Long-term preservation of chlorine peroxy radical (cloo·), which is main active ingredient of chlorous acid water, through suppression of water molecule vibration

Abstract

The present invention provides technology for the long-term preservation of the scientific quality of the chlorine peroxy radical (ClOO·), which is the main active ingredient of chlorous acid water, through the suppression of water molecule vibration. Provided is a method for producing a frozen product of a chlorine peroxy radical solution, the method comprising: (1) preparing a solution containing the chlorine peroxy radical; and (2) freezing the solution containing the chlorine peroxy radical. The method comprises cooling the solution to -20°C or below. Also provided is a frozen product of a chlorine peroxy radical solution produced using the above method.

Description

Long-term storage of chlorine peroxide radicals (ClOO•), the main active ingredient in chlorous acid water, by suppressing the vibration of water molecules.

[0001] This invention relates to a technology for maintaining the chemical quality of chlorine peroxide radicals (ClOO•), the main active ingredient of chlorous acid water, for a long period of time, maintaining radical-active species in the liquid for a longer period, and preventing deterioration of chemical quality for a certain period.

[0002] Since receiving approval as a food additive in 2013, chlorous acid water has attracted attention as an antibacterial agent, disinfectant, germicidal agent, sterilizer, deodorizer, preservative, antiviral agent, and food additive disinfectant. Currently, chlorous acid water preparations on the market are used for a variety of purposes, not only for food but also for objects, people, and spaces. However, if chlorous acid water and its main active ingredient, chlorous acid, and its active molecular species, chlorine peroxide radical, are stored in a liquid state, the radicals will undergo molecularization in an attempt to stabilize, gradually deviating from the cyclic reaction, and as a result, they will gasify, causing a deterioration of their chemical quality. Therefore, even if this chlorous acid solution is stored under ideal conditions such as room temperature, unopened, and protected from light, and improvements are made to guarantee the chemical quality of its contents for one year, its quality assurance period appears extremely short compared to other chlorine oxide preparations such as sodium hypochlorite products, hypochlorous acid solutions, alcohol products, sodium chlorite products (e.g., MA-T), chlorine dioxide products (e.g., Cleverin), and stabilized chlorine dioxide (Biotalk), which poses a problem for both sales and manufacturing. However, we have now discovered a technology that maintains the chemical quality of chlorine peroxide radicals (ClOO•), the main active ingredient in chlorous acid solution, for a long period of time, allowing the radical-active species to remain in the solution for a longer period, and preventing any change (deterioration) in chemical quality for a certain period of time.

[0003] International Publication No. 2008 / 026607, International Publication No. 2014 / 188312, International Publication No. 2022 / 239801

[0004] The inventors have succeeded in discovering a technique to maintain the chemical quality of chlorite peroxide (ClOO•), the main active ingredient of chlorous acid water, and its active molecular species, chlorine peroxide radical, for a long period of time, and to better maintain the radical active species in liquid, thereby preventing changes (deterioration) in chemical quality for a certain period of time. This is achieved by freezing chlorous acid water, which is produced using salt, sodium chlorate, chlorine dioxide, etc. as raw materials, and then storing it in a frozen state. This suppresses the vibration of water molecules and blocks the kinetic energy transferred from water molecules to chlorine peroxide radicals.

[0005] 1) When a high-concentration product of chlorine peroxide radicals was filled into glass bottles, frozen, and then stored in a frozen state, the content measured by the KI method (as chlorous acid (HClO2 = 68.46)) and the free chlorine concentration measured by the colorimetric method (DPD method) remained unchanged (did not decrease) compared to when it was stored refrigerated at 10°C, and the chemical quality remained unchanged. Although not intended to be bound by theory, this may be proof that, according to the present invention, the degradation phenomenon due to voids (oxygen) observed at room temperature or refrigerated conditions does not occur.

[0006] 2) Although it is preferable to keep the concentration in the liquid uniform because a concentration gradient occurs during freeze-thaw cycles, it has been found that a few freeze-thaw cycles have no effect on the chemical quality. However, it has also been found that the fewer the number of freeze-thaw cycles, the closer the chemical quality to that before storage can be maintained, so it is preferable to limit the number of freeze-thaw cycles to a certain number. Furthermore, if the amount of void space is too large (for example, if the filling rate is less than 30%), chlorine dioxide gas is generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) during thawing, and as a result, the void space (oxygen) has an effect. Therefore, by using a storage container that can ensure a high filling rate (50% or more), the effect of the void space (oxygen) can be reduced.

[0007] 3) By freezing chlorous acid water and its main active ingredient, chlorous acid, and its active molecular species, chlorine peroxide radical, in liquid and then storing them at 0°C or below, the vibration of water molecules is stopped. It is thought that this allows the chlorine peroxide radical, the active molecular species of chlorous acid (the main active ingredient of chlorous acid water), to be stored (confined) within the ice molecular structure of water without interference from any other molecules.

[0008] 4) Furthermore, even if frozen storage at a high filling rate (50% or more) continues for a long period of time, the chlorine peroxide radical, which is the active molecular species of chlorous acid, the main active ingredient of chlorous acid water, remains trapped within the molecular structure of water fixed as ice. As a result, if this continues for a long time, the chlorine peroxide radical, which is the active molecular species of chlorous acid, the main active ingredient of chlorous acid water, can be stored for a long period (almost permanently) while maintaining its chemical quality.

[0009] 5) To date, no technology has been developed to maintain the chemical quality of chlorine peroxide radicals, which are the active molecular species of chlorous acid, the main active ingredient in chlorous acid water. If this technology is applied, its economic benefits would be immeasurable.

[0010] For example, this disclosure provides the following items: (Item 1) A method for producing a frozen chlorine peroxide radical solution, comprising: (1) preparing a solution containing chlorine peroxide radicals; and (2) freezing the solution containing chlorine peroxide radicals. (Item 2) The method according to Item 1, wherein the solution is an aqueous solution. (Item 3) The method according to Item 1, comprising cooling the solution to -20°C or below. (Item 4) The method according to Item 1, comprising cooling the solution to -80°C or below. (Item 5) The method according to Item 1, comprising adjusting the filling rate of the container storing the solution containing chlorine peroxide radicals to 50% or more. (Item 6) The method according to Item 1, comprising removing oxygen from the voids of the container storing the solution containing chlorine peroxide radicals and replacing it with an inert gas. (Item 7) The method according to Item 1, comprising sealing the container storing the solution containing chlorine peroxide radicals. (Item 8) The method according to Item 1, wherein preparing the solution containing chlorine peroxide radicals comprises thawing a frozen chlorine peroxide radical solution. (Item 9) The method according to Item 8, comprising stirring the thawed solution containing the chlorine peroxide radical. (Item 10) The method according to Item 5, comprising transferring the container used to store the solution containing the chlorine peroxide radical to another container. (Item 11) The method according to Item 1, wherein the solution containing the chlorine peroxide radical is produced by adding an acid to sodium chlorite. (Item 12) A frozen chlorine peroxide radical solution produced by the method according to any one of Items 1 to 11.

[0011] In this disclosure, the one or more of the above features are intended to be provided in combinations other than those explicitly stated. Further embodiments and advantages of this disclosure will be apparent to those skilled in the art, by reading and understanding the detailed description below as necessary.

[0012] This technology provides a way to maintain the chemical quality of chlorine peroxide radicals (ClOO•), the main active ingredient in chlorous acid water, over a long period of time, and to better maintain the radical active species in the liquid, thereby preventing changes (deterioration) in chemical quality for a certain period of time.

[0013] Figure 1 shows the time course of the chlorine peroxide radical (ClOO•) solution from Example 1 when stored under refrigeration. Figure 2-1 shows the time course of the free chlorine concentration (assuming Cl=35.45) from Example 1. Figure 2-2 shows the content (chlorous acid (HClO)) from Example 1. ２Figure 3 shows the results of the time course of the free chlorine concentration (assuming Cl=35.45) for each test section of Example 2. Figure 4 shows the UV spectrum of the Blank section for Test B of Example 2. Figure 5-1 shows the UV spectrum of Test section II-(α) for Test B of Example 2. Figure 5-2 shows the UV spectrum of Test section II-(β) for Test B of Example 2. Figure 6 shows the time course of the free chlorine concentration (assuming Cl=35.45) for each test section of Example 2 up to D+60. Figure 7 shows the time course of the content (assuming chlorous acid (HClO2=68.46)) for each test section of Example 2 up to D+60. Figure 8 shows the time course of the free chlorine concentration (assuming Cl=35.45) for each test section of Example 2 up to D+90. Figure 9 shows schematic diagrams of each test section of Example 3. Figure 10-1 shows a comparison of the time-dependent changes in the free chlorine concentration (assuming Cl=35.45) for each filling rate in each test section of Example 3. Figure 10-2 shows a comparison of the time-dependent changes in the free chlorine concentration (assuming Cl=35.45) for each filling rate in each test section of Example 3. Figure 10-3 shows a comparison of the time-dependent changes in the free chlorine concentration (assuming Cl=35.45) for each filling rate in each test section of Example 3. Figure 10-4 shows a comparison of the time-dependent changes in the free chlorine concentration (assuming Cl=35.45) for each filling rate in each test section of Example 3. Figure 10-5 shows a comparison of the time-dependent changes in the free chlorine concentration (assuming Cl=35.45) for each filling rate in each test section of Example 3. Figure 11 shows a comparison of the free chlorine concentration (assuming Cl=35.45) for the Blank section (100% filling rate) and each filling rate (10-90%) during each storage period of Example 3. Figure 12 shows a comparison of the free chlorine concentration (assuming Cl=35.45) for the Blank section (100% filling rate) and each filling rate (10-90%) during each storage period of Example 3. Figure 13 shows a comparison of the free chlorine concentration (assuming Cl=35.45) for the Blank section (100% filling rate) and each filling rate (10-90%) during each storage period of Example 3. Figure 14 shows the change in the UV spectrum over time (D+0 to D+90) of the Blank section (100% filling rate) of Example 3. Figure 15 shows the UV spectrum (D+30) of Test section I-α (N2) of Example 3. Figure 16 shows the UV spectrum (D+60) of Test section I-α (N2) in Example 3.Figure 17 shows the UV spectrum (D+90) of Test section I-α (N2) in Example 3. Figure 18 shows the UV spectrum (D+30) of Test section I-β (CO2) in Example 3. Figure 19 shows the UV spectrum (D+60) of Test section I-β (CO2) in Example 3. Figure 20 shows the UV spectrum (D+90) of Test section I-β (CO2) in Example 3. Figure 21 shows the UV spectrum (D+30) of the Control section in Example 3. Figure 22 shows the UV spectrum (D+60) of the Control section in Example 3. Figure 23 shows the UV spectrum (D+90) of the Control section in Example 3. Figure 24 shows the decrease in the 'content (as chlorous acid (HClO2=68.46))' of Test section I-(α) in Example 3. Figure 25 shows the decrease (consumption) of the "content (as chlorous acid (HClO2=68.46))" in each test section (D+60) of Example 3. Figure 26 shows the mechanism of decrease in "content (as chlorous acid (HClO2=68.46))" associated with a decrease in "free chlorine concentration (as Cl=35.45)" in low-fill-rate products. Figure 27 shows the mechanism of decrease in "content (as chlorous acid (HClO2=68.46))" associated with a decrease in "free chlorine concentration (as Cl=35.45)" in low-fill-rate products. Figure 28 shows the decrease in "content (as chlorous acid (HClO2=68.46))" depending on the filling rate of each test section (D+90) of Example 3. Figure 29 shows a schematic diagram of test section (1) of Example 4. Figure 30 shows the UV spectrum of test section (1) of Example 4. Figure 31 shows a comparison of the 'free chlorine concentration (assuming Cl=35.45)' and 'content (as chlorous acid (HClO2=68.46)' with respect to the number of freeze-thaw cycles in test section (1) of Example 4. Figure 32 shows a schematic diagram of test section (2) of Example 4. Figure 33 shows a schematic diagram of test section (3) of Example 4. Figure 34 shows the UV spectrum of test section (2) of Example 4. Figure 35 shows the UV spectrum of test section (3) of Example 4. Figure 36 shows a comparison of the 'free chlorine concentration (assuming Cl=35.45)' in Cont section, test section (2), and test section (3) of Example 4. Figure 37 shows a comparison of the 'content (as chlorous acid (HClO2=68.46)' in Cont section, test section (2), and test section (3) of Example 4. Figure 38 shows schematic diagrams of test sections (4) and (5) of Example 4.Figure 39 shows the UV spectra of Test Group (4) and Test Group (5) of Example 4. Figure 40 shows the comparison of "free chlorine concentration (assuming Cl = 35.45)" among the Cont Group, Test Group (4), and Test Group (5) of Example 4. Figure 41 shows the comparison of "content (assuming chlorous acid (HClO2 = 68.46))" among the Cont Group, Test Group (4), and Test Group (5). Figure 42 shows a schematic diagram of the Cont Group of Example 4. Figure 43 shows a schematic diagram of Test Group (6) of Example 4. Figure 44 shows the UV spectrum of the Cont Group of Example 4. Figure 45 shows the UV spectrum of Test Group (6) of Example 4. Figure 46 shows the comparison of "free chlorine concentration (assuming Cl = 35.45)" between the Cont Group and Test Group (6) of Example 4. Figure 47 shows the comparison of "content (assuming chlorous acid (HClO2 = 68.46))" between the Cont Group and Test Group (6) of Example 4. Figure 48 shows the UV spectra of Test Group (7) and Test Group (8) of Example 4. Figure 49 shows the UV spectra of the Cont Group and Test Group of Example 4. Figure 50 shows the comparison of "free chlorine concentration (assuming Cl = 35.45)" and "content (assuming chlorous acid (HClO2 = 68.46))" between Test Group (7) and Test Group (8) of Example 4. Figure 51 shows the comparison of "free chlorine concentration (assuming Cl = 35.45)" at each filling rate between the Cont Group and Test Group of Example 4. Figure 52 shows the comparison of "content (assuming chlorous acid (HClO2 = 68.46))" at each filling rate between the Cont Group and Test Group of Example 4. Figure 53 shows the comparison of free chlorine concentration (assuming Cl = 35.45) in slow freezing (final temperature: -20°C) and rapid freezing (final temperature: -80°C) of Example 5. Figure 54 shows the comparison of content (assuming chlorous acid (HClO2 = 68.46)) in slow freezing (final temperature: -20°C) and rapid freezing (final temperature: -80°C) of Example 5.

[0014] Hereinafter, the present disclosure will be described in more detail. Throughout this specification, it should be understood that singular expressions include the concepts of their plural forms unless otherwise specified. Therefore, singular articles (e.g., in English, "a", "an", "the", etc.) should be understood to include the concepts of their plural forms unless otherwise specified. Also, the terms used in this specification should be understood to be used in the ordinary meanings used in the relevant field unless otherwise specified. Therefore, unless otherwise defined, all technical and scientific terms used in this specification have the same meanings as commonly understood by those skilled in the art to which this disclosure pertains. In case of conflict, this specification (including the definitions) shall prevail.

[0015] Abbreviations used in this specification have their conventional meanings within the scope of the relevant field unless otherwise specified.

[0016] The reference to "about" for a value or parameter in this specification includes variations of the value or parameter itself. Unless otherwise specified, for example, "about X" includes, in addition to "X" itself, values that allow an error of ±10%.

[0017] In this specification, "hypochlorous acid water" refers to an aqueous solution containing hypochlorous acid (HClO ２ ) used as a bactericide, which can stably maintain hypochlorous acid (HClO ２ ) over a long period of time. When a sample of hypochlorous acid water is measured with a spectrophotometer, if two absorption parts, one showing a peak near 260 nm and the other showing a peak near 350 nm, can be simultaneously confirmed in the UV spectrum between wavelengths of 240 to 420 nm, that is, when showing a double peak, the presence of hypochlorous acid water can be recognized.

[0018] Hypochlorous acid water can be prepared by the methods disclosed in International Publications WO2008 / 026607, WO2014 / 188310, WO2014 / 188311, WO2014 / 188312, WO2015 / 093062, WO2017 / 170904.

[0019] "Chlorous acid water" was designated as a food additive on February 1, 2013. It is a disinfectant whose main active ingredient is chlorous acid (HClO2). Chlorous acid (HClO2), the main active ingredient in "chlorous acid water," is a metastable chemical substance and is recognized by the US USDA and FDA as a particularly safe substance for use as a food additive and processing aid.

[0020] Moreover, "chlorous acid water" can exert a strong bactericidal effect even in the presence of organic matter, and it has received high praise from the National Institute of Health Sciences (NIHS) in its "2015 Survey on Norovirus Inactivation Conditions," which stated that "chlorous acid water was the only substance that could inactivate the virus to below the detection limit under all loading conditions." As a result, chlorous acid water is increasingly being included in the "Cooking Manual for Mass Catering Facilities" and other documents, in order of the occurrence of large-scale food poisoning incidents, along with revisions to the Food Sanitation Act Enforcement Regulations.

[0021] Furthermore, it is approved for manufacture and sale as a Class II disinfectant, and is mentioned in various guidelines such as the "Q&A on Norovirus" and the "Guidelines for Infectious Disease Control in Childcare Facilities" overseen by the Ministry of Health, Labour and Welfare, as well as related manuals such as the "Infection Control Manual for Elderly Care Facilities," and is a substance supplied to a wide range of markets in Japan's food hygiene and environmental hygiene markets.

[0022] Chlorous acid water, whose main active ingredient is chlorous acid, possesses a bactericidal power equivalent to or even greater than that of hypochlorous acid water and sodium hypochlorite. However, its reactivity is gradual, and it does not exhibit an instantaneous bactericidal effect (immediate action). Nevertheless, chlorous acid water has the characteristic of possessing precise bactericidal power while maintaining a stable bactericidal effect. This makes it possible to exert a bactericidal effect slowly but surely and accurately in polluted environments with a large amount of organic matter, which have been considered the most difficult environment for conventional chlorine oxide-based disinfectants (bactericidal power against microorganisms lurking in the dirt).

[0023] Therefore, it can inactivate resistant bacteria (such as heat-resistant bacteria that increase their resistance by forming spores, and antibiotic-resistant bacteria that are no longer affected by antibiotics), fungi such as molds and yeasts, and viruses (including both enveloped and non-enveloped viruses), which have previously been difficult to kill. Chlorous acid water does not need to be prepared before use, does not require any special generating equipment, can be used by anyone, anywhere, whenever and wherever needed, and is safe.

[0024] Furthermore, information regarding the effectiveness of "chlorous acid water" in the presence of organic matter is also available on the Ministry of Health, Labour and Welfare's website in the "Research Report on Norovirus Inactivation Conditions for FY2015 (National Institute of Public Health, Food Hygiene Management Department)."

[0025] It has been found that the active molecular species of chlorous acid, the main active ingredient in chlorous acid water, is the chlorine peroxide radical (Patent Document 3).

[0026] In this specification, "chlorine peroxide radical" refers to a peroxide radical having two oxygen atoms for every one chlorine atom, where the radical is located on an oxygen atom, not a chlorine atom. Therefore, it is different from chlorine dioxide radicals (O=Cl•=O), which have the radical on a chlorine atom. The difference between chlorine peroxide radicals and chlorine dioxide radicals can be confirmed by ESR measurement. Chlorine peroxide radicals have the structure of a peroxide radical, and are thought to have a Cl-O-O• structure, which is clearly different from the structure of chlorine dioxide radicals (O=Cl•=O). Chlorine peroxide radicals have absorbance at the absorption maximum wavelength of 350-360 nm. As a radical, they have low reactivity and can exist stably for long periods of time.

[0027] In this specification, "free chlorine," "free chlorine concentration," or "free residual chlorine concentration" refers to the value measured by the colorimetric method (DPD indicator) specified in Appendix 3 of the "Testing Method for Free Residual Chlorine and Combined Chlorine as Determined by the Minister of Health, Labour and Welfare pursuant to Article 17, Paragraph 2 of the Water Supply Act Enforcement Regulations," and is a value obtained by the oxidation of the DPD indicator.

[0028] (Preferred Embodiments) Preferred embodiments of the Disclosure are described below. The embodiments provided below are provided for a better understanding of the Disclosure, and it will be understood that the scope of the Disclosure is not limited to the descriptions below. Accordingly, it will be obvious that those skilled in the art can make appropriate modifications within the scope of the Disclosure by taking into consideration the descriptions herein. It will also be understood that the embodiments of the Disclosure below can be used individually or in combination.

[0029] In one aspect of this disclosure, a method for producing a frozen chlorine peroxide radical solution is provided. The method for producing a frozen chlorine peroxide radical solution according to this disclosure comprises (1) preparing a solution containing chlorine peroxide radicals, and (2) freezing the solution containing chlorine peroxide radicals. Even if it is conceivable to store a solution of an unstable substance such as a radical at a low temperature, such as by refrigeration, it is not readily conceivable to freeze and store a solution containing an unstable substance for a long period of time, because the unstable substance may be destroyed when the solution is frozen and / or when the frozen product is thawed.

[0030] In one embodiment of the present disclosure, the solution in the method is an aqueous solution. Chlorine peroxide radicals (ClOO•) in aqueous solutions, even during refrigerated storage, attempt to stabilize themselves by molecularizing to facilitate the cyclic reaction. However, there is no way to stabilize these radicals in the solution for a long period of time, making long-term storage impossible. The frozen product of the present invention solves this problem.

[0031] In the method of this disclosure, the free chlorine concentration (assuming Cl = 35.45) of the chlorine peroxide radical solution that can be used may be 10,000 ppm or more, 15,000 ppm or more, 20,000 ppm or more, or 20,000 ppm or more. In the method of this disclosure, even such high-concentration chlorine peroxide radical solutions can be stored for a long period of time and have high commercial value.

[0032] In one embodiment of the present disclosure, the method comprises cooling the solution to -20°C or below, -30°C or below, -40°C or below, -50°C or below, -60°C or below, -70°C or below, -80°C or below, -90°C or below, or -100°C or below.

[0033] In one embodiment of the present disclosure, the method includes cooling the solution to -80°C or below.

[0034] In one embodiment of the present disclosure, the method comprises adjusting the filling rate of the container storing the solution containing the chlorine peroxide radical to 10% or more, 15% or more, 20% or more, 25% or more, 30% or more, 35% or more, 40% or more, 45% or more, 50% or more, 55% or more, 60% or more, 65% or more, 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, 95% or more, 96% or more, 97% or more, 98% or more, 99% or more, or 100%. As shown in Examples 3 to 4 described later, the effect of voids (oxygen) can be reduced by increasing the filling rate. In this specification, the filling rate is calculated by dividing the volume of the solution by the volume of the container.

[0035] In one embodiment of the present disclosure, the method includes removing oxygen from the voids of a container storing the solution containing chlorine peroxide radicals and replacing it with an inert gas. Any gas that does not react with chlorine peroxide radicals can be used as the inert gas, such as nitrogen gas, carbon dioxide gas, or noble gases (helium, neon, argon, krypton, xenon, radon). In the present invention, nitrogen gas may be a preferred inert gas. As shown in Example 3 later, removing oxygen from the voids can reduce the deterioration of the quality of the solution containing chlorine peroxide radicals due to oxygen during melting.

[0036] In one embodiment of the present disclosure, the method includes sealing a container that stores the solution containing the chlorine peroxide radical. Examples of containers for storing the solution containing the chlorine peroxide radical include those made of polyvinyl chloride or glass.

[0037] In one embodiment of the present disclosure, preparing the solution containing the chlorine peroxide radical in the method includes thawing a frozen solution containing the chlorine peroxide radical. Since a concentration gradient is formed in the thawed solution containing the chlorine peroxide radical, which is the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), it is preferable to stir the solution before further freezing or use.

[0038] In one embodiment of the present disclosure, the method includes transferring the solution containing the chlorine peroxide radical from one container to another. By transferring the container, the filling density can be adjusted.

[0039] In one embodiment of the present disclosure, the method is used to produce the solution containing the chlorine peroxide radical by adding an acid to sodium chlorite.

[0040] In one aspect of this disclosure, a frozen product of a chlorine peroxide radical solution produced by the above method is provided.

[0041] In this disclosure, slow freezing means cooling to a target temperature of -20°C, and rapid freezing means cooling to a target temperature of -80°C.

[0042] (Examples of the production of chlorous acid water and its use) The chlorous acid water used in this disclosure has characteristics discovered by the inventors. Chlorous acid water produced by any known method, such as those described in the above-mentioned literature, can be used. As a typical composition, for example, a mixture of 61.40% chlorous acid water, 1.00% potassium dihydrogen phosphate, 0.10% potassium hydroxide, and 37.50% purified water can be used (the 72% chlorous acid water sold by the applicant corresponds to 30,000 ppm chlorous acid), but is not limited to this. This agent reduces the decay of chlorous acid due to contact with organic matter under acidic conditions, while maintaining its bactericidal effect. Furthermore, it has the characteristics of generating only slight chlorine gas and suppressing the amplification of odors caused by the mixture of chlorine and organic matter.

[0043] In one embodiment, the chlorous acid water of the present disclosure can be produced by reacting an aqueous solution of sodium chlorate with sulfuric acid or an aqueous solution thereof in an amount and concentration that can maintain the pH of the aqueous solution at 3.4 or less to generate chloric acid, and then adding an amount of hydrogen peroxide equal to or greater than the amount required for the reduction reaction of the chloric acid.

[0044] In another embodiment, the chlorous acid water of this disclosure can be produced by reacting an aqueous solution of sodium chlorate with sulfuric acid or an aqueous solution thereof in an amount and concentration that can maintain the pH of the aqueous solution at 3.4 or less to generate chloric acid, and then adding an amount of hydrogen peroxide equal to or greater than the amount required for the reduction reaction of the chloric acid to the aqueous solution to produce chlorous acid, and then adding an inorganic acid or an inorganic salt, or two or more of them individually or in combination thereof, to adjust the pH to a range of 3.2 to 8.5.

[0045] Furthermore, in another embodiment, the chlorous acid water of this disclosure can be produced by reacting an aqueous solution of sodium chlorate with sulfuric acid or an aqueous solution thereof in an amount and concentration that can maintain the pH value of the aqueous solution at 3.4 or less to generate chloric acid, and then adding an amount of hydrogen peroxide equal to or greater than the amount required for the reduction reaction of the chloric acid to the aqueous solution to produce chlorous acid, and then adding one or more inorganic acids or inorganic acid salts, or organic acids or organic acid salts, or two or more of them, or a combination thereof, to adjust the pH value to within the range of 2.9 to 8.5.

[0046] Furthermore, in another embodiment, the chlorous acid water of the present disclosure can be produced by reacting an aqueous solution of sodium chlorate with sulfuric acid or an aqueous solution thereof in an amount and concentration that can maintain the pH value of the aqueous solution at 3.4 or less to generate chloric acid, and then adding an amount of hydrogen peroxide equal to or greater than the amount required for the reduction reaction of the chloric acid to the aqueous solution to which chlorous acid has been produced, and then adding an inorganic acid or inorganic salt, or two or more of them individually or in combination, to the aqueous solution, and then adjusting the pH value to a range of 3.2 to 8.5.

[0047] In another embodiment, the inorganic acid used in the above method may be carbonic acid, phosphoric acid, boric acid, or sulfuric acid.

[0048] Furthermore, in another embodiment, the inorganic salt can be a carbonate, inorganic hydroxide, phosphate, or borate.

[0049] In another embodiment, sodium carbonate, potassium carbonate, sodium bicarbonate, or potassium bicarbonate can be used as the carbonate.

[0050] Furthermore, in another embodiment, sodium hydroxide or potassium hydroxide, calcium hydroxide, or barium hydroxide can be used as the inorganic hydroxide.

[0051] Furthermore, in another embodiment, disodium hydrogen phosphate, dihydrogen dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, or potassium dihydrogen phosphate can be used as the phosphate.

[0052] In another embodiment, sodium borate or potassium borate can be used as the borate.

[0053] Furthermore, in another embodiment, succinic acid, citric acid, malic acid, acetic acid, or lactic acid can be used as the organic acid.

[0054] Furthermore, in another embodiment, as the organic acid salt, sodium succinate, potassium succinate, sodium citrate, potassium citrate, sodium malate, potassium malate, sodium acetate, potassium acetate, sodium lactate, potassium lactate or calcium lactate can be used.

[0055] In a method for producing an aqueous solution (chlorous acid water) containing chlorous acid (HClO ２ ) that can be used as a bactericidal agent, an aqueous solution of sodium chlorate (NaClO ３ ) is made acidic by adding sulfuric acid (H ２ SO ４ ) or an aqueous solution thereof, and the resulting chloric acid (HClO ３ ) is added with an amount of hydrogen peroxide (H ２ O ２ ) necessary for converting it to chlorous acid by a reduction reaction, thereby generating chlorous acid (HClO ２ ). The basic chemical reactions of this production method are represented by the following Formulas A and B.

[0056]

[0057] In Formula A, it shows that chloric acid is obtained by adding sulfuric acid (H ３ ) or an aqueous solution thereof in an amount and concentration that can maintain the pH value of the aqueous solution of sodium chlorate (NaClO ２ SO ４ ) within an acidic range. Next, in Formula B, it shows that chloric acid (HClO ３ ) is reduced by hydrogen peroxide (H ２ O ２ ) to generate chlorous acid (HClO ２ ).

[0058]

[0059] At that time, chlorine dioxide gas (ClO ２ ) is generated (Formula C), but by coexisting with hydrogen peroxide (H ２ O ２ ), through the reactions of Formulas D to F, chlorous acid (HClO ２ ) is generated.

[0060] By the way, the generated chlorous acid (HClO) ２ ) is caused by multiple chlorous acid molecules decomposing each other, or by chloride ions (Cl - It has the property of quickly decomposing into chlorine dioxide gas or chlorine gas in the presence of chlorite (HClO) and hypochlorous acid (HClO) and other reducing agents. Therefore, in order to make it useful as a bacterial killer, chlorite (HClO) ２ It is necessary to prepare the product so that the state of ) can be maintained for a long period of time.

[0061] Therefore, the chlorous acid (HClO) obtained by the above method is obtained. ２ ) or chlorine dioxide gas (ClO ２ By adding an inorganic acid, inorganic acid salt, organic acid, or organic acid salt, either individually or in combination with two or more of them, to an aqueous solution containing these, a transition state is created, slowing down the decomposition reaction and allowing chlorous acid (HClO) to be produced for a long time. ２ ) can be maintained stably.

[0062] In one embodiment, the chlorous acid (HClO) obtained by the above method is used. ２ ) or chlorine dioxide gas (ClO ２ ) or an aqueous solution containing these can be used to which an inorganic acid or inorganic salt, specifically a carbonate or inorganic hydroxide, either individually or in combination with two or more of them, can be added.

[0063] In another embodiment, an aqueous solution containing an inorganic acid or inorganic acid salt, specifically a carbonate or inorganic hydroxide, either individually or in combination with two or more of them, can be used to which an inorganic acid, inorganic acid salt, organic acid, or organic acid salt is added individually or in combination with two or more of them.

[0064] In addition, in yet another embodiment, an aqueous solution produced by the above method can be used to which an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt is added individually or in combination with two or more other types.

[0065] Examples of the inorganic acids mentioned above include carbonic acid, phosphoric acid, boric acid, or sulfuric acid. Examples of inorganic salts include carbonates, inorganic hydroxides, phosphates, or borates. More specifically, carbonates include sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate; inorganic hydroxides include sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide; phosphates include disodium hydrogen phosphate, sodium dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, and dipotassium phosphate; and borates include sodium borate and potassium borate. Examples of the organic acids mentioned above include succinic acid, citric acid, malic acid, acetic acid, or lactic acid. Suitable organic salts include sodium succinate, potassium succinate, sodium citrate, potassium citrate, sodium malate, potassium malate, sodium acetate, potassium acetate, sodium lactate, potassium lactate, or calcium lactate.

[0066] When an acid and / or its salt is added, Na temporarily ＋ +ClO ２ － ⇔ Na - ClO ２ Ya K ＋ +ClO ２ － ⇔ K-ClO ２ Ya H ＋ +ClO ２ － ⇔ H-ClO ２ This creates a transition state, and chlorous acid (HClO) is produced. ２ ) Chlorine dioxide (ClO ２ This can slow down the progression to chlorous acid (HClO). ２ ) maintains for a long time, chlorine dioxide (ClO ２ ) produces less chlorous acid (HClO) ２ This makes it possible to produce an aqueous solution containing ).

[0067] The following illustrates the decomposition of chlorites in acidic solutions.

[0068]

[0069] As shown in this equation, the decomposition rate of a chlorite aqueous solution at a given pH increases as the pH decreases, i.e., as the acidity increases. In other words, the absolute rates of reactions (a), (b), and (c) in the above equation increase. For example, the proportion of reaction (a) decreases as the pH decreases, but the total decomposition rate fluctuates greatly, i.e., becomes large, so chlorine dioxide (ClO) ２ The amount of chlorine dioxide (ClO) produced also increases as the pH decreases. Therefore, the lower the pH value, the faster sterilization and bleaching will occur, but the amount of irritating and harmful chlorine dioxide gas (ClO) produced also increases. ２ This can make the work difficult and have adverse effects on human health. In addition, the reaction of chlorite with chlorine dioxide proceeds rapidly, making the chlorite unstable, and the time it can maintain its disinfecting power is extremely short.

[0070] Therefore, chlorous acid (HClO) ２ When adding the above-mentioned inorganic acid, inorganic acid salt, organic acid, or organic acid salt to an aqueous solution containing ), the pH value should be adjusted within the range of 2.9 to 8.5 from the viewpoint of suppressing the generation of chlorine dioxide and balancing it with the bactericidal effect.

[0071] The chlorous acid water of this disclosure may also be an aqueous solution obtained by adding hydrochloric acid to a saturated sodium chloride solution, electrolyzing it under acidic conditions in a non-diaphragm electrolytic cell (meaning one composed of an anode and cathode not separated by a diaphragm), adding sulfuric acid to make it strongly acidic, and reacting the chloric acid produced therein with hydrogen peroxide water. The chlorous acid water may be one of those listed in the 10th edition of the Japanese Food Additives Standards 2024 (Consumer Affairs Agency, Ministry of Health, Labour and Welfare).

[0072] The chlorous acid water disclosed herein also contains chlorine dioxide gas (ClO2). ２ By trapping (capture or adsorbing) chlorous acid (HClO) with an inorganic acid, inorganic acid salt, organic acid, or organic acid salt, or two or more of these individually or in combination, a transition state is created, slowing down the decomposition reaction and allowing chlorous acid (HClO) to be maintained for a long period of time. ２The solution can be prepared by a method that allows it to be stably maintained in water. These methods may involve adding an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt, either individually or in combination with two or more of them, to the aqueous solution. The TAL of aqueous solution A containing any one or more of the inorganic acid, inorganic acid salt, organic acid, or organic acid salt, either individually or in combination with two or more of them, is 20 to 2000, where TAL is determined by the titration volume of 0.1 N-HCl from an initial pH of 11.0 or less to pH 4.

[0073] Examples of chlorous acid water preparations that may be used in this disclosure include "Care for Hand," "Care for Hands Profree," "Care for Fresh," "Outlock Super," "New Outlock SP," "Care Forpis Profree," "Care for No. 3," "Care for Norobarrier Plus," "Care for No. 15," "Chloruscare 8," "Chloruscare 10," "Microlassun," "Chlorous Acid N Barrier," "Microlassun R," and "Microlassun UP," all manufactured by Sankei Co., Ltd.

[0074] The chlorine peroxide radical (ClOO•) used in this disclosure can be produced by contacting an excess amount of hydrogen ions with a solution containing a chlorine oxide having a portion containing two or more oxygen atoms for every one chlorine atom. The excess amount can be determined by the increase in the maximum absorption region at 354 nm in the UV spectrum. The concentration at which an increase in absorbance at a wavelength of 354 nm is first observed can be determined to be the lower limit for the generation of chlorine peroxide radicals. It is important that the amount of hydrogen ions is in excess of the chlorine oxide. We have found that by adding an excess amount of hydrogen ions, chlorine peroxide radicals, which are peroxide radicals, are generated from the chlorine oxide. Because there is an excess of hydrogen ions, the pH can be less than 3, for example, less than 2.5, less than 2.3, 2.0 or less, 1.5 or less, 10 or less, etc. The reaction may be carried out at room temperature in air. In the case of chlorine oxides containing more than two oxygen atoms per chlorine atom (e.g., 2.5, 3, 3.5, or 4) as raw materials, such as chloric acid or perchloric acid, chlorine peroxide radicals can be generated by making the amount of hydrogen ions in excess of the chlorine oxide. Although we do not wish to be bound by theory, the presence of the generated chlorine peroxide radicals can be confirmed by ESR.

[0075] In one embodiment of the present disclosure, the chlorine oxide is chlorine dioxide, chlorine dioxide gas, aqueous chlorine dioxide, stabilized chlorine dioxide (aqueous chlorine dioxide), chlorous acid, chlorite, chlorite ion, chloric acid, chlorate, chlorate ion, perchloric acid, perchlorate, and / or perchlorate ion.

[0076] In one embodiment of this disclosure, the chlorine oxide is an aqueous solution. Using an aqueous solution is convenient for handling and relatively easy to generate chlorine peroxide radicals, making it a desirable configuration.

[0077] In one embodiment of the present disclosure, the step of contacting the hydrogen ions includes adding an acid. In one embodiment of the present disclosure, the acid is a GRAS acid. GRAS acids are generally considered safe substances and may be useful in safely producing and using chlorine peroxide radicals.

[0078] In one embodiment of the present disclosure, the step of contacting the hydrogen ions is H ＋ This includes using a type ion exchange resin. ＋ The ion exchange resin can be any type that provides hydrogen ions. ＋ The ion exchange resin may be added directly to the chlorine oxide as a powder. Alternatively, the chlorine oxide may be passed through a column containing the ion exchange resin.

[0079] In one embodiment of the present disclosure, the chlorine peroxide radical is present in an aqueous solution. The chlorine peroxide radical may be stable in an aqueous solution.

[0080] In one aspect of this disclosure, a composition comprising a chlorine peroxide radical is provided, preferably, an aqueous solution comprising a chlorine peroxide radical is provided. In the aqueous solution containing a chlorine peroxide radical of this disclosure, the chlorine peroxide radical can be present stably for a long period of time, for example, 24 hours, 7 days, or more than one month.

[0081] In one embodiment of the present disclosure, the chlorine peroxide radical exists as an active ingredient in a disinfectant. As described above, chlorine peroxide radicals can exist stably for a long period of time in aqueous solution, for example, for 24 hours, 7 days, or more than one month. Therefore, in the present disclosure, the composition of the present disclosure can be provided as a disinfectant that is effective for a long period of time.

[0082] (Problems in comparing and evaluating the antimicrobial effects of chlorous acid water and sodium hypochlorite) One problem in comparing and evaluating the antimicrobial effects of chlorous acid water and sodium hypochlorite is that chlorine oxide concentrations are expressed as both available chlorine concentration and free chlorine, and the antimicrobial effect depends on free chlorine, which is the source of oxidizing power. While the relationship between free chlorine and available chlorine concentration is approximately 1:1 for sodium hypochlorite, the relationship between available chlorine concentration and free chlorine is not the same for chlorous acid water as it is for sodium hypochlorite. Therefore, when comparing the bactericidal power of both agents on the same playing field, it is necessary to compare them using oxidizing power, that is, free chlorine, which represents the antimicrobial effect, rather than available chlorine concentration.

[0083] The oxidizing power of chlorine oxide chemicals is generally determined using colorimetric methods such as the DPD method or the TMB method. However, unlike sodium hypochlorite, there is no standard for measuring the free chlorine content of chlorous acid water. Therefore, a calibration curve is created by setting the oxidizing power of sodium hypochlorite (as Cl) at 1 mg / L as 1. Note that oxidizing power can be expressed in terms of free chlorine (as Cl), and when comparing using the same free chlorine content, the free chlorine (as Cl) of sodium hypochlorite is generated from Cl radicals, while the free chlorine of chlorous acid water is HClO. ２ Since it is the source of the emission, evaluating it using the same standards would make comparison difficult. Therefore, we calculate it using the same oxidizing power as sodium hypochlorite, where 1 = 1 mg / L of free chlorine (as Cl), and use the same standards to compare and evaluate it on the same playing field as sodium hypochlorite.

[0084] For measuring free chlorine (as Cl), a buffer solution and DPD indicator are added to the sample, and the absorbance is measured at a wavelength of 510 nm using a spectrophotometer. In the presence of organic matter, free chlorine (as Cl) is measured at a wavelength of 655 nm using TMB reagent, and the concentration is determined from the measured value. Furthermore, for the bactericidal effect confirmation test, the free chlorine (as Cl) of the test agent is prepared using the DPD method, each agent is brought into contact with a bacterial solution containing organic matter, and after a certain period of time, it is neutralized with sodium thiosulfate, and the number of surviving bacteria in this neutralized solution is confirmed.

[0085]

[0086] Furthermore, references such as scientific literature, patents, and patent applications cited herein are incorporated herein by reference to the same extent as if they were specifically described herein.

[0087] The present disclosure has been described above with reference to preferred embodiments for ease of understanding. The present disclosure will now be described based on examples, but the above description and the following examples are provided for illustrative purposes only and not to limit the present invention. Accordingly, the scope of the present invention is not limited to the embodiments or examples specifically described herein, but is limited only by the claims.

[0088] (Method for Quantitative Determination of Chlorous Acid Water) Precisely weigh approximately 5 g of this product, add water to make exactly 500 ml, and prepare the sample solution. Precisely weigh 20 ml of the sample solution, put it into an iodine flask, add 10 ml of sulfuric acid (1 → 10), then add 1 g of potassium iodide, immediately stopper the flask and shake well. Add 5 ml of potassium iodide solution to the top of the iodine flask and leave it in the dark for 15 minutes. Next, loosen the stopper and pour in the potassium iodide solution, immediately stopper the flask and shake well, then titrate the liberated iodine with 0.1 mol / L sodium thiosulfate (5 ml of starch solution as indicator). However, the starch reagent should be added when the solution turns pale yellow near the endpoint, and the endpoint should be when the blue color of the solution disappears. Perform a blank test separately and correct the result. 1 ml of 0.1 mol / L sodium thiosulfate solution = 1.711 mg HClO ２ ).

[0089] (Manufacturing Example) The chlorous acid solution preparation used in the following examples was manufactured as follows. In this specification, chlorous acid solution may be abbreviated as "chlorous acid solution," but they are synonymous.

[0090] Analysis table of components of chlorous acid water

[0091]

[0092] Using this chlorous acid solution, a chlorous acid solution preparation was manufactured based on the following formulation.

[0093]

[0094]

[0095] Based on the above preparation method, the "chlorous acid water preparation made with chlorous acid water" was prepared, and the concentration of "chlorous acid water" was measured based on the above "quantitative method for chlorous acid water". Chlorous acid water for each example was then prepared using a buffer solution (phosphate buffer solution containing dipotassium hydrogen phosphate and potassium dihydrogen phosphate) that was prepared to achieve the free chlorine concentration described in each example.

[0096] Chlorous acid water was prepared using the buffering agent described above, according to the preparation method described.

[0097] The active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), was prepared as described in WO2022 / 239801.

[0098] GB chlorine dioxide water is chlorine dioxide that meets the National Standard for Chlorine Dioxide Disinfectants (GB26366-2010) of the People's Republic of China.

[0099] (Example 1: Confirmation test to investigate a long-term storage method for chlorine peroxide radical solution (ClOO•))

[0100] 1) Background: High-concentration chlorine peroxide radical (ClOO•) solutions, even during refrigerated storage, undergo molecularization to stabilize the chlorine peroxide radicals (ClOO•) in the solution, allowing the cyclic reaction to proceed smoothly. See Figure 1, and Tables 1A, 1B, Figures 2-1, and 2-2, which show a significant decrease in "free chlorine concentration (assuming Cl=35.45)" with respect to the porosity (low packing rate) in the container. Therefore, there was no way to stabilize these radicals in the solution for a long period, making long-term storage impossible. Thus, we explored a long-term storage method that would stabilize this high-concentration chlorine peroxide radical (ClOO•) solution in its liquid state for a long period, enabling reuse (inuse) and allowing this high-concentration chlorine peroxide (ClOO•) solution to be distributed.

[0101]

[0102]

[0103] 2) Objective: This study was conducted with the aim of exploring and establishing a long-term storage method that would allow high-concentration chlorine peroxide (ClOO•) solutions to remain stable in liquid form for extended periods, enabling their reuse (in use) and their eventual distribution.

[0104] 3) Test Method: Exploratory test on long-term storage methods (freezing methods) for high-concentration chlorine peroxide radical (ClOO•) solutions (liquids).

[0105] Under the conditions shown in Table 1C below, chlorine peroxide radical (ClOO•) solution was filled into glass bottles and stored at various temperature ranges. Subsequently, the free chlorine concentration (assuming Cl=35.45) (*1) and the content (assuming chlorous acid (HClO2=68.46)) (*2) were measured over time.

[0106] *1: The "free chlorine concentration (assuming Cl=35.45)" was measured by the amount of radicals obtained by the DPD method and expressed as free available chlorine (FAC). *2: The "content (assuming chlorous acid (HClO2=68.46))" was measured by converting the total chlorine amount (TC) obtained by iodine reduction titration to the concentration of chlorous acid (HClO2).

[0107] Discussion: We examined the changes in the chemical quality over time when chlorine peroxide radical (ClOO•) solution was stored under refrigeration (10°C) and under freezing (-20°C). As a result, it was found that the sample stored under freezing (-20°C or below) showed almost no change (no decrease) in the free chlorine concentration (assuming Cl=35.45) and content (assuming chlorous acid (HClO2=68.46)) for 60 days, maintaining the same chemical quality as on the day of preparation. Moreover, when stored under freezing (-20°C), the chemical quality of the radical solution was not affected by the void space (packing density) in the storage container. Under refrigerated storage, the chemical quality of the radical solution is greatly affected by the packing density.

[0108] From the above, it has been found that high-concentration chlorine peroxide radical (ClOO•) solutions can be stored for extended periods under frozen conditions (-20°C or below), maintaining the same chemical quality as the initial product (D+0) while remaining stable for a long time. This storage method allows for the distribution of these peroxide radical (ClOO•) solutions to the market, and the resulting social significance is immeasurable.

[0109] (Example 2: Confirmation test to establish a method for storing and using the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) that was stored in a reserve tank after using the required amount, and then using the stored active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) when needed.)

[0110] <Confirmation of the degree of deterioration (change) of the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) when stored frozen ('free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)')'), confirmation of the degree of deterioration (change) after thawing, and confirmation of the change over time in the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) when stored frozen for a long period of time> Tests were conducted to confirm whether the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) can be stored for a long period of time and made usable by removing oxygen (O2) from the voids in the storage tank and replacing it with inert gases (nitrogen gas and carbon dioxide gas). As a result, it was found that in order to preserve the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) for a long period of time while maintaining its chemical quality (free chlorine concentration (assuming Cl=35.45) and content (assuming chlorous acid (HClO2=68.46))), it is preferable to satisfy as many of the following three conditions as possible: (a) ensuring that oxygen (O2) is not dissolved in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•); (b) minimizing voids in the storage container as much as possible; and (c) preventing the escape of chlorine dioxide gas generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (sealing the container).

[0111] Therefore, as a method to prevent the generation of chlorine dioxide gas from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), instead of storing the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in the refrigerator (2-8°C), the following occurs: [i] The movement of water molecules is slowed down (their kinetic energy is reduced), which reduces the efficiency of the reaction (contact) between chlorine peroxide radicals (ClOO•) and the reaction (contact) between chlorine peroxide radicals (ClOO•) and oxygen (O2) (or other substances) in the liquid in which they are dissolved. [ii] The movement of the chlorine peroxide radical (ClOO•) itself is slowed down (their kinetic energy is reduced), which makes it more difficult for the radicals in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) to react with each other, suppressing the reaction that turns them into chlorine dioxide and gasifies.

[0112] By taking advantage of the two benefits mentioned above, if it becomes possible to store the remaining active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) while maintaining its chemical quality (free chlorine concentration (assuming Cl=35.45) and content (assuming chlorous acid (HClO2=68.46))), then all of the remaining active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) can be stored frozen and thawed and used as needed.

[0113] Therefore, we investigated whether the chemical quality of the active chlorous acid molecule = chlorine peroxide radical (ClOO•) (as free chlorine concentration (assuming Cl=35.45) and content (assuming chlorous acid (HClO2=68.46))) could be maintained, and whether the degree of degradation (change) at that time would remain within an acceptable range, by using the required amount of the active chlorous acid molecule = chlorine peroxide radical (ClOO•) stored in the reserve tank, storing the remaining active chlorous acid molecule = chlorine peroxide radical (ClOO•) under freezing conditions (▲-20℃) (freezer), and thawing it before use when needed. Specifically, we conducted tests to confirm the following items and .

[0114] Confirmation of whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (changes) when frozen (▲-20℃) and then thawed. This includes the free chlorine concentration (assuming Cl=35.45), the content (assuming chlorous acid (HClO2=68.46)), and the pH.

[0115] When freezing the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), concerns have been raised about the increase in the amount of oxygen (O2) that can be dissolved in the liquid, and the occurrence of a concentration gradient during thawing. Therefore, storing the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), frozen (-20°C) and thawing it for use when needed may lead to a deterioration (change) in the chemical quality of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•). Therefore, to confirm whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) at 100% and 50% filling rates deteriorates (changes) when frozen (▲-20℃) and then thawed in the refrigerator (2-8℃), we froze (▲-20℃) and then thawed (▲-20℃) the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) at 100% and 50% filling rates. After freezing, the sample is moved to a refrigerator (2-8°C) for 24 hours to thaw. Once completely thawed, its chemical quality is checked. The decrease in the amount and rate of decrease in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) before and after freezing (assuming Cl=35.45) and the content (assuming chlorous acid (HClO2=68.46)), as well as the pH, are checked (compared). This test is conducted to determine how much the chemical quality deteriorates (changes) after freezing, and whether that deterioration (change) remains within an acceptable range. In this test, the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) stored in a refrigerator (2-8°C) at 100% filling rate is set as the Blank group. If the chemical quality is maintained at a level higher than or equivalent to that of the Blank group, it is considered within an acceptable range.

[0116] Confirmation of changes over time in the chemical quality (free chlorine concentration (assuming Cl=35.45), content (assuming chlorous acid (HClO2=68.46)), and pH) of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after freezing (▲-20℃) and long-term storage of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0117] By freezing (-20°C) the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), and storing them, we took advantage of the benefits described in [i] and [ii] above. To determine how long and to what extent the chemical quality of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), ('free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46)'), and 'pH') can maintain its initial chemical quality (D+0), we conducted tests to confirm the changes over time and whether these changes remained within acceptable limits. These tests were then compared.

[0118] The above two tests will be conducted, and based on the results of test , it will be determined how much the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (changes) compared to the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) that was stored under refrigeration at 100% capacity, even after freezing (▲-20℃) and thawing ('free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)'), and whether that deterioration (change) is within an acceptable range. Furthermore, based on the results of test , we will examine how much the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (changes) when frozen (▲-20℃) and stored for a long period of time compared to the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) that was stored under refrigeration at 100% filling rate, and how well the initial (D+0) chemical quality can be maintained. By comparing these findings, we will determine whether the deterioration (change) is within an acceptable range.

[0119] ○In order to confirm whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) ('free chlorine concentration (assuming Cl=35.45)' and 'content (as chlorous acid (HClO2=68.46)')') of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after freezing and thawing will be maintained at the initial level, first, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after freezing and thawing ('free chlorine concentration (assuming Cl=35.45)' and 'content (as chlorous acid (HClO2=68.46)')) The purpose is to confirm the degree of deterioration (change) of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) when frozen and stored for a long period of time, and to confirm the degree of change over time in the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (free chlorine concentration (Cl=35.45)), content (chlorous acid (HClO2=68.46)), and pH).

[0120] ○Method 1. Dilute GB chlorine dioxide solution five times with deionized water to obtain a five-fold diluted solution.

[0121] 2. The ion exchange resin is pre-swelled with ion-exchanged water, and this is used as the ion exchange resin.

[0122] 3. Add the ion exchange resin and a 5-fold diluted solution of GB chlorine dioxide water to a glass container so that the solid-to-liquid ratio is 1:5.

[0123] 4. After adding the ingredients, leave them undisturbed in a refrigerated state (below 10°C) for at least 24 hours.

[0124] 5. After standing, if it can be confirmed that the contents of the solution have become the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (UV spectrum: single maximum absorption region at 346-361 nm, pH: 2.0 or less), then measure the 'content' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (assuming chlorous acid (HClO2=68.46)), 'free chlorine concentration (assuming Cl=35.45)', 'pH', and 'UV spectrum'. This is considered the initial state (D+0).

[0125] 6. Fill 100 mL medium bottles with the prepared active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), to the desired filling density. Store in the refrigerator if refrigerated (2-8°C) or in the freezer if frozen (-20°C). However, filling should be done in a glove box purged with nitrogen (N2) gas.

[0126] 7. For samples stored frozen (▲-20℃), ensure they are completely thawed in the refrigerator before measuring their quality (content (as chlorite (HClO2=68.46)), free chlorine concentration (as Cl=35.45)), pH, and UV spectrum).

[0127] *1) In all test sections, the filling process will be carried out in a glove box purged with nitrogen (N2) gas, and after sealing, the product will be stored in a refrigerator (2-8°C) or freezer (-20°C). *2) When storing frozen, leave the product in the freezer (-20°C) for at least 24 hours, and once it is confirmed that it is frozen, transfer it to a refrigerator (2-8°C) and thaw it over 24 hours.

[0128] ○Results ・Exam

[0129] • Exam

[0130] ○ (Test ) ・Blank section: Test section in which the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was stored refrigerated (2-8°C) at 100% filling rate. ・Test section I-(α): Test section in which the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was stored frozen (▲-20°C) for 24 hours at 100% filling rate, then, after confirming that it was frozen, was transferred to a refrigerator and thawed over 24 hours. ・Test section I-(β): Test section in which the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was stored frozen (▲-20°C) for 24 hours at 50% filling rate, then, after confirming that it was frozen, was transferred to a refrigerator and thawed over 24 hours (the void (space) was replaced with nitrogen (N2) gas).

[0131] The results of the three test groups in Test are reflected in the table and graph in the results column. First, [1] the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46))' of each test group were compared to consider whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) does not deteriorate (change) even after freezing and thawing, and whether such deterioration (change) remains within an acceptable range. Next, [2] the contents of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after freezing and thawing were considered to change compared to the case of refrigeration. In this test, for the Test group that was frozen and thawed, it was confirmed that a concentration gradient occurred after thawing, so it was measured after inversion mixing to homogenize it.

[0132] [1] Comparison of the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46))' of each test group before storage (D+0) and after storage (D+2).

[0133] Table 2A summarizes the remaining percentages of 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' after storage (D+2) for each test group, using the pre-storage (D+0) value as the baseline (100%). Values ​​higher than those of the Blank group were considered within the acceptable range, while values ​​lower than those of the Blank group were deemed outside the acceptable range. First, looking at the 'free chlorine concentration (assuming Cl=35.45)', it can be seen that the Blank group and Test group I-(α)(β) maintained a 'free chlorine concentration (assuming Cl=35.45)' at or above the pre-storage (D+0) value after storage (D+2). These results indicate that the free chlorine concentration (assuming Cl=35.45) of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), remains within an acceptable range (at or above the level of the active molecular species of chlorous acid stored under refrigeration) even after freezing and thawing.

[0134] Next, looking at the "content (as chlorite (HClO2 = 68.46))", the remaining percentage of the Blank sample after storage (D+0) was approximately 98%, indicating a degradation (change) of about 2%. If this is considered within the acceptable range, then Test sample I-(α) falls within the acceptable range, while Test sample I-(β) falls outside the acceptable range.

[0135] From the above results, it was found that even if the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is frozen and thawed, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) hardly deteriorates (changes) (remains within the acceptable range). However, in Test section I-(β) with a filling rate of 50%, it was found that the 'content (as chlorous acid (HClO2=68.46)') decreases (outside the acceptable range) upon freezing and thawing. As for the reason for this, in this test, after confirming that it was frozen, it was moved to a refrigerator (2-8°C) and thawed for 24 hours. It was found that Test section I-(β) with a filling rate of 50% thawed in about 4 hours. As a result, for the remaining approximately 20 hours, the conditions were the same as when it was stored in the refrigerator with a filling rate of 50%, and it is thought that the chlorine peroxide radical (ClOO•) gasified during this time, which is the reason why it exceeded the acceptable range.

[0136] *3) The value before storage (D+0) was used as the baseline for the survival rate (100%), and a value higher than the survival rate of the Blank section (D+2) was judged to be within the acceptable range.

[0137] No significant differences were observed between the contents of the Blank sample, which was stored in the refrigerator, and the Test sample, which was frozen and then thawed.

[0138] The chemical quality observed in Test Section I-(β) ("Content (as chlorite (HClO2=68.46)")) has not deteriorated (changed) overall.

[0139] Furthermore, regarding 'pH', one of the chemical qualities of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), as shown in the results table above, it can be seen that the pH value of Test group I-(α)(β), which was frozen and thawed, is slightly lower than that of the Blank group. However, given that there is no difference in the chemical qualities ('free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46))') between Test group I-(α) and the Blank group, this change in 'pH' value is considered to be within an acceptable range.

[0140] From the results of the above test , it was found that even when the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is frozen and thawed, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) remains within an acceptable range (hardly deteriorates or changes). Considering this, it is quite possible to confirm whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (changes) and, if so, to what extent, while the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is frozen and stored, by comparing the difference in the values ​​of "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" obtained before storage (D+0) and after D+30 obtained in test .

[0141] However, the results of test suggest that when freezing and thawing the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), (1) if the packing density is low (there are many voids), a reaction occurs in which the chlorine peroxide radical (ClOO•) gasifies after thawing. (This is not due to the freezing and thawing itself, but rather because it was stored with voids.) (2) After thawing, a concentration gradient occurs in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). (3) If the product is frozen and thawed multiple times, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) may be affected.

[0142] The above three concerns were raised. Regarding (1), it is believed that this can be adequately prevented by promptly utilizing the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after thawing. Regarding (2), it was found that homogenization by inversion mixing (stirring in the field) is preferable. However, regarding (3), assuming an operational method in the field where the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) that has been frozen and stored is thawed and used, and then refreezed and stored, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) ('free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46)'), and 'pH') may be affected by repeating the freezing and thawing operation multiple times. However, whether this method of operation is necessary depends on the amount of active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) produced in one batch and the amount used at one time. If half of the total amount is used at once, then freezing and storing it, and using it after thawing, will leave almost no amount remaining, so it is highly likely that there will be no need to freeze it again, and it is thought that this method of operation will allow for complete use. Therefore, based on the above method of operation, an additional confirmation test will be conducted to compare the chemical quality of active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) used up by performing the freezing and thawing operation once (when 50% is extracted at one time) and active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) used up by performing the freezing and thawing operation three times (when 30% is extracted at one time and this is repeated three times).

[0143] From the above, it was found that in Test of this study, the effect of freezing and thawing on the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was negligible and within acceptable limits. Test will be continued as is. Furthermore, in order to confirm the effect on the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) when the freezing and thawing operation, which is a concern in this study, is performed multiple times, a test will be conducted in Example 4.

[0144] ○ (D+30) ・Blank section: Test section in which the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was stored refrigerated (2-8℃) at 100% filling rate. ・Test section I-(α): Test section in which the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was stored frozen (▲-20℃) at 100% filling rate until the period of D+30, then, after confirming that it was frozen, it was moved to a refrigerator and thawed over 24 hours. ・Test section I-(β): Test section in which the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was stored frozen (▲-20℃) at 50% filling rate until the period of D+30, then, after confirming that it was frozen, it was moved to a refrigerator and thawed over 24 hours (the void (space) was replaced with nitrogen (N2) gas).

[0145] [3] Comparison of 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' for each test group (D+30)

[0146] Table 2B summarizes the remaining percentages of "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" after 30 days of storage for each test group, using the pre-storage (D+0) value as the baseline (100%). First, as shown in Table 2B, Test group I-(α)(β), which was stored frozen, maintained higher values ​​for both "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" than Blank group, which was stored refrigerated. This indicates that even after 30 days of frozen storage, the values ​​remained within the acceptable range (at least equivalent to the active molecular species of chlorous acid stored under refrigeration = chlorine peroxide radical (ClOO•)). Furthermore, regarding "free chlorine concentration (assuming Cl=35.45)," it remained at or above the pre-storage (D+0) value, indicating that it did not decrease at all when stored frozen.

[0147] Furthermore, regarding the "content (as chlorous acid (HClO2=68.46))", it appears to have decreased slightly, but it is unlikely that only the "content (as chlorous acid (HClO2=68.46))" would decrease while the "free chlorine concentration (as Cl=35.45)" has not decreased at all. Moreover, considering that the results obtained in test show that the "content (as chlorous acid (HClO2=68.46))" decreases by about 2-5% just from the freezing and thawing process, it is thought that the "content (as chlorous acid (HClO2=68.46))" hardly decreased during the 30 days of storage. Therefore, it is judged to be an error between each sample that occurs during filling, or a measurement error.

[0148] *3) The value before storage (D+0) was used as the baseline for the survival rate (100%), and a value higher than the survival rate of the Blank section (D+30) was judged to be within the acceptable range.

[0149] During storage in the freezer, the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), remain largely unchanged.

[0150] Next, comparing the pH values ​​of each test group from the results table above, the pH was 1.20 before storage (D+0), while the Blank group was pH 0.93 and the Test group I-(α)(β) was pH 1.03. Furthermore, considering that the lower the pH, the more the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (the decomposition reaction of radical active species including chlorine peroxide radical progresses), the pH values ​​indicate that freezing and storing the product suppresses the deterioration (changes) occurring in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0151] From the above, the results up to D+30 show that the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) ('free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46)' and 'pH') and contents) remained almost unchanged from before storage (D+0) during frozen storage. This indicates that there is a good possibility of maintaining the same level of quality as before storage for a long period of time if stored frozen.

[0152] 〇 (D+60) Using the initial state (D+0) as the baseline (100%), Figure 6 summarizes the remaining percentage of 'free chlorine concentration (assuming Cl=35.45)' and Figure 7 summarizes the remaining percentage of 'content (assuming chlorous acid (HClO2=68.46))' for each test group up to D+60. First, examining Figure 6, it was found that the Test groups-(α)(β), which were stored frozen, maintained a higher value of 'free chlorine concentration (assuming Cl=35.45)' than the Blank group, which was stored refrigerated, and furthermore, it was found that they maintained a value equivalent to that before storage (D+0). Next, examining Figure 7, similarly, it was found that the Test groups-(α)(β) maintained a higher value of 'content (assuming chlorous acid (HClO2=68.46))' than the Blank group. This suggests that even if the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), are stored frozen for 60 days, their chemical quality remains within acceptable limits (same as or better than that of chlorous acid stored under refrigeration).

[0153] Regarding the change over time in the "content (as chlorous acid (HClO2=68.46))" of Test Group-(α)(β), it appears to have decreased compared to before storage (D+0). However, considering the effects of freeze-thaw cycles, concentration gradients, and variability between samples, Test Group-(α) (100% filling rate), which has a remaining rate of approximately 90%, can be said to be almost unchanged from its state before storage (D+0), and is considered to have been stored while maintaining a sufficiently consistent level of chemical quality. On the other hand, the "content (as chlorous acid (HClO2=68.46))" of Test Group-(β) (50% filling rate) is even lower. From this, it can be concluded that at D+60, it is almost unchanged from its state before storage (D+0), and maintains a consistent level of chemical quality.

[0154] Furthermore, regarding pH, it was found that the values ​​of the Test group-(α)(β) were almost the same as the values ​​before storage (D+0) when compared to the Blank group. From this, it can be concluded that by freezing, not only the chemical quality but also the contents within the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) can be preserved with almost no change.

[0155] Therefore, it is necessary to consider freeze-thaw methods, but the results of this test clearly show that the active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), does not deteriorate (change) much when stored frozen compared to when stored refrigerated, in terms of chemical quality (free chlorine concentration (assuming Cl=35.45), content (assuming chlorous acid (HClO2=68.46)), and pH).

[0156] 〇 (D+90) Using the initial state (D+0) as the baseline (100%), the remaining percentage of 'free chlorine concentration (assuming Cl=35.45)' up to D+90 for each test group is summarized in Figure 8, and the remaining percentage of 'content (assuming chlorous acid (HClO2=68.46))' is summarized in Figure 54. First, looking at Figure 8, it was found that, similar to the results for D+60, all Test groups (α: 100% filling rate) and (β: 50% filling rate) that were stored frozen up to D+90 were within the acceptable range, and that they maintained the same 'free chlorine concentration (assuming Cl=35.45)' as before storage (D+0). Furthermore, since no difference was observed in the time-dependent change in the free chlorine concentration (assuming Cl=35.45) between Test sections (α) and (β), it can be seen that the freezing storage method not only suppresses the reaction with chlorine peroxide radicals (or other substances), but also suppresses the effects of voids during storage (molecular (gasification) of chlorine peroxide radicals).

[0157] Furthermore, regarding the "content (as chlorous acid (HClO2=68.46))", it was clear that both Test Group-(α) and(β) were within the acceptable range. However, compared to the value before storage (D+0), a trend was observed in all cases where the "content (as chlorous acid (HClO2=68.46))" gradually decreased (approximately 5% for every 30 D+). Comparing the remaining percentage of the "content (as chlorous acid (HClO2=68.46))" of the active molecular species = chlorine peroxide radical (ClOO•) (Figure 54) of chlorous acid stored at -80°C for a period of D+30 with that of Test Group-(α) (Figure 54) in the test (-20°C), it can be seen that the active molecular species = chlorine peroxide radical (ClOO•) of chlorous acid frozen and stored at -80°C maintained a higher value. From this, it can be inferred that at a temperature of -20°C, the vibration of water molecules does not completely stop, and this slight vibration of water molecules causes a reaction in which chlorine oxides (ions and molecules measured by the KI method) that are active under acidic conditions other than radicals are gradually oxidized. As a result, the 'free chlorine concentration (assuming Cl=35.45)' which reflects the radical concentration does not decrease, and only the 'content (assuming chlorous acid (HClO2=68.46))', which is an indicator of the total chlorine amount, decreases.

[0158] Freezing is a storage method that preserves the chemical quality of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), and also preserves the contents of the active molecular species of chlorous acid (ClOO•) with minimal change. Furthermore, this freezing method is highly effective for chlorine peroxide radicals, the main component of the active molecular species of chlorous acid (ClOO•).

[0159] From the above results, it was clearly found that the active molecular species of chlorous acid, chlorine peroxide radicals (ClOO•), can be stored in a frozen state rather than a refrigerated state, without significantly degrading (changing) the chemical quality of the active molecular species of chlorous acid, chlorine peroxide radicals (ClOO•). Furthermore, regarding the "free chlorine concentration (assuming Cl=35.45)", it was maintained at the same value as before storage (D+0) up to the period of D+90, indicating that it is usable at this level. However, judging from the results for "content (assuming chlorous acid (HClO2=68.46))", a temperature of -20℃ is insufficient to maintain the same chemical quality as before storage. It is thought that by further lowering the storage temperature and slowing down the vibration of water molecules, the "content (assuming chlorous acid (HClO2=68.46))" value as before storage (D+0) can be maintained.

[0160] Furthermore, based on the results of this test, we believe that the reason why only the "content (as chlorous acid (HClO2 = 68.46))" decreased is because chlorine oxides other than radicals that can be measured by the KI method (for example, unreacted products derived from chlorine raw materials) were gradually oxidized.

[0161] (Example 3: A test to confirm whether removing oxygen (O2) from the voids in the storage tank and replacing it with inert gases (nitrogen gas and carbon dioxide gas) allows the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) to be stored and used for a long period of time.)

[0162] ○Background: In order to establish a system in which the active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), is manufactured and stored in a refrigerator (in a light-shielded state), and when necessary, this stored active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), is used to manufacture chlorous acid water and chlorous acid water preparations, the first step was to introduce a manufacturing plant for the active molecular species of chlorous acid, chlorine peroxide radical (ClOO•).

[0163] However, when manufacturing the formulation, if only the required amount of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is extracted and used, the amount of voids in the storage tank for the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) increases. The more voids there are (especially when the voids exceed 50%), the faster the quality of the stored active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (a decrease in the 'free chlorine concentration (assuming Cl=35.45)', which is an indicator of oxidizing power; a decrease in the 'content (assuming chlorous acid (HClO2=68.46))', which is an indicator of safety; and a change in 'pH', which represents the properties of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•)). This indicates that these voids have some effect on the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). Therefore, when considering the operation of using chlorine peroxide radicals (ClOO•), which are the active species of chlorous acid, by storing them in a storage tank and using them little by little, it is necessary to solve the problem of what methods and equipment should be set up for storage (stockpiling), that is, what measures (methods) should be taken to minimize the impact on the active species of chlorous acid (ClOO•) that is created by gradually using the active species of chlorous acid (ClOO•) in the storage tank, so that the chlorine peroxide radicals (ClOO•), which are the active species of chlorous acid, can be stored for a longer period of time and used up completely.

[0164] Based on the above, in order to clarify the factors that degrade the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), previous experiments suggested that the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is stable under degassing conditions (removal of oxygen (O2) from the voids). From this, the possibility arose that the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) could be stored for a long period of time by removing oxygen (O2) from the voids in the storage tank. However, the test system (conditions, etc.) used at that time was insufficient, so we thought it necessary to establish a more rigorous and reproducible test system (conditions, etc.) to confirm whether it is truly possible to stabilize (delay degradation) the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) by removing oxygen (O2). Therefore, we prepared a vacuum glove box that can create an environment free of oxygen (O2) and conduct tests under that environment. We then checked whether the quality of the active molecular species of chlorous acid stored in the glove box—chlorine peroxide radicals (ClOO•)—was stabilized (deterioration was delayed) by replacing the oxygen (O2) in the void with an inert gas (nitrogen (N2) gas or carbon dioxide (CO2) gas).

[0165] Furthermore, regarding the environment with oxygen (O2) removed from the void, this test will be conducted under conditions where the oxygen concentration inside the vacuum glove box is approximately 0.1%, based on the knowledge that the minimum oxygen concentration controlled when products are filled using vacuum filling is less than 1%.

[0166] Based on the above, we will find a method to minimize the impact of voids that gradually form when the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in the storage tank is used little by little, and to confirm whether the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) will remain stable (deterioration delayed) for a long period of time if the oxygen (O2) in the voids is removed and replaced with an inert gas (nitrogen (N2) gas or carbon dioxide (CO2) gas), we will conduct a storage stability test of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in a glove box with the voids replaced with an inert gas (nitrogen (N2) gas or carbon dioxide (CO2) gas).

[0167] The following four test sections will be used to verify the following three items to <C>. The verification items for this test will be as follows: • Blank section: Active molecular species of chlorous acid stored after being filled to 100% capacity (assuming no voids and low degradation) = chlorine peroxide radical (ClOO•) • Test section I-(α): Active molecular species of chlorous acid stored after being filled to 10-90% capacity (voids replaced with nitrogen gas (N2)) = chlorine peroxide radical (ClOO•) • Test section I-(β): Active molecular species of chlorous acid stored after being filled to 10-90% capacity (voids replaced with carbon dioxide gas (CO2)) = chlorine peroxide radical (ClOO•) • Control section: Active molecular species of chlorous acid stored after being filled to 10-90% capacity (voids contain air: oxygen, so it is assumed to be easily oxidized) = chlorine peroxide radical (ClOO•)

[0168] Comparison over time: The measurement results for the Blank section and Test section I-(α) and (β) are plotted, and the length of time that the Test section maintains the same level of quality as the Blank section (a certain standard is set, and the free chlorine concentration (Cl=35.45) or higher is confirmed and compared for each filling rate.

[0169] Comparison based on filling density: The measurement results for the Blank section and Test section I-(α) and (β) are plotted, and it is confirmed which of the three patterns ((1) stable, (2) proportional, (3) rapidly decreasing) the free chlorine concentration (assuming Cl=35.45) follows according to the filling density of the Test section.

[0170] <C> Comparison with the Control Group In the cases of patterns (2) and (3), the measurement results of the Test group and the Control group are plotted to compare whether the quality of the active molecular species of chlorous acid in the Test group = chlorine peroxide radical (ClOO•) (free chlorine concentration (assuming Cl=35.45)) is close to that of the Blank group or the Control group. ○ Method 1. Dilute GB chlorine dioxide water five times with deionized water to make this a five-fold diluted solution of GB chlorine dioxide water. 2. Measure the 'free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46))', 'pH', and 'UV spectrum' of the GB chlorine dioxide water. 3. Swell the ion exchange resin in advance with deionized water to make this the ion exchange resin. 4. In a glass container, add the five-fold diluted solution of GB chlorine dioxide water to the ion exchange resin so that the solid:liquid ratio is 5 for every 1 part ion exchange resin. 5. After adding the solution, leave it standing for at least 12 hours in a refrigerated state (below 10°C). 6. After standing, if it can be confirmed that the contents have become the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (UV spectrum: having a single maximum absorption region at 346-361 nm, pH: 1.5 or higher and less than 2.0), measure the free chlorine concentration (assuming Cl=35.45), content (assuming chlorous acid (HClO2=68.46)), pH, acidity (T.AC), and UV spectrum of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). 8. Prepared chlorous acid active molecular species = chlorine peroxide radical (ClOO•) are packed into containers without any gaps (100% packing rate) to form the Blank group. Packed to 10% to 90% and using a vacuum glove box to replace the gaps with inert gas (nitrogen (N2) gas, carbon dioxide (CO2) gas) to achieve an oxygen concentration of approximately 0.1% are designated as Test Group I-(α) and Test Group I-(β), respectively. Packed to 10% to 90% and filled with air is designated as the Control group. Afterwards, the containers are stored upside down in a refrigerated state (below 10°C) for up to 90 days (D+30, D+60, D+90).Furthermore, the quality of the active molecular species of chlorous acid remaining after filling on the day = chlorine peroxide radical (ClOO•) is measured ('free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46)'), 'pH', 'acidity (T.AC)', and 'UV spectrum'), and this is defined as D+0. 9. The quality of each stored sample (D+30, D+60, D+90) is measured ('free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46)'), 'pH', and 'UV spectrum'). *1) The quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) from (1) to (9) in the Blank section and Test section I-(α) and (β) is confirmed. If they are at the same level, it is considered that removing oxygen (O2) (replacing it with an inert gas) is an effective method for long-term storage of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), which is the purpose of this test. *2) If the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) from (1) to (9) in Test section I-(α) and (β) is worse than that of the Blank section, the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in Test section I-(α) and (β) and the Control section (e.g., Test section I-(α)-(1) and Control section-(1)) with the same filling density will be compared to determine the extent to which factors other than oxygen (O2) are affecting the quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). When comparing the Test section and the Control section, in order to more clearly show the difference in quality, the residual rate (an indicator showing how well the free chlorine concentration (assuming Cl=35.45) in the Test section or Control section is maintained compared to the Blank section) will be calculated and compared for consideration.

[0171] ○Results [A] Comparison of the change over time of 'free chlorine concentration (assuming Cl=35.45)' for each filling rate in the Blank group (100% filling rate) and Test group I-(α)(β) [C] Comparison of the change over time of 'free chlorine concentration (assuming Cl=35.45)' for each filling rate in the Control group (Air) and Test group I-(α)(β) [B] Comparison of 'free chlorine concentration (assuming Cl=35.45)' for the Blank group (100% filling rate) and each filling rate (10-90%) during each storage period (D+30, 60, 90)

[0172] ○Measurement results *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100 *3) Remaining rate (%) = Free chlorine concentration at each filling rate (D+30, D+60, D+90) / Free chlorine concentration in the Blank section (D+30, D+60, D+90) × 100

[0173] ○ (D+30) Blank section: Active molecular species of chlorous acid stored after being filled to full capacity (100% filling rate) = chlorine peroxide radical (ClOO•) Test section I-(α): Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with nitrogen (N2) gas = chlorine peroxide radical (ClOO•) Test section I-(β): Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with carbon dioxide (CO2) gas = chlorine peroxide radical (ClOO•) Control section: Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with air (O2) = chlorine peroxide radical (ClOO•) The results up to D+30 for the above four test sections are reflected in the table. First, [A] the change in free chlorine concentration (assuming Cl=35.45) over time was examined for each filling density. Next, [B] the behavior of free chlorine concentration (assuming Cl=35.45) for each filling density in Test section I-(α)(β) and the Control section was examined and discussed. Furthermore, [C] the values ​​of free chlorine concentration (assuming Cl=35.45) in Test section I-(α)(β) and the Control section were compared and discussed.

[0174] [A] Changes over time in 'free chlorine concentration (assuming Cl=35.45)' for each filling rate in Blank and Test I-(α)(β) As for the changes over time for each filling rate (10-90%) in each test group, it was found that at D+30, the 'free chlorine concentration (assuming Cl=35.45)' decreased (was consumed) in all test groups, including the Blank group (see results). Next, it can be seen that the Control group and Test I-(α)(β), with filling rates of 30% or more, maintained the same 'free chlorine concentration (assuming Cl=35.45)' as the Blank group (100% filling rate). From this, it was found that the decrease in 'free chlorine concentration (assuming Cl=35.45)' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) due to voids (spaces) in the container begins to occur when the filling rate falls below 30%. Furthermore, as shown in Figures 10-1 to 10-5, in containers with a filling rate below 20%, the free chlorine concentration (assuming Cl=35.45) in Test containers I-(α)(β) decreased (was consumed) more than in the Blank container. However, the Control container decreased (was consumed) even more. From this, it can be inferred that in containers with a filling rate below 20%, the gas density in the void decreases, and the container becomes filled with gas generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). Therefore, even if oxygen (O2) in the void inside the container is removed beforehand and replaced with inert gas (nitrogen (N2) gas, carbon dioxide (CO2)), the free chlorine concentration (assuming Cl=35.45) in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is gradually consumed by the newly generated gas. However, this test revealed that substitution slows down the decrease in free chlorine concentration (assuming Cl=35.45) compared to not substitution (making it less likely to be consumed). While there was no significant difference in free chlorine concentration (assuming Cl=35.45) between Test I-(α) and Test I-(β) across different filling rates, only the 10% filling rate product showed that Test I-(α) > Test I-(β), suggesting that nitrogen (N2) gas may be more effective at slowing down the decrease in free chlorine concentration (assuming Cl=35.45) (making it less likely to be consumed).

[0175] [B] Comparison of 'Free Chlorine Concentration (assuming Cl=35.45)' between the Blank section (100% filling rate) and each filling rate (10-90%) We confirmed how the 'Free Chlorine Concentration (assuming Cl=35.45)' of each test section behaves differently depending on the filling rate. First, as shown in Figure 11, all test sections maintain the same 'Free Chlorine Concentration (assuming Cl=35.45)' as the Blank section (100% filling rate) up to a filling rate of 30%. However, it was found that the concentration rapidly decreases from the filling rate below 20%, and as discussed in [A], even if oxygen (O2) in the void is removed beforehand, it is suggested that the decrease in the 'Free Chlorine Concentration (assuming Cl=35.45)' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) may progress further from the filling rate below 30% (when a certain gas density is reached). Furthermore, as can be seen from the results table above, the "free chlorine concentration (assuming Cl=35.45)" decreased (was consumed) compared to the Blank group. Looking at the remaining percentage, which indicates how much remains, the test group with the greatest consumption of "free chlorine concentration (assuming Cl=35.45)" (Control group, 10% filling rate) showed a decrease of more than 30% compared to the Blank group. On the other hand, for all test groups with a filling rate exceeding 30%, the remaining percentage remained at around 90%. This indicates that if the product is stored in a sealed state with a filling rate of 30% or more, the "free chlorine concentration (assuming Cl=35.45)" of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) will hardly be consumed for 30 days.

[0176] [C] Comparison of the change over time in 'free chlorine concentration (assuming Cl=35.45)' for each filling rate in the Control (Air) and Test I-(α)(β) groups. From the results in [B], it can be seen that for low filling rates (filling rate of 20% or less), Blank group > Test group I-(α)(β), and even if oxygen is removed in advance and inert gas (nitrogen (N2) gas, carbon dioxide (CO2)) is filled, the consumption of the 'free chlorine concentration (assuming Cl=35.45)' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) cannot be suppressed. Next, the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46))' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in the Control group and Test group I-(α)(β) were checked and compared. First, looking at Figure 11, for samples with a filling density below 30%, the "free chlorine concentration (assuming Cl=35.45)" in Test section I-(α)(β) remained at a higher concentration than in the Control section. As discussed in [A], it was found that removing oxygen (O2) from the voids beforehand and replacing it with an inert gas (nitrogen (N2) gas) makes it easier to maintain a high "free chlorine concentration (assuming Cl=35.45)" than not replacing it. Furthermore, looking at the results table above, the "content (assuming chlorous acid (HClO2=68.46))" was also maintained at a higher level in Test section I-(α)(β) than in the Control section for samples with a filling density below 30%, suggesting that oxygen (O2) may affect the "content (assuming chlorous acid (HClO2=68.46))".

[0177] Summarizing the test results up to D+30, (1) In all test groups, including the Blank group, the "free chlorine concentration (assuming Cl=35.45)" was depleted. (2) In Test groups I-(α)(β) and the Control group, the depletion of the "free chlorine concentration (assuming Cl=35.45)" of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) was more pronounced in those with a filling rate below 20-30%. (3) In low-filling-rate products (filling rate of 20% or less), replacing the voids with nitrogen (N2) gas beforehand makes the "free chlorine concentration (assuming Cl=35.45)" less depleted than if it were not replaced. As a result, there is a higher possibility of maintaining a high concentration. However, even if oxygen (O2) in the voids is removed, if there is a certain amount of void (when the gas density becomes low), the "free chlorine concentration (assuming Cl=35.45)" will be depleted due to the influence of some factor. Furthermore, in the case of low-filling-rate products (filling rate of 20% or less), even if oxygen (O2) is removed beforehand, the reason why the "free chlorine concentration (assuming Cl=35.45)" of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is consumed is thought to be due to the significant influence (susceptibility) of chlorine dioxide gas generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), in addition to oxygen (O2). For this reason, the decrease in "content (assuming chlorous acid (HClO2=68.46))" per 1 mL of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (assuming chlorous acid (HClO2=68.46)) was confirmed in mg for the [D] Blank group (filling rate 100%) and the Test group I-(α) (filling rate 10% to 90%). This allowed us to examine, in particular, what differences in quality were observed in products with low fill rates (20% or less) compared to the Blank group (100% fill rate), other than the 'free chlorine concentration (assuming Cl=35.45)' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0178] [D] Comparison of the decrease (mg) in 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' per 1 mL of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). First, since the liquid volume (mL) of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) differs between each filling rate, we checked how much the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' decreased up to D+30 when converted to per 1 mL of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), and summarized this in Figure 24. Note that both are converted as chlorous acid (HClO2=68.46). As shown in Figure 24, compared to the Blank section (100% filling rate) (Figure 24, circle), the decrease in the amount of "free chlorine concentration (assuming Cl=35.45)" per 1 mL of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (assuming chlorous acid (HClO2=68.46)) increases more rapidly in products with a low filling rate (20% or less), similar to [B]. However, the decrease in "content (assuming chlorous acid (HClO2=68.46))" compared to the Blank section (100% filling rate) (Figure 24, triangle) can be seen to begin increasing when the filling rate falls below 40%. The decrease (consumption) of "free chlorine concentration (assuming Cl=35.45)" is due to the consumption of chlorine peroxide radicals (ClOO•) under some influence, and this definitely occurs when the filling rate falls below 20% (voids are 80% or more). However, given that the "content (as chlorous acid (HClO2=68.46))" is lower in products with higher filling rates (30% to 40%), we believe that the decrease in total chlorine (chlorous acid) is due to consumption (oxidation) under different influences than the decrease in "free chlorine concentration (as Cl=35.45)".

[0179] Here, regarding the main mechanism by which the free chlorine concentration (assuming Cl=35.45) and content (assuming chlorous acid (HClO2=68.46)) of the active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), decrease (consume), the chlorine dioxide gas (ClO2↑) generated from the active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), is a stable gaseous form of the chlorine peroxide radical (ClOO•). This is considered to be important knowledge not only for the active molecular species of chlorous acid, chlorine peroxide radical (ClOO•), but also for long-term storage of the free chlorine concentration (assuming Cl=35.45).

[0180] Furthermore, when examining the decrease in "free chlorine concentration (assuming Cl=35.45)" (mg) for products with a 10% filling rate and a 20% filling rate (Figure 24), it was found that the 10% filling rate product generated approximately twice as much chlorine dioxide gas as the 20% filling rate product, with chlorine peroxide radicals (ClOO•) being more stable. In other words, it can be inferred that the more voids (space) there are in the container, the more chlorine dioxide gas is generated, and this increased generation leads to a depletion of "free chlorine concentration (assuming Cl=35.45)".

[0181] Furthermore, from the results of [D], even if oxygen (O2) is removed beforehand, the reason why the 'free chlorine concentration (assuming Cl=35.45)' is consumed in low-filling-rate (filling rate of 20% or less) products is that, compared to high-filling-rate products, the density of gas in the voids inside the container is lower in low-filling-rate (filling rate of 20% or less) products. A large amount of chlorine dioxide gas (ClO2↑) is required until this density difference reaches a certain pressure, and the chlorine peroxide radicals (ClOO•) are stabilized into chlorine dioxide gas (ClO2↑), causing the chlorine peroxide radicals (ClOO•) to disappear, i.e., the 'free chlorine concentration (assuming Cl=35.45)' is consumed.

[0182] On the other hand, the reason why the "content (as chlorous acid (HClO2=68.46))" gradually decreases from below a 40% filling rate is thought to be due to oxidation by some substance. Given that oxygen (O2) has been removed beforehand, it is thought that the chlorine dioxide molecules (ClO2) in the active molecular species of chlorous acid = chlorine peroxide radicals (ClOO•) (which have not been gasified (ClO2↑) because the gas density in the void is sufficiently high) or the oxygen (O2) produced by the decomposition of chlorine dioxide gas (ClO2↑) consumes (oxidizes) the "content (as chlorous acid (HClO2=68.46))".

[0183] ○ (D+60) Blank section: Active molecular species of chlorous acid stored after being filled to full capacity (100% filling rate) = chlorine peroxide radical (ClOO•) Test section I-(α): Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with nitrogen (N2) gas = chlorine peroxide radical (ClOO•) Test section I-(β): Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with carbon dioxide (CO2) gas = chlorine peroxide radical (ClOO•) Control section: Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with air (O2) = chlorine peroxide radical (ClOO•) The results up to D+60 for the above four test sections are reflected in the table. First, [A] the changes over time in "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" for each filling rate were examined. Next, [B] the behavior of "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" for each filling rate in Test group I-(α)(β) and the Control group was examined and discussed. Furthermore, [C] the values ​​of "free chlorine concentration (assuming Cl=35.45)" in Test group I-(α)(β) and the Control group were compared and discussed.

[0184] [A] The graphs showing the time course of 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' for each filling rate in the Blank and Test I-(α)(β) groups, show that for all test groups (Test I-(α), Test I-(β), and Control), the decrease in 'free chlorine concentration (assuming Cl=35.45)' from D+30 to D+60 is smaller (less) than the decrease from D+0 to D+30. A similar trend is also observed for 'content (assuming chlorous acid (HClO2=68.46))'. Next, Table 3A shows the results of comparing the remaining percentage of "free chlorine concentration (assuming Cl=35.45)" (with the Blank section at D+0 set to 100%) for each filling percentage (10-90%) in the Blank section (100% filling percentage) during the period from D+0 to D+60. Similarly, Table 3B shows the results of comparing the remaining percentage of "content (assuming chlorite (HClO2=68.46))". Looking at Table 3A, as mentioned above, the remaining percentage of "free chlorine concentration (assuming Cl=35.45)" at D+30 is about 70% (50% for low-filling-percentage products) for all filling percentages, while the remaining percentage at D+60 is about 60% (40% for low-filling-percentage products). This shows that the concentration only decreased by about 10% during the period from D+30 to D+60. However, on the other hand, it can be seen that the number of products with a filling rate lower than the Blank product's retention rate in each test group during each period (D+30, D+60) (Table 3A) increases as the storage period lengthens in every test group (products with a higher filling rate have a lower retention rate than the Blank product). Furthermore, at D+60, the Control group (Air) has the lowest retention rate among the products with a higher filling rate (Table 3A). From this, it can be seen that the presence of oxygen (O2) in the container's voids (space) causes the free chlorine concentration (assuming Cl=35.45) to decrease as the storage period lengthens.Next, looking at Table 3B, the remaining content (as chlorous acid (HClO2=68.46)) at D+30 for each test group was approximately 70% (40% for low-filling products), while the remaining content at D+60 was approximately 60% (40% for low-filling products). This shows that the change from D+30 to D+60 was only about 0-10%. However, for the 10% filling product, the content (as chlorous acid (HClO2=68.46)) was higher at D+60 than at D+30 in all test groups, but this is clearly considered to be a measurement error. Therefore, it is considered that there was almost no change (decrease) from D+30 to D+60. However, on the other hand, in each test group, it can be seen that for the filled products (in red in Table 3B) where the remaining content (as chlorous acid (HClO2=68.46)) is lower than in the Blank group, the values ​​for both D+30 and D+60 remain unchanged. From this, it appears that oxygen (O2) is influencing not the content (as chlorous acid (HClO2=68.46)) but rather the free chlorine concentration (as Cl=35.45) ≈ chlorine peroxide radical (ClOO•).

[0185] * Red text indicates a lower percentage of remaining free chlorine concentration (assuming Cl=35.45) compared to the Blank section (green text). *Red text: Lower percentage of residual content (as chlorous acid (HClO2=68.46)) compared to the Blank section (green text).

[0186] [B] Behavior of 'Free chlorine concentration (assuming Cl=35.45)' and 'Content (assuming chlorous acid (HClO2=68.46)' for each filling rate in Test section I-(α)(β) and Control section. Figure 12 shows the behavior of 'Free chlorine concentration (assuming Cl=35.45)' for each filling rate in D+60, and Figure 25 shows the behavior of 'Content (assuming chlorous acid (HClO2=68.46)'). First, looking at Figure 12, unlike D+30, which maintained a 'Free chlorine concentration (assuming Cl=35.45)' at a similar level to the Blank section (100% filling rate) up to a filling rate of 30%, in D+60, it can be seen that in all test sections, the 'Free chlorine concentration (assuming Cl=35.45)' becomes lower than the Blank section (100% filling rate) when the filling rate falls below 40%. Furthermore, when the filling rate fell below 40%, the free chlorine concentration (assuming Cl=35.45) remained higher in Test group I-(α)(β) than in the Control group. This result reaffirmed that, similar to the results of D+30, the presence of oxygen (O2) in the container's voids (spaces) leads to a decrease (consumption) of the free chlorine concentration (assuming Cl=35.45).

[0187] Next, looking at Figure 25, we can see that in all test groups, similar to the results for D+30, even at D+60, if the filling rate is 50% or higher, the "content (as chlorous acid (HClO2=68.46))" remains at the same level as the Blank group (filling rate 100%). Furthermore, when the filling rate falls below 20%, the "content (as chlorous acid (HClO2=68.46))" in the Control group decreases rapidly, but the Test group I-(α)(β) maintains a higher concentration. This shows that by removing oxygen (O2), the decrease (consumption) of "content (as chlorous acid (HClO2=68.46))" can be suppressed even in low-filling rate products (filling rate of 20% or less). Furthermore, while the 10% fill rate sample in the Control group clearly maintains a high value for "content (as chlorous acid (HClO2=68.46))", the reliability of the "content (as chlorous acid (HClO2=68.46))" value is considered low when compared with other measurement results, including "free chlorine concentration (as Cl=35.45)". Therefore, it is treated as an outlier.

[0188] [C] Comparing the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' for each filling rate in the Control and Test I-(α)(β) sections, Figures 12 and 25 show that the low-filling-rate products (filling rate of 20% or less) in each test section (Test I-(α)(N2), Test I-(β)(CO2), and Control (Air)) are consistent with the D+30 results, with both the 'free chlorine concentration (assuming Cl=35.45)' and the 'content (assuming chlorous acid (HClO2=68.46)' being lower than the Blank section (filling rate of 100%). This indicates that even if oxygen (O2) in the void (space) is removed beforehand, these decreases cannot be suppressed in a sealed state. Furthermore, in low-filling-rate products (filling rate of 20% or less), the Test sections I-(α)(N2) and I-(β)(CO2), where oxygen (O2) is absent, maintain higher concentrations of both free chlorine (assuming Cl=35.45) and chlorous acid (HClO2=68.46) than the Control section (Air), where oxygen (O2) is present in the void (space). This suggests that the method (strategy) of removing oxygen (O2) is quite effective when adopted as a method of gradually using the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) while preserving the remainder, which is consistent with the results of D+30. However, looking at Table 3B, when comparing the remaining content (as chlorite (HClO2=68.46)) of Test section I-(α)(N2) and Test section I-(β)(CO2), it can be seen that Test section I-(β)(CO2) has a lower content than the Blank section (100% filling rate) even with a higher filling rate. Nitrogen (N2) gas is preferred as the inert gas used for gas displacement.

[0189] Considering the above results together with the results of [A], the reason why the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46))' decreased during the period from D+0 to D+30 is thought to be that, until the voids (spaces) inside the container reached a certain density, the amount of chlorine peroxide radicals (ClOO•) corresponding to each filling rate gasified, generating chlorine dioxide gas (ClO2↑). The reason why the levels decreased during the period from D+30 to D+60 is thought to be due to chlorite ions (ClO2 - ) and chlorine peroxide radicals (ClOO•) are affected by chlorine dioxide gas (ClO2↑) and chloride ions (Cl - This is thought to be because the reaction proceeded in which it was decomposed into (ClO2). In other words, when there is a void (space) inside the container, chlorine peroxide radicals (ClOO•) stabilize and accumulate in the void (space) as chlorine dioxide gas (ClO2↑) until the void (space) reaches a certain density. However, after a certain density is reached, chloride ions (Cl - As it decomposes, the free chlorine concentration (assuming Cl=35.45) decreases, which is thought to cause a decrease in the content (as chlorous acid (HClO2=68.46)). However, since the latter decomposition reaction proceeds more slowly, the decrease in both the free chlorine concentration (assuming Cl=35.45) and the content (as chlorous acid (HClO2=68.46)) is thought to be smaller (less) during the period from D+30 to D+60. Furthermore, during the period from D+30 to D+60, the "content (as chlorous acid (HClO2=68.46))" of low-filling-rate products (filling rate of 20% or less) hardly decreased (Table 3B), but on the other hand, the "free chlorine concentration (as Cl=35.45)" decreased slightly (Table 3A). This suggests that the decomposition products of chlorine dioxide gas (O2 or Cl2) are influencing chlorine peroxide radicals (ClOO•) (by removing electrons and stabilizing them into chlorine dioxide molecules).

[0190] Therefore, looking at the comparison results of [A], [B], and [C], we believe that in low-filling products, the quality degradation mechanism of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is as shown in Figure 26, and we also believe that the part indicated by the red arrow is the reaction that is most promoted in each period. However, in the period from D+0 to D+30, until the density in the void (space) inside the container becomes constant, chlorine peroxide radical (ClOO•) is gasified and chlorine dioxide gas (ClO2↑) is generated and accumulates in the void (space). Subsequently, this chlorine dioxide gas (ClO2↑) is decomposed by some factor (influence), producing decomposition products (O2, or Cl2), which oxidize the chlorine peroxide radical (ClOO•) in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), thereby decreasing the 'free chlorine concentration (assuming Cl=35.45)', and as a result, the 'content (assuming chlorous acid (HClO2=68.46))' also decreases. Next, during the period from D+30 to D+60, the density within the voids (spaces) inside the container is constant, so it is thought that almost no chlorine dioxide gas is generated, and chlorine peroxide radicals (ClOO•) are produced by chloride ions (Cl - ) and chlorate ions (ClO3 -Although it decomposes into chlorite, this reaction proceeds slowly, so we believe that both the decrease in "free chlorine concentration (assuming Cl=35.45)" and the decrease in "content (assuming chlorous acid (HClO2=68.46))" will be gradual. However, even in this state, the decomposition products of chlorine dioxide gas constantly oxidize chlorine peroxide radicals (ClOO•), and as a result, we believe that the "free chlorine concentration (assuming Cl=35.45)" will decrease even in products with a filling rate of 30% or more, as shown in Table 3A. Furthermore, in this case, we believe that the "content (assuming chlorous acid (HClO2=68.46))" becomes too low, making it impossible to supply enough chlorine peroxide radicals (ClOO•) to maintain the "free chlorine concentration (assuming Cl=35.45)," and that this is the reason why the "content (assuming chlorous acid (HClO2=68.46))" has hardly decreased. From this, it seems that in order to preserve the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), for a longer period of time, it would be very effective to remove the chlorine dioxide gas (ClO2↑) that accumulates as the size of the void (space) increases, since the oxygen (O2) in the void (space) has been replaced with nitrogen (N2) gas in advance, thereby preventing the generation of decomposition products by ClO2↑.

[0191] ○ (D+90) Blank section: Active molecular species of chlorous acid stored after being filled to full capacity (100% filling rate) = chlorine peroxide radical (ClOO•) Test section I-(α): Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with nitrogen (N2) gas = chlorine peroxide radical (ClOO•) Test section I-(β): Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with carbon dioxide (CO2) gas = chlorine peroxide radical (ClOO•) Control section: Active molecular species of chlorous acid stored after being filled at various filling rates (10-90% filling rate) and the voids replaced with air (O2) = chlorine peroxide radical (ClOO•) The results up to D+90 for the above four test sections are reflected in the graph and table. First, [A] the changes over time in "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" for each filling rate were examined. Next, [B] the behavior of "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" for each filling rate in Test Group I-(α)(β) and the Control Group was examined and discussed. Furthermore, [C] the values ​​of "free chlorine concentration (assuming Cl=35.45)" in Test Group I-(α) and Test Group I-(β) were compared and discussed.

[0192] [A] The graphs showing the time course of 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' for each filling rate in the Blank and Test I-(α)(β) groups. Looking at the time course of 'free chlorine concentration (assuming Cl=35.45)' for each filling rate (10-90%) in each test group (Test I-(α)(β) and Control group), the decrease (slope of the graph) from D+60 to D+90 was quite small for all filling rates, and this was also the case for the Blank group. From this, it was found that the 'free chlorine concentration (assuming Cl=35.45)' did not decrease significantly in any of the test groups during the period from D+60 to D+90. Naturally, a similar trend was observed for the "content (as chlorous acid (HClO2=68.46))," and it can be seen that in the period from D+60 to D+90, both the "free chlorine concentration (as Cl=35.45)" and the "content (as chlorous acid (HClO2=68.46))" remained almost unchanged compared to the period from D+0 to D+30, and even from D+30 to D+60. Next, Table 3C shows the results of comparing the remaining rates of "free chlorine concentration (as Cl=35.45)" (with the D+0 Blank section set to 100%) for each filling rate (10-90%) in the Blank section (100% filling rate) and each test section from D+0 to D+90. Similarly, Table 3D shows the results of comparing the remaining rates of "content (as chlorous acid (HClO2=68.46))." Table 3C shows that in Test group I-(α)(β), even with higher filler ratios, the remaining rate of free chlorine concentration (assuming Cl=35.45) is lower than in the Blank group between D+30 and D+90. However, even at D+90, if the filler ratio is 70% or higher, the free chlorine concentration (assuming Cl=35.45) remains the same as in the Blank group. In contrast, in the Control group, at D+90, all filler ratios (10% to 90%) show a lower remaining rate than in the Blank group.From the above, as described in the reports from D+30 to D+60, when the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is stored in a sealed container for a long period of time, if oxygen (O2) is present in the void (space) inside the container, both the 'content' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (assuming chlorous acid (HClO2 = 68.46)) and the 'free chlorine concentration (assuming Cl = 35.45)' will decrease further. Therefore, by removing the oxygen (O2) in this void (space) and replacing it with an inert gas (nitrogen (N2) gas, carbon dioxide (CO2) gas), it has now been confirmed that the 'free chlorine concentration (assuming Cl = 35.45)' can be maintained (stored) at a high value.

[0193] Next, looking at Table 3D, in all test groups from D+30 to D+90, if the filling rate was 60% or higher, the "content (as chlorous acid (HClO2=68.46))" value was maintained at the same level as the Blank group. This indicates that the "content (as chlorous acid (HClO2=68.46))" is more significantly affected by the amount (rate) of voids (space) in the container, and that if stored below a certain filling rate (50-60%), it decreases significantly more than the Blank group, regardless of the number of days elapsed. In other words, in order to maintain (store) a high value of "content (as chlorous acid (HClO2=68.46))", it is necessary to keep the amount (rate) above a certain level without falling below a certain filling rate.

[0194] If the remaining percentage (%) of 'free chlorine concentration (assuming Cl=35.45)' is lower than that of the Blank group (however, if it is 99%, no difference will be observed and it will be excluded).

[0195] *This applies when the remaining percentage (%) of "content (as chlorite (HClO2 = 68.46)" is lower than that of the Blank group (however, if it is 99%, no difference is observed and it will be excluded).

[0196] [B] Behavior of 'Free chlorine concentration (assuming Cl=35.45)' and 'Content (assuming chlorous acid (HClO2=68.46)' for each filling rate in Test Group I-(α)(β) and Control Group Figure 13 shows the behavior of 'Free chlorine concentration (assuming Cl=35.45)' for each filling rate in D+90, and Figure 28 shows the behavior of 'Content (assuming chlorous acid (HClO2=68.46)'). First, looking at Figure 13, as described in the reports up to D+30 and D+60, in low-filling-rate products (filling rate of 50% or less), the 'Free chlorine concentration (assuming Cl=35.45)' is lower than in the Blank Group, but the 'Free chlorine concentration (assuming Cl=35.45)' is maintained at a higher value in Test Group I-(α)(β) than in the Control Group, which is consistent with previous results. However, at D+90, for the first time, it was found that even with high-filling-rate products (filling rate of 60% or more), the free chlorine concentration (assuming Cl=35.45) was maintained at a higher value in Test section I-(α)(β). From this, it was found that the longer the storage period, the lower the free chlorine concentration (assuming Cl=35.45) of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) begins to be due to the presence of oxygen (O2) in the voids (spaces) inside the container, even with high-filling-rate products. Therefore, the method of removing oxygen (O2) from the voids (spaces) and replacing it with an inert gas (nitrogen (N2) gas) is effective not only for low-filling-rate products but also for high-filling-rate products. It became clear that when storing the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), except for 100%-filling-rate products, oxygen (O2) from the voids (spaces) should be removed and replaced with an inert gas each time the contents are removed. On the other hand, Figure 28 shows that the "content (as chlorite (HClO2=68.46))" tends to gradually decrease in all test groups when the filling rate falls below 50%, compared to the Blank group, which is consistent with the results of the above-mentioned reports (D+30, D+60).However, in high-filling-rate products (filling rate of 60% or more), no significant difference was observed between Test group I-(α)(β) and the Control group. As described in [A], unlike the 'free chlorine concentration (assuming Cl=35.45)', it is clear that the 'content (assuming chlorous acid (HClO2=68.46)') decreases sharply once the amount of voids (space) exceeds a certain level (50%). Therefore, it was found that if a high filling rate (70% or more) is maintained, the 'content (assuming chlorous acid (HClO2=68.46)') hardly decreases. Based on the above, we believe that when the filling rate falls below 50%, the "content (as chlorous acid (HClO2 = 68.46))" decreases, and therefore the "free chlorine concentration (as Cl = 35.45)" also decreases. On the other hand, at a filling rate of 60% or more (Control group), the "free chlorine concentration (as Cl = 35.45)" decreases due to the influence of oxygen (O2).

[0197] [C] Comparison of 'Free chlorine concentration (assuming Cl=35.45)' and 'Content (assuming chlorous acid (HClO2=68.46)' for each filling density in Test Group I-(α) and Test Group I-(β) As described in [A] above, in addition to low-filling density products, Test Group I-(α)(β) maintained a higher value for 'free chlorine concentration (assuming Cl=35.45)' than the Control Group, even in high-filling density products. This clearly indicates that oxygen (O2) is one of the factors that lowers 'free chlorine concentration (assuming Cl=35.45)'. From this, it is clear that it is very important to manage the storage of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) so that it does not come into contact with oxygen (O2). On the other hand, in order to confirm which inert gas (nitrogen (N2) gas, carbon dioxide (CO2) gas) is better to use, we compared them in Table 3C, but as a result no clear difference was found between the two.

[0198] From the above, summarizing the measurement results from D+30 to D+90, (1) During the period from D+0 to D+30, chlorine dioxide gas is generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) until the void (space) inside the container reaches a certain density. However, since this chlorine dioxide gas is formed when chlorine peroxide radical (ClOO•) stabilizes and becomes chlorine dioxide and then gasifies, especially in low-filling-rate products, compared to 100%-filling-rate products (Blank section), the 'free chlorine concentration (assuming Cl=35.45)' ≈ chlorine peroxide radical (ClOO•) decreases rapidly, and to compensate for this decrease, the 'content (assuming chlorous acid (HClO2=68.46))' ≈ total chlorine amount also decreases accordingly. (2) When storing the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in a sealed container for a long period of time, it was found that there is a very high possibility that the free chlorine concentration (assuming Cl=35.45) can be maintained at a high level if the oxygen (O2) in the void (space) inside the container is removed and replaced with an inert gas (nitrogen (N2) gas, carbon dioxide (CO2) gas). (3) In the period from D+30 to D+90, compared with the 100% filled product (Blank), a decrease in the free chlorine concentration (assuming Cl=35.45) is observed even in the higher filled product of Test section I-(α) from which oxygen (O2) has been removed. However, on the other hand, it was found that the content (assuming chlorous acid (HClO2=68.46)) begins to decrease when the filling rate falls below a certain level (50%), regardless of the type of gas in the void (space). This raises concerns that the decomposition products of chlorine dioxide gas accumulating in the void (space) may be affecting the 'free chlorine concentration (assuming Cl=35.45)' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0199] Based on the results of this test, it was found that when the filling rate is low (especially below 20%), the free chlorine concentration (assuming Cl=35.45) and content (assuming chlorous acid (HClO2=68.46)) decrease rapidly even when replaced with an inert gas. Therefore, the best course of action is to completely use up the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) in the storage tank. However, if this is not possible, the tank should be transferred to a smaller capacity tank and the voids (spaces) inside the container should be replaced with an inert gas, or the tank should be stored at a filling rate above a certain level, with the voids (spaces) inside the container being replaced with an inert gas, while managing the remaining amount (rate). Conversely, this also means that the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) can be stored for a certain period of time. Furthermore, it was found that one way to store the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), for extended periods is to add new active molecular species of chlorous acid each time it is used, thereby maintaining a 100% fill rate at all times. However, this method presents the problem of making lot management difficult.

[0200] Furthermore, as described in (4), when storing the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) for a long period of time, there is concern that the decomposition products of chlorine dioxide gas generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) may be affecting the 'free chlorine concentration (assuming Cl=35.45)' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0201] Based on the above, the management method after filling a storage container with 100% of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is as follows: (I) Limit the amount used to approximately 30%, always leaving at least 70% of the container filled, and store the container while replacing any voids (spaces) in the container created by using the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) with an inert gas, minimizing contact with oxygen (O2) as much as possible. (If the filling rate falls below 70%, either transfer the entire amount to a smaller container or use up the remaining amount.)

[0202] (II) A method in which a small-capacity storage tank is prepared, and each time the remaining amount is used, the oxygen (O2) in the void (space) is immediately removed and replaced with an inert gas before storage (however, if this method is adopted, the possibility of quality deterioration due to the transfer to a different container cannot be denied). It has been found that by taking the above methods (I) to (II), the 'content' of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) (assuming chlorous acid (HClO2=68.46)) and the 'free chlorine concentration (assuming Cl=35.45)' can be maintained (stored) at higher values ​​than when oxygen (O2) is not removed. Another method is to add new active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) each time it is used so that the filling rate is always 100%, although lot management will not be possible. It is considered desirable to allow the chlorine dioxide gas generated in the void (space) inside the container to escape and to constantly replace it with an inert gas during storage.

[0203] Methods for preserving the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), for a longer period include: Preventing the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), from coming into contact with air (O2) during the storage period (by replacing it with an inactivating gas); Minimizing voids (spaces) in the storage container (to prevent the creation of space for chlorine dioxide gas to be generated from the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•); <c> Preventing the release of chlorine dioxide gas generated in the storage tank (container) of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•) (to suppress the amount of chlorine dioxide gas newly generated from the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•));

[0204] It was found that it is preferable to meet these three conditions. However, considering that the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is measured according to the production quantity of chlorous acid water and chlorous acid water preparations and used little by little, it is not possible to completely eliminate the voids in the storage tank for the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) or to completely prevent the leakage of chlorine dioxide gas that accumulates in the storage tank.

[0205] Therefore, as one way to prevent the generation of chlorine dioxide gas from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•), we considered that a very effective method would be to freeze (▲-20℃) the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) itself in order to slow down the reaction between chlorine peroxide radicals (ClOO•) by suppressing the vibration of water. The reason for this is that freezing (▲-20℃) storage slows down the movement of water molecules (reduces their kinetic energy), which reduces the efficiency of the reaction (contact) between chlorine peroxide radicals (ClOO•) and the reaction (contact) between chlorine peroxide radicals (ClOO•) and oxygen (O2) (or other substances) in the liquid in which they are dissolved, compared to refrigeration (2-8℃). [ii] By slowing down the motion of the chlorine peroxide radical (ClOO•) itself (reducing its kinetic energy), the reactive molecular species of chlorous acid = the radicals in the chlorine peroxide radical (ClOO•) become less likely to react with each other, suppressing the reaction that leads to the formation of chlorine dioxide and subsequent gasification.

[0206] For the reasons stated above, if it is possible to store the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), for a long period of time while maintaining the "free chlorine concentration (assuming Cl=35.45)" using this method, then the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), can be used, and the remaining active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), can be stored using this method.

[0207] (Example 4: Additional verification test to establish a method for storing the remaining active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after using the required amount stored in a reserve tank, and for use when needed.) <Confirmation of the effects on the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) ('free chlorine concentration (assuming Cl=35.45)', 'content (assuming chlorous acid (HClO2=68.46)'), and 'pH') when repeatedly frozen and thawed.>

[0208] ○Test Overview In the results of Test of Example 2, it was found that when the storage period was short, the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) of chlorous acid that was frozen and thawed decreased in "content as chlorous acid (HClO2=68.46)" compared to the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) of chlorous acid that was stored under refrigeration. Furthermore, it was suggested that even with frozen storage, the product may be affected by voids when the packing rate is low (packing rate 50%). Therefore, a test will be conducted to confirm to what extent the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) ("free chlorine concentration (as Cl=35.45)", "content (as chlorous acid (HClO2=68.46))", and "pH") is affected by repeating the freezing and thawing operation multiple times, and to what extent it is affected by voids.

[0209] [I. Confirmation of the effect of repeated freeze-thaw cycles on the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•)] We confirmed how much the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is affected when repeated freeze-thaw cycles are performed at a filling rate of 100%.

[0210] ○ Test area

[0211] ○Results

[0212] Using the pre-storage (D+0) value as the baseline (100%), the remaining percentages of "free chlorine concentration (assuming Cl=35.45)" and "content (assuming chlorous acid (HClO2=68.46))" obtained from the results of test group (1) were calculated and summarized in Figure 31. Upon review, it was found that the more freeze-thaw cycles there were, the lower both the "free chlorine concentration (assuming Cl=35.45)" and the "content (assuming chlorous acid (HClO2=68.46))" decreased. Next, when freeze-thaw cycles were repeated 5 times, the "content (assuming chlorous acid (HClO2=68.46))" decreased by approximately 10%. A simple calculation suggests that with each freeze-thaw cycle, the "content (assuming chlorous acid (HClO2=68.46))" decreases by approximately 2%. Furthermore, the results of the above test (Figure 31) also show that the "content (as chlorous acid (HClO2 = 68.46))" decreases by approximately 2% after one freeze-thaw cycle, which is consistent with the results of this test. From the above, it was found that repeated freeze-thaw cycles gradually degrade (change) the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). It is thought that this is because melting begins with the components of higher concentration, and when it is completely melted, a concentration gradient (non-uniform state) is created as a result, increasing the probability of collisions between radicals and thus promoting the decomposition reaction.

[0213] [II. Confirmation of the effects of voids when repeated freeze-thaw cycles are performed under sealed conditions] Next, in order to confirm whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) deteriorates (changes) due to voids during freeze-thaw cycles, we first used a sample with 100% filling density (no voids) and a sample with a void density (fill density) of 50%, and repeatedly subjected them to freeze-thaw cycles under sealed conditions to confirm the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0214] ○ Test area

[0215] ○Results

[0216]

[0217] First, by comparing the Cont group (test group (1)) and test group (2), we aimed to confirm whether repeated freeze-thaw cycles in the presence of voids would degrade (change) the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). To this end, the remaining rate of the 'free chlorine concentration (assuming Cl=35.45)' for each test group was summarized in Figure 36, and the remaining rate of the 'content (assuming chlorous acid (HClO2=68.46))' was summarized in Figure 37. First, looking at Figure 36, although there is some variation, it can be seen that there is no difference in the remaining rate of the 'free chlorine concentration (assuming Cl=35.45)' between the Cont group (test group (1)) and test group (2). Next, looking at Figure 37, although there is similar variation, it can be seen that even after repeated freeze-thaw cycles, there is no significant difference in the remaining rate of the 'content (assuming chlorous acid (HClO2=68.46))' between the two test groups. From the above, it was found that, under sealed conditions with a filling rate of 50% or more, the chemical quality of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), is hardly affected by voids, even with repeated freeze-thaw cycles.

[0218] However, since a lower filling rate results in a shorter time to become liquid, the longer standing time in liquid state after complete melting is a concern. During this time, the decomposition reaction of the radical active species in the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) progresses, generating chlorine dioxide gas. As a result, there was concern that this would lead to a deterioration (change) in the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). However, it was found that if the filling rate is 50% or higher, the effect of repeated freeze-thaw cycles has a greater impact on the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) than the effect of chlorine dioxide gas generated in the voids.

[0219] However, in actual production, the method involves extracting the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), for use as a raw material, and then freezing the remaining liquid. This makes it highly unlikely that the container can always be kept in a sealed state. Furthermore, when used as a raw material, it is always left open, which would allow the generated chlorine dioxide gas (ClO2↑) to escape, potentially leading to further gasification and a deterioration of the chemical quality of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•).

[0220] Furthermore, judging from the results in Figures 36 and 37, the chemical quality of test group (2) and test group (3) ('free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)')') is similar, and it is unlikely that the effect of freeze-thaw cycles is due to thawing time.

[0221] [III. Confirmation of the effect of voids in the operational method of freezing and storing the remaining active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) after use] We had considered that if there were many (large) voids in the container, chlorine dioxide gas would be generated in these voids, and that even if stored frozen, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) would be affected. However, under sealed conditions with a filling rate of 50% or more, no such effect was observed. Therefore, assuming an actual operational method, we confirmed whether the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) would be affected by voids when the remaining liquid was stored while removing the raw material (opening the container).

[0222] ○ Test area ○Results

[0223] Figure 40 summarizes the remaining percentage of "free chlorine concentration (assuming Cl=35.45)" for each test group, and Figure 41 summarizes the remaining percentage of "chlorite content (assuming HClO2=68.46)." Furthermore, when comparing test group (1) as the Cont group to subtract the effects of freeze-thaw cycles, it can be seen that if the number of freeze-thaw cycles is only one, the extracted (opened) test groups (4) and (5) maintain the same "free chlorine concentration (assuming Cl=35.45)" as the Cont group. However, as the number of freeze-thaw cycles and extractions (openings) increases, it was found that the "free chlorine concentration (assuming Cl=35.45)" in test group (5) decreases compared to the Cont group and test group (4). Furthermore, similar to the above, it was found that the "content (as chlorous acid (HClO2=68.46))" decreased in test group (5) as the number of freeze-thaw cycles and sampling (opening) cycles increased. From these results, we consider that in test group (5), in addition to the effects of freeze-thaw cycles, when the raw material is used, it is opened by sampling, and at this time, the chlorine dioxide gas generated in the void is released, causing a deterioration (change) in the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0224] Therefore, it has been found that if chlorite active molecular species = chlorine peroxide radical (ClOO•) with a filling rate of 50% or more is frozen and stored, and then used up after thawing, there will be no effects from air pockets, and it can be used with the same chemical quality as before storage. We believe that this method of operation is quite feasible to implement in the field.

[0225] In summary, the results of this test can be summarized as follows: (1) Each time freeze-thaw cycle is performed, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) ('free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)')' deteriorates (decreases) by a certain amount (about 2% of the total). (Note that the amount of deterioration with one freeze-thaw cycle is small, but the more it is repeated, the more the deterioration progresses (chemical quality decreases), so it is thought that the number of freeze-thaw cycles should be kept to a minimum.) (2) Under sealed conditions, it was found that if the filling rate is 50% or more, the effect of voids during freeze-thaw is almost negligible. However, it was also found that when the container is opened to extract and use the raw material, chlorine dioxide gas generated in the void escapes, and even if it is frozen and stored, the deterioration (change) of the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) cannot be prevented. (Furthermore, it was found that if the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) remaining after use is frozen and stored, and then used up after thawing, it can be used without any problems.)

[0226] [IV. Confirmation of the effect of freezing on the chemical quality of chlorite's active molecular species = chlorine peroxide radical (ClOO•)] Regarding the effect of freeze-thaw cycles, during slow freezing (▲-20°C), substances with higher melting points (water molecules) freeze first, creating a region (concentration gradient) with a high concentration of chlorine peroxide radicals (and other radical active species). During freezing, the probability of collisions between radicals (contact efficiency) increases, and it is thought that decomposition reactions (stabilization) may proceed. Using a deep freezer (▲-80°C), we conducted a test to compare the chemical quality of chlorite's active molecular species = chlorine peroxide radical (ClOO•) rapidly frozen (▲-80°C) and chlorite's active molecular species = chlorine peroxide radical (ClOO•) slowly frozen (▲-20°C) to confirm whether slow freezing (▲-20°C) degrades (changes) the chemical quality of chlorite's active molecular species = chlorine peroxide radical (ClOO•).

[0227] ○ Test area *1) After thawing was complete, the product was mixed by inversion 10 times to return it to a uniform state, and then it was frozen again for storage or measured again.

[0228] ○Results

[0229] ○Discussion (Retest IV) Using the initial test (0 freeze-thaw cycles) as the baseline (100%), the remaining percentage of 'free chlorine concentration (assuming Cl=35.45)' for each test group is summarized in Figure 52, and the remaining percentage of 'content (assuming chlorous acid (HClO2=68.46))' is summarized in Figure 47. Upon examination, it was found that even with repeated freeze-thaw cycles, there was no significant difference in the chemical quality ('free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)')) between the Cont group (▲-20℃) and test group (6) (▲-80℃). This indicates that the effects of freeze-thaw cycles ('decreased content (assuming chlorous acid (HClO2=68.46)')) are present in both test groups. Furthermore, when 'pH' and UV spectrum were examined, no similar differences were observed. From this, we believe that the effect of freeze-thaw cycles is more influenced by the concentration gradient generated during thawing than by the effect during freezing. However, since this effect is very slight, the storage method of the present invention is considered useful for the long-term storage of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•).

[0230] Based on the above results, it is highly likely that the effects of freeze-thaw cycles occur during thawing. However, even from the results of this test, this effect is very slight at the laboratory level (small scale). Therefore, we will first confirm to what extent this effect occurs in actual manufacturing settings (large scale). However, regarding the effect of voids, in follow-up test V, we confirmed whether the remaining chlorous acid active molecular species = chlorine peroxide radical (ClOO•) should be transferred to another small container or used up if the filling rate is low (filling rate of 50% or less).

[0231] [V. Confirmation of suppression of deterioration of the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) by transferring to a small container] The results obtained in Test III suggested that if the remaining active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is at a low filling rate (filling rate of 50% or less), transferring it to another small container and then freezing and storing it may suppress the deterioration (change) of the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). Based on this, a follow-up test was conducted.

[0232] ○ Test area

[0233] 〇Results

[0234] 〇Discussion Using the initial value (D+0) as the baseline (100%), the remaining percentages of the 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46)' for test groups (7) and (8) were summarized in Figure 50. We hypothesized that test group (8), which was transferred to a smaller container, would maintain the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) for a longer period, and conducted the test accordingly. However, no significant difference was observed between the two test groups. From this, it was found that even if the liquid is transferred to a smaller container, if the filling rate is too low (30% or less), it is not possible to suppress the deterioration (change) of the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). However, a problem with this test system is that test group (8) underwent two transfers, and during these transfers, physical factors such as liquid splashing and contact with oxygen (O2) in the air may have caused the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) to deteriorate (change), and as a result, the effect of transferring to a smaller container may have been negated.

[0235] Therefore, we compared the chemical quality of two groups: Group Cont, in which the remaining active molecular species of chlorous acid (ClOO•) was frozen and stored at a low filling rate (10-50%) after only one transfer; and Group Test, in which the same amount of remaining active molecular species of chlorous acid (ClOO•) as in Group Cont was transferred to a small container at a high filling rate (100%), frozen, and stored.

[0236] First, using the pre-storage (D+0) value as the baseline (100%), the remaining percentage of the 'free chlorine concentration (assuming Cl=35.45)' for each filling rate (50%, 30%, and 10%) in the Cont group (no transfer) and the Test group (with transfer) is summarized in Figure 51, and the 'content (assuming chlorous acid (HClO2=68.46))' is summarized in Figure 52. Upon examination, it was found that if the filling rate was 30% or higher, the chemical quality of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) remained unchanged from pre-storage (D+0) even without transfer. However, on the other hand, when the filling rate fell below 30%, the Test group, which had been transferred, had higher 'free chlorine concentration (assuming Cl=35.45)' and 'content (assuming chlorous acid (HClO2=68.46))' than the Cont group, and furthermore, it was clear from this figure that these values ​​remained almost unchanged from pre-storage (D+0). From this, it was found that as long as the product is transferred to a container with a filling rate of at least 30% and then frozen and stored, no deterioration (change) in chemical quality will occur. In addition, the results of test group (8) conducted in supplementary test IV showed that the only change in chemical quality of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), was due to physical factors such as splashing of liquid that occurred when transferring to a small container.

[0237] However, this also means that even if the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), are frozen and stored, if the packing density is low (30% or less), the voids will have an effect, and the same chemical quality as before storage cannot be maintained. It should be noted that freezing the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), minimizes the amount of chlorine dioxide gas generated in the voids. Therefore, the effect of voids at low packing density (30% or less) is not due to the freezing process itself, but rather to the generation of chlorine dioxide gas from the liquid active molecular species of chlorous acid (ClOO•) upon thawing. This (storing at a low packing density under refrigeration) is thought to degrade (change) the chemical quality of the active molecular species of chlorous acid (ClOO•) even in a short period of time, such as within 24 hours.

[0238] Based on the above, the findings from the results of follow-up tests I to V can be summarized as follows: (1) It is preferable to limit the number of freeze-thaw cycles. (The fewer the cycles, the closer the chemical quality to that before storage can be maintained. However, there was no effect from one or two freeze-thaw cycles, and it was within a range that did not cause problems.) (2) Since a concentration gradient occurs during freeze-thaw cycles, it is preferable to homogenize the solution before use. (It is necessary to consider improving the freezing or thawing method to a method that does not cause a concentration gradient.) (3) Even if the remaining active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) is frozen and stored, if the amount of void is too large (filling rate is less than 30%), chlorine dioxide gas will be generated from the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•) during thawing, and will be affected by the void.

[0239] However, if the storage container is changed to ensure a high fill rate (50% or more), storage can be carried out without any problems. (However, when transferring the contents to a different container, risk management such as preventing liquid splashing is necessary.)

[0240] These three points are what I believe should be considered when implementing frozen storage methods in practice.

[0241] If we consider freezing the entire amount of the active molecular species of chlorous acid, namely chlorine peroxide radicals (ClOO•), and distributing it, or if we consider freezing the remaining liquid after use, and then measuring and using the frozen active molecular species of chlorous acid (ClOO•), it is conceivable that the effects of voids would not be present. Furthermore, even if only a small amount of liquid remains, if we transfer it to a container with as little void as possible to ensure a high packing density, store it, and then freeze it, we believe that all of these problems could be solved.

[0242] (Example 5: Comparison of slow freezing and rapid freezing) Regarding the free chlorine concentration (assuming Cl = 35.45), both slow freezing (target temperature: -20°C) and rapid freezing (target temperature: -80°C) maintained the value from before storage (Figure 53). However, when looking at the content (assuming chlorite (HClO2 = 68.46)), the slow freezing (target temperature: -20°C) group showed a slight downward trend (Figure 54). This indicates that the amount of substance (total chlorine) that can be measured by the KI method is gradually decreasing. As long as the free chlorine concentration (assuming Cl=35.45), which is an indicator of oxidizing power (bactericidal power), is maintained, both slow freezing (reached temperature: -20°C) and rapid freezing (reached temperature: -80°C) can be expected to suppress chlorine gasification through freezing (suppression of water molecule vibration), which is very effective in maintaining the function of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•). Rapid freezing (reached temperature: -80°C) suppresses the decrease in the amount of substance (total chlorine) that can be measured by the KI method, and as a result, is more preferable in maintaining the function of the active molecular species of chlorous acid = chlorine peroxide radical (ClOO•).

[0243] As described above, the present invention has been illustrated using preferred embodiments, but it is understood that the scope of the present invention should be interpreted solely by the claims. This application claims priority to Japanese Patent Application No. 2024-230630 (filed December 26, 2024), the contents of which are incorporated herein by reference in their entirety. It is understood that the contents of any patents, patent applications and other documents cited herein should be incorporated herein by reference as if their contents were specifically described herein.

[0244] This technology provides a way to maintain the chemical quality of chlorine peroxide radicals (ClOO•), the main active ingredient in chlorous acid water, for an extended period, and to better maintain the radical-active species in the solution, thereby preventing any change (deterioration) in chemical quality for a certain period.

Claims

1. A method for producing a frozen chlorine peroxide radical solution, comprising: (1) preparing a solution containing chlorine peroxide radicals; and (2) freezing the solution containing chlorine peroxide radicals.

2. The method according to claim 1, wherein the solution is an aqueous solution.

3. The method according to claim 1, comprising cooling the solution to -20°C or below.

4. The method according to claim 1, comprising cooling the solution to -80°C or below.

5. The method according to claim 1, comprising adjusting the filling rate of the container for storing the solution containing the chlorine peroxide radical to 50% or more.

6. The method according to claim 1, comprising removing oxygen from the voids of a container storing the solution containing the chlorine peroxide radical and replacing it with an inert gas.

7. The method according to claim 1, comprising sealing a container for storing the solution containing the chlorine peroxide radical.

8. The method according to claim 1, wherein preparing the solution containing the chlorine peroxide radicals includes thawing a frozen solution containing the chlorine peroxide radicals.

9. The method according to claim 8, comprising stirring the thawed solution containing the chlorine peroxide radical.

10. The method according to claim 5, comprising transferring the container storing the solution containing the chlorine peroxide radical to another container.

11. The method according to claim 1, wherein the solution containing the chlorine peroxide radical is produced by adding an acid to sodium chlorite.

12. A frozen chlorine peroxide radical solution produced by the method described in any one of claims 1 to 11.

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