Sterilization method and sterilization device

Abstract

The sterilization method comprises: a pre-decompression step (S200), in which after a sterilization object packaged with a packaging material is placed in a chamber (11), the interior of the chamber (11) is decompressed relative to atmospheric pressure, and the packaging material uses a material that absorbs ozone gas and hydrogen peroxide; an ozone adsorption step (S300), in which ozone gas is injected into the interior of the chamber (11) under the decompression of the pre-decompression step (S200), and the ozone gas is adsorbed on the packaging material; and a sterilization step (S500), in which, after the ozone adsorption step (S300), the sterilization object is sterilized using ozone gas and hydrogen peroxide.

Description

Technical Field

[0001] The invention relates to a sterilization method and a sterilization device. Background Art

[0002] Medical instruments used in hospitals for surgery and treatment are reused and then sterilized after being thoroughly cleaned to remove deposits such as blood and protein.

[0003] As a method for performing such a sterilization treatment, there is a sterilization method in which hydrogen peroxide is used as the main gas as the sterilization gas and other gases are further used in order to further improve the sterilization efficiency. Patent document 1 discloses a sterilization method and apparatus including a series of steps of injecting steam of a hydrogen peroxide aqueous solution to sterilize and maintain after decompressing a chamber containing a sterilization object, and then injecting ozone gas to sterilize and maintain.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent No. 5480975 Summary of the invention

[0007] When sterilizing an object to be sterilized using a sterilization device such as that disclosed in Patent Document 1, the object to be sterilized is contained in a chamber of the sterilization device after being pre-packed with a packaging material such as a sterilization bag in order to suppress re-contamination after sterilization. However, in the actual sterilization process of the object to be sterilized packed with the packaging material, there are cases where components of the sterilization gas are adsorbed on the packaging material. Such adsorbed matter may also prevent the sterilization gas that is continuously supplied from reaching the object to be sterilized.

[0008] Therefore, an object of the present invention is to provide a sterilization method and a sterilization apparatus capable of improving the sterilization efficiency as a whole of the sterilization process.

[0009] The sterilization method of the first scheme of the present invention includes: a pre-decompression step, in which the interior of the chamber is decompressed relative to the atmospheric pressure after the sterilization object packaged by the packaging material is placed in the chamber, and the packaging material uses a material that absorbs ozone gas and hydrogen peroxide; an ozone adsorption step, in which ozone gas is injected into the interior of the chamber under the reduced pressure of the pre-decompression step and the ozone gas is adsorbed on the packaging material; and a sterilization step, in which the sterilization object is sterilized using ozone gas and hydrogen peroxide after the ozone adsorption step.

[0010] In addition, a second embodiment of the present invention provides a sterilization device for sterilizing an object to be sterilized, comprising: a chamber for accommodating an object to be sterilized packaged with a packaging material made of a material that absorbs ozone gas and hydrogen peroxide; an evaporator connected to the chamber and filled with an aqueous solution of hydrogen peroxide, water from which pyrogens have been removed or inactivated, water from which bacteria or microorganisms have been removed or inactivated, pure water, water from which scale has been removed, water that has been topped up, or a solution containing volatile components; an ozone generator connected to the chamber and generating ozone gas; and a control unit for controlling the injection of steam generated in the evaporator or ozone gas generated in the ozone generator into the interior of the chamber, the control unit depressurizing the interior of the chamber, injecting ozone gas into the interior of the chamber under the depressurized condition, and sterilizing the object to be sterilized using the ozone gas and hydrogen peroxide. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram showing the structure of a sterilization apparatus according to one embodiment.

[0012] Figure 2 This is a flowchart showing the flow of a sterilization method according to one embodiment.

[0013] Figure 3 Graph showing pressure changes inside a chamber according to one embodiment.

[0014] Figure 4 This is a table showing each processing mode performed by the sterilization apparatus according to one embodiment.

[0015] Figure 5 This is a flowchart showing the flow of a sterilization process according to one embodiment. DETAILED DESCRIPTION

[0016] Hereinafter, one embodiment of the present invention will be described in detail with reference to the accompanying drawings. Herein, the dimensions, materials, and specific numerical values ​​shown in one embodiment are merely illustrative, and do not limit the present invention unless otherwise specified. In addition, for elements having substantially the same function and structure, repeated descriptions are omitted by marking the same reference numerals, and elements that are not directly related to the present invention are omitted from illustration.

[0017] Figure 1 1 is a schematic diagram showing the structure of the sterilization device 100 of this embodiment. The sterilization device 100 sterilizes the sterilization object using a sterilization gas. The substance constituting the sterilization gas used in this embodiment is mainly hydrogen peroxide (H2O 2 ) and ozone (O 3 ).

[0018] As the sterilization object, medical devices that are used in hospitals for surgery and treatment and come into contact with the vascular system and sterile tissues are conceivable. Such medical devices include heat-resistant steel products such as forceps, tweezers, scissors, etc., stainless steel rigid endoscopes for laparoscopic surgery, or soft endoscopes for bronchial and urinary organ surgery, as well as non-heat-resistant resin products such as power cables as their accessories. In addition, in order to suppress re-contamination after sterilization, the sterilization object is contained in the chamber 11 of the sterilization device 100 in a state of being pre-packaged with packaging materials. The packaging material is, for example, a non-woven fabric, and because the mesh is fine, although the sterilizing gas can pass through, it is difficult for bacteria to pass through. The non-woven fabric can also be mainly made of resins such as polyethylene. Such packaging materials are sometimes also called sterilization bags or sterilization rolls.

[0019] The sterilization apparatus 100 includes a chamber unit 10 , a hydrogen peroxide supply unit 20 , an ozone supply unit 30 , an exhaust unit 40 , an air introduction unit 50 , and a control unit 60 .

[0020] The chamber unit 10 includes a chamber 11 for accommodating objects to be sterilized and its peripheral structure. The chamber unit 10 includes the chamber 11 including a door 12 , a first heater 13 , and a first pressure gauge 14 .

[0021] The chamber 11 is a container that can accommodate the sterilization object arranged inside. The chamber 11 is also called a sterilization warehouse. The chamber 11 is made of stainless steel or aluminum alloy and has a structure that can withstand vacuum and reduced pressure. In the following, as an example, the internal volume of the chamber 11 is set to 100L. The door 12 can be opened and closed relative to the chamber 11. When the door 12 is closed and the interior of the chamber 11 is depressurized, the chamber 11 is sealed to suppress vacuum leakage and leakage of sterilization gas.

[0022] The first heater 13 is provided around the chamber 11 together with the heat insulating material, and keeps the temperature inside the chamber 11 constant during the sterilization process. The temperature of the chamber 11 is measured using a thermometer (not shown) provided in the chamber 11 .

[0023] The first pressure gauge 14 is a vacuum gauge that is provided in the chamber 11 and measures the pressure inside the chamber 11 .

[0024] The hydrogen peroxide supply unit 20 supplies hydrogen peroxide vapor to the chamber 11 during the sterilization process. In the present embodiment, the hydrogen peroxide supply unit 20 can separately supply vapors generated from two aqueous hydrogen peroxide solutions. Hereinafter, one aqueous hydrogen peroxide solution is referred to as the "first aqueous solution" and the other aqueous hydrogen peroxide solution is referred to as the "second aqueous solution". The concentration of hydrogen peroxide contained in the first aqueous solution or the second aqueous solution, or the total amount of hydrogen peroxide contained in the first aqueous solution or the second aqueous solution, will be described in detail below, but will be specified based on the presence or absence of a lumen of the sterilization object and the material of the sterilization object. The hydrogen peroxide supply unit 20 includes a bottle 21, an extraction pipe 22, a tubular pump 23, a storage unit 24, an evaporator 26, and a second heater 29.

[0025] The bottle 21 contains an aqueous solution of hydrogen peroxide. For a so-called disposable bottle, the bottle 21 is also called a cartridge. In this embodiment, two aqueous solutions of hydrogen peroxide are used, so there is a first bottle 21a containing a first aqueous solution and a second bottle 21b containing a second aqueous solution.

[0026] The extraction pipe 22 extracts the aqueous solution of hydrogen peroxide from the bottle 21 and supplies the extracted aqueous solution to the storage unit 24. In this embodiment, there are a first extraction pipe 22a for extracting the first aqueous solution from the first bottle 21a and a second extraction pipe 22b for extracting the second aqueous solution from the second bottle 21b.

[0027] The tube pump 23 is provided in the middle of the extraction pipe 22, and sucks out an appropriate amount of the aqueous solution of hydrogen peroxide from the bottle 21 gradually. In the present embodiment, there is a first tube pump 23a provided in the middle of the first extraction pipe 22a and a second tube pump 23b provided in the middle of the second extraction pipe 22b. In addition, although not shown, an optical liquid level sensor, for example, may be provided in the extraction pipe 22. The tube pump 23 draws the aqueous solution of hydrogen peroxide until the liquid level sensor reacts, and after the liquid level sensor reacts, it temporarily stops drawing and rotates at a predetermined rotation speed, thereby supplying a predetermined amount to the storage portion 24.

[0028] The storage unit 24 is connected to the extraction pipe 22, and temporarily stores a predetermined amount of the aqueous solution of hydrogen peroxide drawn from the bottle 21 before sending it to the evaporator 26. As the storage unit 24, a translucent fluorine resin tube or the like, which allows the amount of liquid inside to be visible, can be used. For the tube pump 23, driving under atmospheric pressure can stably supply a fixed amount, so the storage unit 24 can also be introduced into the atmosphere through the first filter 25 to become atmospheric pressure. The first filter 25 is, for example, a HEPA filter.

[0029] The evaporator 26 communicates with the reservoir 24 via the first supply pipe 27, and evaporates the aqueous solution of hydrogen peroxide introduced from the reservoir 24. The evaporator 26 is made of, for example, stainless steel to withstand corrosion by hydrogen peroxide, and is depressurized simultaneously with the chamber 11, so it has a structure that can withstand vacuum and decompression.

[0030] The first solenoid valve 70 is provided in the first supply piping 27. When the first solenoid valve 70 is opened, the aqueous solution of hydrogen peroxide in the storage section 24 is sucked toward the decompressed evaporator 26. At this time, the storage section 24 is introduced into the atmosphere through the first filter 25 and becomes at atmospheric pressure, so the atmosphere is also sucked in together with the aqueous solution of hydrogen peroxide. As a result, the aqueous solution of hydrogen peroxide remaining in the storage section 24 and the first supply piping 27 is also sucked into the evaporator 26, so that the vapor of hydrogen peroxide is quantitatively and stably sent into the interior of the chamber 11.

[0031] In addition, the evaporator 26 is connected to the chamber 11 via a plurality of injection pipes 28. In the present embodiment, there are a first injection pipe 28a and a second injection pipe 28b which are arranged diagonally at the top. A second electromagnetic valve 71 is provided in the first injection pipe 28a, and a third electromagnetic valve 72 is provided in the second injection pipe 28b. When the aqueous solution of hydrogen peroxide evaporates in the evaporator 26 and the pressure inside the evaporator 26 increases, the second electromagnetic valve 71 or the third electromagnetic valve 72 is opened for a constant time, so that the vapor of the aqueous solution of hydrogen peroxide is injected into the chamber 11. The injection pipe 28 is provided in plurality in this way, so that the diffusion of the vapor inside the chamber 11 is more uniform. In addition, a pressure sensor 39 may be provided in the evaporator 26, and the pressure sensor 39 is used to determine whether a predetermined amount of vapor is supplied from the storage unit 24 according to whether it is within a predetermined pressure range after the injection of the vapor.

[0032] The second heater 29 is provided around the evaporator 26, and keeps the temperature inside the evaporator 26 constant. The inside of the evaporator 26 is kept constant at a predetermined temperature between 65 and 120 degrees Celsius, for example.

[0033] The ozone supply unit 30 supplies ozone gas to the chamber 11 during sterilization. In the present embodiment, ozone gas is generated in the ozone supply unit 30. The ozone supply unit 30 includes an oxygen generator 31, an ozone generator 32, an ozone concentration meter 33, a buffer tank 34, and a second pressure gauge 35.

[0034] The oxygen generator 31 generates oxygen (O 2). As a method of the oxygen generator 31, for example, a PSA (Pressure Swing Adsorption) method can be adopted in which nitrogen in the air is adsorbed on an adsorbent such as zeolite to generate a high concentration of oxygen. Specifically, the oxygen generator 31 may be a PSA device having a discharge pressure of about 0.03 to 0.08 MPa according to a gauge pressure and a flow rate of about 1 to 4 L / min. A fourth solenoid valve 73 is provided in the piping connecting the oxygen generator 31 and the ozone generator 32. The supply amount of oxygen to the ozone generator 32 is adjusted by appropriately controlling the opening and closing of the fourth solenoid valve 73.

[0035] The ozone generator 32 generates ozone gas using the oxygen generated by the oxygen generating device 31. As a method of the ozone generator 32, for example, a silent discharge method can be adopted in which a high-frequency high voltage is applied to oxygen to discharge and decompose it to generate ozone. In the ozone supply unit 30, as an example, there are two ozone generators 32. For example, the generation capacity of the ozone generator 32 is expressed as (2g / hr×2 units)=4g / hr. In this case, the ozone generator 32, for example, receives a supply of 1L / min of oxygen while working for 1.5 minutes, thereby being able to generate (4g×1.5 minutes / 60 minutes)=0.1g of ozone. The ozone generator 32 is connected to the buffer tank 34 via the second supply pipe 36.

[0036] The ozone concentration meter 33 measures the concentration of the ozone gas generated by the ozone generator 32 in the second supply pipe 36. For example, when ozone gas is circulated into the second supply pipe 36 at a flow rate of 1 L / min for 1.5 minutes, the measured value of the ozone concentration meter 33 is 70 g / m 3 . In this case, the amount of ozone generated is equivalent to (1L / min×1.5 minutes×70g / 1000L)=0.105g. Then, 0.105g of ozone gas is injected into the interior of the chamber 11 with a volume of 100L, and air is further introduced to achieve atmospheric pressure. The ozone concentration in the chamber 11 at this time is equivalent to a volume concentration of (0.105g / 48g×22.4L / 100L×1,000,000)=490ppm based on the molecular weight of ozone 48 and the standard gas 22.4L.

[0037] A fifth electromagnetic valve 74 is provided between the ozone concentration meter 33 and the buffer tank 34 of the second supply pipe 36. In addition, the ozone concentration meter 33 and the fifth electromagnetic valve 74 of the second supply pipe 36 may be connected to the exhaust unit 40 via the pipe system X including the sixth electromagnetic valve 75. That is, when the fifth electromagnetic valve 74 is closed and the sixth electromagnetic valve 75 is opened, the ozone gas flowing from the ozone generator 32 is supplied to the exhaust unit 40 side.

[0038] The buffer tank 34 temporarily stores the ozone gas generated in the ozone generator 32 before sending it to the evaporator 26. The buffer tank 34 is made of, for example, stainless steel to withstand corrosion by hydrogen peroxide and has a structure that can withstand reduced pressure. Hereinafter, as an example, the volume of the buffer tank 34 is set to 2L. The buffer tank 34 is connected to the evaporator 26 via the third supply pipe 37. The third supply pipe 37 is provided with a seventh solenoid valve 76. When ozone gas is injected into the buffer tank 34 when the seventh solenoid valve 76 is closed, the pressure inside the buffer tank 34 temporarily increases.

[0039] The second pressure gauge 35 is a vacuum gauge provided in the buffer tank 34 to measure the pressure inside the buffer tank 34. The control unit 61 monitors the pressure inside the buffer tank 34 using the second pressure gauge 35, thereby being able to confirm whether ozone reaching a predetermined pressure has been injected into the buffer tank 34, or whether ozone leakage or blockage has occurred in the second supply pipe 36 or the like.

[0040] In the present embodiment, the ozone gas supplied from the buffer tank 34 is not directly injected into the chamber 11 but is injected into the chamber 11 via the evaporator 26. That is, the inlet of the sterilizing gas into the chamber 11 is common to hydrogen peroxide and ozone gas.

[0041] It should be noted that, as another embodiment, the ozone gas may be directly injected into the chamber 11 from the buffer tank 34 without passing through the evaporator 26. In this case, there is an advantage that the ozone gas is directly injected into the chamber 11 without passing through the evaporator 26, and accordingly the diffusion of the ozone gas in the chamber 11 becomes faster. In addition, in this case, there is an advantage that if the second electromagnetic valve 71 and the third electromagnetic valve 72 between the evaporator 26 and the chamber 11 are closed, the ozone concentration in the chamber 11 increases.

[0042] The exhaust unit 40 exhausts the ambient gas inside the chamber 11, thereby reducing the pressure inside the chamber 11, or exhausts the gas existing inside the chamber 11 to the outside. Specifically, in order to improve the sterilization effect during the sterilization process, the exhaust unit 40 extracts excess gas from the chamber 11 and the sterilization object itself before the sterilization process, and reduces the pressure inside the chamber 11 to a medium vacuum standard of, for example, below 100 Pa. In addition, the exhaust unit 40 exhausts the sterilization gas remaining in the chamber 11 and the sterilization object after the sterilization process. The exhaust unit 40 includes a vacuum pump 41, a catalyst tank, and a heater.

[0043] As the vacuum pump 41, for example, a dry pump such as a vortex pump or an oil rotary pump such as a rotary pump that can cope with a vacuum can be used. In the present embodiment, the vacuum pump 41 is an oil rotary pump. The vacuum pump 41 is connected to the chamber 11 via the exhaust pipe 38. The exhaust pipe 38 is provided with an eighth electromagnetic valve 77. For example, when reducing pressure, after the pressure inside the chamber 11 reaches a predetermined value, the control unit 61 closes the eighth electromagnetic valve 77 and stops the operation of the vacuum pump 41.

[0044] The catalyst tank is made of, for example, stainless steel and contains a granular or honeycomb catalyst. The catalyst has, for example, manganese dioxide as a main component and decomposes hydrogen peroxide and ozone. In the present embodiment, the catalyst tank is disposed at two locations, the upstream side and the downstream side of the vacuum pump 41, in consideration of decomposing the gas that may corrode the vacuum pump and appropriately maintaining the exhaust speed. The first catalyst tank 42 is a catalyst tank disposed at the upstream side of the vacuum pump 41. The second catalyst tank 43 is a catalyst tank disposed at the downstream side of the vacuum pump 41.

[0045] Here, as described above, the ozone supply unit 30 can supply ozone gas to the exhaust unit 40 via the pipe system X by appropriately controlling the ozone generator 32 , the fifth electromagnetic valve 74 , and the sixth electromagnetic valve 75 .

[0046] The heater keeps the catalyst tank at, for example, 60 to 90° C. The third heater 44 keeps the first catalyst tank 42 warm. The fourth heater 45 keeps the second catalyst tank 43 warm.

[0047] The air introduction unit 50 introduces air into the chamber 11. The air introduction unit 50 includes a second filter 51 and a plurality of introduction ports.

[0048] When the air is introduced, the second filter 51 prevents dust in the air from entering the chamber 11. As the second filter 51, for example, a HEPA filter made of fine-meshed nonwoven fabric can be used.

[0049] The inlet port introduces the atmosphere introduced through the second filter 51 into the interior of the chamber 11. In order to make the gas concentration inside the chamber 11 uniform according to the introduction of the atmosphere, the inlet port is preferably provided at multiple different positions of the chamber 11. In the present embodiment, as an example, there are two inlets, a first inlet port 52 and a second inlet port 53, which are provided at diagonals to each other at the top. A ninth solenoid valve 78 is provided at the first inlet port 52. A tenth solenoid valve 79 is provided at the second inlet port 53. The control unit 61 controls the opening and closing of the ninth solenoid valve 78 or the tenth solenoid valve 79 individually, so that the atmosphere can be introduced into the interior of the chamber 11 from different positions at an appropriate time.

[0050] It should be noted that the introduction port is not limited to being directly provided in the chamber 11. As another embodiment, the introduction port may be connected to the chamber 11, for example, via the evaporator 26. Alternatively, the introduction port may be connected to the chamber 11, for example, via the buffer tank 34. Furthermore, the introduction port may be connected to the chamber 11, for example, via both the evaporator 26 and the buffer tank 34.

[0051] The control unit 60 controls the driving of the power system elements in each unit constituting the sterilization device 100 based on various action instructions. The control unit 60 includes a control unit 61 and a touch panel 62. The control unit 61 is electrically connected to various power system elements, measurement system elements, etc. The control unit 61 controls the actions of various power system elements based on, for example, instructions input via the touch panel 62, a control sequence maintained in advance, or detection signals from various sensors. The touch panel 62 is electrically connected to the control unit 61 and is used for the operator to input information, instructions, or visually confirm information prompted from the device side.

[0052] Next, the flow of the sterilization method according to the present embodiment using the sterilization apparatus 100 will be described.

[0053] Figure 2 This is a flowchart showing the flow of the sterilization method according to the present embodiment. Figure 3 It is a graph showing the change in the pressure inside the chamber 11 with respect to the elapsed time along the flow of the sterilization method according to the present embodiment.

[0054] The sterilization method of this embodiment includes a treatment mode selection step S100, a pre-decompression step S200, an ozone adsorption step S300, a sterilization decompression step S400, a sterilization step S500, and a ventilation step S700.

[0055] First, before starting the processing mode selection step S100, a hospital nurse or other operator places the sterilization object packaged with the packaging material in the chamber 11, closes the door 12, and seals the interior of the chamber 11. It should be noted that at this point in time, the sterilization device 100 is already powered on, and the warm-up operation is completed.

[0056] In the sterilization process of this embodiment, the operator can select a processing mode according to the type of the sterilization object. The type of the sterilization object is classified, for example, according to the shape, material, etc. of the sterilization object. In particular, the shape of the sterilization object can also be classified according to the presence or absence of a lumen. The processing mode selection process S100 is a process in which the operator inputs the selected processing mode to the sterilization device 100.

[0057] Figure 4: is a table showing various processing modes that can be implemented by the sterilization device 100. As processing modes, for example, the following three modes can be set. The short mode is suitable for the case where the sterilization object is a medical device without a lumen. The medical device in this case is, for example, a steel product such as forceps, etc., which is mainly subjected to surface sterilization. The standard mode is suitable for the case where the sterilization object is a medical device made of resin with a lumen. The long mode is suitable for the case where the sterilization object is a medical device made of stainless steel with a lumen. The medical device in this case is, for example, a thin tube with an inner diameter of approximately 1 mm, i.e., a rigid endoscope.

[0058] For each treatment mode, for example, the treatment time in the subsequent steps, the injection amount of the aqueous solution of hydrogen peroxide, or the number of exposure times are different. Figure 4 The column of the injection amount of the aqueous solution of hydrogen peroxide in the table shows the possible range of the value of each pulse, wherein one pulse corresponds to one sterilization step S500 described below. In particular, the generation number related to the injection amount of the first aqueous solution is shown in the upper part, and the generation number related to the injection amount of the second aqueous solution is shown in the lower part.

[0059] Next, the pre-decompression step S200 is a step of decompressing the interior of the chamber 11 relative to the atmospheric pressure as a pre-step of the ozone adsorption step S300 to be performed later. Figure 3 In the embodiment, the period during which the pre-depressurization step S200 is performed is referred to as H11. In the pre-depressurization step S200, the interior of the chamber 11 is depressurized to 100 Pa, for example.

[0060] The ozone adsorption step S300 is a step of injecting ozone gas into the interior of the chamber 11 under the reduced pressure of the previous decompression step S200, and adsorbing the ozone gas onto the packaging material for packaging the sterilization object. In the present embodiment, thereafter, an ozone injection step S505 is performed in addition to the ozone adsorption step S300. If the ozone adsorption step S300 is not performed, there is a case where the ozone gas injected into the interior of the chamber 11 in the ozone injection step S505 is adsorbed onto the packaging material for packaging the sterilization object. Ozone as such an adsorbent may also prevent the ozone gas that continues to be supplied from reaching the sterilization object. Therefore, in the present embodiment, before the ozone injection step S505 is performed, the ozone gas is adsorbed onto the packaging material in the ozone adsorption step S300, so that the packaging material is saturated or close to saturated. By making the packaging material saturated or close to saturated in advance, when ozone gas is injected into the chamber 11 in the ozone injection step S505, the ozone gas is less likely to be adsorbed by the packaging material, resulting in the ozone gas easily reaching the sterilization object. It should be noted that the ozone gas injected in the ozone adsorption step S300 is not only adsorbed by the packaging material, but also reaches the sterilization object, thereby contributing to sterilization.

[0061] Here, it is also considered that if the concentration of ozone gas in the gas supplied to the inside of the chamber 11 in the ozone adsorption step S300 is increased, the subsequent ozone injection step S505 is unnecessary. On the contrary, it is also considered that if the concentration of ozone gas in the gas supplied to the inside of the chamber 11 in the ozone injection step S505 is increased, the ozone adsorption step S300 is unnecessary. However, if the concentration of ozone gas is increased in this way, it is more likely that the sterilization object will be affected by unexpected factors such as deformation due to the material of the sterilization object. In contrast, as in the present embodiment, in a series of steps included in the sterilization method, the step of injecting ozone gas into the inside of the chamber 11 is dispersed into a plurality of steps, thereby further mitigating the influence of ozone gas on the shape, composition, etc. of the sterilization object. If such mitigation of the influence of ozone gas is also considered, as a regulation related to the concentration of ozone gas, about 1% of ozone gas is contained in the gas supplied to the inside of the chamber 11 in the ozone adsorption step S300. If ozone gas is generated in the ozone supply unit 30 as in the present embodiment, then at this time, about 99% of the gas supplied to the interior of the chamber 11 other than the ozone gas is oxygen. For example, if the concentration of the ozone gas is set higher, high functionality may be required for components such as the ozone generator 32 that generates the ozone gas. Therefore, it is preferred to set the concentration of the ozone gas to about 1% in terms of the ease of ozone generation in the ozone generator 32. In addition, if the concentration of the ozone gas is set to about 1%, the concentration of the ozone gas after being injected into the interior of the chamber 11 can be made less than 500 ppm, which is preferred in terms of suppressing unexpected effects on the sterilization object.

[0062] exist Figure 3 In the embodiment, the timing of starting the ozone adsorption step S300 is recorded as T11. In addition, after the ozone gas is injected into the chamber 11 in the ozone adsorption step S300, Figure 3 As shown, the internal state of the chamber 11 may be maintained during the period H12. For example, when the processing mode is the short mode, the concentration of the ozone gas in the ozone adsorption process S300 may be approximately 400 ppm, which corresponds to a holding time of approximately 3 minutes during the period H12. In this case, the exposure condition of the ozone gas is approximately 400 (ppm) × 3 (minutes) = 1200 (ppm·minutes). It should be noted that the control performed by the control unit 61 when injecting the ozone gas is the same as the control in the ozone injection process S505 described later. In addition, a preparation process identical to the ozone preparation process S504 described later may be provided before the ozone adsorption process S300.

[0063] As exemplified above, the content of oxygen in the gas supplied to the interior of the chamber 11 in the ozone adsorption step S300 is much higher than the content of the ozone gas. On the other hand, in the present embodiment, thereafter, as the first steam injection step S502, the steam of the first aqueous solution of hydrogen peroxide is injected into the interior of the chamber 11. In a state where a large amount of oxygen remains in the interior of the chamber 11, even if the steam of the first aqueous solution is injected into the interior of the chamber 11 in the first steam injection step S502, it is difficult for hydrogen peroxide to reach the surface of the sterilization object. The sterilization decompression step S400 is a step for removing the oxygen remaining in the interior of the chamber 11 before the first steam injection step S502 in consideration of such a situation. In addition, by decompressing the interior of the chamber 11 in the sterilization decompression step S400, the accessibility of hydrogen peroxide to the sterilization object can be improved.

[0064] In the sterilization and decompression step S400, the control unit 61 starts the vacuum pump 41 and opens the eighth electromagnetic valve 77, thereby Figure 3 During the period H13 shown, the interior of the chamber 11 is depressurized. At this time, the control unit 61 opens the second electromagnetic valve 71, the third electromagnetic valve 72, and the seventh electromagnetic valve 76, thereby depressurizing the interior of the chamber 11 and the interiors of the evaporator 26 and the buffer tank 34. Figure 4 The processing time in the table is calculated from the time point when the decompression starts at this time.

[0065] The target pressure of the sterilization decompression step S400 is a pressure sufficient to remove oxygen and ensure that the steam of the first aqueous solution of hydrogen peroxide reaches the sterilization object in the subsequent first steam injection step S502. For example, the target pressure is set to 50 Pa or less, more specifically, preferably 25 to 35 Pa.

[0066] After reaching the target pressure, the control unit 61 closes the second electromagnetic valve 71, the third electromagnetic valve 72, the seventh electromagnetic valve 76 and the eighth electromagnetic valve 77, and stops the vacuum pump 41. The control unit 61 moves to the sterilization step S500 after the sterilization and decompression step S400. It should be noted that, after the sterilization and decompression step S400, the control unit 61 may also Figure 3 As shown, the internal state of the chamber 11 is maintained during the period H14.

[0067] Here, when the treatment mode is the long mode, the sterilization object is, for example, a stainless steel capillary tube. Therefore, when the long mode is selected, the temperature of the sterilization object may be raised in advance, and the pressure reached may be maintained at a constant time of, for example, about 2 minutes, so as to minimize the influence of condensation in the tube lumen.

[0068] Figure 5: is a flowchart showing the flow of the sterilization step S500. The sterilization step S500 is a step that mainly contributes to the sterilization of the sterilization object. The sterilization step S500 includes a first steam preparation step S501, a first steam injection step S502, and a first state maintaining step S503.

[0069] The first steam preparation step S501 is a step for generating steam of the first aqueous solution to be injected in the next first steam injection step S502. First, the control unit 61 rotates the first tube pump 23a to draw the first aqueous solution from the first bottle 21a, and then injects a predetermined amount of aliquots into the storage unit 24. Here, the predetermined amount is the total amount injected per pulse, such as Figure 3 As shown, it is different according to the treatment mode. For example, when the treatment mode is the short mode, the concentration of hydrogen peroxide contained in the first aqueous solution is a predetermined concentration (x1) between 30% and 60%, and the predetermined amount is a predetermined amount (y1) between 1 and 4 ml. For example, when the predetermined amount is divided into two parts, the amount of the equal part of the predetermined amount is a predetermined amount (y1÷2) between 0.5 and 2 ml, which is half of y1. Next, the control unit 61 opens the first electromagnetic valve 70 for a constant time of 5 seconds, for example. Since the inside of the evaporator 26 has been depressurized, the first aqueous solution is instantly sucked into the evaporator 26. At this time, the storage unit 24 is connected to the atmosphere via the first filter 25, so the atmosphere enters the storage unit 24, and the first aqueous solution remaining in the storage unit 24, the first supply pipe 27, etc. is also sent to the evaporator 26. Next, the control unit 61 closes the first electromagnetic valve 70, for example, and evaporates the first aqueous solution in the evaporator 26 for a constant time of 5 seconds. At this time, the evaporator 26 is constantly heated at a predetermined temperature between 65 and 120°C, for example. For example, if the amount of the first aqueous solution is adjusted so as to evaporate almost completely and then introduced into the evaporator 26 having a predetermined volume of 0.5 to 2 L and a pressure of 50 Pa, the pressure is considered to rise to the saturated vapor pressure. After the first steam preparation step S501, the control unit 61 moves to the first steam injection step S502.

[0070] The first vapor injection step S502 is a step of injecting the vapor of the first aqueous solution generated in the evaporator 26 into the chamber 11. Figure 3In the embodiment, the timing of starting the first steam injection step S502 is recorded as T12. First, the control unit 61 opens the second electromagnetic valve 71 and the third electromagnetic valve 72 for a constant time of 10 seconds, for example. As a result, the steam of the first aqueous solution is violently injected into the interior of the chamber 11 in accordance with the pressure difference. At this time, especially when the sterilization object has a lumen, the greater the pressure difference, the easier it is for the steam to penetrate into the interior of the lumen. In addition, as described above, the steam is easy to be uniform inside the chamber 11. Next, the control unit 61 closes the second electromagnetic valve 71 and the third electromagnetic valve 72. Then, the control unit 61 repeatedly injects the steam of the first aqueous solution in the same steps according to the treatment mode. For example, when the treatment mode is the short mode, the steam of the first aqueous solution of a predetermined concentration (x1) between 30% and 60% × a predetermined amount (y1) between 1 and 4 ml is injected into the evaporator 26 for each pulse. At this time, if a large amount of the first aqueous solution is injected at one time, the saturated vapor pressure may also be reached inside the evaporator 26, so that the first aqueous solution cannot be fully evaporated and remains. Therefore, the control unit 61 may, for example, evaporate the first aqueous solution twice and evaporate half of the first aqueous solution each time, and inject the first aqueous solution into the chamber 11 each time. Here, the control unit 61 may further inject the vapor of the first aqueous solution multiple times. After the first vapor injection step S502, the control unit 61 moves to the first state maintaining step S503.

[0071] The first state maintaining step S503 is a step of sterilizing the sterilization object by maintaining the steam of the first aqueous solution in the chamber 11 for a certain period of time. Figure 3 In the embodiment, the holding time is recorded as H15. The holding time at this time is different for each processing mode. The holding time in the short mode is, for example, 3 minutes. The holding time in the standard mode is, for example, 4 minutes. The holding time in the long mode is, for example, 6 minutes. That is, the holding time gradually increases in the order of the short mode, the standard mode, and the long mode.

[0072] Next, the sterilization step S500 includes an ozone preparation step S504 and an ozone injection step S505.

[0073] The ozone preparation process S504 is a process for generating ozone gas to be injected in the subsequent ozone injection process S505. The ozone preparation process S504 does not need to wait for the first state holding process S503 to be completed, and it is sufficient to be executed before the ozone injection process S505 to prepare the ozone gas. First, the control unit 61 opens the fourth electromagnetic valve 73 to supply high-concentration oxygen to the ozone generator 32. Here, it is also possible that the control unit 61 closes the fifth electromagnetic valve 74 and opens the sixth electromagnetic valve 75 within a period of tens of seconds after driving the ozone generator 32, so that the ozone gas flows to the piping system of the first catalyst tank 42 instead of being sent to the buffer tank 34 before the concentrations of oxygen and ozone stabilize. Next, the control unit 61 closes the sixth electromagnetic valve 75 and opens the fifth electromagnetic valve 74, thereby filling the buffer tank 34 with ozone gas at a constant flow rate, constant concentration, and constant time. Next, after the filling of the buffer tank 34 with the ozone gas is completed, the control unit 61 closes the fifth electromagnetic valve 74 to stop the driving of the ozone generator 32 .

[0074] The ozone injection step S505 is a step of injecting the ozone gas generated in the ozone preparation step S504 into the chamber 11. Figure 3 , the timing of starting the ozone injection step S505 is recorded as T13. The ozone injection step S505 is executed after the first state maintaining step S503 is completed. The control unit 61 opens the seventh solenoid valve 76, the second solenoid valve 71 and the third solenoid valve 72 for a constant time of, for example, 5 seconds, and injects ozone gas into the chamber 11. Here, the pressure inside the buffer tank 34 is, for example, a pressure between 0.03 and 0.08 MPa at a maximum gauge pressure, or a prescribed pressure between 0.13 and 0.18 MPa at an absolute pressure. Therefore, it is conceivable that the injection of ozone gas into the interior of the chamber 11 under reduced pressure at an absolute pressure of less than 3000 Pa is completed in a few seconds due to the pressure difference.

[0075] In this way, the sterilizing device 100 can inject ozone gas into the interior of the chamber 11 when the pressure of the ozone gas in the buffer box 34 increases by using the buffer box 34. By injecting the ozone gas in this way, the diffusion of the ozone gas inside the chamber 11 can be made more uniform. In addition, the ozone can be easily introduced into the interior of the tube of the sterilization object having a lumen. In other words, the amount of ozone used can be further reduced while maintaining the sterilization efficiency.

[0076] In addition, in the ozone injection step S505, the ozone gas is injected into the chamber 11 through the inside of the evaporator 26, so that the hydrogen peroxide remaining in the evaporator 26 can be squeezed out into the chamber 11 using the ozone gas, thereby further improving the sterilization effect. In addition, as the sterilization device 100, regarding the inlet provided in the chamber 11, the inlet for introducing hydrogen peroxide and the inlet for introducing ozone gas can be shared, so that the peripheral structure of the chamber 11 can be simplified.

[0077] In addition, the sterilization step S500 includes a second steam preparation step S506 , a second steam injection step S507 , an external gas injection step S508 , and a second state maintaining step S509 .

[0078] The second steam preparation step S506 is a step for generating steam of the second aqueous solution to be injected in the next second steam injection step S507. The second steam preparation step S506 does not need to be performed after the ozone injection step S505 is completed, and can be performed before the second steam injection step S507 is started to prepare the steam of the second aqueous solution. The generation of the steam of the second aqueous solution can also be performed in the same steps as the generation of the steam of the first aqueous solution in the first steam preparation step S501.

[0079] First, the control unit 61 rotates the second tube pump 23b to draw the second aqueous solution from the second bottle 21b, and then injects a predetermined amount of aliquots into the storage unit 24. For example, when the treatment mode is the short mode, the concentration of hydrogen peroxide contained in the second aqueous solution is a predetermined concentration (x2) between 0.1 and 10%, and the predetermined amount is a predetermined amount (y2) between 2 and 8 ml. For example, when the predetermined amount is divided into two portions, the predetermined amount of aliquots is a predetermined amount (y2÷2) between 1 and 4 ml, which is half of y2. Next, the control unit 61 opens the first electromagnetic valve 70 for a constant time of 5 seconds, for example. Since the interior of the evaporator 26 has been depressurized, the second aqueous solution is instantly sucked into the evaporator 26. At this time, the storage unit 24 is connected to the atmosphere via the first filter 25, so the atmosphere enters the storage unit 24, and the second aqueous solution remaining in the storage unit 24, the first supply pipe 27, etc. is also sent to the evaporator 26. Next, the control unit 61 closes the first electromagnetic valve 70, and evaporates the second aqueous solution in the evaporator 26 for a constant time of, for example, 5 seconds. At this time, the evaporator 26 is constantly heated at a predetermined temperature between 65 and 120° C., for example. For example, if the amount of the second aqueous solution is adjusted and introduced so that it is almost completely evaporated, the pressure rises to the saturated vapor pressure level in the evaporator 26 having a predetermined volume between 0.5 and 2 L and a pressure of 50 Pa. After the second steam preparation step S506, the control unit 61 moves to the second steam injection step S507.

[0080] The second vapor injection step S507 is a step of injecting the vapor of the second aqueous solution generated in the evaporator 26 into the chamber 11. Figure 3 In the embodiment, the timing of starting the second steam injection step S507 is recorded as T14. Ozone alone is unlikely to contribute to sterilization, but the reactivity is increased by adding water. This is believed to be because, on the surface of bacteria, ozone reacts with water or residual hydrogen peroxide to generate OH radicals, etc., which effectively destroy the cell wall of the bacteria. Therefore, in the present embodiment, after the injection of ozone gas is completed, the steam of the second aqueous solution is immediately injected into the interior of the chamber 11. It is speculated that the hydrogen peroxide in the steam injected into the interior of the chamber 11 invades the bacterial cells from the cell wall destroyed by ozone and attacks the cell nucleus, thereby improving the sterilization effect.

[0081] Here, as a relationship between the first aqueous solution and the second aqueous solution, the concentration of hydrogen peroxide contained in the second aqueous solution may be lower than the concentration of hydrogen peroxide contained in the first aqueous solution.

[0082] The injection of the vapor of the first aqueous solution is positioned as the main sterilization treatment of the material using hydrogen peroxide as the sterilizing gas. On the other hand, the injection of the vapor of the second aqueous solution is positioned as an auxiliary treatment for improving the sterilization efficiency of the sterilization treatment based on the injection of ozone gas. Therefore, when the vapor of the second aqueous solution is injected in the second vapor injection step S507, the concentration of hydrogen peroxide contained in the aqueous solution can be set to be less than or the same as that of the first aqueous solution. Thus, in the sterilization method of this embodiment, even if both the first aqueous solution and the second aqueous solution are used, the amount of hydrogen peroxide used as the sterilization treatment as a whole can be reduced. In addition, by reducing the amount of hydrogen peroxide used, as a result, the amount of hydrogen peroxide that may remain on the surface of the sterilization object and inside the chamber 11 can also be proportionally reduced.

[0083] Alternatively, as a relationship between the first aqueous solution and the second aqueous solution, the total amount of hydrogen peroxide contained in the second aqueous solution may be less than the total amount of hydrogen peroxide contained in the first aqueous solution.

[0084] If the total amount of hydrogen peroxide contained in the second aqueous solution is less than the total amount of hydrogen peroxide contained in the first aqueous solution, the amount of hydrogen peroxide used in the overall sterilization process can be reduced even if the concentration of hydrogen peroxide contained in the second aqueous solution is higher than that in the first aqueous solution.

[0085] Alternatively, the concentration of hydrogen peroxide contained in the first aqueous solution or the second aqueous solution or the total amount of hydrogen peroxide contained in the first aqueous solution or the second aqueous solution may be specified based on the presence or absence of a lumen in the sterilization object or the material of the sterilization object.

[0086] In the present embodiment, three treatment modes are illustrated according to the presence or absence of a lumen of the sterilization object or the difference in the material of the sterilization object. For example, as a sterilization object that can be sterilized in the standard mode, a resin capillary can be listed. On the other hand, as a sterilization object that can be sterilized in the long mode, a stainless steel capillary can be listed. When the above-mentioned resin capillary and stainless steel capillary are compared, it is generally more difficult to sterilize the stainless steel capillary than the resin capillary. It is believed that this is because, for example, transition elements such as Fe, Mo or Cr contained in stainless steel have a high reactivity with hydrogen peroxide, so hydrogen peroxide is decomposed in the middle of the treatment, and it is difficult for sufficient hydrogen peroxide to reach the inside of the capillary. Or it is also believed that compared with the resin capillary, the stainless steel capillary has a higher thermal conductivity and is easy to cool under a reduced pressure environment, so hydrogen peroxide is easy to condense inside the capillary, and it is difficult for sufficient hydrogen peroxide to reach the inside of the capillary.

[0087] In this regard, according to the present embodiment, for example, when sterilizing a stainless steel capillary tube, it is possible to deal with it by making the concentration of hydrogen peroxide contained in the second aqueous solution higher than the concentration of hydrogen peroxide contained in the second aqueous solution in other treatment modes. However, even in this case, the concentration of hydrogen peroxide contained in the second aqueous solution does not exceed the concentration of hydrogen peroxide contained in the first aqueous solution. Alternatively, even if the concentration of hydrogen peroxide contained in the second aqueous solution is equal to the concentration of hydrogen peroxide contained in the first aqueous solution, the amount of the second aqueous solution input can be reduced. That is, when sterilizing a stainless steel capillary tube, there is a possibility that the total amount of hydrogen peroxide used (the total value of the concentration of hydrogen peroxide in the first aqueous solution and the second aqueous solution × the amount of hydrogen peroxide input) can be reduced in particular compared to the previous sterilization method. In this regard, the same is true when the total amount of hydrogen peroxide contained in the second aqueous solution is less than the total amount of hydrogen peroxide contained in the first aqueous solution, and the total amount of hydrogen peroxide used (the total value of the total amount of hydrogen peroxide in the first aqueous solution and the total amount of hydrogen peroxide in the second aqueous solution) can be reliably reduced.

[0088] It should be noted that if the concentration of hydrogen peroxide contained in the second aqueous solution is further increased, the sterilization effect is increased. In addition, setting the hydrogen peroxide contained in the second aqueous solution to a high concentration may also shorten the treatment time. Therefore, in the present embodiment, as an example, when the treatment mode is the long mode, the concentration of hydrogen peroxide contained in the second aqueous solution is set to a prescribed value (x1) between 30% and 60% of the concentration of hydrogen peroxide contained in the first aqueous solution. On the other hand, the input amount per pulse is a prescribed value (y2) between 2 and 8 ml in the short mode and the standard mode, whereas in the long mode, it can be set to a lower value such as a prescribed amount (y3) between 1 and 5 ml.

[0089] As described above, the second vapor injection step S507 is performed immediately after the ozone injection step S505 is completed. The injection of the vapor of the second aqueous solution may be performed in the same procedure as the injection of the vapor of the first aqueous solution in the first vapor injection step S502.

[0090] First, the control unit 61 opens the second solenoid valve 71 and the third solenoid valve 72 for a constant time of, for example, 10 seconds, and injects the vapor of the second aqueous solution into the chamber 11. Next, the control unit 61 closes the second solenoid valve 71 and the third solenoid valve 72. Then, the control unit 61 repeatedly injects the vapor of the second aqueous solution in the same steps according to the processing mode. Here, when the processing mode is the short mode, the control unit 61 may, for example, evaporate the second aqueous solution twice and evaporate half of y2 (2 to 8 ml) each time, and inject it into the chamber 11 each time. Alternatively, the control unit 61 may further inject the vapor of the second aqueous solution in multiple times. After the second vapor injection step S507, the control unit 61 moves to the external gas injection step S508.

[0091] In the description so far, in the second steam injection step S507, the steam of the second aqueous solution of hydrogen peroxide is injected, but it is also possible to inject steam generated by water or a solution containing volatile components as shown below instead of the second aqueous solution. First, the water that generates steam at this time can be water from which pyrogens are removed or inactivated, or water from which bacteria or microorganisms are removed or inactivated. By using water from which pyrogens are removed or inactivated, or water from which bacteria or microorganisms are removed or inactivated, contamination of the sterilization object caused by pyrogens, etc. can be suppressed in advance. It should be noted that the water mentioned here can be pure water or ultrapure water such as distilled water that has been sterilized or sterilized. In addition, it can also be pure water, water from which scale is removed, or water from top water. By using pure water or water from which scale is removed, it is possible to eliminate adverse effects (for example, clogging, etc.) mainly caused by scale on the evaporator 26 and efficiently generate steam. As water from which scale is removed, filtered water from which scale crystals are removed, soft water from which cations that cause scale are removed, etc. can be exemplified. Compared with pure water and water from which scale has been removed, the upper water is easy to obtain and does not require pretreatment. In addition, the volatile component may be sodium hypochlorite or alcohol. The alcohol may be ethanol, for example. Sodium hypochlorite or alcohol has a bactericidal effect, so by injecting the steam of a solution containing such a volatile component, the sterilization efficiency can be further improved.

[0092] For example, if pure water vapor is injected instead of the second aqueous solution in the second vapor injection step S507, pure water is stored in the second bottle 21b. Then, pure water is evaporated in the evaporator 26. Even if pure water is used instead of the second aqueous solution, the reactivity of the ozone gas described above can be effectively improved. Figure 3In the example of the table shown, in the short mode and the standard mode, the concentration of hydrogen peroxide contained in the second aqueous solution (x2, a predetermined value between 0.1% and 10%) is significantly lower than the concentration of hydrogen peroxide contained in the first aqueous solution (x1, a predetermined value between 30% and 60%). Therefore, for example, when any of the two treatment modes can be selected and the sterilization object is not excessively required to have a sterilization effect, pure water can be used instead of the second aqueous solution. As a result, the amount of hydrogen peroxide used can be reduced as a whole in the sterilization process.

[0093] The external gas injection step S508 is a step of injecting external gas such as air or dry nitrogen into the chamber 11. Figure 3 In the embodiment, the timing of starting the external gas injection step S508 is recorded as T15. In the present embodiment, as an example, the external gas is the atmosphere. The external gas injection step S508 is performed immediately after the second steam injection step S507 is completed. By injecting the atmosphere into the interior of the chamber 11, for example, hydrogen peroxide and ozone gas that are stagnant in the lumen of the sterilization object having a lumen are pressed in, and sterilization is further promoted. In addition, by injecting the atmosphere into the interior of the chamber 11, the concentration distribution of the gas present in the interior of the chamber 11 is uniformized, and sterilization can be performed uniformly. In addition, when the atmosphere is injected into the interior of the chamber 11, the internal pressure rises, and the hydrogen peroxide in the steam is slightly condensed on the surface of the sterilization object, so the sterilization effect is improved. The condensation here is sometimes also referred to as micro condensation. In particular, when the external gas is the atmosphere, the raw material cost of the injected gas is not spent, and the structure for injecting the atmosphere into the interior of the chamber 11 can also be simplified, so that the increase in the manufacturing cost of the sterilization device 100 can be suppressed.

[0094] The control unit 61 injects the atmosphere into the interior of the chamber 11 via the atmosphere introduction unit 50. Specifically, the control unit 61 adjusts the injection amount of the atmosphere introduced through the second filter 51 by appropriately controlling the opening and closing of the ninth solenoid valve 78 and the tenth solenoid valve 79. At this time, the atmosphere is injected until a certain pressure is reached. In the present embodiment, the control unit 61 injects the atmosphere until the pressure inside the chamber 11 becomes about 90% of the atmospheric pressure, that is, about 90 kPa, and then closes the ninth solenoid valve 78 and the tenth solenoid valve 79. This is because if the internal pressure of the chamber 11 is the same as the external pressure, there is a possibility that the gas leaks from the sealed portion of the door 12 to the outside. After the external gas injection step S508, the control unit 61 moves to the second state maintaining step S509.

[0095] Thus, the external gas injection step S508 is particularly effective when the standard mode or the long mode is selected for the case where the sterilization object has a lumen. On the other hand, in the case of the short mode where the sterilization object does not have a lumen and the surface of the sterilization object is mainly sterilized, the external gas injection step S508 may also be performed from the viewpoint of simplifying the process contents as long as the desired sterilization effect can be obtained.

[0096] The second state maintaining step S509 is a step of maintaining the state inside the chamber 11 for a certain period of time after the external gas injection step S508 is completed. Figure 3 In the process, the period of holding the constant time is recorded as H15. By keeping the state of the interior of the chamber 11 constant for such a time, the sterilization effect described in the external gas injection step S508 is further promoted. The holding time here is different for each treatment mode. The holding time in the case of the short mode is, for example, 2 minutes. The holding time in the case of the standard mode is, for example, 3 minutes. The holding time in the case of the long mode is, for example, 5 minutes.

[0097] The sterilization process S500 thus far may be repeated as many times as required according to the sterilization object. Figure 2 As shown, it is determined whether the sterilization process S500 (S600) needs to be repeated. One sterilization process S500 is counted as one exposure number, and the exposure number is recorded as the number of pulses below. Here, when the control unit 61 determines that the sterilization process S500 is still required (yes), it moves to the sterilization decompression process S400 to decompress and perform the sterilization process of the second pulse. On the other hand, when the control unit 61 determines that no further sterilization process is required (no), it moves to the next ventilation process S700.

[0098] Here, the number of pulses required to achieve 10 -6 Sterility assurance level (SAL<10 -6 It should be noted that in order to achieve this level, the condition is: in the sterilization process equivalent to half a pulse, 10 -6 All indicator bacteria above 100 are killed. In this embodiment, as an example, two pulses are set as the entire cycle in all three treatment modes. In addition, the sterilization step S500 may be repeated for a predetermined number of times without determining whether it needs to be repeated.

[0099] The ventilation step S700 is a step of reducing the pressure inside the chamber 11 to a certain vacuum degree to remove hydrogen peroxide and ozone as sterilizing gases, and then injecting air until the pressure approaches the atmospheric pressure to dilute the sterilizing gas. In this embodiment, the process in the ventilation step S700 is different when the treatment mode is the short mode and when it is in other modes.

[0100] First, the process in the ventilation step S700 when the treatment mode is the short mode is described. In the short mode, the contact time between the sterilizing gas and the sterilization object is shorter than in other modes. Therefore, the ventilation step S700 in this case includes the following treatment steps in order to shorten the treatment time.

[0101] First, after the second state maintaining step S509 is completed, the control unit 61 starts the vacuum pump 41 as quickly as possible and opens the eighth electromagnetic valve 77 to start decompressing the interior of the chamber 11. At the same time, the control unit 61 opens the second electromagnetic valve 71, the third electromagnetic valve 72 and the seventh electromagnetic valve 76 to discharge the residual gas inside the evaporator 26 and the buffer tank 34. In the short mode, the decompression is continued until the pressure inside the chamber 11 reaches, for example, 100 Pa. The discharged sterilizing gas passes through the first catalyst tank 42 and the second catalyst tank 43, so that hydrogen peroxide is decomposed into harmless water and oxygen, and on the other hand, ozone is decomposed into harmless oxygen, so that it is exhausted to the outside of the sterilization device 100 at a concentration below the safety management value. Next, the control unit 61 closes the eighth electromagnetic valve 77 after the pressure inside the chamber 11 reaches the predetermined decompression pressure.

[0102] Next, the control unit 61 opens the ninth solenoid valve 78 and the tenth solenoid valve 79, and injects the atmosphere into the chamber 11 through the second filter 51. At the same time, the control unit 61 opens the second solenoid valve 71, the third solenoid valve 72, and the seventh solenoid valve 76, and injects the atmosphere into the evaporator 26 and the buffer tank 34. The injected atmosphere diffuses and dilutes the gas remaining in the chamber 11, and removes the sterilization gas attached to the sterilization object and the inner surface of the chamber 11. Next, the control unit 61 injects the atmosphere until the pressure inside the chamber 11 reaches about 90% of the atmospheric pressure, that is, about 90 kPa, and then closes the ninth solenoid valve 78 and the tenth solenoid valve 79.

[0103] Then, the control unit 61 repeats such decompression and atmospheric injection for a predetermined number of times. In the case of the short mode, for example, it can be repeated three times in total. For the ventilation process S700 in this case, if the time spent on decompression is set to about 3 minutes and the time spent on atmospheric injection is set to about 0.5 minutes, it will take about 3.5 minutes × 3 times = 10.5 minutes. After repeating the decompression and atmospheric injection for a predetermined number of times, the control unit 61 returns the interior of the chamber 11 to atmospheric pressure by atmospheric injection, and ends the ventilation process S700. After the ventilation process S700, the control unit 61 ends the sterilization process.

[0104] Next, the processing in the ventilation step S700 when the treatment mode is a mode other than the short mode is described. In the treatment mode other than the short mode, the contact time between the sterilization gas and the sterilization object is long, or the amount of hydrogen peroxide attached to the sterilization object and the amount of hydrogen peroxide remaining in the chamber 11 is large. Therefore, the ventilation step S700 in this case includes, for example, the following processing steps.

[0105] First, the basic actions of decompression and atmospheric injection are the same as when the treatment mode is the short mode. However, in the short mode, the pressure reached during decompression is set to, for example, 100 Pa or less. In contrast, in modes other than the short mode, since the sterilization object may include a lumen, the pressure reached during decompression is set to, for example, 50 Pa or less as a stricter condition than in the short mode.

[0106] Next, after the first decompression and atmospheric injection are completed, the control unit 61 then performs decompression while atmospheric injection. Specifically, the control unit 61 starts the vacuum pump 41 and opens the eighth electromagnetic valve 77 to start decompression, and then opens the ninth electromagnetic valve 78 and the tenth electromagnetic valve 79, for example, with a delay of 2 seconds, and performs atmospheric injection through the second filter 51. Here, the timing of stopping atmospheric injection each time after decompression is assumed to be when the pressure inside the chamber 11 becomes about 90kPa or more. In this case, the timing of stopping atmospheric injection each time decompression is performed while atmospheric injection is performed can be set to when the pressure inside the chamber 11 becomes about 90kPa or less. By exhausting the air while performing atmospheric injection like this, the flow of the atmosphere is activated, and the sterilizing gas attached to the sterilization object and the inner surface of the chamber 11 is actively removed. In particular, in the usual sterilization process, the sterilization object is packaged by packaging materials, so it is effective to remove the sterilizing gas adsorbed on the packaging materials. The time for decompression while performing atmospheric injection here is set to, for example, about 5 minutes. In this case, the time required for one process of exhausting the gas while injecting the atmosphere is shorter than that for one process of injecting the atmosphere after reducing the pressure, and thus, the time required for the entire ventilation step S700 can be shortened.

[0107] Then, the control unit 61 further repeats the same operation as the decompression and atmospheric injection performed initially. In this case, for example, the operation may be repeated twice.

[0108] For the ventilation process S700 in this case, the time spent on the first decompression and atmospheric injection is 3.5 minutes, the time spent on the decompression while atmospheric injection is 5 minutes, and the time spent on the second decompression and atmospheric injection is 3.5 minutes × 2 = 7 minutes, which is a total of 15.5 minutes. Then, the control unit 61 returns the interior of the chamber 11 to atmospheric pressure by atmospheric injection, and ends the ventilation process S700. After the ventilation process S700, the control unit 61 ends the sterilization process.

[0109] It should be noted that in the ventilation process S700, the decompression and atmospheric injection are repeated multiple times as described above. Although the more times the repetitions are repeated, the more effective the removal of the residual sterilizing gas is, the longer the processing time becomes. Therefore, for example, in the case where the decompression and atmospheric injection are repeated five times, a time shorter than the time spent on two repetitions of the five times, for example, 5 minutes shorter than (3 minutes × 2 times), that is, 6 minutes, can be replaced with the next repetition of one time. In this way, the sterilizing gas remaining in the interior of the chamber 11 can be discharged more efficiently, and the time required for the ventilation process S700 can also be shortened.

[0110] The processing time of the sterilization process in the above embodiment is roughly as follows for each processing mode: Figure 3 After a series of sterilization processes are completed, the operator takes the sterilization object out of the chamber 11 .

[0111] Next, the effects of the sterilization method of this embodiment and the sterilization apparatus 100 capable of implementing the sterilization method will be described.

[0112] The sterilization method of this embodiment includes a pre-decompression step S200, in which the interior of the chamber 11 is decompressed relative to atmospheric pressure after the sterilization object packaged by the packaging material is placed in the chamber 11, and the packaging material uses a material that absorbs ozone gas and hydrogen peroxide. The sterilization method includes an ozone adsorption step S300, in which ozone gas is injected into the interior of the chamber 11 under the decompression of the pre-decompression step S200, and the ozone gas is adsorbed on the packaging material. In addition, the sterilization method includes a sterilization step S500, in which the sterilization object is sterilized using ozone gas and hydrogen peroxide after the ozone adsorption step S300.

[0113] On the other hand, the sterilization device 100 for sterilizing the sterilization object of the present embodiment includes a chamber 11, which contains the sterilization object packaged by a packaging material, and the packaging material uses a material that absorbs ozone gas and hydrogen peroxide. The sterilization device 100 includes an evaporator 26, which is connected to the chamber 11 and evaporates and fills an aqueous solution of hydrogen peroxide, water from which pyrogens are removed or inactivated, water from which bacteria or microorganisms are removed or inactivated, pure water, water from which scale is removed, water, or a solution containing volatile components. The sterilization device 100 includes an ozone generator 32, which is connected to the chamber 11 and generates ozone gas. In addition, the sterilization device 100 includes a control unit 61, which controls the injection of steam generated in the evaporator 26 or ozone gas generated in the ozone generator 32 into the interior of the chamber 11. Here, the control unit 61 depressurizes the interior of the chamber 11 , injects ozone gas into the interior of the chamber 11 under the depressurized pressure, and sterilizes the sterilization target object using the ozone gas and hydrogen peroxide.

[0114] Thus, in the present embodiment, first, in the sterilization step S500, ozone gas and hydrogen peroxide are used to sterilize the sterilization object, so that, for example, the sterilization efficiency is higher than when only hydrogen peroxide is used for sterilization. In addition, in the present embodiment, before the sterilization step S500, ozone gas is injected into the interior of the chamber 11 under reduced pressure as an ozone adsorption step S300, and the ozone gas is adsorbed on the packaging material that packages the sterilization object. That is, in the present embodiment, before the injection of ozone gas in the sterilization step S500, ozone gas is adsorbed on the packaging material, so the packaging material becomes saturated. Therefore, when ozone gas is injected into the interior of the chamber 11 in the sterilization step S500, it is difficult for ozone gas to react with the packaging material, so that the ozone gas easily passes through the packaging material and reaches the sterilization object. As a result, according to the present embodiment, the reduction in sterilization efficiency caused by adsorption of ozone gas in the sterilization step S500 can be suppressed in advance, so that, for example, as a whole, the sterilization efficiency is improved compared to the case where the sterilization object is sterilized only by the sterilization step S500.

[0115] Therefore, according to the sterilization method and the sterilization apparatus of the present embodiment, the sterilization efficiency can be improved as the entire sterilization process.

[0116] In addition, the sterilization method of this embodiment may include a sterilization decompression step S400 of decompressing the interior of the chamber 11 after the ozone adsorption step S300. In this case, the sterilization step S500 may also be performed under the decompression of the sterilization decompression step S400.

[0117] In the ozone adsorption step S300, when ozone gas is injected into the interior of the chamber 11, the gas supplied into the interior of the chamber 11 also contains gas other than ozone gas. Moreover, the gas other than ozone gas is generally oxygen in most cases. Here, if oxygen remains in the interior of the chamber 11 during the subsequent sterilization step S500, it may also hinder the sterilization process. In this regard, according to the sterilization method including the sterilization decompression step S400, such residual gas can be removed in advance before the sterilization step S500.

[0118] In addition, in the sterilization method of the present embodiment, the sterilization process may include a first steam injection step S502 of injecting steam generated from a first aqueous solution of hydrogen peroxide into the interior of the chamber 11. The sterilization process may include an ozone injection step S505 of injecting ozone gas into the interior of the chamber 11 after the first steam injection step S502. Furthermore, the sterilization process may include a second steam injection step S507 of injecting steam generated from a second aqueous solution of hydrogen peroxide into the interior of the chamber 11. The steam injected in the second steam injection step S507 may be steam generated from water from which pyrogens have been removed or inactivated, water from which bacteria or microorganisms have been removed or inactivated, pure water, water from which scale has been removed, water from top water, or a solution containing volatile components, instead of steam generated from the second aqueous solution.

[0119] According to such a sterilization method, after the sterilization treatment using the steam of the first aqueous solution is carried out on the sterilization object, the sterilization treatment using ozone gas is carried out. At this time, in the present embodiment, after the ozone gas is injected into the interior of the chamber 11, the steam of the second aqueous solution is further injected. As a result, the reactivity of the ozone gas can be improved, so in the sterilization treatment using the ozone gas, the sterilization efficiency is good compared with the case where the sterilization treatment is carried out using the ozone gas alone. On the other hand, even if the steam generated by water from which pyrogens have been removed or inactivated, water from which bacteria or microorganisms have been removed or inactivated, pure water, water from which scale has been removed, water from above, or a solution containing volatile components is used instead of the steam of the second aqueous solution, the same effect is achieved. For example, by using water from which pyrogens have been removed or inactivated, or water from which bacteria or microorganisms have been removed or inactivated, the contamination of the sterilization object caused by pyrogens, bacteria or microorganisms can be suppressed in advance.

[0120] In addition, in the sterilization method of the present embodiment, the ozone generator 32 that generates the ozone gas in the ozone injection step S505 may be used to generate the ozone gas in the ozone adsorption step S300.

[0121] According to such a sterilization method, the ozone gas used in the ozone adsorption step S300 and the ozone gas used in the ozone injection step S505 can be the same gas with the same concentration, for example. This simplifies the condition setting of the sterilization method and simplifies the structure of the sterilization apparatus 100 for performing the sterilization method.

[0122] In the sterilization method of this embodiment, the pressure inside the chamber 11 when ozone gas is injected in the ozone adsorption step S300 may be higher than the pressure inside the chamber 11 when steam generated from the first aqueous solution is injected in the first steam injection step S502.

[0123] According to such a sterilization method, the time until the pressure inside the chamber 11 reaches the value when the ozone gas is injected in the ozone adsorption step S300 can be further shortened. Thus, the operation time of the sterilization apparatus 100 for performing the sterilization method can be further shortened.

[0124] In the sterilization method of the present embodiment, the gas supplied into the chamber 11 in the ozone adsorption step S300 may contain ozone gas and oxygen and be oxygen-enriched.

[0125] According to such a sterilization method, it is possible to achieve an effect of improving the sterilization efficiency as a whole in the sterilization process, and to suppress the generation or use of ozone gas more than necessary.

[0126] Thus, the present invention naturally includes various embodiments and the like not described here.

[0127] Description of Reference Numerals

[0128] 10: Chamber unit, 11: Chamber, 12: Door, 13: First heater, 14: First pressure gauge, 20: Hydrogen peroxide supply unit, 21: Bottle, 22: Extraction pipe, 22a: First extraction pipe, 22b: Second extraction pipe, 23: Tube pump, 23a: First tube pump, 23b: Second tube pump, 24: Storage unit, 25: First filter, 26: Evaporator, 27: First supply pipe, 28: Injection pipe, 28a: First injection pipe, 28b: Second injection pipe, 29: Second heater, 30: Ozone supply unit, 31: Oxygen generator, 32: Ozone generator, 33: Ozone concentration meter, 34: Buffer tank, 35: Second pressure gauge, 36: Second supply Supply piping, 37: third supply piping, 38: exhaust piping, 39: pressure sensor, 40: exhaust unit, 41: vacuum pump, 42: first catalyst tank, 43: second catalyst tank, 44: third heater, 45: fourth heater, 50: atmosphere introduction unit, 51: second filter, 52: first introduction port, 53: second introduction port, 60: control unit, 61: control unit, 62: touch panel, 70: first solenoid valve, 71: second solenoid valve, 72: third solenoid valve, 73: fourth solenoid valve, 74: fifth solenoid valve, 75: sixth solenoid valve, 76: seventh solenoid valve, 77: eighth solenoid valve, 78: ninth solenoid valve, 79: tenth solenoid valve, 100: sterilization device.

Claims

1. A sterilization method, wherein: The sterilization method comprises: A pre-decompression step of decompressing the interior of the chamber relative to atmospheric pressure after the sterilization object packaged with the packaging material is placed in the chamber, wherein the packaging material is made of a material that absorbs ozone gas and hydrogen peroxide; an ozone adsorption step of injecting ozone gas into the interior of the chamber under the reduced pressure of the pre-decompression step and allowing the ozone gas to be adsorbed on the packaging material; a sterilization and decompression step of decompressing the interior of the chamber after the ozone adsorption step; and The sterilization step is to sterilize the object to be sterilized using ozone gas and hydrogen peroxide under reduced pressure in the sterilization reduced pressure step.

2. The sterilization method according to claim 1, wherein: The pre-decompression step and the ozone adsorption step are performed once, and then the sterilization decompression step and the sterilization step are repeated a required number of times.

3. The sterilization method according to claim 1 or 2, wherein: The sterilization process comprises: a first steam injection step of injecting steam generated from a first aqueous solution of hydrogen peroxide into the chamber; The ozone injection step is to inject ozone gas into the interior of the chamber after the first steam injection step.

4. The sterilization method according to claim 3, wherein: The sterilization process includes the following second steam injection process: after the ozone injection process, steam generated by a second aqueous solution of hydrogen peroxide, water from which pyrogens are removed or inactivated, water from which microorganisms are removed or inactivated, water from which scale is removed, top water, or a solution containing volatile components is injected into the interior of the chamber.

5. The sterilization method according to claim 3, wherein: The ozone gas in the ozone adsorption step is generated by an ozone generator that generates the ozone gas in the ozone injection step.

6. The sterilization method according to claim 3, wherein: The pressure inside the chamber when ozone gas is injected in the ozone adsorption step is higher than the pressure inside the chamber when steam generated from the first aqueous solution is injected in the first steam injection step.

7. The sterilization method according to claim 5, wherein: The ozone gas in the ozone adsorption step is injected into the chamber from a buffer tank communicated with the ozone generator.

8. A sterilization device for sterilizing an object to be sterilized, wherein: The sterilizing device comprises: a chamber that accommodates the sterilization object packaged by a packaging material, wherein the packaging material is made of a material that absorbs ozone gas and hydrogen peroxide; an evaporator which is in communication with the chamber and evaporates and fills an aqueous solution of hydrogen peroxide, water from which pyrogens have been removed or inactivated, water from which microorganisms have been removed or inactivated, water from which scale has been removed, top water, or a solution containing volatile components; an ozone generator, which is in communication with the chamber and generates ozone gas; and A control unit controls the injection of the steam generated in the evaporator or the ozone gas generated in the ozone generator into the interior of the chamber, thereby depressurizing the interior of the chamber and injecting the ozone gas into the interior of the chamber under the reduced pressure, and then depressurizing the interior of the chamber and injecting hydrogen peroxide and ozone gas into the interior of the chamber under the reduced pressure to sterilize the sterilization object.

Images