JP2005279042A - Method and device of sterilization - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To securely sterilize an object, to prevent the secondary contamination after sterilization, and to reduce the time and energy necessary for the treatment by a simple structure. <P>SOLUTION: The sterilization device 10 consists of a treatment chamber 20, a vacuum pump 22, and a microwave oscillator 24. The object 12 of sterilization is sealed inside a microwave-permeable bag 14 together with a small amount of hydrogen peroxide (including hydrogen peroxide water) 18. When the bag 14 is put into the treatment chamber 20 and the vacuum pump 22 is driven, the interior of the treatment chamber 20 is decompressed to a hardly dischargeable state, and the bag 14 is inflated with the difference in pressure between the interior and the exterior to be decompressed to an easily dischargeable state. At the time, when microwaves 32 oscillated from the microwave oscillator 24 are applied, the microwaves 32 converge in the bag 14. Then, the gas inside the bag 14 including hydrogen peroxide 18 becomes plasma state to generate active oxygen, so that the object of sterilization 12 is sterilized with the generated active oxygen. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a sterilization method and sterilizer for sterilizing medical instruments such as rubber stoppers, syringes, needles, scalpels and tweezers, hygiene products, consumables, equipment and food materials, packaging materials for aseptic packaging, and the like. The present invention relates to a sterilization method and sterilization apparatus using high frequency or microwave.

  Conventional sterilization methods are roughly classified into a method of heat sterilizing an object to be sterilized by heating with microwaves, and a method of sterilizing an object with active oxygen generated by converting hydrogen peroxide into plasma. Of these, the latter method can be sterilized at low temperatures, so it can sterilize medical instruments, sanitary products, consumables, equipment and food materials, packaging materials for aseptic packaging, etc. It is widely called plasma sterilization method. In the plasma sterilization method, an object to be sterilized is placed in a cavity (or treatment chamber) irradiated with a large volume of microwaves (or high frequency) together with hydrogen peroxide, and the entire interior of the cavity is discharged to perform sterilization.

  However, in the background art described above, in order to generate plasma by high frequency or microwave discharge, the entire inside of the cavity is discharged by atmospheric pressure using a special technique, or the whole inside of the cavity is easily discharged to a state where it can be easily discharged. It is necessary to reduce the pressure. For this reason, in the case of atmospheric pressure discharge, a special technique is required, and when the entire inside of the cavity is decompressed, there is a disadvantage that it takes time to evacuate. In any case, since the gas in the entire cavity needs to be turned into plasma, the output of the microwave (or high frequency) oscillator must be increased, which consumes a large amount of power energy. Furthermore, since packaging must be performed after the above-described sterilization treatment, there is a possibility that various bacteria may be mixed in the process.

  The present invention pays attention to the above points, and its purpose is to sterilize the object reliably while preventing the secondary contamination after sterilization while having a simple configuration, To provide a sterilization method and a sterilization apparatus capable of reducing energy.

  In order to achieve the above object, the sterilization apparatus of the present invention is packaged or stored together with a small amount of hydrogen peroxide (including hydrogen peroxide solution) in a bag-like sealing means having high-frequency or microwave permeability. A processing chamber for performing a sterilization process on the sterilized object, and evacuating the processing chamber to a state where it is impossible to discharge or difficult to discharge to expand the sealing means in the processing chamber by a differential pressure inside and outside, An evacuation unit for reducing the pressure inside the sealing unit to a state where it can be easily discharged, irradiating the processing chamber with a high frequency or microwave, and converting the gas containing hydrogen peroxide in the sealing unit into plasma, thereby sterilizing the object to be sterilized Irradiation means for generating active oxygen for the purpose is provided. One of the main forms is characterized in that the sealing means is a plastic bag or a composite bag made of plastic and other materials.

  The sterilization apparatus according to another invention has high-frequency or microwave permeability and is packaged together with a small amount of hydrogen peroxide (including hydrogen peroxide solution) in a sealing means whose pressure is reduced to a state where the inside is easily discharged. A processing chamber for performing sterilization processing on a sterilized object stored therein, the processing chamber in an atmospheric pressure state is irradiated with high frequency or microwave, and a gas containing hydrogen peroxide in the sealing means is turned into plasma, and the sterilization is performed. Irradiation means for generating active oxygen for sterilizing an object is provided. One of the main forms is characterized in that the sealing means is any one of a plastic bag, a composite bag made of plastic and other materials, or a container made of plastic or glass.

  In another form, the sealing means includes another exhaust means that enables exhaust in the seal means, or a valve or a partition wall that can inject hydrogen peroxide into a vacuum or under reduced pressure. To do. Yet another embodiment is characterized in that the pressure in the sealing means is 0.1 to 10 Torr. In still another embodiment, the sealing means includes at least one of a desiccant that absorbs water generated by decomposition of the hydrogen peroxide, or an oxygen scavenger that absorbs oxygen generated by the decomposition, and the sterilization object and Packaged or stored with hydrogen peroxide.

  In the sterilization method of the present invention, the sealing means that wraps or stores an object to be sterilized and a small amount of hydrogen peroxide (including hydrogen peroxide solution) in a sealing means that can transmit high frequency or microwave, and is placed in a processing chamber. In a state where the inside of the chamber is reduced to a state where it is easy to discharge, the processing chamber is made undischargeable or difficult to discharge, and the processing chamber is irradiated with the high frequency or microwave to contain hydrogen peroxide in the sealing means. Gas is turned into plasma to generate active oxygen, and the object to be sterilized is sterilized with the active oxygen. Alternatively, the object to be sterilized in the sealing means is sterilized using the sterilizer according to any one of claims 2 to 8. The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

  In the present invention, the inside of the sealing means in which the object to be sterilized and a small amount of hydrogen peroxide (including hydrogen peroxide solution) is packaged or stored is reduced to a state where it can be easily discharged, and the processing chamber in which the sealing means is placed cannot be discharged. In addition, after making it difficult to discharge, the processing chamber is irradiated with high frequency or microwave, and the gas containing hydrogen peroxide in the sealing means is turned into plasma to generate active oxygen. For this reason, the space for sterilization with active oxygen can be localized and limited, and reliable sterilization can be performed, and the processing time and energy required for irradiation can be greatly reduced. Further, since the sterilization process is performed after the object to be sterilized is sealed, the sterilized state is maintained until the sealing means is opened, and secondary contamination after sterilization can be prevented.

  Hereinafter, the best mode for carrying out the present invention will be described in detail based on examples.

  First, Embodiment 1 of the present invention will be described with reference to FIG. As shown in FIGS. 1A to 1C, a sterilization apparatus 10 according to the present embodiment includes a processing chamber (or chamber) 20 for performing sterilization processing on an object 12 to be sterilized individually wrapped by a bag 14, and the processing. The chamber 20 includes a vacuum pump 22 that evacuates and decompresses the chamber 20 to a state where discharge is difficult or difficult to discharge, and a microwave oscillator 24 that oscillates the microwave irradiated into the processing chamber 20. In addition to the object 12 to be sterilized, the bag 14 contains a small amount of hydrogen peroxide (or hydrogen peroxide solution) 18 and, if necessary, a desiccant 26 and an oxygen scavenger 28.

  Suitable examples of the sterilization object 12 include rubber stoppers, syringes, needles, medical instruments such as scalpels and tweezers, hygiene products, consumables, equipment and food materials, and packaging materials for aseptic packaging. Various other things that require processing are applicable. The bag 14 has only to have a property of transmitting microwaves, and for example, a plastic bag (including a composite bag of paper, cloth, and plastic) is preferable. Further, as will be described later, it is convenient that there is flexibility so that the bag 14 can be expanded by a differential pressure inside and outside the bag 14. Then, the sterilization object 12 and the like can be stored and sealed by a sealing means (not shown).

  The hydrogen peroxide 18 is usually injected directly into the bag 14, but may be impregnated into the cloth 16 as necessary, and the injection amount may be the volume of the bag 14 or the sterilization target 12. You may change suitably according to a kind. That is, when the volume of the inflated bag 14 is Vcc, hydrogen peroxide 18 of about 0.1 V μg to 30 V μg is injected. For example, if the bag 14 has a volume of 1 liter when inflated, about 0.1 mg of hydrogen peroxide 18 is injected. Moreover, what is necessary is just to adjust the usage-amount suitably according to a dilution degree, when using hydrogen peroxide solution. In addition, although the use of the cloth 16 is arbitrary, in the case of using it, it is convenient to use, for example, a non-woven fabric because there is no fear of carbonization. Such hydrogen peroxide 18 is gasified when the inside of the bag 14 is depressurized, and further converted into plasma by irradiation with microwaves to pass through an active oxygen state, and is finally decomposed into water and oxygen. The desiccant 26 and the oxygen scavenger 28 absorb water and oxygen generated from the hydrogen peroxide 18 and may be provided as necessary.

  Further, the processing chamber 20 includes a cavity for sterilizing the object 12 to be sterilized stored in the bag 14 and can be sealed by a door (not shown). Therefore, when the vacuum pump 22 is driven, the inside of the processing chamber 20 is evacuated, and the pressure is reduced to a decompressed state where discharge is impossible or difficult to discharge, that is, about 1 / 100,000 atm (0.0076 Torr). Further, as shown in FIG. 1C, an irradiation port 30 for irradiating the microwave 32 oscillated by the microwave oscillator 24 is provided on the wall surface of the processing chamber 20. As the vacuum pump 22 and the microwave oscillator 24 as described above, those having various known structures can be used.

  Next, the operation of this embodiment will be described. First, as shown in FIG. 1A, the sterilization object 12, a small amount of hydrogen peroxide 18 (or a cloth 16 impregnated with hydrogen peroxide 18), a desiccant 26, and an oxygen scavenger 28 are placed in the bag 14. Store and seal. Then, after the sealed bag 14 is placed in the processing chamber 20 as shown in FIG. 1B and the processing chamber 20 is sealed, the vacuum pump 22 is driven to evacuate the processing chamber 20. At this time, as described above, when the inside of the processing chamber 20 is difficult to discharge, that is, when the pressure is reduced to 1 / 100,000 atm or less, a pressure difference is generated inside and outside the bag 14, and the bag 14 is caused by the pressure difference. Inflate. As a result of the expansion, the inside of the bag 14 is easily discharged, that is, reduced to about 0.1 to 10 Torr, and the hydrogen peroxide 18 is gasified.

  In this state, as shown in FIG. 1C, when the microwave 32 oscillated from the microwave oscillator 24 is irradiated (injected) into the processing chamber 20 through the irradiation port 30, the inside of the processing chamber 20 is The microwave 32 is concentrated only in the microwave permeable bag 14 because it is in a state that is hardly discharged in a vacuum state. Since the inside of the bag 14 is decompressed so as to be easily discharged as described above, the gas in the bag 14 containing the hydrogen peroxide 18 is discharged and turned into plasma, and active oxygen is generated with high efficiency. Then, the sterilization object 12 in the bag 14 is sterilized by the generated active oxygen. Since water and oxygen generated from the hydrogen peroxide 18 are absorbed by the desiccant 26 and the deoxidizing material 28, respectively, there is no possibility that the sterilization target 12 is deteriorated or deteriorated by water or oxygen. When the sterilization processing is stored as described above, the inside of the processing chamber 20 is returned to the atmospheric pressure, and the bag 14 is taken out. At this time, since the object 12 to be sterilized is already packaged in the bag 14, secondary contamination such as contamination of bacteria by the packaging process after the completion of sterilization is reliably prevented, and the inside until the bag 14 is opened. The object 12 to be sterilized can be reliably kept in a sterilized state.

Thus, according to the first embodiment, there are the following effects.
(1) The object to be sterilized 12 and a small amount of hydrogen peroxide 18 are stored in a bag 14 for individual packaging and placed in a processing chamber 20, and the inside of the processing chamber 20 is depressurized to a state where it is not discharged by a vacuum pump 22. The bag 14 was inflated by the pressure difference between the inside and outside of the bag 14, and the inside of the bag 14 was depressurized so as to be easily discharged. For this reason, the space where the microwave 32 is irradiated to generate active oxygen can be localized and limited to the inside of the bag 14, and a reliable sterilization process can be performed, and the processing time and microwave irradiation energy can be reduced. Can do.
(2) Since the sterilization process is performed with the sterilization target object 12 placed in the bag 14 and sealed, the sterilization target object 12 is not exposed to the outside air after the process is completed, and secondary due to contamination with various germs. Contamination can be prevented.
(3) Since the desiccant 26 and the oxygen scavenger 28 are placed in the bag 14, alteration or deterioration of the sterilization target 12 due to water or oxygen generated from the hydrogen peroxide 18 can be prevented.

  Next, Embodiment 2 of the present invention will be described with reference to FIG. In addition, the same code | symbol shall be used for the component which is the same as that of Example 1 mentioned above, or respond | corresponds. The sterilization apparatus 50 according to the present embodiment includes a processing chamber 60 that performs a sterilization process on an object 52 to be sterilized stored in a container 54, and a microwave oscillator that oscillates microwaves that are irradiated into the processing chamber 60. 64. In addition to the object 52 to be sterilized, the container 54 stores a desiccant 26 and an oxygen scavenger 28 as required. The container 54 is easily discharged in a state (0.1 to 10 Torr). The pressure is reduced in advance by an exhaust means (not shown). A septum (or check valve) 56 for injecting a small amount of hydrogen peroxide 18 in a decompressed state is provided on the side surface of the container 54. As the sterilization object 52, the same one as in Example 1 described above can be applied, and the container 54 is made of a plastic or glass having microwave permeability, A material having pressure resistance is used so that it can withstand a decompressed state. Further, the processing chamber 60 is provided with an irradiation port 66 for irradiating a microwave oscillated from a microwave oscillator 64 in addition to a door 62 for opening and closing an opening for taking in and out the container 54.

  Next, the operation of this embodiment will be described. First, the object to be sterilized 52, the desiccant 26, and the oxygen scavenger 28 are housed and sealed in the container 54, and the inside of the container 54 is easily discharged by an exhaust means (not shown) (about 0.1 to 10 Torr). Reduce pressure until Then, after decompression, a small amount of hydrogen peroxide 18 is directly injected into the container 54 from the septum 56. The hydrogen peroxide 18 injected into the decompressed container 54 is gasified. In this embodiment, the hydrogen peroxide 18 is injected after the pressure in the container 54 is reduced. However, as in the first embodiment, the hydrogen peroxide 18 is injected into the container 54 and The pressure may be reduced by exhausting. Next, the container 54 in the state as described above is put into the processing chamber 60, the door 62 is closed, and the microwave oscillated from the microwave oscillator 64 is irradiated into the processing chamber 60 from the irradiation port 66. At this time, since the inside of the processing chamber 60 is in an atmospheric pressure state, it is not discharged, and the microwave energy is concentrated in the container 54 whose pressure is reduced to a predetermined pressure. Then, the gas in the container 54 containing the hydrogen peroxide 18 is discharged into plasma, and active oxygen is generated with high efficiency. Then, the sterilization target object 52 in the container 54 is sterilized by the generated active oxygen. The water and oxygen generated from the hydrogen peroxide 18 are absorbed by the desiccant 26 and the deoxidizing material 28, respectively. When the sterilization process is stored as described above, the door 62 is opened and the container 54 is taken out. According to the present embodiment, in addition to the effects of the first embodiment described above, it is not necessary to depressurize the inside of the processing chamber 60, so that the entire apparatus 50 can be reduced in size.

  Next, Embodiment 3 of the present invention will be described with reference to FIG. The above-described Example 1 and Example 2 are both batch-types in which the bag 14 or the container 54 is taken in and out for each treatment, but the sterilization apparatus of this example continuously applies a plurality of sterilization targets. It has a continuous configuration capable of performing processing. In the sterilization apparatus 70 of the present embodiment, an inlet 74A and an outlet 74B are formed on the front and rear surfaces of a processing chamber 72 that performs sterilization, and a conveyor 76 that moves in the direction of the arrow from the inlet 74A toward the outlet 74B is provided. Is provided. The processing chamber 72 is provided with the same microwave oscillator 64 as that of the second embodiment described above, and a container 54 sealed in advance so as to be easily discharged inside is placed on a conveyor 76 and placed in the processing chamber. Then, the sterilization target object 52 is continuously sterilized. The effect of the present embodiment is basically the same as that of the above-described second embodiment. However, according to the present embodiment, the conveyor 76 is used, so that the work efficiency can be improved by continuous processing. .

In addition, this invention is not limited to the Example mentioned above, A various change can be added in the range which does not deviate from the summary of this invention. For example, the following are also included.
(1) The shapes and sizes of the sterilizers 10, 50 and 70, the bag 14 and the container 54 in the above embodiment are merely examples, and can be arbitrarily changed according to the size and shape of the sterilization target 12 or 52. It is.
(2) In the above embodiment, one sterilization object 12 or 52 is placed in one bag 14 or container 54. However, a larger number of sterilization objects may be placed in one bag 14 or container 54 as necessary. You may make it enter.
(3) The hydrogen peroxide 18 is generally injected or applied directly into the bag 14 or the container 54. However, as shown in the first embodiment, the hydrogen peroxide 18 is used by impregnating the cloth 16 as necessary. May be. The desiccant 26 and the oxygen scavenger 28 may be packaged or stored in the bag 14 or the container 54 as necessary.

  (4) The processing procedure according to the above embodiment is also an example, and may be changed as appropriate so as to achieve the same effect. For example, in Example 1, the completely sealed bag 14 is placed in the processing chamber 20 of the sterilization apparatus 10, and the inside of the processing chamber 20 is depressurized, thereby utilizing the pressure difference inside and outside the bag 14. In the same manner as in the second embodiment, the pressure inside the bag 14 is reduced to a state where it can be easily discharged by an arbitrary exhausting means, and the pressure inside the processing chamber 20 is reduced by the vacuum pump 22. The microwave 32 may be irradiated in a state of atmospheric pressure without performing the above. Moreover, the procedure of impregnation, application, injection, etc. of hydrogen peroxide is also an example, and may be appropriately changed so as to achieve the same effect.

(5) In the above-described embodiment, the microwave discharge is performed. However, the same effect as the above-described embodiment can be obtained by the high-frequency discharge.
(6) The object to be sterilized in the above embodiment is also an example, and the sterilization method and apparatus of the present invention can be applied to various items that require sterilization.

  According to the present invention, the inside of the sealing means containing the object to be sterilized and a small amount of hydrogen peroxide (including hydrogen peroxide solution) is decompressed to a state where it can be easily discharged, and the process chamber in which the sealing means is placed cannot be discharged. In addition, after making it difficult to discharge, the processing chamber is irradiated with high frequency or microwave, and the gas containing hydrogen peroxide in the sealing means is turned into plasma to generate active oxygen. For this reason, since the space which sterilizes with active oxygen can be localized and limited, it can apply as a sterilization method and apparatus which can perform reliable sterilization processing and reduction of processing time and irradiation energy. In particular, since the sterilization process is performed after the object to be sterilized is sealed, the sterilized state can be maintained until the sealed container is opened, which is suitable for preventing secondary contamination during packaging.

It is a figure which shows an example of the sterilization process process by the sterilizer of Example 1 of this invention. It is a figure which shows the other Example of this invention, (A) is a perspective view which shows the structure of the sterilizer of Example 2, (B) is a perspective view which shows the structure of the sterilizer of Example 3. FIG.

Explanation of symbols

10: Sterilizer 12: Object to be sterilized 14: Bag 16: Cloth 18: Hydrogen peroxide 20: Processing chamber 22: Vacuum pump 24: Microwave oscillator 26: Desiccant 28: Deoxygenating agent 30: Irradiation port 32: Microwave 50: Sterilizer 52: Object to be sterilized 54: Container 56: Septum (check valve)
60: Processing chamber 62: Door 64: Microwave oscillator 66: Irradiation port 70: Sterilizer 72: Processing chamber 74A: Inlet 74B: Outlet 76: Conveyor

Claims (9)

A state in which the object to be sterilized and a small amount of hydrogen peroxide (including hydrogen peroxide solution) are packaged or stored in a sealing means that can transmit high frequency or microwave, and the inside of the sealing means placed in the processing chamber is easily discharged. With the pressure reduced to
The treatment chamber is made incapable of being discharged or difficult to discharge, and the processing chamber is irradiated with the high frequency or microwave, and a gas containing hydrogen peroxide in the sealing means is turned into plasma to generate active oxygen, A sterilization method comprising sterilizing the object to be sterilized with oxygen. A processing chamber for performing sterilization on a sterilized object packaged or stored in a bag-like sealing means having high-frequency or microwave permeability with a small amount of hydrogen peroxide (including hydrogen peroxide solution);
Exhaust means for evacuating the processing chamber to a state where discharge is impossible or difficult to discharge and reducing the pressure, thereby expanding the sealing means in the processing chamber by a pressure difference between the inside and the outside and reducing the inside of the sealing means to a state where discharge is easily performed ,
Irradiation means for irradiating the processing chamber with a high frequency or microwave, generating a plasma containing a gas containing hydrogen peroxide in the sealing means, and generating active oxygen for sterilizing the object to be sterilized,
A sterilization apparatus comprising:   3. The sterilization apparatus according to claim 2, wherein the sealing means is a plastic bag or a composite bag made of plastic and another material. For sterilized objects packaged or stored with a small amount of hydrogen peroxide (including hydrogen peroxide solution) in a sealing means that has high-frequency or microwave permeability and is decompressed to a state where the inside is easily discharged. Processing chamber for sterilization,
Irradiation means for generating active oxygen for sterilizing the object to be sterilized by irradiating the processing chamber in an atmospheric pressure state with a high frequency or microwave, converting the gas containing hydrogen peroxide in the sealing means into plasma,
A sterilization apparatus comprising:   5. The sterilizer according to claim 4, wherein the sealing means is any one of a plastic bag, a composite bag made of plastic and other materials, or a container made of plastic or glass.   The said sealing means has another valve | bulb means which enables exhaust_gas | exhaustion in this sealing means, or the valve | bulb or partition which can inject | pour hydrogen peroxide in the inside of a vacuum or pressure reduction state, It is characterized by the above-mentioned. The sterilizer according to any one of 5.   The sterilizer according to any one of claims 2 to 6, wherein the pressure in the sealing means is 0.1 to 10 Torr.   The sealing means packs at least one of a desiccant that absorbs water generated by decomposition of the hydrogen peroxide and an oxygen absorber that absorbs oxygen generated by the decomposition together with the sterilization object and hydrogen peroxide. The sterilizer according to any one of claims 2 to 7, wherein the sterilizer is stored.   A sterilization method using the sterilizer according to claim 2 to sterilize an object to be sterilized in the sealing means.

Images