the sterilization apparatus of FIG. 1;
FIG. 6 is a view showing another embodiment of the processing tank.
FIG. 7 is a view showing another embodiment of the support means.
FIG. 8 is a view showing a state in which the stage in FIG. 7 is viewed from a direction of an arrow VIII in FIG. 7;
FIG. 9 is a view showing still another embodiment of the support means.
FIG. 10 is a diagram showing an embodiment of a support means for gripping the neck of the container.
FIG. 11 is a diagram showing an embodiment in which a protective layer is provided outside the outer peripheral counter electrode and the bottom counter electrode.
FIG. 12 is a view showing another embodiment of a discharge electrode.
FIG. 13 is a view showing still another embodiment of the discharge electrode.
FIG. 14 is a diagram showing an embodiment in which discharge electrodes are formed in a ring shape.
FIG. 15 is a view showing another embodiment of a swimsuit device.
FIG. 16 is a view showing another embodiment of a nozzle for introducing a gas into a container.
[Explanation of symbols]
1 Sterilizer
2 containers
2a Outer surface
2b bottom
2d neck
2e inner surface
3 Processing tank
4 discharge electrode
4a thread
4b axis
4c disk
5 Peripheral counter electrode
6 Bottom facing electrode
6a Outer circumference of bottom facing electrode
7 Gas introduction device (gas introduction means)
8 pulse power supply (high voltage pulse applying means)
10 stages
10c rib (supporting means)
11 Cylindrical body
11a, 11b opening
11d Upper cylindrical body
11e Lower cylindrical body
12 lid plate
15 First gas nozzle
16 Second gas nozzle
17 Gas supply source
18 spacer (supporting means)
19 gap
20 net (supporting means)
21 Legs (supporting means)
22 Claw members (supporting means)
23 legs (supporting means)
25, 26 protective layer
30 Swimsuit equipment
32, 33 spray nozzle
35 tank

Claims (39)

A container to be sterilized having an opening is disposed in a storage space in a processing tank surrounded by a dielectric at least on an inner surface side, and an outer peripheral surface and a bottom surface of the container are covered with the dielectric, and the opening of the container is opened. A discharge electrode is inserted from the portion, the outer peripheral surface of the container is surrounded by an outer peripheral counter electrode with the dielectric interposed therebetween, and the discharge electrode is placed in a state where the bottom surface of the container is opposed to the bottom electrode with the dielectric interposed therebetween. Simultaneously sterilizing the inner and outer surfaces of the container by applying a high-voltage pulse between the electrode and the outer peripheral counter electrode and the bottom counter electrode under normal temperature and normal pressure to generate atmospheric plasma inside and outside the container. A method for sterilizing a container, comprising: The sterilization method according to claim 1, wherein a predetermined gas is introduced into and out of the container disposed in the storage space. The sterilization method according to claim 1, wherein moisture is attached to an inner surface and an outer surface of the container before the application of the high voltage pulse. Prior to the application of the high voltage pulse, moisture is attached to the inner and outer surfaces of the container, and a predetermined gas is introduced into and from the container disposed in the storage space. The sterilization method according to claim 1. A container to be sterilized having an opening is disposed in a storage space in a processing tank surrounded by a dielectric at least on an inner surface side, and an outer peripheral surface and a bottom surface of the container are covered with the dielectric, and the opening of the container is opened. A discharge electrode is inserted from the part, the outer peripheral surface of the container is surrounded by an outer peripheral counter electrode with the dielectric interposed therebetween, and a predetermined gas is introduced into and out of the container disposed in the housing space, Applying a high-voltage pulse under normal temperature and normal pressure between the discharge electrode and the outer peripheral counter electrode to generate atmospheric pressure plasma inside and outside the container, thereby simultaneously sterilizing the inner surface and the outer surface of the container. Container sterilization method. The sterilization method according to claim 5, wherein moisture is attached to an inner surface and an outer surface of the container before the application of the high voltage pulse. A container to be sterilized having an opening is disposed in a storage space in a processing tank surrounded at least on the inner surface side by a dielectric, and the outer peripheral surface and the bottom surface of the container are covered with the dielectric, and the opening of the container is opened. The discharge electrode is inserted from the part, the outer peripheral surface of the container is surrounded by the outer peripheral counter electrode with the dielectric interposed therebetween, and in a state where moisture is attached to the inner surface and the outer surface of the container, the discharge electrode and the outer peripheral counter electrode are A sterilizing method for a container, wherein an inner surface and an outer surface of the container are sterilized simultaneously by applying a high-voltage pulse under normal temperature and normal pressure to generate atmospheric pressure plasma inside and outside the container. The sterilization method according to claim 2, wherein before and after the application of the high-voltage pulse, an opening for taking the container in and out of the processing tank is narrowed by a lid. The gas is introduced before the application of the high-voltage pulse, and the application flow rate of the gas is reduced during the application of the high-voltage pulse compared to before the application of the high-voltage pulse. 9. The sterilization method according to 8. In the storage space, the container is supported by a support unit having at least a surface formed of a dielectric so that a gap through which the gas flows is formed between the container and the inner bottom surface of the processing tank. The disinfection method according to claim 2, 4, 5, 6, 8, or 9, wherein The sterilization method according to claim 3, wherein the moisture is attached so that fogging occurs on the inner and outer surfaces of the container. The sterilization method according to any one of claims 1 to 4, wherein an outer periphery of the bottom surface facing electrode is made to coincide with the outer periphery facing electrode, or is located outside the outer periphery facing electrode. The sterilization method according to any one of claims 1 to 12, wherein irregularities are provided on a surface of an insertion range of the discharge electrode into the container over substantially the entire insertion range. The sterilization method according to claim 13, wherein the surface of the insertion area is formed in a spiral shape to provide the irregularities. A storage space for a container to be sterilized is provided therein, and an inner surface side that covers an outer peripheral surface and a bottom surface of the container disposed in the storage space is formed of a dielectric, and an outer peripheral surface of the container with the dielectric interposed therebetween. An outer peripheral counter electrode is provided so as to surround, and a processing tank provided with a bottom counter electrode so as to face the bottom surface of the container with the dielectric interposed therebetween,
A discharge electrode that can be inserted into the container disposed in the housing space,
The discharge electrode, a high voltage pulse applying means for applying a high voltage pulse between the outer peripheral counter electrode and the bottom counter electrode,
A container sterilization device comprising: The sterilization apparatus according to claim 15, further comprising a gas introduction unit that introduces a predetermined gas into and out of the container disposed in the storage space. The disinfection device according to claim 15, further comprising a swimsuit device for attaching moisture to an inner surface and an outer surface of the container. 16. The container according to claim 15, further comprising: gas introduction means for introducing a predetermined gas into and out of the container disposed in the storage space, and a swimsuit device for attaching moisture to an inner surface and an outer surface of the container. A sterilization apparatus according to claim 1. A storage space for a container to be sterilized is provided therein, and an inner surface side that covers an outer peripheral surface and a bottom surface of the container disposed in the storage space is formed of a dielectric, and an outer peripheral surface of the container with the dielectric interposed therebetween. A processing tank provided with an outer peripheral counter electrode so as to surround it,
A discharge electrode that can be inserted into the container disposed in the housing space,
Gas introduction means for introducing a predetermined gas into and out of the container arranged in the storage space,
High voltage pulse applying means for applying a high voltage pulse between the discharge electrode and the outer peripheral counter electrode,
A container sterilization device comprising: 20. The sterilizing apparatus according to claim 19, further comprising a swimwear device for attaching moisture to an inner surface and an outer surface of the container. A storage space for a container to be sterilized is provided therein, and an inner surface side that covers an outer peripheral surface and a bottom surface of the container disposed in the storage space is formed of a dielectric, and an outer peripheral surface of the container with the dielectric interposed therebetween. A processing tank provided with an outer peripheral counter electrode so as to surround it,
A discharge electrode that can be inserted into the container disposed in the housing space,
A swimsuit device for attaching moisture to the inner and outer surfaces of the container,
High voltage pulse applying means for applying a high voltage pulse between the discharge electrode and the outer peripheral counter electrode,
A container sterilization device comprising: 21. The sterilizer according to claim 16, wherein the processing tank is provided with an opening through which the container is put in and out, and an openable / closable lid for narrowing the opening. In the storage space, the container is supported such that a gap through which the gas flows between the container and the inner bottom surface of the processing tank is formed, and at least a surface of the container is provided with a support unit made of a dielectric. The sterilizer according to claim 16, 18, 19, 20 or 22, wherein: The sterilization apparatus according to any one of claims 15 to 18, wherein an outer periphery of the bottom-surface facing electrode coincides with the outer periphery-facing electrode or is located outside the outer periphery-facing electrode. The sterilizer according to any one of claims 15 to 24, wherein at least a part of the processing tank is provided with a light-transmitting property so that a discharge phenomenon occurring in the processing tank can be externally observed. . The sterilization apparatus according to any one of claims 15 to 24, wherein the outer peripheral counter electrode is metal-deposited on a dielectric constituting the treatment tank. The sterilizing apparatus according to claim 26, wherein the outer peripheral counter electrode deposited has a light-transmitting property. The sterilization apparatus according to any one of claims 15 to 25, wherein the outer peripheral counter electrode is formed by applying a conductive paint to a dielectric constituting the treatment tank. . The sterilizer according to any one of claims 15 to 28, wherein a protective layer is provided outside the outer peripheral counter electrode. The sterilization apparatus according to any one of claims 15 to 18, and 24, wherein the bottom facing electrode is metal-deposited on a dielectric constituting the treatment tank. 31. The sterilizer according to claim 30, wherein the deposited bottom facing electrode has a light transmitting property. The said bottom surface counter electrode is formed by apply | coating a conductive paint with respect to the dielectric material which comprises the said processing tank, The Claims any one of Claims 15-18 and 24 characterized by the above-mentioned. Sterilizer. The sterilization apparatus according to any one of claims 15 to 18, and 30 to 32, wherein a protective layer is provided outside the bottom facing electrode. The sterilization according to any one of claims 15 to 33, wherein the surface of the insertion range of the discharge electrode into the container is provided with irregularities over substantially the entire insertion range. apparatus. 35. The sterilizer according to claim 34, wherein the surface of the insertion area is formed in a spiral shape to provide the unevenness. The sterilizer according to any one of claims 15 to 35, wherein an insertion range of the discharge electrode into the container is formed in a shape along an inner peripheral surface of the container. A storage space for a container to be sterilized is provided inside, and an inner surface side that covers an outer peripheral surface and a bottom surface of the container disposed in the storage space is formed of a dielectric, and an outer peripheral surface of the container with the dielectric interposed therebetween. A treatment tank for atmospheric pressure plasma sterilization provided with a counter electrode so as to face at least one of the bottom surfaces, wherein the counter electrode is formed by metal deposition. Processing tank. A storage space for a container to be sterilized is provided inside, and an inner surface side that covers an outer peripheral surface and a bottom surface of the container disposed in the storage space is formed of a dielectric, and an outer peripheral surface of the container with the dielectric interposed therebetween. A treatment tank for atmospheric pressure plasma sterilization provided with a counter electrode so as to face at least one of the bottom surfaces, wherein the counter electrode is formed by applying a conductive paint to the dielectric. A processing tank for sterilization, characterized in that: A storage space for a container to be sterilized is provided inside, and an inner surface side that covers an outer peripheral surface and a bottom surface of the container disposed in the storage space is formed of a dielectric, and an outer peripheral surface of the container with the dielectric interposed therebetween. A processing tank for atmospheric pressure plasma sterilization provided with a counter electrode so as to face at least one of the bottom surfaces, for sterilization, wherein a protective layer is provided outside the counter electrode. Processing tank.

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