JP2003153989A - Method of sterilization - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of sterilization for immediately exhibiting the sterilization effect, producing little chlorine smell, without wetting the interior of a room, a person or an article in the room. SOLUTION: A spray device is used in the method of sterilization. The spray device has a spray nozzle facing toward the inside of a hollow cylinder at one end of the cylinder, a drip tray outside at the other end of the cylinder, and at least one spout on the side of the cylinder. The end to which the spray nozzle is attached in higher than the end to which the drip tray is attached, and preferably, the hollow cylinder is substantially stood vertically. Electrolytic water obtained by electrolyzing the aqueous solution including hypochlorous acid, or preferably, water including a compound to generate chlorine ions in water, is sprayed from the spray nozzle and dispersed from the spout.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indoor space such as a hospital room, a food processing plant, a residence, an office, meat, fish and vegetables, articles such as knives and cutting boards that handle them, workers such as human bodies and clothes. This is a sterilization method for the outer surface.

[0002]

2. Description of the Related Art In recent years, nosocomial infections have increased in hospitals, and in particular, symptoms in which bacteria resistant to antibiotics are the source of infection have been found, and reliable sterilization methods in hospital rooms and hospital facilities are required. In addition, in order to prevent food poisoning, it has become necessary to improve the hygiene concept and to sterilize the places and facilities where food is handled. Bacteria include those floating in spaces such as hospital rooms, food factories, kitchens, houses, and offices, and those that adhere to the surfaces of walls, floors, ceilings, and indoor items that surround the space. If you go to a place equipped with appropriate breeding conditions by moving with the movement of animals or the flow of air, there will be explosive breeding there. Further, in those places, bacteria are brought in from the outside together with the person entering the place and the goods to be brought in, and therefore, a sterilization method that quickly shows an effect is desired.

Methods for killing bacteria have long been wiped with alcohols, aqueous solutions of quaternary ammonium chloride compounds such as benzalkonium chloride and benzethonium chloride, and hypochlorite solutions. This method works only on the wiped area and is extremely incomplete in a wide range of complicated structures. Therefore, spraying of bactericidal solution such as aqueous solution containing hypochlorous acid, gas fumigation,
It is carried out by making the most of each characteristic depending on the circumstances such as ultraviolet irradiation, ozone release, sterilization by light using the catalytic action of titanium dioxide, or a method of capturing bacteria in the air by a filter.

[0004] Hypochlorous acid is a typical bactericide, has a strong oxidizing power, and has a strong killing power for a wide variety of bacteria. By making this into an aqueous solution, it is atomized. Can sterilize a wide space and area. In this method, not only a compound containing hypochlorous acid or a compound that produces hypochlorous acid in water is used as an aqueous solution, but also an aqueous solution containing chlorine ion is electrolyzed to generate hypochlorous acid. A method of using this as an aqueous solution has been proposed. For example, a method for sterilizing and sterilizing a space by atomizing electrolytically strongly acidic water (water containing hypochlorous acid) obtained by electrolyzing water containing chlorine ions by a sprayer [JP-A-7-20465]
3, JP-A-8-71136, and JP-A-11-1694.
41], a method of sterilizing and sterilizing a space by atomizing with ultrasonic waves [JP-A-5-176977, JP-A-7-3281]
00, JP-A-10-316517, JP-A-11-1
No. 69441], a method of atomizing with ultrasonic waves and placing this on an air stream from a blowing means to diffuse it [JP-A 2000-
197689, JP 2000-300169 A] and the like. Other examples of sterilization at specific locations include:
A method of directly spraying on meat, fish, etc. [Japanese Patent Laid-Open No. 10-17
9020], sterilization in a refrigerator [JP-A-2000-2920]
No. 52] Sterilization of human fingers [JP-A-6-321188,
JP-A-11-241381] and the like.

In the sterilization method for a room or a wide area, the main purpose is to make the bactericidal solution into fine particles by atomizing the bactericidal solution using an ultrasonic device as described above and further blowing air to disperse the particles. The examination has been advanced. However, if an aqueous solution containing hypochlorous acid is made into fine particles, the chlorine odor becomes strong, and conversely, if the chlorine odor is suppressed, there is a problem that sterilization will not be sufficient, and there is a limit to adopting it in a space where people live or go in and out. was there. On the other hand, in the method using a mechanical atomizer, large fog particles cause "wetness" in a room, articles, clothes, and the like, and there is a limitation in a place to be applied.

[0006]

In order to solve the above problems, an object of the present invention is to provide a sterilizing method which instantly exhibits a sterilizing effect, has a small chlorine odor, and does not wet a room, a person or an article. To provide.

[0007]

[Means for Solving the Problems] In order to achieve the above object,
As a result of detailed consideration of the behavior of hypochlorous acid when an aqueous solution containing hypochlorous acid is made into fine particles, the present inventors have found that in the case of hypochlorous acid, it has a moderate size rather than making fine particles. It has been found that the sterilizing effect can be further enhanced by making the mist particles uniform.

That is, the invention of claim 1 is a sterilization method, which has a spray nozzle directed toward the inside of the hollow cylinder at one end of the hollow cylinder, a droplet receiving tray outside the spray nozzle at the other end, and a side portion at the side. Uses a spraying device having one or more outlets, and the end with the spray nozzle is installed higher than the end with the liquid drop tray,
An aqueous solution containing hypochlorous acid is sprayed from the spray nozzle and sprayed from the outlet.

A second aspect of the present invention is the sterilization method according to the first aspect, wherein the spraying device is such that the hollow cylinder is substantially vertical, the spray nozzle is at the upper end, the liquid drop tray is at the lower end, and the side is 1 It is characterized by having more than one outlet.

The invention of claim 3 is the sterilization method according to claim 1 or 2, wherein the hollow cylinder end portion having the liquid drop tray and the liquid drop tray are sprayed with an aqueous solution containing hypochlorous acid from the outlet. It is characterized by being isolated from the space.

A fourth aspect of the invention is the sterilization method according to the first aspect, wherein the aqueous solution containing hypochlorous acid is electrolyzed water obtained by electrolyzing water containing a compound that produces chlorine ions in water. It is characterized by being.

The invention of claim 5 is the sterilization method according to claim 1, wherein the aqueous solution containing hypochlorous acid is strongly acidic electrolyzed water obtained on the anode side by electrolyzing water containing chlorine ions in water. It is characterized by being.

The invention of claim 6 is the sterilization method according to claim 5, wherein the strongly acidic electrolyzed water has a pH of 2.3 to 2,7 and an oxidation-reduction potential (ORP) of 961 to 1180 mv. I am trying.

The invention of claim 7 is the sterilization method according to claim 1, characterized in that the aqueous solution containing hypochlorous acid further contains a surfactant.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic view showing a spraying device of the present invention, in which the spraying device 1 has a hollow cylinder end 4 at one end of a hollow cylinder 2 with a spray nozzle 6 and a hollow cylinder end 5 at the other end with a droplet receiving tray. 7 and one or more outlets 3 on the side of the hollow cylinder.
have. Aqueous solution containing hypochlorous acid is spray nozzle 6
Is sprayed toward the inside of the hollow cylinder 2, and the sprayed mist particles pass through the hollow cylinder 2 and a part of the sprayed mist particles are sprayed from the outlet 3 to the target space. Fog particles that did not come out of the outlet 3,
Further, the particles associated in the hollow cylinder 2 flow as they are or while adhering to the inner wall of the hollow cylinder 2 and collected in the droplet receiving tray 7. Therefore, the hollow cylinder end portion 4 is positioned higher than the hollow cylinder end portion 5, and the hollow cylinder 2 is installed substantially vertically, preferably with the hollow cylinder end portion 4 facing upward, so that the large particles and the inner wall of the hollow cylinder 2 are placed. The droplets flowing through are easily collected in the droplet tray 7.

The hollow cylinder end 5 and the liquid drop receiving tray 7 are isolated from the space in which the aqueous solution containing hypochlorous acid is sprayed as the receiving portion 9, and are collected in the liquid drop receiving tray 7 in the receiving portion 9. It is preferable that the liquid is discharged from the liquid discharge port 8 and the gas discharged from the hollow cylinder end portion 5 is discharged from the gas discharge port 10.

The size and shape of the hollow cylinder 2 are not particularly limited, but in practice, it is a cylinder having a diameter of 3 to 7 cm.
The length is 40 to 250 cm. The hollow tube end 4 may be closed, but is preferably open. Air or other gas may be forcedly fed into the hollow cylinder 2 from the hollow cylinder end 4 by a pump or the like.

The form of the spray nozzle 6 is not limited, but for example, an aqueous solution containing hypochlorous acid is mixed with compressed air and sprayed from a small mouth (spray nozzle). At this time, the particle size of the mist 11 ejected from the spray nozzle 6 is controlled by the size of the nozzle tip, the discharge pressure of the aqueous solution containing hypochlorous acid, the discharge liquid amount, the compressed air pressure, the air amount, and the like. Therefore, it is preferable to experimentally confirm these relationships in advance for each device, and control based on the values. It is convenient to refer to many of the commercially available spray nozzles, which are provided as technical data by the seller. In the present invention, 80% or more of all particles have a particle size of 100 μm.
m or less, preferably 10 to 70 μm, and more preferably 30 to 50 μm.

The mist 11 emitted from the spray nozzle 6 usually has a wide particle size distribution, and contains mist particles having a large particle size. When such large fog particles are sprayed as they are toward a room, an article, or a human body, when they reach a solid surface, "wetting" occurs there. In the present invention, an aqueous solution containing hypochlorous acid is sprayed from the spray nozzle 6 into the hollow cylinder, and large fog particles and the fog particles that have become large by associating with each other after being sprayed are maintained as droplets or as a wall surface inside the hollow cylinder. The liquid flows upward, descends, and is collected in the liquid drop tray 7. Then, it is designed such that only the mist particles of a specific size are carried in the hollow cylinder by the flow of the compressed air used for spraying, pass through the hollow cylinder 2, and are blown out from the side blowout port 3. That is, since the fog 12 discharged from the outlet 3 does not contain fog particles having a large particle diameter, wetting of the indoor solid surface is reduced.

The blowout port 3 is a port for ejecting a part of the mist particles ejected by the spray nozzle 6 and flowing in the hollow cylinder 2 to the outside, and is located on the side surface of the hollow cylinder 2 away from the spray nozzle 6. It is provided. Of course, if you force the air,
When the end portion 4 of the hollow cylinder is opened, the surrounding air is sucked by the air flow accompanying the spraying, and the amount of air flowing in the hollow cylinder 2 increases accordingly. The optimum position and the optimum number should be determined according to the air volume. Generally, when the hollow cylinder 2 is installed vertically, the outlet 3 is 100 to 150 cm from the spray nozzle 6.
It is a remote place. The form of the blowout port 3 is determined in relation to the amount of spray, the amount of blowout, etc. and is not limited, but in practice, the diameter is about 2 to 5 cm, and for one hollow cylinder 1 to 3 units. The shape may be such that only a hole is formed in the side surface of the hollow cylinder, but the shape is preferably upward, preferably 30 to 50 ° upward. In this way, by making the blow-out port 3 project upward, when larger fog particles are about to come out of the blow-out port, they are returned to the inside of the cylinder, and only fog particles of an appropriate size are scattered outside. . Further, since large fog particles are suppressed from going out, droplets do not fall around the spraying device 1 and wet the floor.

The aqueous solution containing hypochlorous acid in the present invention is a compound which generates hypochlorous acid (HOCl) when dissolved in water, specifically chlorine, chlorine dioxide, sodium hypochlorite, hypochlorous acid. Potassium acid salt, calcium hypochlorite, chlorinated isocyanuric acid (and water-soluble metal salts such as sodium salt and potassium salt), chlorinated-5,5-dimethylhydantoin and the like may be an aqueous solution, but preferably chloride ion in water. It is electrolyzed water obtained by electrolyzing water to which a compound that generates is added. Examples of compounds that generate chloride ions in water include hydrochloric acid, sodium chloride, potassium chloride and the like. A further preferred embodiment of the present invention is acidic water containing hypochlorous acid, which is obtained on the anode side by performing electrolysis by separating the anode and the cathode with a diaphragm, and its typical water quality is pH 2.3. ~ 2.7, redox potential (OR
P) is 961-1180 mv. When the pH is lower than 2.3, not only hypochlorous acid becomes chlorine and it is easy to get out, but also protein denaturation is likely to proceed due to strongly acidic water, which may cause irritation when inhaled by humans and metal. However, this is not preferable because it causes severe corrosion. If the pH is higher than 2.7, the bactericidal effect may be inferior to that at 2.3 to 2.7.

The concentration of hypochlorous acid in the aqueous solution containing hypochlorous acid to be sprayed can be arbitrarily determined, but in practice it is 1 before spraying.
-500 ppm, preferably 5-200 ppm, more preferably 20-100 ppm.

Hypochlorous acid has the following equilibrium relationship in water.

[Chemical 1]

When water containing hypochlorous acid is atomized from the spray nozzle, chlorine (Cl ₂ ) in the above equilibrium relationship flows out from the surface of the fog particles into the air, so the above equilibrium equation shifts to the right. . Therefore, available chlorine in water, [ClO ⁻ , HCl
O, Cl ₂ ] concentration becomes lower and lower. This tendency is remarkable because the equilibrium goes to the right at lower pH. Since the smaller the fog particles, the larger the surface area, the more chlorine easily goes out into the air, and the effective chlorine concentration in the fog particles is usually lower than that before the mist was blown. On the other hand, the higher the chlorine concentration in the air, the greater the chlorine odor. Therefore, p
The lower H and the smaller the fog particles, the more intense the chlorine odor.

As mentioned above, an aqueous solution containing hypochlorous acid,
In particular, there has been proposed a sterilization method in which an acidic aqueous solution containing hypochlorous acid obtained by electrolysis is sprayed into a space by using ultrasonic waves to form fine particles. The fog produced by the ultrasonic device is very small, usually 10 μm or less, and substantially 2 to 5 μm. It has the advantage that it can efficiently spread over a wide area such as indoors because it is a fine mist particle, but in the case of water containing hypochlorous acid, chlorine is released from the particle surface into the air due to the above equilibrium relationship, and it is strong. The cause of chlorine odor is created, and the hypochlorous acid in the fog particles is diluted, and when the target solid surface is contacted with bacteria, the hypochlorous acid concentration becomes low.

It has been considered that the finer the mist particles are, the easier they are to float in the space, and the active ingredient can effectively contact the bacteria. However, in the case of hypochlorous acid, there is a situation that it will be dispersed as chlorine,
This idea is not always true. In the present invention, by making the particle size of the fog larger than in the ultrasonic device,
It is possible to relatively reduce the surface area of the fog particles, to reduce the diffusion of chlorine into the air, and to maintain the hypochlorous acid concentration in the fog particles at a high level, so that the bactericidal power can be maintained at a high level.

According to the present invention, the receiving portion 9 composed of the hollow cylinder end portion 5 and the droplet receiving tray 7 can be isolated from the space in which the aqueous solution containing hypochlorous acid is sprayed. By doing so, the amount of chlorine diffused into the target space can be reduced, and the chlorine odor can be significantly reduced. Whether atomized by an ultrasonic device or atomized by a mechanical atomizer, the hypochlorous acid component dispersed in the room is transformed into chlorine in any case and diffused into the room. Since a large part of the chlorine generated when converted to the outside can be guided to the outside of the target space, the chlorine in the room can be kept low and the chlorine odor can be reduced.

In the present invention, a surfactant can be further added to the aqueous solution containing hypochlorous acid. The surfactant may be selected from any of nonionic surfactants, cationic surfactants, and anionic surfactants, as long as it improves the wettability of water to the hydrophobic surface, Preferred are nonionic surfactants. The amount of the surfactant is optional, but it is 5 to 50 in the aqueous solution containing hypochlorous acid.
It is about ppm. Bacteria on the solid surface are killed by contact with an aqueous solution containing hypochlorous acid, and the surfactant makes this contact easier.

The mist sprayed by the atomizer generally has a wide particle size distribution and contains large mist particles. Furthermore, since there is an association of fog particles, there is a problem of "wetting" due to such large fog particles. In the present invention, the large fog particles that cause wetting are captured by the hollow cylinder 2, and only the fog particles of a proper size are blown out into the target space.
The problem of wetting is solved because it is taken out from the.

As described above, the fog particles of the present invention have a diameter larger than that of the ultrasonic fog particles, but are small enough to reach various places in the room. Since a large amount of chlorous acid remains, it has a great ability to kill bacteria. Further, when a surfactant is contained, it is considered that the contact between hypochlorous acid and bacteria is improved on the solid surface of the fog particles, and the bactericidal effect is increased. Also, the problem of "wetting" is ameliorated as large fog particles are removed before they are dispersed in the space of interest.

The spraying device used in the method of the present invention is installed at an arbitrary place in the target room, but in order to sterilize the space in the room, it is in the vicinity of the ejection port of the air to be ventilated and in the vicinity of the passage for people to enter and exit. Is particularly preferable. In addition, in order to sterilize articles and human bodies, it is installed so that the fog from the outlet is blown toward the target place. It is efficient to install multiple spraying devices if necessary.

[0032]

Example [Fungicide solution used in the test] Fungicide solution-A: 0.05% aqueous solution of sodium chloride was electrolyzed by separating the anode and the cathode with a diaphragm, and the solution on the anode side (strongly acidic water) was removed. Using.
Disinfectant liquid-B: In addition to disinfectant liquid-A, a nonionic surfactant [polyoxyethylene sorbitan monolaurate]
10 ppm was added. However, since the nonionic surfactant may be oxidatively decomposed by hypochlorous acid, it was added just before use.

[Test-1: Change in Composition of Fog Particles] Fungicide solution before spraying, fog particles discharged from the outlet of the spraying device of the present invention,
Alternatively, the fog particles generated by an ultrasonic device [ultrasonic humidifier ("FE-05KJV" (trade name) manufactured by Matsushita Electric Industrial Co., Ltd.)) were collected, and pH, ORP, and available chlorine amount were measured. It shows in Table 1.

[0034]

[Table 1] It was observed that spraying an aqueous solution containing hypochlorous acid did not significantly change the pH and ORP, but the available chlorine was extremely reduced. Further, when the spraying device of the present invention and the ultrasonic device were compared, it was found that the spraying device of the present invention had a larger amount of effective chlorine than that in the ultrasonic device.

[Test-2: Comparison of sterilizing power by sterilization method] Test apparatus of the present invention: A specimen is a sterilized membrane filter (a semicircular shape having a diameter of 4.7 cm) and Staphylococcus epiderma which is a white staphylococcus. Idis (Sta
phylococcus epidermidis)
To the suspension broth, which was cultured overnight in a broth,
I hung it on a hanger. The hanger on which the sample was hung was placed in the center of the test box, and the spraying device of the present invention was installed at each of two locations facing the sample from both sides so that the distance between the sample and the outlet was 40 cm. Test device used for comparison: An ultrasonic device [ultrasonic humidifier (manufactured by Matsushita Electric Industrial Co., Ltd., "FE-05KJV" (trade name)) was used.

Test method: The spraying device of the present invention or an ultrasonic device for comparison was installed in a box isolated from the surroundings, and first, the inside of the box was pre-sprayed for 5 minutes to make the inside of the box a mist atmosphere of a bactericide. After that, a hanger with six specimens with bacteria attached was placed and sprayed for a predetermined time. Samples are transferred to a flat culture medium and incubated at 37 ° C for 48 hours, and the number of bacteria on each sample is measured. The average value of the number of sheets was taken and recorded as the number of bacteria per one sample.
The spray liquid amount of the aqueous solution containing hypochlorous acid in the apparatus of the present invention was set to 5 mL / min (calculated from the spray amount from the spray nozzle and the amount collected in the droplet receiving pan). For comparison, a similar sample was placed 40 cm away from the outlet of the ultrasonic device, and an aqueous solution containing hypochlorous acid was sprayed at 5 mL / min.

The results are shown in Table 2.

[Table 2] From these results, it can be seen that the spraying device of the present invention has a higher sterilizing power than the ultrasonic device and the sterilizing effect appears earlier. Further, even when the spraying device of the present invention was used, it was observed that the sterilizing power was improved by adding the surfactant to the aqueous solution containing hypochlorous acid. The chlorine odor was less when using the spraying device of the present invention than when using the ultrasonic device.

[Test-3: Comparison of bactericidal activity against various bacteria] A bactericidal solution containing 10 ppm of a nonionic surfactant [polyoxyethylene sorbitan monolaurate]
B, using the spraying device of the present invention of Test-2,
The bactericidal activity against various bacteria was compared. The bacterium is Staphylococcus aureus.
cus aureus: Staphylococcus aureus, Escherichia coli:
E. coli), Pseudomonas species
omonas species: Pseudomonas aeruginosa, Salmonella species
s: Salmonella), and each was attached to the sample. In the test, six samples were suspended in the same manner as in Test-2, and the number of bacteria per sample was determined from the average value of four samples in the intermediate number of bacteria, and the test data was set once. It was carried out twice.

The results are shown in Table 3.

[Table 3] From these results, it can be seen that the method of the present invention has a large bactericidal activity against various bacteria and exhibits a bactericidal effect quickly.

[0040]

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to sterilize an indoor surface, an article, or an external surface of a human body, which exhibits an instant sterilizing effect, has a small chlorine odor, and does not wet the room, a person, or an article. It is effective when applied to places such as hospital rooms where there are many opportunities for bacterial infections and many people come and go.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a spraying device of the present invention.

[Explanation of symbols]

1: Spraying device 2: Hollow cylinder 3: outlet 4: End of hollow cylinder 5: Droplet saucer 6: Spray nozzle 7: Droplet saucer 8: Liquid outlet 9: Receiver 10: Gas outlet 11: Fog from the spray nozzle 12: Mist from the outlet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C02F 1/46 C02F 1/46 Z (72) Inventor Toshiaki Matsuo 2-7, Omorimoto-cho, Ota-ku, Tokyo Address 9 (72) Inventor Ta Naka Election 51, Kitsorimori, Kisogata-cho, Yuri-gun, Akita 1F Term (reference) 4C058 AA05 AA06 AA21 AA23 AA28 BB02 BB07 EE26 JJ07 JJ24 JJ28 4C080 AA07 BB05 BB06 CCKK CC02 HH04 02 LL04 LL09 MM01 MM09 NN01 QQ03 QQ16 QQ17 4D061 DA04 DB07 DB10 EA02 EB12 ED13 GA22 GA23

Claims (7)

[Claims] 1. A hollow cylinder has a spray nozzle directed to the inside of the hollow cylinder at one end, a droplet receiving pan outside the other end, and one or more outlets on the side, Further, an end where the spray nozzle is installed is higher than an end where the droplet receiving tray is installed, and an aqueous solution containing hypochlorous acid is sprayed from the spray nozzle and sprayed from the outlet. Sterilization method. 2. The spraying device is characterized in that a hollow cylinder is substantially vertical, and has a spraying nozzle at an upper end, a liquid drop tray at a lower end, and one or more outlets at a side part. The sterilization method according to claim 1. 3. The hollow cylinder end portion having the liquid droplet receiving tray and the liquid droplet receiving tray are isolated from the space in which the aqueous solution containing hypochlorous acid is sprayed from the outlet. The sterilization method described in 2. 4. The sterilization method according to claim 1, wherein the aqueous solution containing hypochlorous acid is electrolyzed water obtained by electrolyzing water containing a compound that produces chlorine ions in water. 5. The sterilizing method according to claim 1, wherein the aqueous solution containing hypochlorous acid is strongly acidic electrolyzed water obtained on the anode side by electrolyzing water containing chlorine ions in water. 6. The strongly acidic electrolyzed water has a pH of 2.3-2.
7. The sterilization method according to claim 5, wherein the oxidation-reduction potential (ORP) is 961-1180 mv. 7. The sterilization method according to claim 1, wherein the aqueous solution containing hypochlorous acid further contains a surfactant.