JP2022020554A - Active oxygen supply device, processing device using active oxygen and processing method using active oxygen - Google Patents

Abstract

To provide an active oxygen supply device capable of more efficiently supplying active oxygen to a surface of a processed object, a processing device using active oxygen, capable of more efficiently processing the surface of the processed object, with active oxygen, and a processing method for more efficiently processing the surface of the processed object with the active oxygen.SOLUTION: An active oxygen supply device comprises a plasma actuator provided with a plasma generator and an ultraviolet light source in a housing having at least one opening. The plasma generator is provided with a first electrode and a second electrode sandwiching a dielectric substance therebetween, and by applying a voltage between both the electrodes, an induction flow including ozone is generated. The plasma actuator is arranged so that, the induction flow flows outward of the housing, from the opening, the ultraviolet light source radiates the ultraviolet to the induction flow, and in the induction flow, active oxygen is generated. There are also provided a processing device using the active oxygen, and a processing method using the active oxygen.SELECTED DRAWING: Figure 1

Description

The present disclosure is directed to an active oxygen supply device, a treatment device using active oxygen, and a treatment method using active oxygen.

Ultraviolet rays and ozone are known as means for sterilizing articles and the like. Patent Document 1 uses a sterilizer having an ozone supply device, an ultraviolet generation lamp, and a stirrer to solve the problem that sterilization by ultraviolet rays is limited to a portion of the object to be sterilized that is irradiated with ultraviolet rays. Discloses a method of sterilizing the shadow portion of a sample by stirring active oxygen generated by irradiating ozone with ultraviolet rays generated by an ultraviolet ray generating lamp.

Japanese Unexamined Patent Publication No. 1-25865

When the present inventors examined the sterilization performance by the sterilization method according to Patent Document 1, there were cases where the sterilization performance was equivalent to that of the conventional sterilization method using only ozone. It is said that the sterilizing ability of active oxygen is far higher than the sterilizing ability of ozone, but such a study result was unexpected.
One aspect of the present disclosure is an active oxygen supply device capable of more efficiently supplying active oxygen to the surface of the object to be treated, a treatment device using active oxygen capable of more efficiently treating the surface of the object to be treated with active oxygen, and the like. Further, the present invention aims at providing a treatment method using active oxygen, which can treat the surface of the object to be treated with active oxygen more efficiently.

According to at least one aspect of the present disclosure, a plasma generator and an ultraviolet light source are provided in a housing having at least one opening, and the plasma generator has a first electrode and a second electrode with a dielectric interposed therebetween. It is a plasma actuator that generates an induced flow containing ultraviolet rays by providing an electrode of the above and applying a voltage between both electrodes, and the plasma actuator is arranged so that the induced flow flows out of the housing through the opening. The ultraviolet light source is provided with an active oxygen supply device that irradiates the induced flow with ultraviolet rays to generate active oxygen in the induced flow.

Further, according to at least one aspect of the present disclosure, it is a processing device for treating the surface of the object to be treated with active oxygen, and is provided with a plasma generator and an ultraviolet light source in a housing having at least one opening. The plasma generator is a plasma actuator in which a first electrode and a second electrode are provided with a dielectric sandwiched between them, and an induced flow containing ultraviolet rays is generated by applying a voltage between the two electrodes. Is arranged so that the induced flow flows out of the housing through the opening, and the ultraviolet light source is due to active oxygen that irradiates the induced flow with ultraviolet rays and generates active oxygen in the induced flow. Processing equipment is provided.

Further, according to at least one aspect of the present disclosure, it is a treatment method for treating the surface of the object to be treated with active oxygen.
A plasma generator and an ultraviolet light source are provided in a housing having at least one opening, and the plasma generator is provided with a first electrode and a second electrode with a dielectric interposed therebetween, and a voltage is applied between the two electrodes. It is a plasma actuator that generates an induced flow containing ozone by applying it.
The plasma actuator is arranged so that the induced flow flows out of the housing through the opening, and the ultraviolet light source irradiates the induced flow with ultraviolet rays to generate active oxygen in the induced flow. The step of preparing a treatment device using active oxygen, the relative treatment device using the active oxygen, and the object to be treated are exposed to the surface of the object to be treated when the induced flow is discharged from the opening. A treatment method using active oxygen is provided, which comprises a step of placing the induced flow in a specific position and a step of allowing the induced flow to flow out from the opening and treating the surface of the object to be treated with active oxygen.

According to one aspect of the present disclosure, an active oxygen supply device capable of more efficiently supplying active oxygen to the surface of the object to be treated, and treatment with active oxygen capable of more efficiently treating the surface of the object to be treated with active oxygen. It is possible to obtain a treatment method using active oxygen, which can treat the surface of the apparatus and the object to be treated more efficiently with active oxygen.

The schematic sectional view showing the structure of the active oxygen supply apparatus which concerns on one aspect of this disclosure. The schematic cross-sectional view which shows the structure of the plasma generator which concerns on one aspect of this disclosure. Explanatory drawing of plasma actuator which concerns on one aspect of this disclosure. Dimensional explanatory drawing explanatory drawing of the active oxygen supply apparatus which concerns on one aspect of this disclosure. The plan view of the active oxygen supply apparatus which concerns on another aspect of this disclosure. FIG. 5 is a sectional view taken along line AA of FIG. The schematic explanatory view of the processing method using the active oxygen supply apparatus which concerns on another aspect of this disclosure.

Hereinafter, embodiments for carrying out this disclosure will be specifically exemplified with reference to the drawings. However, the dimensions, materials, shapes, etc. of the components described in this form should be appropriately changed depending on the composition of the members to which the disclosure is applied and various conditions. That is, it is not intended to limit the scope of this disclosure to the following forms.
Further, in the present disclosure, the description of "XX or more and YY or less" or "XX to YY" indicating a numerical range means a numerical range including a lower limit and an upper limit which are end points, unless otherwise specified. When numerical ranges are described step by step, the upper and lower limits of each numerical range can be arbitrarily combined.

In addition, the term "bacteria" as an object of "eradication" according to the present disclosure refers to microorganisms, which include fungi, bacteria, unicellular algae, viruses, protozoa, etc., as well as animal or plant cells ( Includes stem cells, dedifferentiated cells, differentiated cells), tissue cultures, fusion cells obtained by genetic engineering (including hybridomas), dedifferentiated cells, and transformants (microorganisms). Examples of viruses include norovirus, rotavirus, influenza virus, adenovirus, coronavirus, measles virus, ruin virus, hepatitis virus, herpesvirus, HIV virus and the like. Examples of bacteria include staphylococci, Escherichia coli, salmonella, pyogenic, cholera, shigella, charcoal, tuberculosis, botulinum, tetanus, and streptococcus. Further, examples of fungi include Trichophyton, Aspergillus, Candida and the like.

Further, in the following description, configurations having the same function may be numbered the same in the drawings, and the description thereof may be omitted.
Furthermore, in the present specification, the active oxygen supply device of the present disclosure and the treatment device using the active oxygen of the present disclosure are collectively referred to simply as "active oxygen supply device".

According to the studies by the present inventors, the reason why the sterilizing ability of the sterilizing apparatus according to Patent Document 1 is limited is presumed as follows.
Patent Document 1 excites ozone by irradiating it with ultraviolet rays to generate active oxygen having extremely high sterilizing power. Here, active oxygen is a general term for highly reactive oxygen-active species such as superoxide anion radical (・_О2- ⁾ and hydroxyl radical (・ ОH), and due to its high reactivity, bacteria and viruses. Can be oxidatively decomposed immediately.

However, since ozone absorbs ultraviolet rays very well, it is considered that the generation of active oxygen is limited to the vicinity of the ultraviolet generation lamp in the sterilizer according to Patent Document 1. That is, it is considered that the ultraviolet rays do not sufficiently reach the ozone existing at a position away from the ultraviolet generation lamp, and it is difficult to generate active oxygen at a place away from the ultraviolet generation lamp.
In addition, active oxygen is extremely unstable, with an extremely short _half ^- life of ^10-6 seconds for О2- and ^10-9 seconds for ОH, and it is quickly converted to stable oxygen and water. .. Therefore, it is considered difficult to passively fill the inside of the main body of the sterilizer with the active oxygen generated in the vicinity of the ultraviolet generation lamp. In other words, it is considered that the sterilization by the sterilization method according to Patent Document 1 is substantially performed by ozone. Therefore, it is considered that the sterilization performance by the sterilization method according to Patent Document 1 is about the same as the sterilization performance by the conventional sterilization method using only ozone.
Based on these considerations, the present inventors need to more actively place the object to be treated and the surface to be treated in an active oxygen atmosphere in order to treat the object to be treated with active oxygen having a short life. Recognized that. As a result of studies by the present inventors based on this recognition, it has been found that the object to be treated can be more actively placed in an active oxygen atmosphere according to the active oxygen supply device described below. In the present disclosure, the "treatment" of the object to be treated with active oxygen includes activities such as surface modification (hydrophilization treatment), sterilization, deodorization, and bleaching of the surface of the object to be treated with active oxygen. It shall include all treatments that can be achieved with oxygen.

Hereinafter, the active oxygen supply device 101 according to one aspect of the present disclosure will be described with reference to FIG. The active oxygen supply device 101 according to one aspect of the present disclosure includes an ultraviolet light source 102 and a plasma generator 103 in a housing 107 having at least one opening 106.
The ultraviolet light source 102 irradiates the induced flow 105 with ultraviolet rays to generate active oxygen in the induced flow 105. In FIG. 1, reference numeral 104 is an object to be processed.

Further, FIG. 2 shows a cross-sectional structure of one aspect of the plasma generator 103. In the plasma generator, the first electrode 203 is on one surface of the dielectric 201 (hereinafter, also referred to as “first surface”), and the surface opposite to the first surface (hereinafter, “second surface”). A second electrode 205 is provided in a so-called dielectric barrier discharge (DBD) plasma actuator (hereinafter, may be simply referred to as “DBD-PA”). In FIG. 2, reference numeral 206 is a dielectric substrate and reference numeral 207 is a power supply.
In the plasma generator 103, the first electrode 203 and the second electrode 205 arranged so as to sandwich the dielectric 201 are arranged so as to be obliquely opposite to each other. By applying a voltage between these electrodes (between both electrodes), plasma 202 is generated from the first electrode 203 toward the second electrode 205, and the dielectric 201 is generated from the edge 204 of the first electrode 203. A jet-like flow is induced by the surface plasma 202 along the exposed portion (the portion not covered with the first electrode) 21-1 of the first surface of the above. At the same time, an air suction flow from the space inside the container toward the electrodes is also generated. The electrons in the surface plasma 202 collide with oxygen molecules in the air and dissociate the oxygen molecules to generate oxygen atoms. The generated oxygen atoms collide with undissociated oxygen molecules to generate ozone. Therefore, due to the action of the jet-like flow by the surface plasma 202 and the suction flow of air, an induced flow 105 containing a high concentration of ozone is generated from the edge 204 of the first electrode 203 along the surface of the dielectric 201. do.
The plasma generator 103 is arranged so that the induced flow 105 flows out of the housing 107 from the opening 106 and is supplied to the treated surface 104-1 of the object to be processed 104.

That is, in the active oxygen supply device according to one aspect of the present disclosure, the induced flow 105 containing ozone from the plasma generator 103 flows out of the housing 107 from the opening 106, and the treated surface 104 of the object to be treated 104. -1, the ultraviolet light source 102 irradiates the induced flow 105 with ultraviolet rays to generate active oxygen in the induced flow 105, whereby the region near the treated surface 104-1, specifically, high from the treated surface, for example. Active oxygen can be actively supplied to a spatial region (hereinafter, also referred to as "surface region") up to about 1 mm. Therefore, the active oxygen can be supplied to the surface of the object to be treated before the generated active oxygen is converted into oxygen and water. As a result, the treated surface 104-1 of the object to be treated 104 is more reliably treated with active oxygen.

<Electrodes and dielectrics>
The material constituting the first electrode and the second electrode is not particularly limited as long as it is a material having good conductivity. For example, metals such as copper, aluminum, stainless steel, gold, silver, and platinum, and plated or vapor-deposited materials, conductive carbon materials such as carbon black, graphite, and carbon nanotubes, and resin. A mixed composite material or the like can be used. The material constituting the first electrode and the material constituting the second electrode may be the same or different.
Among these, from the viewpoint of avoiding corrosion of the electrode and achieving uniform discharge, the material constituting the first electrode is preferably aluminum, stainless steel or silver. For the same reason, the material constituting the second electrode is also preferably aluminum, stainless steel or silver.
Further, the shapes of the first electrode and the second electrode may be flat plate-shaped, wire-shaped, needle-shaped or the like without particular limitation. Preferably, the shape of the first electrode is flat plate. Further, preferably, the shape of the second electrode is a flat plate. When at least one of the first electrode and the second electrode has a flat plate shape, the aspect ratio (length of long side / length of short side) of the flat plate is preferably 2 or more.
It is also preferable, but not limited to, that the first electrode and at least one of the second electrodes have an apex angle of 45 ° or less (that is, the electrodes are sharp). Although the drawings show the case where the apex angle of both the first electrode and the second electrode is 90 °, the present disclosure also includes an embodiment in which the apex angle exceeds 45 °.
The dielectric is not particularly limited as long as it is a material having high electrical insulation. For example, resins such as polyimide, polyester, fluororesin, silicone resin, acrylic resin, and phenol resin, glass, ceramics, and composite materials obtained by mixing them with a resin or the like can be used. Among these, it is preferable that the dielectric is ceramics or glass because it is difficult for the fire to spread even if a current leaks.

<Plasma actuator>
The plasma actuator is not particularly limited as long as it is capable of generating an induced flow containing ozone by providing a first electrode and a second electrode with a dielectric interposed therebetween and applying a voltage between the two electrodes.
In the plasma actuator, the shorter the shortest distance between the first electrode and the second electrode, the easier it is for plasma to be generated. Therefore, the film thickness of the dielectric is preferably as long as it is within the range where electrical dielectric breakdown does not occur, and can be preferably 10 μm to 1000 μm, preferably 10 μm to 200 μm. The shortest distance between the first electrode and the second electrode is preferably 200 μm or less.
FIG. 3 is an explanatory diagram of the overlap between the first electrode 203 and the second electrode 205 of the plasma actuator which is an ozone generator. It is sectional drawing of a plasma actuator.
When viewed from the upper side of the cross-sectional view, the first electrode 203 and the second electrode 205 arranged diagonally opposite each other have the edge of the first electrode on the forming portion of the second electrode with the dielectric interposed therebetween. It may exist. That is, the first electrode and the second electrode may be provided so as to overlap each other with the dielectric interposed therebetween. In this case, it is preferable to prevent dielectric breakdown when a voltage is applied at a portion where the first electrode and the second electrode overlap each other with the dielectric sandwiched between them.
When the first electrode and the second electrode are separated from each other when viewed from the upper part of the cross-sectional view, it is preferable to increase the voltage in order to compensate for the weakening of the electric field due to the distance between the electrodes. The overlap between the edge portion of the first electrode and the edge portion of the second electrode is more preferably -100 μm to +1000 μm when viewed from the upper part of the cross-sectional view, where the overlapping length is positive.
The thickness of the electrodes is not particularly limited for both the first electrode and the second electrode, but can be 10 μm to 1000 μm. When it is 10 μm or more, the resistance becomes low and plasma is easily generated. When it is 1000 μm or less, electric field concentration is likely to occur, so plasma is likely to be generated.
The width of the electrodes is not particularly limited for both the first electrode and the second electrode, but can be 1000 μm or more.
Further, when the edge of the second electrode is exposed, plasma is also generated from the edge of the second electrode, and an induced flow in the direction opposite to the induced flow 105 derived from the first electrode is generated. obtain. In the active oxygen supply device according to this embodiment, it is preferable to keep the ozone concentration in the internal space of the active oxygen supply device other than the surface region of the object to be treated as low as possible. Further, it is preferable not to generate a gas flow in the container that disturbs the flow of the induced flow 105. Therefore, it is preferable not to generate an induced flow derived from the second electrode. Therefore, as shown in FIGS. 2 and 3, the second electrode 205 is covered with a dielectric such as the dielectric substrate 206 or embedded in the dielectric 201 to prevent the generation of plasma from the edge of the second electrode. It is preferable to do so.

The induced flow 105 containing high-concentration ozone is jet-like flow direction by surface plasma from the edge 204 of the first electrode 203 to the exposed portion 21-1 of the first surface of the dielectric 201, that is, the first. Flows from the edge 204 of the electrode 203 along the exposed portion 21-1 on the first surface of the dielectric. This induced flow is a flow of a gas containing high-concentration ozone having a velocity of about several m / s to several tens of m / s.
The voltage applied between the first electrode 203 and the second electrode 205 of the plasma actuator is not particularly limited as long as it can generate plasma in the plasma actuator. Further, it may be a DC voltage or an AC voltage, but an AC voltage is preferable. It is also a preferred embodiment that the voltage is a pulse voltage.
Further, the amplitude and frequency of the voltage can be appropriately set in order to adjust the flow velocity of the induced flow and the ozone concentration in the induced flow. In this case, the effective active oxygen concentration according to the purpose of the treatment or the ozone concentration required to generate the effective active oxygen amount is generated in the induced flow, and the generated active oxygen is effective according to the purpose of the treatment. It may be appropriately selected from the viewpoint of supplying to the surface region of the object to be treated while maintaining the active oxygen concentration or the effective active oxygen amount.
For example, the amplitude of the voltage can be 1 kV to 100 kV. Furthermore, the frequency of the voltage can be preferably 1 kHz or higher, more preferably 10 kHz to 100 kHz.
When the voltage is an AC voltage, the waveform of the AC voltage is not particularly limited, and a sine wave, a rectangular wave, a triangular wave, or the like can be adopted, but a rectangular wave is preferable from the viewpoint of the speed of voltage rise. ..
The duty ratio of the voltage can be appropriately selected, but it is preferable that the voltage rises quickly. Preferably, the voltage is applied so that the rise of the voltage reaching the peak from the bottom of the amplitude of the wavelength is 400,000 V / sec or more.
The value (voltage / film thickness) obtained by dividing the amplitude of the voltage applied between the first electrode 203 and the second electrode 205 by the film thickness of the dielectric 201 is preferably 10 kV / mm or more. ..

<Ultraviolet light source and ultraviolet rays>
The ultraviolet light source is not particularly limited as long as it can irradiate ultraviolet rays that can excite ozone and generate active oxygen. Further, the ultraviolet light source is not particularly limited as long as it has the wavelength of ultraviolet rays and the illuminance thereof necessary for exciting ozone and obtaining an effective active oxygen concentration or an effective active oxygen amount according to the purpose of treatment.
For example, since the peak value of the light absorption spectrum of ozone is 260 nm, the peak wavelength of the ultraviolet rays is preferably 220 nm to 310 nm, more preferably 253 nm to 285 nm, and more preferably 253 nm to 266 nm. More preferred.
As a specific ultraviolet light source, a low-pressure mercury lamp in which mercury is sealed together with an inert gas such as argon or neon in quartz glass, a cold cathode fluorescent lamp (UV-CCL), an ultraviolet LED, or the like can be used. The wavelength of the low-pressure mercury lamp or the cold-cathode tube ultraviolet lamp may be selected from 254 nm and the like. On the other hand, the wavelength of the ultraviolet LED may be selected from 265 nm, 275 nm, 280 nm and the like from the viewpoint of output performance.

<Arrangement of plasma generator, ultraviolet light source and object to be processed>
In the active oxygen supply device 101, the position of the plasma generator 103 that generates the induced flow containing ozone is such that the induced flow 105 is the effective active oxygen concentration according to the purpose of the treatment due to the ultraviolet rays emitted from the ultraviolet light source 102. It is not particularly limited as long as it is arranged so as to flow out of the housing through the opening and be supplied to the surface of the object to be treated while the amount of effective active oxygen is maintained.
For example, the plasma generator and the ultraviolet light source may be arranged so that the induced flow 105 containing active oxygen generated by ultraviolet rays is supplied to the surface of the object to be processed at the shortest distance.
Further, for example, the treated surface 104-1 of the object to be treated is included on the extension line in the direction from the edge of the first electrode of the plasma actuator to the exposed portion 21-1 of the first surface of the dielectric. It is good to place it.
Further, when the opening of the active oxygen supply device is directed vertically downward, an extension line 201-in the direction from the edge of the first electrode of the plasma actuator to the exposed portion 21-1 of the first surface of the dielectric. The narrow angle θ (hereinafter, also referred to as plasma actuator incident angle, PA incident angle; see FIG. 4) formed by 1-1 and the horizontal plane (plane perpendicular to the vertical direction) is effective active oxygen or effective active oxygen according to the purpose of treatment. The angle is not particularly limited as long as it can actively supply the induced flow to the surface region of the object to be treated while maintaining the effective amount of active oxygen, or the angle can be treated with active oxygen, but it is 0 ° to 90 °. It is preferably 30 ° to 70 °, and more preferably 30 ° to 70 °.
By arranging the plasma generator and the ultraviolet light source as described above, an induced flow containing active oxygen having a certain flow velocity can be locally supplied to a region near the surface of the object to be treated or active oxygen. Can be processed by.

The ultraviolet light source irradiates the induced flow with ultraviolet rays, generates active oxygen in the induced flow, and maintains the effective active oxygen concentration or the effective active oxygen amount according to the purpose of the treatment on the surface of the object to be treated. As long as it is arranged so that it can be processed, there is no particular limitation other than that.
As described above, the induced flow containing ozone is actively supplied to the region near the surface of the object to be treated. Further, by irradiating the induced flow with ultraviolet rays, active oxygen can be generated in the induced flow. Therefore, when the induced flow is irradiated with ultraviolet rays, ozone is excited and the induced flow in a state where active oxygen is generated can be actively supplied to the surface of the object to be treated, and the object to be processed The active oxygen concentration or the amount of active oxygen on the surface of the surface can be significantly increased.
The relative position between the ultraviolet light source and the plasma generator is such that active oxygen is generated in the induced flow, and the effective active oxygen concentration or the effective active oxygen amount according to the purpose of the treatment is maintained on the surface of the object to be treated. As long as each is arranged so that processing can be performed, there is no particular limitation other than that.
Further, since the distance between the ultraviolet light source and the plasma generator also changes depending on the purpose of processing, it cannot be unconditionally specified, but for example, it is preferably 10 mm or less, and more preferably 4 mm or less. However, it is not necessary to place the plasma generator within about 10 mm from the ultraviolet light source, and the active oxygen in the induced flow should be the effective concentration according to the purpose of the treatment in relation to the illuminance and wavelength of the ultraviolet rays described later. If possible, the distance between the ultraviolet light source and the plasma generator is not particularly limited.
It is also a preferred embodiment to provide a moving means on at least one of the ultraviolet light source and the plasma generator so that at least one of the ultraviolet light source and the plasma generator can be moved so that the illuminance of the ultraviolet rays becomes uniform.

The relative position between the active oxygen supply device and the object to be treated is such that active oxygen is generated in the induced flow and the induced flow is treated with the effective active oxygen concentration or the amount of effective active oxygen maintained according to the purpose of the treatment. At least one of each may be arranged so that the surface of the object is exposed.
Further, the ultraviolet light source may be arranged at a position where the ultraviolet rays can irradiate the surface of the object to be treated, or may be arranged at a position where the ultraviolet rays cannot irradiate the surface of the object to be processed. Even when the surface of the object to be treated cannot be irradiated with ultraviolet rays from an ultraviolet light source, the surface to be treated is exposed to the active oxygen in the induced flow in the treatment device using active oxygen according to this embodiment. It is possible to process. Further, in the sterilization treatment with ultraviolet rays, only the surface irradiated with ultraviolet rays is sterilized. However, in the sterilization treatment by the active oxygen supply device according to the present disclosure, the bacteria existing at the position where the active oxygen can reach can be sterilized. Therefore, for example, even bacteria existing between fibers, which are difficult to sterilize by irradiation with ultraviolet rays from the outside, can be sterilized.

On the other hand, when the ultraviolet rays from the ultraviolet light source are arranged so as to be able to irradiate the surface of the object to be treated placed outside the housing through the opening, the undecomposed ozone existing in the induced flow is covered. It can decompose in situ on the treated surface and generate active oxygen on the treated surface. As a result, the degree of processing and the efficiency of processing can be further improved.
In this case, the illuminance of ultraviolet rays on the surface of the object to be treated or the illuminance of ultraviolet rays at the openings is not particularly limited, but for example, ozone contained in the induced flow is decomposed and induced also on the surface or openings of the object to be treated. It is preferable to set the illuminance of ultraviolet rays that can generate active oxygen in the flow and generate an effective active oxygen concentration or an effective active oxygen amount according to the purpose of the treatment. Specifically, for example, as a specific example of the illuminance of ultraviolet rays on the surface of the object to be treated or the illuminance of ultraviolet rays at an opening, it is preferably 40 μW / cm ² or more, and more preferably 100 μW / cm ² or more. , 400 μW / cm ² or more is more preferable, and 1000 μW / cm ² or more is particularly preferable. The upper limit of the illuminance is not particularly limited, but can be, for example, 10000 μW / cm ² or less.

Further, since the distance between the ultraviolet light source and the surface of the object to be treated also changes depending on the purpose of the treatment, it cannot be unconditionally defined, but for example, it is preferably 10 mm or less, and more preferably 4 mm or less. However, it is not necessary to place the object to be treated so that the surface to be treated is within about 10 mm from the ultraviolet light source, and the active oxygen in the induced flow is treated according to the purpose of the treatment in relation to the illuminance of the ultraviolet rays. The distance between the ultraviolet light source and the object to be treated is not particularly limited as long as the effective concentration can be obtained.
Further, the amount of ozone generated per unit time in the plasma actuator in a state where the induced flow is not irradiated with ultraviolet rays is preferably, for example, 15 μg / min or more. More preferably, it is 30 μg / min or more. The upper limit of the ozone generation amount is not particularly limited, but is, for example, 1000 μg / min or less.
The flow velocity of the induced flow is, for example, a speed at which the generated active oxygen can be actively supplied to the surface region of the object to be treated while maintaining the effective active oxygen concentration or the effective active oxygen amount according to the purpose of the treatment. All you need is. For example, as described above, it is about 0.01 m / s to 100 m / s.
As described above, the concentration of ozone in the induced flow generated from the plasma actuator and the flow velocity of the induced flow can be controlled by the thickness and material of the electrode and the dielectric, the type, amplitude, frequency and the like of the applied voltage.

<Case and opening>
The active oxygen supply device of the present disclosure includes a housing 107 having at least one opening 106, an ultraviolet light source 102 arranged in the housing, and a plasma generator 103.
The opening is not particularly limited as long as the induced flow 105 generated from the plasma generator 103 flows out of the housing 107. The size of the opening, the position of the opening, and the relative position between the opening and the object to be treated were determined by, for example, maintaining the generated active oxygen at an effective active oxygen concentration or an effective active oxygen amount according to the purpose of treatment. It can be appropriately selected so that it can be actively supplied to the surface area of the object to be treated in the state.

The active oxygen supply device of the present disclosure can be used not only for sterilization of the object to be treated, but also for all applications implemented by supplying active oxygen to the object to be treated. For example, the active oxygen supply device of the present disclosure can also be used for deodorizing the object to be treated, bleaching the object to be treated, hydrophilizing surface treatment of the object to be treated, and the like.
Further, the treatment device using active oxygen of the present disclosure not only performs a treatment for sterilizing the material to be treated, but also, for example, a treatment for deodorizing the material to be treated, a treatment for bleaching the material to be treated, and a treatment for making the material to be treated hydrophilic. It can also be used for surface treatment to be sterilized.

In the present disclosure, the "effective active oxygen concentration or effective active oxygen amount" is the active oxygen concentration or the amount of active oxygen for achieving the purpose for the object to be treated, for example, sterilization, deodorization, bleaching or hydrophilization. The electrodes constituting the plasma actuator, the thickness of the dielectric, the material, the type of applied voltage, the amplitude and frequency, the illuminance and irradiation time of ultraviolet rays, the PA incident angle, and the like can be appropriately adjusted according to the purpose.

Hereinafter, the present disclosure will be described in more detail with reference to Examples and Comparative Examples, but the embodiments of the present disclosure are not limited thereto.

<Example 1>
1. 1. Fabrication of active oxygen supply device Aluminum with a length of 2.5 mm, a width of 15 mm, and a thickness of 100 μm on the first surface of a glass plate (length 5 mm, width (page depth direction in FIG. 1) 18 mm, thickness 150 μm) as a dielectric. The foil was attached with adhesive tape to form the first electrode. Further, an aluminum foil having a length of 3 mm, a width of 15 mm, and a thickness of 100 μm is also attached to the second surface of the glass plate with an adhesive tape so as to be diagonally opposite to the aluminum foil attached to the first surface. Electrode was formed. Further, the second surface including the second electrode was covered with polyimide tape. In this way, a plasma actuator is manufactured in which the first electrode and the second electrode are provided so as to overlap each other over a width of 0.5 mm with a dielectric (glass plate) interposed therebetween. Two of these plasma actuators were prepared.

Next, as the housing 107 of the active oxygen supply device 101, a case made of ABS resin having a height of 25 mm, a width of 20 mm, a length of 170 mm, and a thickness of 2 mm and having a substantially trapezoidal cross-sectional shape shown in FIG. 1 is prepared. bottom. The case had an opening 106 having a width of 7 mm and a length of 166 mm on one side thereof. Next, the two plasma actuators produced earlier were fixed to the inner wall of the hypotenuse portion of the housing 107. Specifically, the plasma actuator 103 is formed by the intersection of the extension line 201-1-1 in the direction along the exposed portion 21-1 of the first surface of the dielectric 201 and the treated surface 104-1 of the object to be treated. The angle θ (equivalent to the PA incident angle described above) was 45 °.
Further, an ultraviolet lamp 102 (cold-cathode tube ultraviolet lamp, trade name: UW / 9F89 / 9, manufactured by Stanley Electric Co., Ltd., cylindrical shape with a diameter of 9 mm, peak wavelength = 254 nm) was arranged in the housing. The distance between the ultraviolet lamp 102 and the exposed portion 21-1 on the first surface of the dielectric 201 of the plasma actuator (reference numeral 403 in FIG. 4) is 2 mm, and the flat plate is brought into contact with the opening 106 of the housing 107. At that time, the distance between the ultraviolet light source and the surface of the flat plate on the side facing the ultraviolet light source (reference numeral 401 in FIG. 4) was 3 mm. In this way, the active hydrogen supply device (treatment device using active oxygen) according to this example was produced.

An illuminance meter (trade name: spectral irradiance meter USR-45D, manufactured by Ushio Denki Co., Ltd.) was placed at the position of the opening 106 which is the supply port of active oxygen in the active oxygen supply device 101, and the illuminance of ultraviolet rays was measured. From the integrated value of the spectrum, it was 1370 μW / cm ² . At this time, the power was not turned on to the plasma actuator so as not to be affected by the shielding of ultraviolet rays by ozone generated from the plasma actuator. Since the object to be treated is placed, for example, at the position of the opening 106, the illuminance of ultraviolet rays measured under such conditions was regarded as the illuminance of ultraviolet rays on the surface of the object to be treated.

Subsequently, in order to calculate the amount of ozone generated from the plasma actuator 103, the active oxygen supply device 101 was placed in a closed container (not shown) having a volume of 1 liter. The closed container is provided with a hole that can be sealed with a rubber stopper so that the gas inside can be sucked from the hole with a syringe. Then, 100 ml of gas in the closed container was sampled 1 minute after applying a voltage having a sine waveform having an amplitude of 2.4 kV and a frequency of 80 kHz to the plasma actuator 103. The collected gas was sucked into an ozone detector tube (trade name: 182SB, manufactured by Komei Rikagaku Kogyo Co., Ltd.), and the measured ozone concentration (PPM) contained in the induced flow from the plasma actuator 103 was measured. Using the measured ozone concentration value, the amount of ozone generated per unit time was calculated by the following formula.

As a result, the amount of ozone generated per unit time was 39 μg / min. At this time, the power was not turned on to the ultraviolet light source so as not to be affected by the decomposition of ozone by the ultraviolet rays emitted from the ultraviolet light source.
Finally, the amount of ozone generated when both the plasma actuator 103 and the ultraviolet lamp 102 were in operation was measured. The operating condition of the plasma actuator 103 is a condition for generating ozone of 39 μg / min when only the plasma actuator 103 is operated. Further, the operating condition of the ultraviolet lamp 102 is a condition that the illuminance becomes 1370 μW / cm ² when only the ultraviolet lamp 102 is operated. As a result, the amount of ozone generated when both the plasma actuator 103 and the ultraviolet lamp 102 were operating was 8 μg / min. It is considered that 31 μg / min, which is a decrease from 39 μg / min, is the amount of ozone converted into active oxygen.

2-1. Treatment (hydrophilization) test A polypropylene resin test piece (manufactured by TP Giken Co., Ltd.) cut into a square with a length of 15 mm and a width of 15 mm was prepared as an object to be treated 104. The object to be treated was placed in the opening 106 of the active oxygen supply device 101 produced in 1 above so that the distance 405 in FIG. 4 was 3 mm. Next, a voltage having a sine waveform having an amplitude of 2.4 kV and a frequency of 80 kHz was applied to the plasma actuator, and ultraviolet rays were irradiated for 1 hour to perform surface treatment of the object to be treated (treatment time: 1 hour). Then, the contact angle of the surface treated with the induced flow of the polypropylene resin plate with respect to water was measured and compared with the contact angle before the treatment. The contact angle was measured at 23 ° C. and 50% RH using an automatic contact angle meter (trade name: DMo-602, manufactured by Kyowa Surface Chemical Co., Ltd.) as a measuring instrument, and 0.5 μL of water was used as the droplet. The angle after 500 msec of dropping was measured, and the value obtained by averaging 5 points was adopted. The contact angle of the surface of the polypropylene resin plate before treatment was 102 °.

2-2. Treatment (sterilization) test (1) Preparation of samples for sterilization test Three samples for use in the verification test of sterilization performance were prepared by the following method.
25 g / g of stamp medium (trade name: Petan Check 25 PT1025 Eiken Kasei Co., Ltd.) on the door knob that has not been cleaned with water, alcohol, etc. for a week, where an unspecified number of people come and go. After pressing at a pressure of cm ² for 10 seconds, the stamp medium was placed in an environment with a temperature of 37 ° C. for 12 hours. The colonies grown on the stamp medium were collected using a sterile cotton swab, and a bacterial solution dispersed in distilled water was prepared. 0.1 ml of the diluted bacterial solution obtained by diluting this bacterial solution 10-fold with distilled water was smeared on a new stamp medium (Petancheck 25 PT1025, manufactured by Eiken Kasei Co., Ltd.) and left in an environment at a temperature of 37 ° C. for 12 hours. As a result, the growth of bacteria of 200 CFU / ml to 300 CFU / ml was observed. Therefore, 0.1 ml of the diluted bacterial solution was smeared on the entire surface of a glass plate (length 15 mm, width 15 mm, thickness 2 mm) whose surface was cleaned with alcohol having a concentration of 70%. Then, it was left in an environment of 37 ° C. for 1 hour to remove water. In this way, a total of three samples for sterilization test were prepared.

(2) Sterilization test An active oxygen supply device 101 was placed on the surface to be treated of each sample so that the distance 405 in FIG. 4 was 3 mm. Further, the center position in the width direction (left-right direction in FIG. 4) of the sample 104 coincides with the center position in the width direction of the opening 106, and the center position in the depth direction (paper surface depth direction in FIG. 4) of the sample 104. And the center position of the opening 106 in the depth direction. Next, a voltage having a sine waveform having an amplitude of 2.4 kV and a frequency of 80 kHz is applied to the plasma actuator 103, and the illuminance on the surface of the glass plate 201 of the plasma actuator 103 facing the ultraviolet lamp is 1370 μW / cm ² . The UV lamp was turned on, the induced flow and the surface to be treated were irradiated with ultraviolet rays for 10 seconds, and the induced flow containing active oxygen was discharged from the opening 106 to treat the surface to be treated 104-1 (treatment time 10). Seconds). Next, stamp medium (trade name: Petancheck 25 PT1025) on the surface to be treated of the sample.
Eiken Kasei Co., Ltd.) was pressed at a pressure of 25 g / cm ² for 10 seconds, and then the stamp medium was placed in an environment at a temperature of 37 ° C. for 12 hours. Then, the number of surviving bacteria was calculated from the number of colonies that grew on the stamp medium. The number of colonies in the sterilization test according to this example was obtained by multiplying the average number of surviving bacteria obtained from each sample by 10. From the number of colonies obtained, the sterilization performance was evaluated according to the following criteria (Ten Cate determination display method).
-: No growth ±: Number of colonies <10 +: Number of colonies 10 to 29 ++: Number of colonies 30 to 100 +++: Number of colonies> 100 +++: Number of colonies innumerable

2-3. Treatment (bleaching) test (1) Preparation of sample for bleaching test Chili sauce (trade name: Pepper sauce, manufactured by Tabasco) is filtered through a long fiber non-woven fabric (trade name: Bencot M-3II, manufactured by Asahi Kasei) to remove solid content. Removed. A paper wiper (trade name: Kimwipe S-200, manufactured by Nippon Paper Crecia) was immersed in the obtained liquid for 10 minutes. Then, the paper wiper was taken out and washed with water. Washing with water was repeated until the washing liquid was not visually colored. Then it was dried. Next, three samples having a length of 15 mm and a width of 15 mm were cut out from the paper wiper dyed in red by the chili sauce.

(2) Bleaching test An active oxygen supply device 101 was placed on the surface to be treated of the obtained bleaching test sample so that the distance 405 in FIG. 4 was 3 mm. The center position in the width direction of the sample 104 coincided with the center position in the width direction of the opening 106, and also coincided with the center position in the depth direction of the sample 104 and the center position in the longitudinal direction of the opening 106. Next, a voltage having a sine waveform having an amplitude of 2.4 kV and a frequency of 80 kHz is applied to the plasma actuator 103, and the illuminance on the surface of the glass plate 201 of the plasma actuator 103 facing the ultraviolet lamp is 1370 μW / cm ² . The ultraviolet lamp was turned on, and the induced flow and the surface to be treated were irradiated with ultraviolet rays for 10 minutes to supply an induced flow containing active oxygen to a part of the surface to be treated 104-1 (treatment time: 10 minutes). Next, the active oxygen supply device 101 was removed from the surface to be treated, and the degree of decolorization was visually observed in comparison with the sample before treatment, and the evaluation was made according to the following criteria.
A: It was completely bleached.
B: A little red color of chili sauce remained.
C: Some red color of chili sauce remained.
D: There was no difference from the color of the part to which active oxygen was not supplied.

2-4. Treatment (deodorant) test (1) Preparation of deodorant test sample A paper wiper (Kimwipe S-200, manufactured by Nippon Paper Crecia) was immersed in a fabric mist (trade name: fabric mist linen, manufactured by Savon) for 10 minutes. After that, it was taken out and naturally dried for 6 hours. Next, the paper wiper was cut into a size of 10 mm in length and 10 mm in width to obtain a sample for deodorization test.

(2) Deodorization test An active oxygen supply device 101 was placed on the surface to be treated of each sample so that the distance 405 in FIG. 4 was 3 mm. The center position in the width direction of the sample coincided with the center position in the width direction of the opening, and also coincided with the center position in the depth direction of the sample and the center position in the longitudinal direction of the opening. Next, a voltage having a sine waveform with an amplitude of 2.4 kV and a frequency of 80 kHz is applied to the plasma actuator, and the illuminance on the surface of the glass plate 201 of the plasma actuator 103 facing the ultraviolet lamp is 1370 μW / cm ² . The ultraviolet lamp was turned on, and the induced flow and the surface to be treated were irradiated with ultraviolet rays for 10 seconds to supply an induced flow containing active oxygen to a part of the surface to be treated (treatment time: 10 seconds). Then, the active oxygen supply device was removed from the surface to be treated. Then, how much the odor of the treated sample remained in comparison with the sample not treated with active oxygen was evaluated by the following intensity criteria. The evaluation was performed on 5 subjects, and the intensity criteria selected by at least 3 subjects were adopted.
A: Odorless.
B: An odor that can finally be detected (detection threshold).
C: A weak odor (cognitive threshold) that can be recognized as a fabric mist odor.
D: No difference from the untreated sample.

<Example 2>
An active oxygen supply device was produced and evaluated in the same manner as in Example 1 except that the voltage of the ultraviolet lamp 102 of Example 1 was lowered from 24 V to 12 V and the illuminance was lowered.

<Examples 3 to 6>
An active oxygen supply device was produced and evaluated in the same manner as in Example 1 except that the wavelength of the ultraviolet light source and the thickness and material of the dielectric of the plasma actuator were changed as shown in Table 1.
In Example 6, an ultraviolet LED (peak wavelength 280 nm) was used as an ultraviolet light source.

<Comparative Examples 1 to 3>
Comparative Examples 1 to 3 had the same conditions as those of Example 1 except that they had the following configurations.
Comparative Example 1: No voltage was applied to the plasma actuator, and no ultraviolet light was applied.
Comparative Example 2: A voltage was applied to the plasma actuator and no ultraviolet light was applied.
Comparative Example 3: No voltage was applied to the plasma actuator, and ultraviolet rays were irradiated.

<Example 7>
1. 1. Fabrication of processing device using active oxygen and evaluation of characteristics First, the housing 601 of the active oxygen supply device 600 shown in FIG. 6 was prepared. FIG. 5 is a plan view of the active oxygen supply device according to FIG. 6 as viewed from the side of the surface of the housing 601 having the opening 605. The size of the housing was 20 mm in height, 150 mm in depth, and 20 mm in width when the opening 605 was placed so as to face vertically downward. The opening 605 had a width of 7 mm and a length of 15 mm. As shown in FIG. 5, the opening 605 is provided so that the longitudinal direction thereof coincides with the depth direction of the housing.
Moreover, the plasma actuator 103 was manufactured in the same manner as in Example 1. Next, the plasma actuator 103 was fixed to the inner wall of the housing 601 as shown in FIG. Specifically, one end of the first electrode 203 of the plasma actuator 103 is at a position horizontally aligned with the center of the ultraviolet lamp 102, and the induced flow 105 from the plasma actuator 103 is from the opening 605. Fixed to flow out. Here, the distance between the surface of the plasma actuator 103 facing the ultraviolet light source and the ultraviolet lamp 102 (reference numeral 607 in FIG. 7) is 2 mm, and the lower end of the plasma actuator 103 to the lower end of the opening 605 (outside the housing). ) (Reference numeral 609 in FIG. 7) was set to 1 mm. As the ultraviolet lamp 102, a cold cathode fluorescent lamp (trade name: UW / 9F89 / 9, manufactured by Stanley Electric Co., Ltd., peak wavelength = 254 nm) was used as in Example 1.
Regarding the active oxygen supply device 600 thus obtained, an illuminance meter (trade name: spectroscopic radiation illuminance meter USR-45D, manufactured by Ushio Denki Co., Ltd.) is placed on the surface of the glass plate 201 of the plasma actuator 103 facing the ultraviolet lamp. The illuminance of ultraviolet rays was measured. From the integrated value of the spectrum, it was 1370 μW / cm ² . Further, the illuminance of the ultraviolet rays when the illuminometer was placed in contact with the opening 605 was 0.3 μW / cm ² . From this, it was confirmed that there was virtually no leakage of ultraviolet rays from the opening.

Next, in order not to be affected by the decomposition of ozone by ultraviolet rays, a voltage having a sine waveform with an amplitude of 2.4 kV and a frequency of 80 kHz is applied between both electrodes of the plasma actuator 103 without turning on the power of the ultraviolet lamp. After 5 minutes, 50 ml of induced flow flowing out of the opening was sampled. The collected gas was sucked into an ozone detector tube (trade name: 182SB, manufactured by Komei Rikagaku Kogyo Co., Ltd.), and the ozone concentration contained in the induced flow from the plasma actuator was measured and found to be 70 ppm (reading value × 2).
Next, a voltage having a sine waveform with an amplitude of 2.4 kV and a frequency of 80 kHz is applied between both electrodes of the plasma actuator, and the ultraviolet lamp is illuminated on the surface of the glass plate 201 of the plasma actuator 103 facing the ultraviolet lamp. The ultraviolet lamp was turned on so that the voltage was 1370 μW / cm ² . Then, the ozone concentration in the induced flow flowing out from the opening at this time was measured in the same manner as described above. As a result, it was 18 ppm. From these results, it is considered that this induced flow contains active oxygen in which 52 ppm of ozone is decomposed by ultraviolet rays.

2. 2. Treatment test Using the active oxygen supply device produced in 1 above, a treatment test was performed in the same manner as the treatment (surface modification, sterilization, deodorization, bleaching) test described in Example 1.

2-1. Surface modification (hydrophilization treatment) test On the surface to be treated of each sample, the active oxygen supply device according to this embodiment is installed, and the distance between the outer surface having the opening of the housing and the surface to be treated (in FIG. 7). The reference numeral 611) was set to be 2 mm. At this time, the center position in the width direction of the sample (horizontal direction in FIG. 7) coincides with the center position in the width direction of the opening, and the center position and the opening in the depth direction of the sample (paper depth direction in FIG. 7). It was also matched with the longitudinal center position of. Other than that, the hydrophilization treatment test was performed in the same manner as in the hydrophilization treatment test described in Example 1.

2-2. Sterilization test On the surface to be treated of each sample, the active oxygen supply device according to this embodiment has a distance (reference numeral 611 in FIG. 7) of 2 mm between the outer surface having the opening of the housing and the surface to be treated. It was installed so as to be. At this time, the center position in the width direction of the sample (horizontal direction in FIG. 7) coincides with the center position in the width direction of the opening, and the center position and the opening in the depth direction of the sample (paper depth direction in FIG. 7). It was also matched with the longitudinal center position of. Further, the irradiation time of ultraviolet rays for the induced flow was set to 30 seconds (treatment time: 30 seconds). Other than these, the sterilization test was carried out in the same manner as the sterilization test described in Example 1.

2-3. Bleaching test On each sample, an active oxygen supply device was installed so that the distance between the outer surface having the opening of the housing and the surface to be treated (reference numeral 611 in FIG. 7) was 2 mm, and the bleaching test was applied to the induced flow. The bleaching test was carried out in the same manner as the bleaching test described in Example 1 except that the irradiation time of ultraviolet rays was 20 minutes (treatment time was 20 minutes).

2-4. Deodorization test An active oxygen supply device was installed on the surface to be treated of each sample so that the distance between the lower end of the opening and the surface to be treated was 2 mm. At this time, the center position in the width direction of the sample (horizontal direction in FIG. 7) coincides with the center position in the width direction of the opening, and the center position and the opening in the depth direction of the sample (paper depth direction in FIG. 7). It was also matched with the longitudinal center position of. Further, the irradiation time of ultraviolet rays for the induced flow was set to 20 seconds (treatment time 20 seconds). Other than these, the deodorization test was carried out in the same manner as the deodorization test described in Example 1.

表中、ＰＡはプラズマアクチュエータを表し、ＵＶは紫外線を表す。また、オゾン濃度は、紫外線光源に電源を入れなかった場合のオゾン濃度を示す。

In the table, PA represents a plasma actuator and UV represents ultraviolet rays. Further, the ozone concentration indicates the ozone concentration when the power is not turned on to the ultraviolet light source.

Device conditions of the active oxygen supply device of Examples 1 to 7 and Comparative Examples 1 to 3, ozone concentration when only the plasma actuator is operated, ultraviolet illuminance when only the UV cold cathode fluorescent lamp is operated, reduction of contact angle, Table 1 shows the evaluation results of each treatment of sterilization / deodorization / bleaching.

The decrease in the contact angle did not occur with ultraviolet rays as in Comparative Example 3. Further, when ozone is generated as in Comparative Example 2, the contact angle is lowered. Furthermore, when both ozone generation and ultraviolet irradiation were performed, the contact angle was further lowered due to the high reactivity of active oxygen.
In Comparative Example 1, since neither the plasma actuator nor the active oxygen was in operation, there was no effect of sterilization, deodorization, and bleaching by ultraviolet rays, ozone, and active oxygen. In Comparative Example 2, some effects of sterilization, deodorization, and bleaching by ozone were observed, but they were not as good as those of Examples 1 to 7. In Comparative Example 3, some effects of sterilization by ultraviolet rays were observed, but no effects of deodorization and bleaching were observed.

<Example 8>
Using the active oxygen supply device prepared in Example 1, a sterilization test of Escherichia coli was carried out according to the following procedure. All the instruments used in this sterilization test were those subjected to high-pressure steam sterilization using an autoclave. In addition, this sterilization test was conducted in a clean bench.
First, in an Erlenmeyer flask containing LB medium (2 g of tryptone, 1 g of yeast extract, 1 g of sodium chloride and 200 ml of distilled water), Escherichia coli (trade name "KWIK-STIK (Escherichia coli) ATCC8739), (Manufactured by Microbiologicals) was added and cultured at a temperature of 37 ° C. for 48 hours at 80 rpm. The bacterial solution of Escherichia coli after culturing was ^9.2 × 109 (CFU / ml).
0.010 ml of this cultured bacterial solution is dropped onto a slide glass (Matsunami glass, model number: S2441) having a length of 3 cm, a width of 1 cm, and a thickness of 1 mm using a micropipette, and the bacterial solution is slid with the tip of the micropipette. Apply to the entire surface of one side of the glass and sample No. 8-1 was produced. Further, in the same manner, the sample No. 8-2 to 8-3 were prepared.

Next, the sample No. 8-1 was immersed in a test tube containing 10 ml of a buffer solution (trade name "Gibco PBS", Thermo Fisher Scientific) for 1 hour. In order to prevent the bacterial solution on the slide glass from drying, the time from the dropping of the bacterial solution onto the slide glass to the immersion in the buffer solution was set to 60 seconds.
Next, the sample No. Prepare a diluted solution (hereinafter, "1/10 diluted solution") by putting 1 ml of the buffer solution (hereinafter, also referred to as "1/1 solution") after immersing 8-1 in a test tube containing 9 ml of the buffer solution. bottom. A 1/100 diluted solution, a 1/1000 diluted solution, and a 1/10000 diluted solution were prepared in the same manner except that the dilution ratio with the buffer solution was changed.
Next, 0.050 ml was collected from the 1/1 solution and smeared on a stamp medium (Petancheck 25 PT1025 manufactured by Eiken Kasei Co., Ltd.). By repeating this operation, two stamp media smeared with 1/1 liquid were prepared. The two stamp media were placed in a constant temperature bath (trade name: IS600; manufactured by Yamato Scientific Co., Ltd.) and cultured at a temperature of 37 ° C. for 24 hours. The number of colonies generated on the two stamp media was counted, and the average value was calculated.
For the 1/10 diluted solution, the 1/100 diluted solution, the 1/1000 diluted solution, and the 1/10000 diluted solution, two smeared stamp media were prepared for each diluted solution and cultured. Then, the number of colonies generated for each stamp medium related to each diluted solution was counted, and the average value was calculated. The results are shown in Table 2.

From the results shown in Table 2 above, the number of colonies when the 1/10000 diluted solution was cultured was 21, and therefore, the sample No. It was found that the number of bacteria present in 0.050 ml of the 1/1 liquid according to 8-1 was 21 × 10 ⁴ = 210000 (CFU).

Next, the sample No. The following operations were performed for 8-2 to 8-3.
A recess of 3.5 cm in length, 1.5 cm in width and 2 mm in depth is provided in the center of a plastic flat plate having a length of 30 cm, a width of 30 cm and a thickness of 5 mm. The slide glass was installed so that the opposite surface was in contact with the bottom surface of the recess. Then, on the upper surface of the plastic plate, an active oxygen supply device is provided so that the center in the longitudinal direction of the opening coincides with the center in the longitudinal direction of the recess and the center in the width direction of the recess is in the lateral direction of the recess. I placed it so that it coincided with the center of. Since the depth of the recess is 2 mm and the thickness of the slide glass is 1 mm, the bacterial solution adhering surface of each sample did not come into direct contact with the opening of the active oxygen supply device.
Next, the active oxygen supply device was operated, and the bacterial solution-coated surface of the slide glass was treated with an induced flow containing active oxygen. The processing time is the sample No. 8-2 is 2 seconds, sample No. 8-3 was set to 10 seconds. Further, in the treatment process using the active oxygen supply device, the time from the dropping of the bacterial solution onto the slide glass to the immersion in the buffer solution was set to 60 seconds so that the bacterial solution on the slide glass would not dry out.

Finished sample No. Each of 8-2 to 8-3 was immersed in a test tube containing 10 ml of a buffer solution (trade name "Gibco PBS", Thermo Fisher Scientific) for 1 hour. Next, 1 ml of the buffer solution (hereinafter, "1/1 solution") after immersing each sample was placed in a test tube containing 9 ml of the buffer solution to prepare a diluted solution (1/10 diluted solution). A 1/100 diluted solution, a 1/1000 diluted solution, and a 1/10000 diluted solution were prepared in the same manner except that the dilution ratio with the buffer solution was changed.
Next, 0.050 ml was collected from 1/1 solution of each sample and smeared on a stamp medium (trade name: Petancheck 25 PT1025, manufactured by Eiken Kasei Co., Ltd.). By repeating this operation, two stamp media smeared with 1/1 solution were prepared for each sample. A total of four stamp media were placed in a constant temperature bath (trade name: IS600; manufactured by Yamato Scientific Co., Ltd.) and cultured at a temperature of 37 ° C. for 24 hours. The number of colonies generated for each stamp medium related to the 1/1 solution for each sample was counted, and the average value was calculated.
For the 1/10 diluted solution, the 1/100 diluted solution, the 1/1000 diluted solution, and the 1/10000 diluted solution, two smeared stamp media were prepared for each diluted solution and cultured. Then, the number of colonies generated for each stamp medium related to each diluted solution for each sample was counted, and the average value was calculated. The results are shown in Table 3.

As described above, the sample No. The number of bacteria in 0.050 ml of the 1/1 solution according to 8-1 was 210000 (CFU). Then, the sample No. after the sterilization treatment. The number of bacteria in the 1/1 solution according to 8-2 and 8-3 was 0 (CFU). From this, the active oxygen supply device according to this embodiment can sterilize Escherichia coli with a high efficiency of 99.999% ((210,000-1) / 210000 × 100) or more even when the treatment time is 2 seconds. I found out.

<Comparative Example 4>
Sample No. 8 described in Example 8. In the same manner as in the preparation method of 8-1, the sample No. C4-1 to C4-2 were prepared. This sample No. C4-1 to C4-2 were treated in the same manner as in Example 8 except that no voltage was applied to the plasma actuator of the active oxygen supply device. The processing time is the sample No. C4-1 is 2 seconds, sample No. C4-2 was set to 10 seconds. Finished sample No. For C4-1 to C4-2, the sample No. of Example 8 was used. Immersion in the buffer solution was carried out in the same manner as in 8-1. Then, a smeared stamp medium was prepared and cultured for 1/1 liquid of each sample. The average value was calculated by counting the number of colonies generated for each stamp medium related to the 1/1 solution for each sample. The results are shown in Table 4.

Sample No. after treatment. From the culture result of 1/1 solution of C4-1, the sample No. after the treatment was obtained. The number of bacteria present in 0.050 ml of the 1/1 solution according to C4-1 was 52 (CFU). On the other hand, sample No. The number of bacteria present in 0.050 ml of the 1/1 solution according to C4-2 was 0 (CFU). Therefore, in this comparative example, the sterilization rate of Escherichia coli when the treatment time was 2 seconds was 99.98% (= (210000-52) / 210000 × 100).
In Example 8, as described above, the sterilization rate when the treatment time was 2 seconds was 99.999% or more, so that the treatment with only ultraviolet rays was compared with the treatment in which ultraviolet irradiation and active oxygen were used in combination. It was confirmed that the sterilization efficiency was inferior.

<Comparative Example 5>
Sample No. 8 described in Example 8. In the same manner as in the preparation method of 8-1, the sample No. C5-1 to C5-2 were prepared. This sample No. C5-1 to C5-2 were treated in the same manner as in Example 8 except that the ultraviolet lamp of the active oxygen supply device was not turned on. Therefore, the sample No. C5-1 and C5-2 were treated with ozone in the induced flow. The processing time is the sample No. C5-1 is 2 seconds, sample No. C5-2 was set to 10 seconds. Finished sample No. For C5-1 to C5-2, the sample No. of Example 8 was used. Immersion and dilution in the buffer solution were carried out in the same manner as in 8-1. Next, the sample No. of Example 8 was used. In the same manner as in 8-1, two smeared stamp media were applied to each of the 1/1 solution, 1/10 diluted solution, 1/100 diluted solution, 1/1000 diluted solution and 1/10000 diluted solution for each sample. It was prepared and cultured. Then, the number of colonies generated for each stamp medium related to the 1/1 solution and each diluted solution for each sample was counted, and the average value was calculated. The results are shown in Table 5.

Among the above results, the treated sample No. From the culture results of the 1/10000 diluted solution of C5-1, the sample No. after the treatment was determined. It was found that the number of bacteria present in 0.050 ml of the 1/1 solution according to C5-1 was 19 × 10 ⁴ = 190000 (CFU). Therefore, the sample No. In the experimental example using C5-1, the sterilization rate of Escherichia coli was 9.5% (= (210000-190000) / 210000 × 100).
In addition, the sample No. after the treatment. From the culture results of the 1/10000 diluted solution of C5-2, the sample No. after the treatment was determined. It was found that the number of bacteria present in 0.050 ml of the 1/1 solution according to C5-2 was 8 × 10 ⁴ = 80000 (CFU). From this, the sample No. In the experimental example using C5-2, the sterilization rate of Escherichia coli was 61.9% (= (210000-80000) / 210000 × 100).

In Example 8, the sterilization rate was 99.999% or more even when the treatment time was 2 seconds. Therefore, the treatment with ozone alone was compared with the treatment using UV irradiation and active oxygen in combination. It was confirmed that the sterilization efficiency was significantly inferior.

<Example 9>
Sample No. in Example 8. In the preparation of 8-1, the slide glass was changed to a qualitative filter paper (product number: No. 5C, manufactured by Advantech) having a length of 3 cm and a width of 1 cm. Further, the bacterial solution was only dropped on one surface of the filter paper. Other than these, sample No. Sample No. 8-1 in the same manner. 9-1 was prepared.
Next, sample No. The following operations were performed for 9-1.
A recess of 3.5 cm in length, 1.5 cm in width and 2 mm in depth was provided in the center of a plastic flat plate having a length of 30 cm, a width of 30 cm and a thickness of 5 mm. A filter paper having a length of 3.5 cm and a width of 1.5 cm was laid in the recess. On this filter paper, the sample No. 9-1 was installed so that the lower surface of the fungal droplet faced the filter paper laid at the bottom of the recess. Then, on the upper surface of the plastic plate, an active oxygen supply device is provided so that the center in the longitudinal direction of the opening coincides with the center in the longitudinal direction of the recess and the center in the width direction of the recess is in the lateral direction of the recess. I placed it so that it coincided with the center of. Since the depth of the recess is 2 mm and the thickness of the filter paper is 1 mm or less, the bacterial solution adhering surface of each sample did not come into direct contact with the opening of the active oxygen supply device. Next, the active oxygen supply device was operated, and the lower surface of the fungal droplets of the filter paper was treated with an induced flow containing active oxygen. The processing time was 10 seconds. Further, in the treatment process using the active oxygen supply device, the time from the dropping of the bacterial solution to the filter paper to the immersion in the buffer solution was set to 60 seconds so that the filter paper on which the bacterial solution was dropped did not dry.

Finished sample No. 9-1 was immersed in a test tube containing 10 ml of a buffer solution (trade name "Gibco PBS", Thermo Fisher Scientific) together with a filter paper laid at the bottom of the recess for 1 hour. Then, 1 ml of the buffer solution after immersion (hereinafter referred to as "1/1 solution") was placed in a test tube containing 9 ml of the buffer solution to prepare a diluted solution (1/10 diluted solution). A 1/100 diluted solution, a 1/1000 diluted solution, and a 1/10000 diluted solution were prepared in the same manner except that the dilution ratio with the buffer solution was changed.
Next, 0.050 ml was collected from the 1/1 solution and smeared on a stamp medium (trade name: Petancheck 25 PT1025 manufactured by Eiken Kasei Co., Ltd.). By repeating this operation, two stamp media smeared with 1/1 liquid were prepared. A total of two stamp media were placed in a constant temperature bath (trade name: IS600; manufactured by Yamato Scientific Co., Ltd.) and cultured at a temperature of 37 ° C. for 24 hours. The number of colonies generated for each stamp medium related to the 1/1 liquid was counted, and the average value was calculated.
For the 1/10 diluted solution, the 1/100 diluted solution, the 1/1000 diluted solution, and the 1/10000 diluted solution, two smeared stamp media were prepared for each diluted solution and cultured. Then, the number of colonies generated for each stamp medium related to each diluted solution was counted, and the average value was calculated.

<Comparative Example 6>
Sample No. Sample No. 9-1 in the same manner. C9 was prepared.
This sample No. C9 was treated in the same manner as in Example 9 except that no voltage was applied to the plasma actuator of the active oxygen supply device. That is, the sample No. Only UV light was applied to C9. The processing time was 10 seconds. Finished sample No. Regarding C9, the sample No. of Example 9 was used. It was immersed in the buffer solution in the same manner as in 9. A 1/1 solution and a 1/10 to 1/10000 diluted solution were prepared in the same manner as in Example 9 except that the obtained buffer solution after immersion was used. A stamp medium was prepared and cultured in the same manner as in Example 9 except that the prepared 1/1 solution and 1/10 to 1/10000 diluted solution were used, and each stamp medium related to the 1/1 solution and each diluted solution was prepared. The number of colonies that occurred in was counted, and the average value was calculated.

<Reference example 1>
Sample No. Sample No. 9-1 in the same manner. R1 was prepared.
Untreated sample No. R1 was immersed in a test tube containing 10 ml of a buffer solution (trade name "Gibco PBS", Thermo Fisher Scientific) for 1 hour. Then, 1 ml of the buffer solution after immersion (hereinafter referred to as "1/1 solution") was placed in a test tube containing 9 ml of the buffer solution to prepare a diluted solution (1/10 diluted solution). A 1/100 diluted solution, a 1/1000 diluted solution, and a 1/10000 diluted solution were prepared in the same manner except that the dilution ratio with the buffer solution was changed.
Next, 0.050 ml was collected from the 1/1 solution and smeared on a stamp medium (Petancheck 25 PT1025 manufactured by Eiken Kasei Co., Ltd.). By repeating this operation, two stamp media smeared with 1/1 liquid were prepared. A total of two stamp media were placed in a constant temperature bath (trade name: IS600; manufactured by Yamato Scientific Co., Ltd.) and cultured at a temperature of 37 ° C. for 24 hours. Sample No. The number of colonies generated for each stamp medium related to the 1/1 liquid for R1 was counted, and the average value was calculated.
For the 1/10 diluted solution, the 1/100 diluted solution, the 1/1000 diluted solution, and the 1/10000 diluted solution, two smeared stamp media were prepared for each diluted solution and cultured. Then, the number of colonies generated for each stamp medium related to each diluted solution was counted, and the average value was calculated.

The results of Example 9, Comparative Example 6 and Reference Example 1 are shown in Table 6.

From the culture results of the 1/1000 diluted solution of Reference Example 1, the sample No. It was found that the number of bacteria present in 0.050 ml of the 1/1 solution of R1 was 5 × 10 ³ = 5000 (CFU). In addition, the number of bacteria in 0.050 ml of the 1/1 liquid after the treatment according to Example 9 was 0 (CFU). From this, it was found that the sterilization rate of Escherichia coli in Example 9 was 99.98% ((5000-1 / 5000) × 100) or more. On the other hand, from the culture results of the 1/1000 diluted solution according to Comparative Example 6, the sample No. after the treatment was obtained. The number of bacteria present in 0.050 ml of the 1/1 solution according to C6 was 2 × 10 ³ = 2000 (CFU). Therefore, it was found that the sterilization rate of Escherichia coli in Comparative Example 6 was 60% ((5000-2000) / 5000) × 100).
Here, the sample No. The treatment of active oxygen for 9-1 was carried out in Sample No. This was performed on the surface of the filter paper according to 9-1 opposite to the lower surface of the fungal droplet. From the results of Example 9 and Comparative Example 6, the sterilization treatment by actively supplying active oxygen to the object to be treated is not only the Escherichia coli existing on the surface of the filter paper but also the Escherichia coli existing inside the filter paper. It was found that the bacteria can be eradicated more reliably. In this respect, the sterilization method according to the present disclosure is superior to the sterilization method using only UV light in which only the irradiation surface of UV light is sterilized.

101: Active oxygen supply device (processing device using active oxygen), 102: Ultraviolet light source (ultraviolet lamp), 103: Plasma generator (plasma actuator), 104: Processed object, 104-1: Processed surface of the object to be processed, 105: induced flow, 106: opening, 107: housing

According to at least one aspect of the present disclosure, a housing having at least one opening, a plasma generator and an ultraviolet light source are provided in the housing, and the plasma generator sandwiches a dielectric. A plasma actuator in which a first electrode and a second electrode are provided and a voltage is applied between the two electrodes to generate an induced flow containing ultraviolet rays, the plasma actuator is such that the induced flow flows from the opening to the casing. The ultraviolet light source is arranged so as to flow out of the body, and the ultraviolet light source provides an active oxygen supply device that irradiates the induced flow with ultraviolet rays and generates active oxygen in the induced flow.

Further, according to at least one aspect of the present disclosure, a processing device for treating the surface of the object to be treated with active oxygen, a housing having at least one opening, and a plasma generating device inside the housing. And an ultraviolet light source, the plasma generator is provided with a first electrode and a second electrode with a dielectric sandwiched between them, and a voltage is applied between the two electrodes to generate an induced flow containing ozone. The plasma actuator is an actuator, and the plasma actuator is arranged so that the induced flow flows out of the housing through the opening, and the ultraviolet light source irradiates the induced flow with ultraviolet rays and is in the induced flow. Provided is a treatment device using active oxygen to generate active oxygen.

Further, according to at least one aspect of the present disclosure, it is a treatment method for treating the surface of the object to be treated with active oxygen.
A housing having at least one opening, a plasma generator and an ultraviolet light source are provided in the housing, and the plasma generator is provided with a first electrode and a second electrode with a dielectric interposed therebetween. , A plasma actuator that generates an induced flow containing ozone by applying a voltage between both electrodes, and the plasma actuator is arranged so that the induced flow flows out of the housing through the opening. The ultraviolet light source has a step of irradiating the induced flow with ultraviolet rays to prepare a processing device using active oxygen to generate active oxygen in the induced flow, a processing device using the active oxygen, and the object to be treated. Is placed at a relative position where the surface of the object to be treated is exposed when the induced flow is discharged from the opening, and the induced flow is discharged from the opening to allow the object to be treated. A step of treating the surface of the above with active oxygen and a method of treating with active oxygen are provided.

Claims (11)

A plasma generator and an ultraviolet light source are provided in a housing having at least one opening.
The plasma generator is a plasma actuator in which a first electrode and a second electrode are provided with a dielectric interposed therebetween, and an induced flow containing ozone is generated by applying a voltage between the two electrodes.
The plasma actuator is arranged so that the induced flow flows out of the housing through the opening.
The ultraviolet light source is an active oxygen supply device, which irradiates the induced flow with ultraviolet rays to generate active oxygen in the induced flow. The active oxygen supply device according to claim 1, wherein the peak wavelength of ultraviolet rays emitted by the ultraviolet light source is 220 nm to 310 nm. The active oxygen supply device according to claim 1 or 2, wherein the illuminance of ultraviolet rays in the opening is 40 μW / cm ² or more. The active oxygen supply device according to any one of claims 1 to 3, wherein the amount of ozone generated per unit time in the plasma actuator in a state where the induced flow is not irradiated with the ultraviolet rays is 15 μg / min or more. .. When the opening of the active oxygen supply device is directed vertically downward, the direction is from the edge of the first electrode of the plasma actuator along the portion of the dielectric not covered by the first electrode. The active oxygen supply device according to any one of claims 1 to 4, wherein the narrow angle θ formed by the extension line and the horizontal plane is 0 ° to 90 °. The active oxygen supply device according to any one of claims 1 to 5, wherein the distance between the ultraviolet light source and the plasma generator is 10 mm or less. The active oxygen supply device according to any one of claims 1 to 6, wherein the ultraviolet light source is arranged so as to be able to irradiate an object to be processed placed outside the housing through the opening. A treatment device that treats the surface of the object to be treated with active oxygen.
A plasma generator and an ultraviolet light source are provided in a housing having at least one opening.
The plasma generator is a plasma actuator in which a first electrode and a second electrode are provided with a dielectric interposed therebetween, and an induced flow containing ozone is generated by applying a voltage between the two electrodes.
The plasma actuator is arranged so that the induced flow flows out of the housing through the opening.
The ultraviolet light source is a treatment device using active oxygen, which comprises irradiating the induced flow with ultraviolet rays to generate active oxygen in the induced flow. The treatment device using active oxygen according to claim 8, wherein the ultraviolet light source is arranged so that the surface of the object to be treated can be irradiated. It is a treatment method that treats the surface of the object to be treated with active oxygen.
A plasma generator and an ultraviolet light source are provided in a housing having at least one opening.
The plasma generator is a plasma actuator in which a first electrode and a second electrode are provided with a dielectric sandwiched between them, and an induced flow containing ozone is generated by applying a voltage between the two electrodes. The plasma actuator is a plasma actuator. The induced flow is arranged so as to flow out of the housing through the opening, and the ultraviolet light source irradiates the induced flow with ultraviolet rays to generate active oxygen in the induced flow. The process of preparing the equipment and
A step of placing the treatment device using active oxygen and the object to be treated at a relative position where the surface of the object to be treated is exposed when the induced flow is discharged from the opening.
A method for treating with active oxygen, which comprises a step of allowing the induced flow to flow out from the opening and treating the surface of the object to be treated with active oxygen. The treatment method using active oxygen according to claim 10, wherein the distance between the ultraviolet light source and the surface of the object to be treated is 10 mm or less.

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