Method for producing chlorous acid water preparation in which chlorous acid water, chlorous acid as main effective component thereof, and chlorine peroxide radicals as active molecular species thereof have been more efficiently stabilized in liquid at ordinarily temperature in high and low concentrations

Abstract

Provided is a method for producing a chlorous acid water preparation in which chlorous acid water, chlorous acid as a main effective component thereof, and chlorine peroxide radicals as active molecular species thereof have been more efficiently stabilized in the liquid at ordinary temperature in high and low concentrations. The method is for producing a chlorous acid water preparation having a predetermined content (in terms of chlorous acid (HClO2=68.46)), and comprises: (1) preparing a buffer solution; (2) obtaining the concentration of the buffer solution; (3) preparing chlorous acid water; (4) obtaining a content in the chlorous acid water (in terms of chlorous acid (HClO2=68.46)); (5) obtaining an amount of the buffer solution required for dilution, from the content in the chlorous acid water (in terms of chlorous acid (HClO2=68.46)) and the predetermined content (in terms of chlorous acid (HClO2=68.46)); and (6) diluting the chlorous acid water with said amount of the buffer solution to produce a chlorous acid water preparation having the predetermined content (in terms of chlorous acid (HClO2=68.46)).

Description

A method for producing a chlorous acid water preparation in which chlorous acid, its main active ingredient, and its active molecular species, chlorine peroxide radicals, are efficiently stabilized in liquid at room temperature at high and low concentrations.

[0001] The present disclosure relates to a method for producing a hypochlorous acid water formulation that can maintain hypochlorous acid water, its main active ingredient, hypochlorous acid, and its active molecular species, chlorine peroxide radicals, in liquid form at room temperature for three years or more in a high-concentration or low-concentration range.

[0002] Chlorous acid water is a mixture of chlorous acid (HClO ２ ) as the main active ingredient. Chlorous acid water has attracted attention as an antibacterial agent, bactericide, disinfectant, antiseptic, and even antiviral agent and food additive (bactericide). The present inventors discovered chlorous acid water and its manufacturing method, and filed a patent application after confirming its bactericidal effect against Escherichia coli (Patent Document 1). Long-term storage of chlorous acid water is also being considered (Patent Document 2).

[0003] The present inventors also discovered that the active molecular species of chlorous acid is a chlorine peroxide radical, discovered a method for producing a chlorine peroxide radical, and discovered that the chlorine peroxide radical is involved in the sterilization of microorganisms (Patent Document 3).

[0004] International Publication No. WO 2008 / 026607 International Publication No. WO 2014 / 188312 International Publication No. WO 2022 / 239801

[0005] The present inventors have succeeded in extending the maintenance of the scientific quality of chlorous acid water and its main active ingredient, chlorous acid, and its active molecular species, chlorine peroxide radical, after production (for example, for more than about 3 years from the date of production (at room temperature, unopened, protected from light)) by changing the formulation of the buffer solution in the formulation of a chlorous acid water preparation that uses chlorous acid water, its main active ingredient, chlorous acid, and its active molecular species, chlorine peroxide radical, to the conditions described in this specification.

[0006] For example, the present disclosure provides the following: (Item 1) A method for producing a chlorous acid water formulation with a predetermined content (as chlorous acid (HClO2 = 68.46)), comprising: (1) preparing a buffer solution; (2) determining the concentration of the buffer solution; (3) preparing chlorous acid water; (4) determining the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)); (5) determining the amount of the buffer solution to be used for dilution from the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) and the predetermined content (as chlorous acid (HClO2 = 68.46)); and (6) diluting the chlorous acid water with the amount of the buffer solution to produce a chlorous acid water formulation with the predetermined content (as chlorous acid (HClO2 = 68.46)). (Item 2) The manufacturing method according to Item 1, wherein the buffer solution is a citrate buffer solution, a phosphate buffer solution, or a mixture thereof. (Item 3) The manufacturing method according to Item 2, wherein the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) is 4.0% to 6.0% by weight. (Item 4) The manufacturing method according to Item 3, wherein the concentration of the citrate buffer solution is 0.01% (0.52 mmol / L as citric acid) to 1% (52 mmol / L as citric acid). (Item 5) The manufacturing method according to Item 3, wherein the concentration of the phosphate buffer solution is 0.098% (0.01 mol / L as phosphoric acid) to 9.8% (1 mol / L as phosphoric acid). (Item 6) The manufacturing method according to Item 4, wherein the liquid ratio of the chlorous acid water to the citrate buffer solution is 9:1 to 1:9. (Item 7) The manufacturing method according to Item 6, wherein, when a citrate buffer solution is used, the liquid ratio of the citrate buffer solution to the chlorous acid water may be 1 part by weight or more or 1 part by weight or less, and the liquid ratio of the citrate buffer solution to the chlorous acid water is 999:1 to 1:999. (Item 8) The manufacturing method according to Item 5, wherein the liquid ratio of the chlorous acid water to the phosphate buffer solution is 1:1 to 1:9. (Item 9) The manufacturing method according to Item 8, wherein, when a phosphate buffer solution is used, the liquid ratio of the phosphate buffer solution to the chlorous acid water is 1 part by weight or more, and specifically, the liquid ratio of the chlorous acid water to the phosphate buffer solution is 1:2 to 1:999. (Item 10) The manufacturing method according to Item 1, wherein the predetermined concentration of the chlorous acid water is 1000 ppm or more.(Claim 11) The manufacturing method according to item 1, wherein the predetermined concentration of the chlorous acid water is less than 1000 ppm.

[0007] It is contemplated that the present disclosure may provide one or more of the above-described features in combinations other than those explicitly stated. Still further embodiments and advantages of the present disclosure will be recognized by those skilled in the art upon reading and understanding the following detailed description, if necessary.

[0008] After production, the maintenance of the scientific quality of chlorous acid water and its main active ingredient, chlorous acid, and its active molecular species, chlorine peroxide radicals, can be extended.For example, according to the invention of the present disclosure, the scientific quality of chlorous acid water and its main active ingredient, chlorous acid, and its active molecular species, chlorine peroxide radicals, can be maintained for approximately 3 years or more (at room temperature, unopened, protected from light) from the date of production.

[0009] Figure 1-1 shows the change in content over time in samples E6 and E7 of Example 1. Figure 1-2 shows the change in free chlorine concentration over time in samples E6 and E7 of Example 1. Figure 2-1 shows the change in content over time in samples A2, B2, E6, and E7 of Example 1. Figure 2-2 shows the change in free chlorine concentration over time in samples A2, B2, E6, and E7 of Example 1. Figure 3-1 shows the change in free chlorine concentration over time in the chlorous acid water formulation of Example 2. Figure 3-2 shows the change in content over time in the chlorous acid water formulation of Example 2. Figure 3-3 shows the change in pH over time in the chlorous acid water formulation of Example 2. Figure 4-1 shows the change in free chlorine concentration over time in the chlorous acid water formulation of Example 2. Figure 4-2 shows the change in content over time in the chlorous acid water formulation of Example 2. Figure 4-3 shows the change in pH over time in the chlorous acid water formulation of Example 2. FIG. 5 shows the change over time in the content of the hypochlorous acid water formulation of Example 2. FIG. 6 shows the change over time in the residual rate of the hypochlorous acid water formulation of Example 2. FIG. 7 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 2. FIG. 8-1 shows the change over time in the content of the hypochlorous acid water formulation of Example 3. FIG. 8-2 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 3. FIG. 9-1 shows the change over time in the content of the hypochlorous acid water formulation of Example 4. FIG. 9-2 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 4. FIG. 10 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 5. FIG. 11 shows the change over time in the content of the hypochlorous acid water formulation of Example 5. FIG. 12 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 6. Figure 13-1 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 6. Figure 13-2 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 6. Figure 13-3 shows the change over time in the free chlorine concentration of the hypochlorous acid water formulation of Example 6. Figure 14-1 shows the change over time in the content of the hypochlorous acid water formulation of Example 6. Figure 14-2 shows the change over time in the content of the hypochlorous acid water formulation of Example 6. Figure 14-3 shows the change over time in the content of the hypochlorous acid water formulation of Example 6. Figure 15 shows the cyclic reaction of chlorine peroxide radicals.

[0010] The present disclosure will be described in more detail below. Throughout this specification, unless otherwise specified, singular expressions should be understood to include the plural concept. Therefore, singular articles (e.g., "a," "an," "the," etc. in English) should be understood to include the plural concept unless otherwise specified. Furthermore, it should be understood that terms used in this specification are used in the sense commonly used in the relevant field unless otherwise specified. Therefore, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In the case of conflict, the present specification (including definitions) will prevail.

[0011] Abbreviations used herein have their conventional meaning within the art unless otherwise specified.

[0012] References herein to "about" a value or parameter include the variation that is directed to the value or parameter itself. For example, "about X" includes "X" itself as well as values ​​that allow for ±10% of error, unless otherwise specified.

[0013] In this specification, "chlorous acid water" refers to chlorous acid (HClO ２ ) for a long period of time. ２ When a sample of chlorous acid water is measured using a spectrophotometer, if two absorption peaks are simultaneously observed in the UV spectrum between 240 and 420 nm, one at around 260 nm and the other at around 350 nm, i.e., if a double nodule is observed, the presence of chlorous acid water can be confirmed.

[0014] Chlorous acid water can be produced by the methods disclosed in International Publication Nos. WO2008 / 026607, WO2014 / 188310, WO2014 / 188311, WO2014 / 188312, WO2015 / 093062, and WO2017 / 170904.

[0015] "Hypochlorous acid water" was designated as a food additive on February 1, 2013, and is a disinfectant whose main active ingredient is hypochlorous acid (HClO2). Hypochlorous acid (HClO2), the main active ingredient in "hypochlorous acid water," is a metastable chemical substance that is recognized by the US USDA and FDA as a particularly safe substance and is classified as a food additive: processing aid.

[0016] Moreover, hypochlorous acid water is capable of exerting a strong bactericidal effect even in the presence of organic matter, and was highly praised by the National Institute of Health Sciences (commonly known as the National Institute of Health Sciences) in its "2015 Survey on Inactivation Conditions for Norovirus," which stated that "hypochlorous acid water was the only product that was able to inactivate norovirus to below the detection limit under all loading conditions." As the Food Sanitation Act Enforcement Regulations have been revised, hypochlorous acid water has been increasingly included in the "Mass Cooking Facility Cooking Manual," etc., following the occurrence of large-scale food poisoning incidents.

[0017] In addition, it has been approved for manufacture and sale as a Class 2 disinfectant and sterilizing drug, and is listed in various hygiene standards, including the "Q&A about Norovirus" and other guidelines such as the "Guidelines for Infectious Disease Control in Daycare Centers" administered by the Ministry of Health, Labor and Welfare, as well as related manuals such as the "Manual for Infection Control in Elderly Care Support Facilities." It is a substance that is supplied to a wide range of markets in Japan's food hygiene and environmental hygiene markets.

[0018] "Chlorous acid water," whose main active ingredient is hypochlorous acid, has a bactericidal effect equal to or even stronger than "hypochlorous acid water" or "sodium hypochlorite," but its reactivity is slow, and although it does not have an instantaneous bactericidal effect (fast acting), it has a gentle reactivity while still maintaining accurate bactericidal power, and what's more, it has the characteristic of maintaining stable bactericidal power. Therefore, even in dirty environments with a lot of organic matter, where chlorine oxide-based chemicals have been said to be the weakest, hypochlorous acid water can slowly but surely and accurately exert a bactericidal effect (bactericidal power against microorganisms lurking in dirt).

[0019] As a result, it is effective in inactivating resistant bacteria that have been difficult to sterilize until now (heat-resistant bacteria that increase their resistance by forming spores, and drug-resistant bacteria that are no longer affected by antibiotics), fungi such as mold and yeast, and even viruses (including both enveloped and non-enveloped viruses). "Chlorous acid water" does not need to be adjusted before use, and no special generator is required, so anyone can use it wherever they want, whenever they want, and it is safe.

[0020] Furthermore, the effectiveness of hypochlorous acid water in the presence of organic matter is also published on the Ministry of Health, Labour and Welfare's website in the "2015 Research Report on Inactivation Conditions for Norovirus (National Institute of Health Food Sanitation Control Division)."

[0021] It has been discovered that the active molecular species of chlorous acid, which is the main active ingredient of chlorous acid water, is a chlorine peroxide radical (Patent Document 3).

[0022] As used herein, "chlorine peroxide radical" refers to a peroxide radical having two oxygen atoms per chlorine atom, where the radical is on the oxygen atom rather than the chlorine atom. Therefore, it differs from the chlorine dioxide radical (O=Cl·=O), which has a radical on the chlorine atom. The fact that the chlorine peroxide radical differs from the chlorine dioxide radical can be confirmed by ESR measurement. The chlorine peroxide radical has a peroxide radical structure, considered to be a Cl-O-O· structure, which is clearly different from the structure of the chlorine dioxide radical (O=Cl·=O). The chlorine peroxide radical has a maximum absorbance wavelength of 350-360 nm. As a radical, it has low reactivity and can exist stably for a long period of time.

[0023] In this specification, "free chlorine," "free chlorine concentration," or "free residual chlorine concentration" refers to a value measured by Appendix 3 of the "Testing Method for Free Residual Chlorine and Combined Chlorine Established by the Minister of Health, Labour and Welfare Pursuant to the Provisions of Article 17, Paragraph 2 of the Enforcement Regulations of the Water Supply Act" (hereinafter referred to as the colorimetric method (DPD indicator)), and is a value obtained by oxidizing the DPD indicator.

[0024] As used herein, the term "buffer" refers to a solution with buffering properties, such as a mixture of a weak acid and its conjugate base, or a weak base and its conjugate acid. Examples of such a solution include acetate buffer, phosphate buffer, citrate buffer, citrate-phosphate buffer, borate buffer, tartrate buffer, and Tris buffer. The solution may contain sodium salts, potassium salts, etc.

[0025] In this specification, "high concentration" or "high concentration range" means that the concentration of chlorous acid water is high, and may be 1000 ppm or more, 1500 ppm or more, 2000 ppm or more, 2500 ppm or more, 3000 ppm or more, 4000 ppm or more, 5000 ppm or more, 6000 ppm or more, 7000 ppm or more, or 8000 ppm or more.In this specification, "low concentration" or "low concentration range" means that the concentration of chlorous acid water is low, and may be less than 1000 ppm, 950 ppm or less, 900 ppm or less, 800 ppm or less, 700 ppm or less, 600 ppm or less, 500 ppm or less, 400 ppm or less, 300 ppm or less, or 200 ppm or less.In addition, 1 wt% = 10,000 ppm.

[0026] (Preferred Embodiments) Preferred embodiments of the present disclosure will be described below. The embodiments provided below are provided for a better understanding of the present disclosure, and it is understood that the scope of the present disclosure should not be limited to the following description. Therefore, it is clear that those skilled in the art can make appropriate modifications within the scope of the present disclosure in light of the description herein. It is also understood that the following embodiments of the present disclosure can be used alone or in combination.

[0027] In one aspect of the present disclosure, a method for producing a chlorous acid water formulation of a predetermined concentration, i.e., content (as chlorous acid (HClO2 = 68.46)) is provided. The method for producing a chlorous acid water formulation of a predetermined concentration of the present disclosure includes: (1) preparing a buffer solution; (2) determining the concentration of the buffer solution; (3) preparing chlorous acid water; (4) determining the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)); (5) determining the amount of the buffer solution for dilution from the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) and the predetermined content (as chlorous acid (HClO2 = 68.46)); and (6) diluting the chlorous acid water with the amount of the buffer solution to produce a chlorous acid water formulation of the predetermined content (as chlorous acid (HClO2 = 68.46)).

[0028] Buffers that can be used include phosphate buffers and citrate buffers. Phosphate buffers can include disodium hydrogen phosphate, sodium dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, and potassium dihydrogen phosphate. Citrate buffers can include trisodium citrate, tripotassium citrate, and the like.

[0029] In one embodiment of the present disclosure, the buffer is a citrate buffer, a phosphate buffer, or a mixture thereof.

[0030] In one embodiment of the present disclosure, the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) is 4.0 wt% to 6.0 wt% (40,000 ppm to 60,000 ppm). The lower limit of the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) is 4.0 wt%, 4.1 wt%, 4.2 wt%, 4.3 wt%, 4.4 wt%, 4.5 wt%, 4.6 wt%, 4.7 wt%, 4.8 wt%, 4.9 wt%, 5.0 wt%, 5.1 wt%, 5.2 wt%, 5.3 wt%, 5.4 wt%, 5.5 wt%, 5.6 wt%, 5.7 wt%, In one embodiment of the present disclosure, the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be in a range between any of the above lower and upper limits.

[0031] In one embodiment of the present disclosure, the concentration of the citrate buffer is 0.01% (0.52 mmol / L as citric acid) to 1% (52 mmol / L as citric acid). The lower limit of the concentration of the citrate buffer may be 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, or 0.9%, and the upper limit may be 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, 0.1%, 0.09%, 0.08%, 0.07%, 0.06%, 0.05%, 0.04%, 0.03%, or 0.02%.Alternatively, the lower limit of the concentration of the citrate buffer solution is 0.052 mol / L, 0.053 mol / L, 0.054 mol / L, 0.055 mol / L, 0.056 mol / L, 0.057 mol / L, 0.058 mol / L, 0.059 mol / L, 0.06 mol / L, 0.07 mol / L, 0.08 mol / L, 0.09 mol / L, 0.1 mol / L, 0.2 mol / L, 0.3 ... .. 4mol / L, 0.5mol / L, 0.6mol / L, 0.7mol / L, 0.8mol / L, 0.9mol / L, 1mol / L, 2mol / L, 3mol / L, 4mol / L, 5mol / L, 6m ol / L, 7mol / L, 8mol / L, 9mol / L, 10mol / L, 15mol / L, 20mol / L, 25mol / L, 30mol / L, 35mol / L, 40mol / L, 45mol / L , 50 mol / L, and the upper limit is 52 mol / L, 51 mol / L, 50 mol / L, 49 mol / L, 48 mol / L, 47 mol / L, 46 mol / L, 45 mol / L, 44 mol / L, 43mol / L, 42mol / L, 41mol / L, 40mol / L, 35mol / L, 30mol / L, 25mol / L, 20mol / L, 15mol / L, 10mol / L, 9mol / L, 8mol In one embodiment of the present disclosure, the concentration of the citrate buffer may be in a range between any of the lower and upper limits mentioned above.

[0032] In one embodiment of the present disclosure, the concentration of the phosphate buffer is 0.098% (0.01 mol / L as phosphate) to 9.8% (1 mol / L as phosphate). The lower limit of the concentration of the phosphate buffer may be 0.098%, 0.099%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, or 9%, and the upper limit may be 9.8%, 9.7%, 9.6%, 9.5%, 9.4%, 9.3%, 9.2%, 9.1%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, or 1%. Alternatively, the lower limit of the concentration of the phosphate buffer solution is 0.01 mol / L, 0.02 mol / L, 0.03 mol / L, 0.04 mol / L, 0.05 mol / L, 0.06 mol / L, 0.07 mol / L, 0.08 mol / L, 0.09 mol / L, 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, or 0.9 mol / L. and the upper limit may be 1 mol / L, 0.9 mol / L, 0.8 mol / L, 0.7 mol / L, 0.6 mol / L, 0.5 mol / L, 0.4 mol / L, 0.3 mol / L, 0.2 mol / L, 0.1 mol / L, 0.09 mol / L, 0.08 mol / L, 0.07 mol / L, 0.06 mol / L, 0.05 mol / L, 0.04 mol / L, 0.03 mol / L, or 0.02 mol / L. In one embodiment of the present disclosure, the concentration of the phosphate buffer may be in a range between any of the above lower and upper limits.

[0033] In one embodiment of the present disclosure, the liquid ratio of the chlorous acid water to the citrate buffer solution is 1:1, 9:1, or 1:9.

[0034] In one embodiment of the present disclosure, when a citrate buffer solution is used, the liquid ratio of the citrate buffer solution to chlorous acid water may be 1 part more or less than 1 part, and the liquid ratio of the citrate buffer solution to chlorous acid water may be 999:1 to 1:999, for example, 1:2, 2:1, 1:9, or 9:1. Dilution is possible in both patterns of 9:1, 99:1, 999:1, ... or 1:9, 1:99, 1:999 ....

[0035] In one embodiment of the present disclosure, the liquid ratio of the chlorous acid water to the phosphate buffer solution is 1:1 to 1:9, and may be, for example, 1:1 or 1:9.

[0036] In one embodiment of the present disclosure, the predetermined concentration of the chlorous acid water is 1000 ppm or more, and may be, for example, 1500 ppm or more, 2000 ppm or more, 2500 ppm or more, 3000 ppm or more, 4000 ppm or more, 5000 ppm or more, 6000 ppm or more, 7000 ppm or more, or 8000 ppm or more.

[0037] In one embodiment of the present disclosure, the predetermined concentration of the chlorous acid water is less than 1000 ppm, and may be, for example, 950 ppm or less, 900 ppm or less, 800 ppm or less, 700 ppm or less, 600 ppm or less, 500 ppm or less, 400 ppm or less, 300 ppm or less, or 200 ppm or less.

[0038] In one embodiment of the present disclosure, when a phosphate buffer solution is used, the liquid ratio must be at least 1 part chlorous acid water to 1 part phosphate buffer solution. Specifically, the liquid ratio of chlorous acid water to phosphate buffer solution is 1:1 to 1:999, and the dilution is limited to patterns such as 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:99, or 1:999...

[0039] In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.1 wt% or more, 0.15 wt% or more, 0.2 wt% or more, 0.25 wt% or more, 0.3 wt% or more, 0.4 wt% or more, 0.5 wt% or more, 0.6 wt% or more, 0.7 wt% or more, 0.8 wt% or more, 0.9 wt% or more, 1.0 wt% or more, 1.1 wt% or more, or 1.2 wt% or more. In certain embodiments, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.4 wt% or more, 0.5 wt% or more, 0.6 wt% or more, 0.7 wt% or more, 0.8 wt% or more, 0.9 wt% or more, 1.0 wt% or more, 1.1 wt% or more, or 1.2 wt% or more. For such concentrations, a citrate buffer solution may be used.

[0040] In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.2 wt% or less, 0.19 wt% or less, 0.18 wt% or less, 0.17 wt% or less, 0.16 wt% or less, 0.15 wt% or less, 0.14 wt% or less, 0.13 wt% or less, 0.12 wt% or less, 0.11 wt% or less, 0.10 wt% or less, 0.09 wt% or less, 0.08 wt% or less, 0.07 wt% or less, 0.06 wt% or less, 0.05 wt% or less, 0.04 wt% or less, 0.03 wt% or less, or 0.02 wt% or less. In certain embodiments, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.05 wt% or less, 0.04 wt% or less, 0.03 wt% or less, or 0.02 wt% or less. For such concentrations, a phosphate buffer solution may be used.

[0041] In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.02 wt % to 1.2 wt %. In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.02 wt % to 0.05 wt %. In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.1 wt % to 0.2 wt %. In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.4 wt % to 1.2 wt %.

[0042] In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.4 wt % to 0.8 wt %. In one embodiment of the present disclosure, the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) may be 0.8 wt % to 1.2 wt %. For example, when the predetermined content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) is 0.1 wt % to 0.2 wt %, a citrate buffer or a phosphate buffer may be used.

[0043] (Chlorous Acid Water and Its Production Examples) The chlorous acid water used in the present disclosure has characteristics discovered by the present inventors. Chlorous acid water produced by any method, such as the known production methods described in the above-mentioned literature, can be used. A typical composition, for example, can be a mixture of 61.40% chlorous acid water, 1.00% potassium dihydrogen phosphate, 0.10% potassium hydroxide, and 37.50% purified water (sold by the applicant. 72% chlorous acid water corresponds to 30,000 ppm of chlorous acid). This agent reduces the attenuation of chlorous acid due to contact with organic matter under acidic conditions while maintaining its bactericidal effect. In addition, it generates only a small amount of chlorine gas and has the characteristic of suppressing the amplification of the odor caused by the mixture of chlorine and organic matter.

[0044] In one embodiment, the chlorous acid water of the present disclosure can be produced by adding sulfuric acid or an aqueous solution thereof to an aqueous sodium chlorate solution in an amount and concentration capable of maintaining the pH value of the aqueous solution at 3.4 or less, to generate chloric acid, and then adding hydrogen peroxide in an amount equal to or greater than the amount required for the reduction reaction of the chloric acid.

[0045] In another embodiment, the chlorous acid water of the present disclosure can be produced by adding sulfuric acid or an aqueous solution thereof to an aqueous sodium chlorate solution in an amount and concentration capable of maintaining the pH value of the aqueous solution at 3.4 or less, to generate chloric acid by reaction, and then adding hydrogen peroxide in an amount equal to or greater than the amount required for the reduction reaction of the chloric acid to generate chlorous acid.Then, any one of an inorganic acid or an inorganic acid salt alone, or two or more of them alone or a combination of these, is added to the aqueous solution to adjust the pH value to within the range of 3.2 to 8.5.

[0046] Furthermore, in another embodiment, the chlorous acid water of the present disclosure can be produced by adding sulfuric acid or an aqueous solution thereof to an aqueous sodium chlorate solution in an amount and concentration capable of maintaining the pH value of the aqueous solution at 3.4 or less, to generate chloric acid by reaction, and then adding hydrogen peroxide in an amount equal to or greater than the amount required for the reduction reaction of the chloric acid to generate chlorous acid.Then, any one or two or more of an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt, or a combination of these can be added to the aqueous solution to adjust the pH value to within the range of 2.9 to 8.5.

[0047] Furthermore, in another embodiment, the chlorous acid water of the present disclosure can be produced by adding sulfuric acid or an aqueous solution thereof to an aqueous sodium chlorate solution in an amount and concentration capable of maintaining the pH value of the aqueous solution at 3.4 or less, to generate chloric acid by reacting the solution, and then adding hydrogen peroxide in an amount equal to or greater than the amount required for the reduction reaction of the chloric acid to generate chlorous acid in the aqueous solution, and then adding any one or more of an inorganic acid or an inorganic acid salt, or any one or more of an inorganic acid or an inorganic acid salt, or any one or more of an organic acid or an organic acid salt, or any one or more of an inorganic acid or an inorganic acid salt, or any one or more of an organic acid or an organic acid salt, to adjust the pH value to within the range of 3.2 to 8.5.

[0048] In another embodiment, the inorganic acid used in the above method may be carbonic acid, phosphoric acid, boric acid, or sulfuric acid.

[0049] Furthermore, in another embodiment, the inorganic acid salt may be a carbonate, an inorganic hydroxide, a phosphate, or a borate.

[0050] In another embodiment, the carbonate may be sodium carbonate, potassium carbonate, sodium bicarbonate, or potassium bicarbonate.

[0051] Furthermore, in another embodiment, the inorganic hydroxide may be sodium hydroxide, potassium hydroxide, calcium hydroxide, or barium hydroxide.

[0052] Furthermore, in another embodiment, the phosphate may be disodium hydrogen phosphate, sodium dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, or potassium dihydrogen phosphate.

[0053] In another embodiment, the borate may be sodium borate or potassium borate.

[0054] Furthermore, in another embodiment, the organic acid may be succinic acid, citric acid, malic acid, acetic acid, or lactic acid.

[0055] Furthermore, in another embodiment, the organic acid salt may be sodium succinate, potassium succinate, sodium citrate, potassium citrate, sodium malate, potassium malate, sodium acetate, potassium acetate, sodium lactate, potassium lactate, or calcium lactate.

[0056] Chlorous acid (HClO) can be used as a bacterial killer. ２ In the method for producing an aqueous solution (chlorous acid water) containing sodium chlorate (NaClO ３ ) in an aqueous solution of sulfuric acid (H ２ SO ４ ) or its aqueous solution to create acidic conditions, ３ ) to convert it into chlorous acid by reduction reaction, ２ O ２ ) to obtain chlorous acid (HClO ２ The basic chemical reactions in this manufacturing method are shown in the following formulas A and B.

[0057]

[0058] In formula A, sodium chlorate (NaClO ３ ) sulfuric acid (H ２ SO ４ ) or its aqueous solution to obtain chloric acid. ３ ) is hydrogen peroxide (H ２ O２ ) and reduced by chlorous acid (HClO ２ ) is generated.

[0059]

[0060] At that time, chlorine dioxide gas (ClO ２ ) is generated (C), but hydrogen peroxide (H ２ O ２ ) through reactions D to F, ２ ) to generate the

[0061] By the way, the generated chlorous acid (HClO ２ ) occurs when multiple chlorous acid molecules decompose with each other or form chloride ions (Cl － It has the property of decomposing quickly into chlorine dioxide gas and chlorine gas in the presence of chlorous acid (HClO), hypochlorous acid (HClO), and other reducing substances. Therefore, in order to be useful as a bactericide, ２ ) must be prepared so that the state can be maintained for a long time.

[0062] Therefore, the chlorous acid (HClO ２ ) or chlorine dioxide gas (ClO ２ By adding an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt alone, or two or more kinds alone or a combination of these to an aqueous solution containing these, a transition state is created, and the decomposition reaction is delayed, thereby allowing chlorous acid (HClO ２ ) can be maintained stably.

[0063] In one embodiment, the chlorous acid (HClO ２ ) or chlorine dioxide gas (ClO ２ ) or an aqueous solution containing these to which an inorganic acid or an inorganic acid salt, specifically a carbonate or an inorganic hydroxide, is added alone or in combination with two or more kinds of them, can be used.

[0064] In another embodiment, an aqueous solution containing an inorganic acid or an inorganic acid salt, specifically a carbonate or an inorganic hydroxide, either alone or in combination, to which an inorganic acid, an inorganic acid salt, an organic acid or an organic acid salt, either alone or in combination, can be added.

[0065] In addition, in yet another embodiment, an aqueous solution prepared by the above method can be used in which an inorganic acid, an inorganic acid salt, an organic acid or an organic acid salt is added alone or in combination with two or more kinds of inorganic acid, an inorganic acid salt, an organic acid or an organic acid salt.

[0066] Examples of the inorganic acid include carbonic acid, phosphoric acid, boric acid, and sulfuric acid. Examples of inorganic acid salts include carbonates, inorganic hydroxides, and phosphates and borates. More specifically, examples of carbonates include sodium carbonate, potassium carbonate, sodium bicarbonate, and potassium bicarbonate. Examples of inorganic hydroxides include sodium hydroxide, potassium hydroxide, calcium hydroxide, and barium hydroxide. Examples of phosphates include disodium hydrogen phosphate, sodium dihydrogen phosphate, trisodium phosphate, tripotassium phosphate, dipotassium hydrogen phosphate, and potassium dihydrogen phosphate. Examples of borates include sodium borate and potassium borate. Examples of the organic acid include succinic acid, citric acid, malic acid, acetic acid, and lactic acid. Examples of organic acid salts that are suitable include sodium succinate, potassium succinate, sodium citrate, potassium citrate, sodium malate, potassium malate, sodium acetate, potassium acetate, sodium lactate, potassium lactate, and calcium lactate.

[0067] When an acid and / or its salt is added, Na ＋ +ClO ２ － ⇔ Na － ClO ２ Ya K ＋ +ClO ２ － ⇔ K-ClO ２ and H ＋ +ClO ２ － ⇔ H-ClO ２This creates a transition state, resulting in chlorous acid (HClO ２ ) of chlorine dioxide (ClO ２ This can slow down the progression to chlorous acid (HClO ２ ) for a long time, and chlorine dioxide (ClO ２ ) is generated with little chlorous acid (HClO ２ ) can be produced.

[0068] The decomposition of chlorite in acidic solution is shown below.

[0069]

[0070] As expressed by this formula, the decomposition rate of the chlorite aqueous solution at pH becomes higher as the pH becomes lower, i.e., the acidity becomes stronger. That is, the absolute rates of reactions (a), (b), and (c) in the above formula increase. For example, the proportion of reaction (a) becomes smaller as the pH becomes lower, but the total decomposition rate fluctuates greatly, i.e., becomes larger, so that chlorine dioxide (ClO ２ The amount of chlorine dioxide gas (ClO) generated also increases with decreasing pH. Therefore, the lower the pH value, the faster the sterilization and bleaching will occur, but the amount of irritating and harmful chlorine dioxide gas (ClO) generated will also increase. ２ ) makes work difficult and has adverse effects on human health. In addition, the reaction of chlorous acid with chlorine dioxide proceeds quickly, making chlorous acid unstable and shortening the time it can maintain its bactericidal power.

[0071] Therefore, chlorous acid (HClO ２ When the inorganic acid, inorganic acid salt, organic acid, or organic acid salt is added to the aqueous solution containing the inorganic acid, inorganic acid salt, organic acid, or organic acid salt, the pH value is adjusted to within the range of 2.9 to 8.5 from the viewpoint of the balance between the inhibition of chlorine dioxide generation and the bactericidal activity.

[0072] The chlorous acid water of the present disclosure can also be an aqueous solution obtained by adding hydrochloric acid to a saturated sodium chloride solution, electrolyzing the solution in a membraneless electrolytic cell (which is composed of an anode and a cathode that are not separated by a membrane) under acidic conditions, adding sulfuric acid to the aqueous solution to make it strongly acidic, and then adding hydrogen peroxide water to the chlorous acid thus produced to react with it.The chlorous acid water can be the one described in the 10th edition of the Official Specification of Food Additives 2024 (Ministry of Health, Labor and Welfare, Consumer Affairs Agency).

[0073] The chlorous acid water of the present disclosure also contains chlorine dioxide gas (ClO ２ By trapping (trapping or adsorbing) chlorous acid (HClO) in an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt, either alone or in combination of two or more kinds, a transition state is created, and the decomposition reaction is delayed, thereby allowing chlorous acid (HClO) to be decomposed for a long period of time. ２ ) can be stably maintained in water. These methods can be utilized by further adding to the aqueous solution an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt, either alone or in combination. The TAL of aqueous solution A containing either an inorganic acid, an inorganic acid salt, an organic acid, or an organic acid salt, either alone or in combination, is 20 to 2000, where the TAL is determined by the titration amount of 0.1 N HCl from an initial pH of 11.0 or less to a pH of 4.

[0074] Examples of hypochlorous acid water preparations that can be used in the present disclosure include "Care for Hands," "Care for Hands Pro-Free," "Care for Fresh," "Outlock Super," "New Outlock SP," "Care Forpis Pro-Free," "Care for No. 3," "Care for Norobaria Plus," "Care for No. 15," "Chlorus Care 8," "Chlorus Care 10," "Microlassan," "Chlorus Acid N Barrier," "Microlassan R," and "Microlassan UP," all manufactured by Sankei Co., Ltd.

[0075] The chlorine peroxide radical (Clo·) used in the present disclosure can be produced by contacting an excess amount of hydrogen ions with a solution containing chlorine oxide having a moiety containing two or more oxygen atoms per chlorine atom. The excess amount can be determined by an increase in the maximum absorption at 354 nm in the UV spectrum. The concentration at which an increase in absorbance at 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 relative to chlorine oxide. We have found that adding an excess amount of hydrogen ions generates chlorine peroxide radicals, which are peroxide radicals, from chlorine oxide. Due to the excess 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, or 10 or less. The reaction can be carried out at room temperature in the atmosphere. In the case of chlorine oxides containing more than two oxygen atoms (e.g., 2.5, 3, 3.5, or 4) per chlorine atom, such as chloric acid or perchloric acid, as a raw material, chlorine peroxide radicals can be generated by adding an excess amount of hydrogen ions to the chlorine oxides. Without wishing to be bound by theory, the presence of the generated chlorine peroxide radicals can be confirmed by ESR.

[0076] 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 ions, chloric acid, chlorate, chlorate ions, perchloric acid, perchlorate, and / or perchlorate ions.

[0077] In one embodiment of the present disclosure, the chlorine oxide is in the form of an aqueous solution, which may be a desirable embodiment because the aqueous solution is easy to handle and relatively easily promotes the generation of chlorine peroxide radicals.

[0078] In one embodiment of the present disclosure, the step of contacting hydrogen ions includes adding an acid. In one embodiment of the present disclosure, the acid is a GRAS acid. GRAS acids are substances generally regarded as safe and can help to safely produce and use chlorine peroxide radicals.

[0079] In one embodiment of the present disclosure, the step of contacting hydrogen ions comprises contacting H ＋ This involves using a type H ion exchange resin. ＋ The type ion exchange resin may be any type that provides hydrogen ions. ＋ The ion exchange resin may be added directly to the chlorine oxide as a powder, or the chlorine oxide may be passed through a column containing the ion exchange resin.

[0080] 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.

[0081] In one aspect of the present disclosure, a composition containing chlorine peroxide radicals is provided, and preferably, an aqueous solution containing chlorine peroxide radicals is provided. In the aqueous solution containing chlorine peroxide radicals of the present disclosure, the chlorine peroxide radicals can exist stably for a long period of time, for example, for 24 hours, 7 days, or even for one month or more.

[0082] In one embodiment of the present disclosure, the chlorine peroxide radical is present as an active ingredient of a disinfectant. As described above, the chlorine peroxide radical can exist stably in an aqueous solution for a long period of time, for example, for 24 hours, 7 days, or even for one month or more. Therefore, in the present disclosure, the composition of the present disclosure can be provided as a long-lasting disinfectant.

[0083] (Problems in comparing and evaluating the antimicrobial effects of chlorous acid water and sodium hypochlorite) One problem with comparing and evaluating the antimicrobial effects of chlorous acid water and sodium hypochlorite is that chlorine oxide concentrations are expressed as both effective chlorine concentration and free chlorine, and antimicrobial effectiveness depends on free chlorine, which is the source of oxidizing power. While the relationship between free chlorine and effective chlorine concentration for sodium hypochlorite is nearly 1:1, the effective chlorine concentration and free chlorine for chlorous acid water do not coincide, as with sodium hypochlorite. Therefore, when comparing the bactericidal power of the two chemicals on the same level, it is necessary to compare the oxidizing power, which indicates antimicrobial effectiveness, in other words, free chlorine, rather than the effective chlorine concentration.

[0084] The oxidizing power of chlorine oxide agents is generally determined by measurement methods that utilize colorimetric methods such as the DPD method or the TMB method. However, unlike sodium hypochlorite, there are no standards for measuring free chlorine in chlorous acid water. Therefore, a calibration curve is created by setting the oxidizing power of 1 mg / L of free chlorine (as Cl) in sodium hypochlorite as 1. Note that oxidizing power can be expressed in free chlorine (as Cl), and when comparing with the same free chlorine, the free chlorine (as Cl) in sodium hypochlorite is generated from Cl radicals, while the free chlorine in chlorous acid water is generated from HClO. ２ Since it is a source of sodium hypochlorite, if it is evaluated using standards based on these, it will be difficult to compare, so as with sodium hypochlorite, it will be calculated as oxidizing power 1 = free chlorine (as Cl) 1 mg / L, and by using the same standards, it will be compared and evaluated on the same basis as sodium hypochlorite.

[0085] The method for measuring free chlorine (as Cl) is to add a buffer solution and a DPD indicator to the sample and measure the wavelength at 510 nm with an absorptiometer, while the measurement of free chlorine (as Cl) in the presence of organic matter is performed using a TMB reagent at a wavelength of 655 nm, and the concentration is calculated from the measured value. Furthermore, the method for confirming the bactericidal effect is to prepare the free chlorine (as Cl) of the test agent using the DPD method, contact each agent with an organic matter-containing bacterial solution, and after a certain period of time, neutralize it with sodium thiosulfate, and check the number of surviving bacteria in this neutralized solution.

[0086]

[0087] It should be understood that all references cited herein, including scientific literature, patents, patent applications, and the like, are incorporated by reference in their entirety to the same extent as if each were specifically set forth.

[0088] The present disclosure has been described above by showing preferred embodiments for ease of understanding. Hereinafter, the present disclosure will be described based on examples. However, the above description and the following examples are provided for illustrative purposes only, and are not intended to limit the present invention. Therefore, the scope of the present invention is not limited to the embodiments or examples specifically described herein, but is limited only by the claims.

[0089] (Quantitative method for quantification of chlorous acid solution) Accurately weigh out approximately 5 g of this product and add water to make exactly 500 ml to use as the sample solution. Accurately measure 20 ml of the sample solution and place it in an iodine flask. Add 10 ml of sulfuric acid (1 → 10), then add 1 g of potassium iodide. Immediately seal and shake well. Add 5 ml of potassium iodide TS to the top of the iodine flask and leave in a dark place for 15 minutes. Next, loosen the stopper and pour in the potassium iodide TS. Immediately seal and shake well. Titrate the liberated iodine with 0.1 mol / L sodium thiosulfate (indicator: 5 ml of starch TS). However, the starch reagent should be added when the solution turns pale yellow near the end point; the end point is when the blue color of the solution disappears. A blank test should be performed separately to correct for this. 1 ml of 0.1 mol / L sodium thiosulfate solution = 1.711 mg HClO ２ ).

[0090] (Production Examples) The chlorous acid water preparations used in the following examples were produced as follows: In this specification, chlorous acid water may be abbreviated as "sub-water", but these terms have the same meaning.

[0091] Hypochlorous acid water component analysis table

[0092]

[0093] Using this chlorous acid water, a chlorous acid water preparation was produced based on the following formulation.

[0094]

[0095]

[0096] The "chlorous acid water preparation produced with chlorous acid water" prepared according to the above preparation method was used to measure the concentration of the "chlorous acid water" according to the above "quantitative method for chlorous acid water," and the chlorous acid water of each example was prepared using a buffer solution (phosphate buffer containing dipotassium hydrogen phosphate and potassium dihydrogen phosphate) prepared to have the free chlorine concentration described in each example.

[0097] The chlorous acid solution was prepared according to the above preparation method using the buffers described.

[0098] Chlorous acid = chlorine peroxide radical (coo·) was generated as described in WO 2022 / 239801.

[0099] GB chlorine dioxide water is chlorine dioxide that meets the People's Republic of China's national standard for chlorine dioxide disinfectants (GB26366-2010).

[0100] Example 1: Accelerated testing of chlorous acid water formulations. Contents at time of manufacture (as chlorous acid (HClO2 = 68.46)) 0.1% and 0.2% products, citrate buffer solution used (storage at 40°C ± 2°C, 75% RH ± 5%)

[0101] 1. Test Overview Accelerated testing will be conducted on two candidate formulations of disinfectants for hands and objects (samples E and F below). These candidate formulations using citrate buffer are intended to guarantee the initial free chlorine concentration (assuming Cl = 35.45) even after three years at room temperature.

[0102]

[0103] 2. Implementation conditions

[0104]

[0105] <Summary of manufacturing process control for specimens> Quality of chlorous acid water Content (as chlorous acid (HClO2 = 68.46)) 4.5% ± 0.2% Free chlorine concentration (as Cl = 35.45) 1,000 mg / L or more

[0106]

[0107]

[0108] <Measurement method> 1) Properties: According to the Japanese Pharmacopoeia General Provisions.

[0109] 2) pH Comply with the Japanese Pharmacopoeia General Test Method (2.54 pH measurement method).

[0110] 3) Content (as chlorous acid (HClO2 = 68.46)): Accurately weigh out approximately 2 g of this product and dilute with water to approximately 50 g (20-fold dilution). Place 20 g of this sample solution in a 300 mL Erlenmeyer flask with a ground stopper and add water to make approximately 150 mL. Add approximately 1 g of potassium iodide and approximately 10 mL of sulfuric acid (1 → 10), stopper, and let stand in a dark place for at least 15 minutes. Then add 0.1 mol / L sodium thiosulfate solution until the solution turns pale yellow. Next, add approximately 1 mL of starch TS and add 0.1 mol / L sodium thiosulfate solution until the solution becomes colorless, and titrate with 0.1 mol / L sodium thiosulfate solution.

[0111] (Formula) Content (as chlorous acid (HClO2 = 68.46)) (%) = (1.711 x 10 -3 × V × f / w) × 100 × k V: Titration volume of 0.1 mol / L sodium thiosulfate solution (mL) f: Factor of 0.1 mol / L sodium thiosulfate solution w: Weight of sample solution (g) k: Dilution factor 1.711 × 10 -3 : Weight (g) of chlorous acid equivalent to 1 mL of 0.1 mol / L sodium thiosulfate solution

[0112] 4) Free chlorine concentration (assuming Cl = 35.45): Add 1 mL of this product to 10 mL with water and mix. Then, add 2 mL of this solution to make 9.5 mL and use the resulting solution as the sample solution. Add 50 mg / L standard chlorine water for determination (Note 1) to water to make 9.5 mL of 1 mg / L, 2 mg / L, 5 mg / L, and 10 mg / L solutions, respectively, to make 9.5 mL. Add 0.5 mL of 0.2 mol / L phosphate buffer (pH 6.5) (Note 2) to the sample and standard solutions, then add approximately 0.1 g of DPD reagent (Note 5) and mix. Then, perform the test using an ultraviolet-visible spectrophotometer. Create a calibration curve from the absorbance (510 nm) of the standard solution, and measure the absorbance of the sample solution from the calibration curve.

[0113] (Note 1) 50 mg / L standard chlorine water for quantitative analysis: Prepare chlorine water by adding sulfuric acid (1 → 5) dropwise to a sodium hypochlorite solution with an available chlorine concentration of approximately 5% and allowing the generated chlorine gas to be absorbed into the water. Place 100 mL of chlorine water in a flask, add 1 g of potassium iodide and sulfuric acid (1 → 5), add 0.1 mol / L sodium thiosulfate solution until the brown color turns pale yellow, then add 5 mL of starch TS, and immediately titrate until the resulting blue color disappears. Calculate the amount of available chlorine (mg / L) contained in the chlorine water from the weight of the 0.1 mol / L sodium thiosulfate solution required for titration. Then, dilute the chlorine water with the measured available chlorine concentration with water to approximately 50 mg / L, and use this as standard chlorine water.

[0114] (Formula) Test conditions: Conforms to the Ministry of Health, Labor and Welfare Notification No. 318 Residual Chlorine Testing Method Available chlorine (mg / L) = 3.545 x g x f1 x 1000 / sample water (mL) f1: 0.1 mol / L sodium thiosulfate solution

[0115] (Note 2) Mix 0.2 mol / L phosphate buffer (pH 6.5) with 100 mL of potassium dihydrogen phosphate solution (0.2 mol / L) (Note 3) and 35.4 mL of sodium hydroxide solution (0.2 mol / L) (Note 4), and then dissolve 0.13 g of 1,2-cyclohexanediaminetetraacetic acid (monohydrate) in the solution.

[0116] (Note 3) Potassium dihydrogen phosphate solution (0.2 mol / L) Dissolve 27.22 g of potassium dihydrogen phosphate in water to make 1 L.

[0117] (Note 4) Sodium hydroxide solution (0.2 mol / L) Dissolve 8.00 g of sodium hydroxide in water to make 1 L.

[0118] (Note 5) DPD reagent: Grind 1.0 g of N,N-diethyl-p-phenylenediamine sulfate in a mortar, add 24 g of anhydrous sodium sulfate, and mix until the crystal grains are not crushed.

[0119] 5) Confirmation test 2) UV spectrum: The aqueous solution of this product (1 → 5 to 10) has maximum absorption at wavelengths of 258 nm to 262 nm and 346 nm to 361 nm.

[0120] (Accelerated Test)

[0121] 1. Purpose To confirm the stability of hypochlorous acid water preparations (content at time of manufacture: 0.1%, 0.2%) in accelerated testing.

[0122] 2. Sample *One is for M+0 measurement.

[0123] 3. Storage conditions, storage period and measurement period 3.1 Storage conditions and packaging 40°C ± 2°C [75% RH ± 5%], PET container (polyethylene terephthalate bottle)

[0124] 3.2 Retention period: 6 months (D+0, M+1, M+2, M+3, M+4, M+5, M+6)

[0125] 3.3 Response to deviations from storage conditions Deviations from storage conditions of less than one hour will not be evaluated. For deviations of longer durations, if the deviation has only a minor effect on quality or if the operating conditions at the time of the deviation are unknown, the deviation time will be accumulated in hours, and if it exceeds one day, the storage period will be extended by one day. However, if the deviation has a severe effect on quality, the storage period will not be extended.

[0126] 4. Test items, etc. 4.1 Test items

[0127] 4.2 Number of test repetitions The test shall be repeated three times.

[0128] 5. Main reagents used

[0129] 6. Main equipment used

[0130] 7. Analysis software used Microsoft Excel will be used for data analysis.

[0131] 8. Summary of Results Sample E6, prepared with a citrate buffer solution at 0.2% chlorous acid (HClO2 = 68.46) at the time of manufacture, and sample F6, prepared with a citrate buffer solution at 0.1% chlorous acid (HClO2 = 68.46) at the time of manufacture, were subjected to accelerated storage tests at 40°C ± 2°C [75% RH ± 5%]. The free chlorine concentrations (based on Cl = 35.45) after six months were 140 mg / L for sample E6 and 83 mg / L for sample F6, meeting the pre-set free chlorine concentration (based on Cl = 35.45) specifications of 50 mg / L or greater and 25 mg / L or greater. Furthermore, the content (based on chlorous acid (HClO2 = 68.46)) after six months was 0.12% for sample E6 and 0.07% for sample F6, representing a 48% and 42% decrease, respectively, compared to the time of manufacture.

[0132]

[0133] The content (as chlorous acid (HClO2 = 68.46)) and free chlorine concentration (as Cl = 35.45) are shown in Figure 1-1 and Figure 1-2, respectively (regression line and lower limit of 95% confidence interval of the regression line): Content (as chlorous acid (HClO2 = 68.46)) Sample E6 Regression line: Y = -0.1071X - 1.4644 (r = -0.994), 95% lower limit: Y = -0.1210X - 1.5147 Sample F6 Regression line: Y = -0.0887X - 2.1855 (r = -0.996), 95% lower limit: Y = -0.0972X - 2.2164 Free chlorine concentration (as Cl = 35.45) Sample E6 Regression line: Y = -0.0064 + 5.0063 (r = -0.373), 95% lower limit: Y = -0.0285 + 4.9202 Sample F6 Regression line: Y = 0.0216 + 4.3264 (r = 0.782), 95% lower limit: Y = -0.0023 + 4.2332

[0134] Next, a regression line was created from the natural logarithm of the measured values ​​of free chlorine concentration (based on Cl = 35.45) and content (based on chlorous acid (HClO2 = 68.46)). The regression line for free chlorine concentration (based on Cl = 35.45) was created using data from the first month onwards, when the measured value of free chlorine concentration (based on Cl = 35.45) was at its maximum. As a result, the absolute value of the correlation coefficient (r) for the free chlorine concentration (assuming Cl = 35.45) was 0.373 for sample E6 and 0.782 for sample F6, indicating a low correlation. When the natural logarithm of the measured values ​​was plotted, it was found that although the measured values ​​increased from the onset to the first month, they then remained almost flat, and the measured value at the sixth month was 140 mg / L for sample E6 (standard value: 50 mg / L or more) and 83 mg / L for sample F6 (standard value: 25 mg / L or more), indicating that the free chlorine concentration (assuming Cl = 35.45) remained high.

[0135] Furthermore, when the period until the content (as chlorous acid (HClO2 = 68.46)) was reduced by half was calculated from the regression line of the content (as chlorous acid (HClO2 = 68.46)), it was 7 months for sample E6 and 9 months for sample F6. When calculated using the lower limit of the 95% confidence interval, it was 6 months for sample E6 and 8 months for sample F6, indicating that the half-life in both cases was 6 months or longer.

[0136] 9. Conclusions The free chlorine concentration (as Cl = 35.45) at 40°C ± 2°C [75% RH ± 5%] for sample E6, which was prepared with a citrate buffer solution to a 0.2% concentration (as chlorous acid (HClO2 = 68.46)) at the time of manufacture, and sample F6, which was prepared with a 0.1% concentration, showed little fluctuation and remained stable from the first month through the sixth month of storage. Furthermore, the measured values ​​for samples E6 and F6 at the sixth month were 140 mg / L and 83 mg / L, respectively, which were above the predetermined specifications of 50 mg / L and 25 mg / L. Therefore, the long-term storage test data will be used to determine whether a three-year guarantee at room temperature is possible.

[0137] 10. Comparison of phosphate buffer solution samples and citrate buffer solution samples Samples A2 (content at time of manufacture: 0.4%, guaranteed free chlorine concentration: 50 mg / L) and B2 (content at time of manufacture: 0.2%, guaranteed free chlorine concentration: 25 mg / L), both prepared using phosphate buffer solution, were compared, as were samples E6 (content at time of manufacture: 0.2%, guaranteed free chlorine concentration: 50 mg / L) and F6 (content at time of manufacture: 0.1%, guaranteed free chlorine concentration: 25 mg / L), both prepared using citrate buffer solution.

[0138] First, when comparing the free chlorine concentration (based on Cl = 35.45) values ​​after 6 months, between sample A2 and sample E6, both of which have a guaranteed free chlorine concentration of 50 mg / L, the measured value for sample E6 was higher, and between sample B2 and sample F6, both of which have a guaranteed free chlorine concentration of 25 mg / L, the measured value for sample F6 was higher. In both cases, the formulation using citrate buffer maintained a higher free chlorine concentration (based on Cl = 35.45) than the formulation using phosphate buffer.

[0139] Furthermore, the content (as chlorous acid (HClO2 = 68.46)) was set at twice the concentration for the formulations using phosphate buffer (samples A2 and B2) at the time of manufacture compared to the formulations using citrate buffer (samples E6 and F6), but the actual measured values ​​after six months showed almost the same value (0.12%), especially for samples A2 and E2, which are guaranteed to have a free chlorine concentration of 50 mg / L.Comparing the slopes of the regression lines, it was found that the slope was steeper for the samples prepared using phosphate buffer, confirming a tendency for the content to decrease more easily.

[0140] Figure 2 shows the change over time in the content (as chlorous acid (HClO2 = 68.46)) and free chlorine concentration (as Cl = 35.45).

[0141]

[0142] From the above results, it can be said that specimens E6 (chlorous acid content: 0.2 wt%) and F6 (chlorous acid content: 0.1 wt%), which use citrate buffer, are able to maintain higher values ​​for both free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)) than specimens A2 (chlorous acid content: 0.4 wt%) and B2 (chlorous acid content: 0.2 wt%), which use phosphate buffer, and it is believed that there is a very high possibility that long-term stability (3 years) can be ensured at room temperature.

[0143] For quality with a chlorous acid content of 0.1±0.1% (HClO2 = 68.46) and a free chlorine concentration of 25mg / L or more, by using a citrate buffer solution at a liquid ratio of chlorous acid water to citrate buffer solution between 1:4 and 1:19, the product can withstand accelerated testing at 40°C±2°C, guaranteeing its scientific quality for six months. This means that it will last for three years at room temperature.

[0144] (Example 2: Examination of formulations for high-concentration hypochlorous acid water preparations) A re-examination was conducted to find formulations that could improve the stability of hypochlorous acid water preparations, which are currently the mainstay of hypochlorous acid water preparations sold, with a content at the time of manufacture of 8000 ppm (0.8% by weight) (as hypochlorous acid (HClO2 = 68.46)) / free chlorine concentration (as Cl = 35.45) of 200 mg / L or more, with the aim of identifying formulations that can be guaranteed for a period of one year or more (ideally, three years) at room temperature.

[0145] 1) Test method - Reexamination of buffer solutions Chlorous acid water was diluted using the buffer solutions shown in the table below to prepare chlorous acid water formulations with a content (as chlorous acid (HClO2 = 68.46)) of 8000 ppm at the time of manufacture and a free chlorine concentration (as Cl = 35.45) of 200 mg / L or more, and approximately 100 g of each was filled into a container. These were stored at 40°C, and unopened samples were opened and measurements were performed on each measurement day.

[0146]

[0147] Over-preparation: The buffer solution shown in the table below was used to dilute the chlorous acid solution to a content of 12,000 ppm (1.2% by weight) of chlorous acid (HClO2 = 68.46) at the time of manufacture, and a free chlorine concentration (Cl = 35.45) of 200 mg / L or more. Approximately 100 g of each solution was filled into a container. This was stored at 40°C, and unopened samples were opened and measured on each measurement day.

[0148]

[0149] *How to prepare buffer solution

[0150] 2) Test results: Reexamination of buffer solution

[0151]

[0152] Over-preparation

[0153] 3) Discussion (Summary) For hypochlorous acid water preparations with a content of 8000 ppm at the time of manufacture (as hypochlorous acid (HClO2 = 68.46)), in test group (1) where the current formulation of 0.1 mol / L phosphate buffer (pH 5.0) was used, the free chlorine concentration (as Cl = 35.45) fell below 200 mg / L from 60 to 90 days after storage at 40°C, and even when the concentration of the phosphate buffer was reduced (test groups (2) and (3)), the period during which the free chlorine concentration (as Cl = 35.45) remained above 200 mg / L did not extend.

[0154] ​On the other hand, it was confirmed that in test area (4), which used 0.05% citrate buffer solution (pH 5.0), the free chlorine concentration (as Cl = 35.45) could be maintained at 200 mg / L or higher for up to 120 days (estimated to be equivalent to 2 years at room temperature) when stored at 40°C. Furthermore, when the content (as chlorous acid (HClO2 = 68.46)) of test area (1), which uses the current formulation, was compared with that of test area (4), which used this citrate buffer solution, it was found that test area (4) not only maintained the free chlorine concentration (as Cl = 35.45) but also maintained a high content (as chlorous acid (HClO2 = 68.46)).

[0155] However, in the test group using phosphate buffer, the pH remained within the range of 4.0 to 6.0, which is the pH standard set for current chlorous acid water formulations, but in the test group using citrate buffer, the pH, which was adjusted to around 5.0 during manufacturing, temporarily rose to the pH 7 range over time, falling outside the current pH standard for chlorous acid water formulations. The changes over time in free chlorine concentration (as Cl = 35.45), content (as chlorous acid (HClO2 = 68.46)), and pH (at 100%) are shown in Figures 3-1 to 3-3, respectively.

[0156] In the case of citrate buffer, when the concentration was set to 0.03% or less, the free chlorine concentration (as Cl = 35.45) was below 200 mg / L on the 60th day after storage at 40 ° C. This indicates that reducing the buffer concentration does not lead to maintaining the free chlorine concentration (as Cl = 35.45) of the hypochlorous acid water preparation. Furthermore, since no cases have been confirmed in which the citrate buffer concentration was set higher than 0.05%, in order to confirm the appropriate concentration of citrate buffer, 0.075% (test area (13)) and 0.1% (test area (14)) were added. In addition, by combining citrate and phosphate, it is thought that the free chlorine concentration (as Cl = 35.45) and content (as hypochlorous acid (HClO2 = 68.46)) can be maintained, and the pH value can also be kept within the current standard range. Therefore, a citrate-phosphate buffer (test area (15)) was added and confirmed.

[0157] Next, for hypochlorous acid water preparations that were over-charged and had a content (as hypochlorous acid (HClO2 = 68.46)) of 12,000 ppm at the time of manufacture, the free chlorine concentration (as Cl = 35.45) started at a value of 300 mg / L or higher at the time of manufacture, and when stored at 40°C, the period during which the free chlorine concentration (as Cl = 35.45) remained at 200 mg / L or higher was confirmed.When the content (as hypochlorous acid (HClO2 = 68.46)) at the time of manufacture was set to 12,000 ppm, the free chlorine concentration (as Cl = 35.45) remained at 200 mg / L or higher until the 120th day (equivalent to 2 years at room temperature) when stored at 40°C, regardless of the type of buffer solution.

[0158] However, in the case of phosphate buffer, the free chlorine concentration (assuming Cl = 35.45) fell below 200 mg / L by the 150th day, failing to meet the 180-day storage period at 40°C, which is expected to be equivalent to three years at room temperature. On the other hand, in the test group using citrate buffer, the free chlorine concentration (assuming Cl = 35.45) remained above 200 mg / L until the 150th day. The changes over time in free chlorine concentration (assuming Cl = 35.45), content (assuming chlorous acid (HClO2 = 68.46)), and pH (at 100%) are shown in Figures 4-1 to 4-3, respectively.

[0159] Furthermore, as with the reexamination test of the buffer solution, this test using excessive amounts of citrate buffer could not confirm what would happen if the concentration of the citrate buffer was higher than 0.05%, so in order to confirm the appropriate concentration of citrate buffer, 0.075% (test area (13)) and 0.1% (test area (14)) were added. Furthermore, it was thought that by combining citrate and phosphate, the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)) could be maintained while also keeping the pH within the current standard range, so a citrate-phosphate buffer (test area (15)) was added and confirmed.

[0160] Based on the above results, if the pH specification range of the hypochlorous acid solution formulation is changed, it will be possible to use a citrate buffer solution with a concentration of 0.05% or higher without overfilling, which will ultimately extend the warranty period. However, it is necessary to separately confirm whether changing the buffer base will affect the effectiveness of the hypochlorous acid solution.

[0161] For hypochlorous acid water formulations with a content of 8000 ppm (as hypochlorous acid (HClO2 = 68.46)) at the time of manufacture, the results for 120 days after storage at 40°C were obtained for three prototypes using "0.075% citrate buffer solution (test group (13))", "0.1% citrate buffer solution (test group (14))", and "citric acid / phosphate buffer solution (test group (15))".

[0162] As a result, for chlorous acid water formulations with a manufacturing content (as chlorous acid (HClO2 = 68.46)) of 8000 ppm, the prototypes using "0.075% citrate buffer (Test Group (13))" and "0.1% citrate buffer (Test Group (14))" maintained free chlorine concentrations (as Cl = 35.45) of 241 mg / L and 259 mg / L, respectively, even after 120 days, indicating that sufficient concentrations were maintained. However, the prototype using "citric acid / phosphate buffer (Test Group (15))" showed a free chlorine concentration (as Cl = 35.45) of 198 mg / L, below 200 mg / L, after 120 days, indicating that "citric acid / phosphate buffer (Test Group (15))" was not suitable.

[0163] From these results, when considering the citric acid concentration suitable for a buffer solution to be used in hypochlorous acid water preparations, which have a manufacturing content (as hypochlorous acid (HClO2 = 68.46)) of 8000 ppm, it was confirmed that for the "0.05% citrate buffer solution (test group (4))," the free chlorine concentration (as Cl = 35.45) on the 120th day was 215 mg / L, remaining above 200 mg / L, but falling below 200 mg / L on the 150th day. However, in contrast to this, for "0.075% citrate buffer solution (test area (13))" and "0.1% citrate buffer solution (test area (14))," although confirmation has only been possible up to the 120th day at present, the free chlorine concentration (based on Cl = 35.45) on the 120th day was more than 20 mg / L higher than for "0.05% citrate buffer solution (test area (4))," and it is certain that the free chlorine concentration (based on Cl = 35.45) will be maintained at a value of 200 mg / L or more for a longer period of time than for "0.05% citrate buffer solution (test area (4))."

[0164] However, since the content (as chlorous acid (HClO2 = 68.46)) of "0.1% citrate buffer solution (test area (14))" after 120 days at 40°C was "3951 ppm," which is below 4000 ppm, it is estimated that the supply of free chlorine concentration (as Cl = 35.45) from the content (as chlorous acid (HClO2 = 68.46)) of "0.1% citrate buffer solution (test area (14))" will be disrupted at an early stage in the future. Therefore, it is necessary to observe the progress a little more to determine whether "0.075% citrate buffer solution (test area (13))" or "0.1% citrate buffer solution (test area (14))" will maintain the free chlorine concentration (as Cl = 35.45) for a longer period of time.

[0165] Furthermore, the buffer solution to be used in hypochlorous acid water preparations, whose content (as hypochlorous acid (HClO2 = 68.46)) at the time of manufacture was set to 8000 ppm, could be narrowed down to either "0.075% citrate buffer solution" or "0.1% citrate buffer solution." In addition, when the concentration of citrate buffer is higher than 0.1%, the rate of decrease in content (as chlorous acid (HClO2 = 68.46)) tends to be faster as the concentration of citrate buffer increases. Under conditions of concentrations higher than 0.1%, it is predicted that the content (as chlorous acid (HClO2 = 68.46)) will decrease at a faster rate than with 0.1% citrate buffer. Since it is presumed that the stagnation of the supply from content (as chlorous acid (HClO2 = 68.46)) to free chlorine concentration (as Cl = 35.45) will occur more quickly, it is thought that the effect of maintaining free chlorine concentration (as Cl = 35.45) over a long period of time cannot be expected.

[0166] Content (as chlorous acid (HClO2=68.46)): Buffer solutions thought to be suitable for 8000 ppm product (as of D+120) (1) 0.075% citrate buffer solution / initial pH 5.0 (2) 0.1% citrate buffer solution / initial pH 5.0 (3) 0.075-0.1% citrate buffer solution / initial pH 5.0 (confirmation required) Figure 5 shows the change in the residual rate of citrate buffer solution concentration (%) [initial pH 5.0] and content (as chlorous acid (HClO2=68.46)).

[0167] Next, for hypochlorous acid water preparations with an over-charged content of 12,000 ppm (as hypochlorous acid (HClO2 = 68.46)) at the time of manufacture, the "prototypes using 0.01% to 0.05% citrate buffer (test groups (10), (11), (12))" all maintained a free chlorine concentration (as Cl = 35.45) of 200 mg / L or more up to 150 days after storage at 40°C, but the "prototype using 0.05% citrate buffer (test group (10))" showed a free chlorine concentration (as Cl = 35.45) of 196 mg / L on the 180th day, falling below the standard of 200 mg / L. The reason why the free chlorine concentration (as Cl = 35.45) for the "0.05% citrate buffer solution (Test Group (10))" fell below 200 mg / L is that the decrease in free chlorine concentration (as Cl = 35.45) from Day 150 to Day 180 for the "0.05% citrate buffer solution (Test Group (10))" clearly increased compared to the previous trend. Moreover, after storage at 40°C, the content (as chlorous acid (HClO2 = 68.46)) on Day 180 was 3440 ppm, less than 30% of the value at the time of manufacture. Based on these results, we speculate that the decrease in content (as chlorous acid (HClO2 = 68.46)) was due to a halt (delay) in the supply of free chlorine (as Cl = 35.45). The time course of the residual rate of the content (as chlorous acid (HClO2 = 68.46)) and the free chlorine concentration (as Cl = 35.45) in test area (10) is shown in Figure 6.

[0168] Therefore, it was confirmed that the free chlorine concentration (assuming Cl = 35.45): 200 mg / L or more can be maintained up to 180 days after storage at 40°C with "0.01% citrate buffer solution (test group (12))" or "0.03% citrate buffer solution (test group (11))".

[0169] Content (as chlorous acid (HClO2=68.46)): 12000 ppm Buffer solutions that are considered suitable for this product: (1) 0.01% citrate buffer solution / initial pH 5.0 (2) 0.03% citrate buffer solution / initial pH 5.0 (3) 0.075% or more citrate buffer solution / initial pH 5.0 *As of D+120

[0170] (When hypochlorous acid water is used as the main ingredient) Based on the above, the formulation and manufacturing specifications when hypochlorous acid water is used as the main ingredient are presented below. Hypochlorous acid water

[0171] <Composition> α) Hypochlorous acid solution (undiluted product) *1: The values ​​of X and Y are calculated and mixed so that the content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture is 8800 ppm and the free chlorine concentration (as Cl = 35.45) is 200 mg / L or more. *2: Citrate buffer solution (initial pH should be set to 5.0) Note: Use either 0.075% or 0.1% buffer.

[0172] <Manufacturing standards>

[0173] (When chlorous acid = chlorine peroxide radical (chlor·) is used as the main raw material) Next, chlorous acid = chlorine peroxide radical (ClOO·) was used as the raw material and diluted with a pH 5.0 citrate buffer solution (0.075% or 0.10%) to produce a prototype chlorous acid water formulation with a content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture of 8000 ppm, and it was confirmed whether the free chlorine concentration (as Cl = 35.45) was 200 mg / L or more, the content (as chlorous acid (HClO2 = 68.46)) was 8800 ± 800 ppm, and the pH (at 100%) was of the same quality as the prototypes (13) and (14) in the above test.

[0174] When calculating the compounding ratio of chlorous acid = chlorine peroxide radical (ClOO·), the set value of the free chlorine concentration (assuming Cl = 35.45) was 400 mg / L or 450 mg / L, and the obtained value was rounded to the fourth decimal place, with the first three decimal places considered valid.

[0175] As a result, it was found that prototypes using "pH 5.0 citrate buffer solution (0.075% or 0.10%)" can meet the values ​​of free chlorine concentration (as Cl = 35.45): 200 mg / L or more, and content (as chlorous acid (HClO2 = 68.46)): 8800 ± 800 ppm, even in prototypes based on a formulation in which the set value of free chlorine concentration (as Cl = 35.45) was adjusted to 400 mg / L. However, the actual measured pH (at 100%) was low, at 4.30 to 4.43, which was found to be significantly different from the initial pH values ​​(4.93, 4.88) of test plots (13) and (14) in the above test. It was found that when a hypochlorous acid water formulation with a content of 8000 ppm (as hypochlorous acid (HClO2 = 68.46) at the time of manufacture was used, the amount of this hypochlorous acid = chlorine peroxide radical (ClOO·) added increased, and the pH was pulled by the pH of the hypochlorous acid = chlorine peroxide radical (ClOO·).

[0176] Therefore, a citrate buffer solution with a pH of 5.5 or 6.0 was used to again produce a hypochlorous acid solution formulation with a content of 8000 ppm (as hypochlorous acid (HClO2 = 68.46) at the time of manufacture). At this time, the set value for the free chlorine concentration (as Cl = 35.45) was 400 mg / L, and the obtained values ​​were rounded to the fourth decimal place, with the values ​​up to the third decimal place being valid.

[0177] As a result, when "citric acid buffer solution of pH 5.5" was used, the pH value of the prototype was 4.72 to 4.78, and when "citric acid buffer solution of pH 6.0" was used, the pH value of the prototype was 5.10 to 5.17. It was found that in order to adjust the pH to the same level as test area (13) and test area (14) using chlorous acid = chlorine peroxide radical (ClOO.) as the raw material, it is necessary to raise the pH of the buffer solution to around 6.0.

[0178] [Prototype results from chlorous acid = chlorine peroxide radical (ClOO.)] *1: The values ​​of X and Y are calculated and mixed so that the content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture is 8800 ppm and the free chlorine concentration (as Cl = 35.45) is 200 mg / L or more. *2: Citrate buffer solution (initial pH should be set to 5.0) Note: Use either 0.075% or 0.1% buffer.

[0179] <Prototype measurement results with buffer solution pH changed>

[0180] <Composition> α) Hypochlorous acid solution (undiluted product) *1: The values ​​of X and Y are calculated and mixed so that the content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture is 8800 ppm and the free chlorine concentration (as Cl = 35.45) is 200 mg / L or more. *2: Citrate buffer solution (pH of the buffer solution should be set to 6.0) Note: Use either 0.075% or 0.1% buffer.

[0181] <Manufacturing standards>

[0182] For a hypochlorous acid water formulation with a content (as hypochlorous acid (HClO2 = 68.46)) of 8000 ppm at the time of manufacture, the results were obtained for two prototypes using "0.075% citrate buffer (Test group (13))" and "0.1% citrate buffer (Test group (14))" after 180 days of storage at 40°C.

[0183] As a result, it was found that both prototypes maintained a free chlorine concentration (assuming Cl = 35.45) of 200 mg / L or more up to 180 days after storage at 40°C. Therefore, in order to confirm which of these prototype formulations was better, an approximation curve of the free chlorine concentration (assuming Cl = 35.45) was created and the number of days until the free chlorine concentration (assuming Cl = 35.45) reached 200 mg / L was calculated. When 0.1% citrate buffer solution (Test Group (14)) was used as the buffer solution, the free chlorine concentration (assuming Cl = 35.45) remained at 200 mg / L up to 202 days after storage at 40°C, but with 0.075% citrate buffer solution (Test Group (13)), the result was 177 days after storage at 40°C, which is short of the 180-day period after storage at 40°C, which is considered to be equivalent to 3 years at room temperature (Figure 7).

[0184]

[0185] Based on the above results, we have determined that 0.1% citrate buffer (pH 5.0) is the most suitable buffer solution for preparing chlorous acid water formulations with a manufacturing content (as chlorous acid (HClO2 = 68.46)) of 8000 ppm. However, based on actual measurements, both the prototypes using 0.075% citrate buffer (pH 5.0) and 0.1% citrate buffer (pH 5.0) maintained a free chlorine concentration (as Cl = 35.45) of 200 mg / L or higher up to 180 days after storage at 40°C, suggesting that the concentration error within the range of 0.075% to 0.1% is within the acceptable range.

[0186] This product, which has the same quality as "Chlorus Acid N Barrier," contains 8,000 ppm (0.8% by weight) of chlorous acid (HClO2 = 68.46) and a free chlorine concentration of over 200 mg / L, was blended with 0.01-0.1% citrate buffer. The results confirmed that the free chlorine concentration (as Cl = 35.45) remained above 200 mg / L for up to 120 days (equivalent to two years at room temperature) after storage at 40°C. Furthermore, when the content (as chlorous acid (HClO2 = 68.46)) of the test group containing the citrate buffer was compared with that of the current phosphate buffer, the test group containing the citrate buffer not only maintained a significantly higher free chlorine concentration (as Cl = 35.45), but also maintained a higher content (as chlorous acid (HClO2 = 68.46)).

[0187] In addition, despite the harsh conditions of storing an over-prepared hypochlorous acid solution (12,000 ppm (1.2 wt%) of hypochlorous acid (HClO2 = 68.46) at the time of manufacture) at 40°C, the free chlorine concentration (based on Cl = 35.45) at the time of manufacture started at a value of over 300 mg / L, and when the period during which the free chlorine concentration (based on Cl = 35.45) was maintained at 200 mg / L or more was confirmed, it was found that this could be maintained for up to 120 days (equivalent to 2 years at room temperature), and that by using it in combination with a citrate buffer solution, it was possible to maintain an even higher free chlorine concentration (based on Cl = 35.45).

[0188] (Example 3: Study on the formulation of hypochlorous acid water preparation (content at time of manufacture: 500 ppm (0.05% by weight)) The hypochlorous acid water preparation of this concentration has the representative product name "Care for Hands" and is intended to be used as is for sterilizing food ingredients, disinfecting objects (hands), etc.

[0189] The content at the time of manufacture (as chlorous acid (HClO2 = 68.46)) 500 ppm / free chlorine concentration (as Cl = 35.45): 10 mg / L or more. We conducted a re-examination of the formulation that is expected to improve the stability of hypochlorous acid water formulations, with the aim of identifying a formulation that can be guaranteed for a period of one year or more (ideally, three years) at room temperature.

[0190] (Test method) Hypochlorous acid water formulations were prepared under the test conditions shown in the table below, and approximately 100 g of each was filled into each container. These were stored at 40°C, and unopened samples were opened and measured on each measurement day.

[0191] The main raw material used was chlorous acid = chlorine peroxide radical (ClOO·), and we decided to only examine direct blending.

[0192]

[0193] *Method for preparing buffer solutions Each buffer solution was prepared according to the following formulation.

[0194] (Test results)

[0195] [Measurement results of main ingredients] Note: For 500 ppm products, the free chlorine concentration is set to 20 mg / L. ※ The compounding ratio was calculated as above, and the third decimal place was rounded up or down, with the second decimal place being considered valid. *Based on the results of a trial run by the Quality Assurance Department (product with a content of 8000 ppm at the time of manufacture), a reduction in free chlorine concentration of approximately 40 to 60% was confirmed.

[0196] The content (as chlorous acid (HClO2 = 68.46)) and free chlorine concentration (as Cl = 35.45) are shown in Figures 8-1 and 8-2: Content (as chlorous acid (HClO2 = 68.46)) <Regression line> Cont: Y = -0.003Ln(X) + 6.279 Test (1): Y = -0.004Ln(X) + 6.263 Test (2): Y = -0.005Ln(X) + 6.285 Test (3): Y = -0.005Ln(X) + 6.297 Free chlorine concentration (as Cl = 35.45) <Regression line> Cont: Y = -0.003Ln(X) + 3.089 Test (1): Y = -0.004Ln(X) + 3.558 Test (2): Y=-0.004Ln(X)+3.417 Test (3): Y=-0.004Ln(X)+3.427

[0197] Discussion (Summary) Using chlorous acid = chlorine peroxide radical (ClOO·) as a raw material, a chlorous acid water formulation with a content of 500 ppm (as chlorous acid (HClO2 = 68.46)) at the time of manufacture was prepared using the following: Control: 0.1 mol / L phosphate buffer solution (pH 5.0), Test (1): 0.1 mol / L phosphate buffer solution (pH 4.5), Test (2): 0.075% citrate buffer solution (pH 5.0), Test (3): 0.1% citrate buffer solution (pH 5.0), and a storage test was conducted at 40°C.

[0198] As a result, it was confirmed that whichever buffer solution was used, the free chlorine concentration (assuming Cl = 35.45) could be maintained at 10 mg / L or higher up to 180 days after storage at 40°C. It was also confirmed that the prototypes using either buffer solution were formulated to be able to maintain a free chlorine concentration (assuming Cl = 35.45) of 10 mg / L or higher for three years at room temperature.

[0199] However, when calculating the period during which the free chlorine concentration (assuming Cl = 35.45) was maintained at 10 mg / L or higher from the regression line, it was 242 days in the Control group, while it was more than 290 days in the Test (1) to Test (3) groups, which means that it could be maintained for approximately 50 days longer than the Control group.In terms of the effect of maintaining the free chlorine concentration (assuming Cl = 35.45), it was found that the pH 4.5 phosphate buffer (Test (1) group), 0.075% citrate buffer (Test (2) group), or 0.1% citrate buffer (Test (3) group) were formulations that could maintain the free chlorine concentration (assuming Cl = 35.45) for a longer period than the prototype based on the formulation using the current pH 5.0 phosphate buffer.

[0200] On the other hand, with regard to the content (as chlorous acid (HClO2 = 68.46)), the number of days for which the content (as chlorous acid (HClO2 = 68.46)) calculated from the regression line was maintained at 250 ppm or above gradually decreased in the order of Cont > Test (1) > Test (2) > Test (3), indicating a tendency for the test group using phosphate buffer to be more likely to maintain the content (as chlorous acid (HClO2 = 68.46)) than the citrate buffer.

[0201] Number of days each concentration is maintained (40℃) *Calculated from the regression line

[0202] From the above results, it was found that for products with a content of 500 ppm at the time of manufacture (as hypochlorous acid (HClO2 = 68.46)), it is highly likely that the desired quality assurance period (equivalent to 3 years at room temperature) can be set even with the current formulation. Therefore, from the perspective of maintaining the free chlorine concentration (as Cl = 35.45) for a longer period, it can be clearly assumed that Test (1) will be advantageous in the future.

[0203] Therefore, Test (1) group: A prescription using "0.1 mol / L phosphate buffer (pH 4.5)" is described below.

[0204] *1: The values ​​of X and Y are calculated and mixed so that the content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture is 550 ppm and the free chlorine concentration (as Cl = 35.45) is 10 mg / L or more. *2: Phosphate buffer solution (pH of the buffer solution should be set to 4.5) *3: The total was calculated to be 100% based on the aforementioned buffer solution formulation. It is necessary to confirm whether the pH actually reaches around 4.5.

[0205]

[0206] For products containing 500 ppm (0.05% by weight) of chlorous acid (HClO2 = 68.46) at the time of manufacture, phosphate buffer solution was better able to maintain a free chlorine concentration of 10 mg / L or more for 180 days (guaranteed for approximately 3 years at room temperature) under the harsh environment of 40°C than citrate buffer solution.

[0207] (Example 4: Examination of formulation of hypochlorous acid water preparation (content at time of manufacture: 4000 ppm (0.4% by weight))) A formulation was created in the early stages of development of "hypochlorous acid water," and the guaranteed content at time of manufacture is 4000 ppm (guaranteed: 3000 ppm) (hypochlorous acid (HClO2 = 68.46)) / free chlorine concentration (as Cl = 35.45): 100 mg / L or more. A re-examination of the formulation was carried out with the aim of identifying a formulation that can be guaranteed for a period of one year or more (ideally, three years) at room temperature.

[0208] (Test method) Hypochlorous acid water formulations were prepared under the test conditions shown in the table below, and approximately 100 g of each was filled into each container. These were stored at 40°C, and unopened samples were opened and measured on each measurement day.

[0209] The main raw material used was chlorous acid = chlorine peroxide radical (ClOO·), and we decided to only examine direct blending.

[0210] *Method for preparing buffer solutions 0.075% citrate buffer solution and 0.1% citrate buffer solution were prepared according to the following formulation.

[0211] (Test results) [Measurement results of main raw materials] Note: For 4000 ppm products, the free chlorine concentration setting is 200 mg / L. ※ The compounding ratio was calculated as above, and the third decimal place was rounded up or down, with the second decimal place being considered valid. *Based on the results of a trial run by the Quality Assurance Department (product with a content of 8000 ppm at the time of manufacture), a reduction in free chlorine concentration of approximately 40 to 60% was confirmed.

[0212] [Initial results of the formulation] *1: In order to adjust the pH of the prototype to around 5, the pH of the citrate buffer was adjusted to 5.5.

[0213] [Saved test results]

[0214] Discussion (Summary) Using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material, a prototype was produced with a content of 4000 ppm at the time of production (as chlorous acid (HClO2 = 68.46)). The amount of chlorous acid = chlorine peroxide radical (ClOO·) was calculated from the free chlorine concentration of chlorous acid = chlorine peroxide radical (ClOO·) (assuming Cl = 35.45) as a set value of 200% (200 mg / L) of the prototype's specification value (100 mg / L). The pH of the citrate buffer was adjusted to pH 5.5, and prototypes were produced using amounts of 0.075% and 0.1%.

[0215] As a result, the initial free chlorine concentration (assuming Cl = 35.45) for all prototypes was 140-145 mg / L, approximately 30% lower than the set value, and the content at the time of manufacture (as chlorous acid (HClO2 = 68.46)) met the standard value of 100 mg / L or more for the free chlorine concentration (assuming Cl = 35.45) of a 4000 ppm product.

[0216] Regarding pH, the initial pH of the prototypes using citrate buffer was 5.13 for 0.075% citrate buffer and 5.03 for 0.1% citrate buffer, resulting in a pH of around 5.0.

[0217] Therefore, a storage test was conducted on these prototypes at 40°C. In the Control group, which was prepared using 0.1 mol / L phosphate buffer (pH 5.0) equivalent to the current product, it was found that the content (as chlorous acid (HClO2 = 68.46)) fell below 3000 ppm on the 60th day, and the free chlorine concentration (as Cl = 35.45) fell below 100 mg / L on the 150th day.

[0218] On the other hand, in Test-A, which used 0.075% citrate buffer (pH 5.5), and Test-B, which used 0.1% citrate buffer (pH 5.5), the content (as chlorous acid (HClO2 = 68.46)) remained above 3000 ppm until the 120th day, and even after 150 days, the free chlorine concentration (as Cl = 35.45) remained above 100 mg / L. From this, it was clear that the use of citrate buffer can maintain both the content (as chlorous acid (HClO2 = 68.46)) and the free chlorine concentration (as Cl = 35.45) for a longer period than the control group. However, in terms of pH, the Control group, which was prepared using 0.1 mol / L phosphate buffer (pH 5.0), equivalent to the current product, maintained a pH of 4.75 to 5.34, within the pH 5.5 ± 1.0 (pH 4.5 to 6.5) range, until the 150th day. However, in the test group using citrate buffer, the pH exceeded 6.5 after about 60 days. Based on these results, although the pH deviated significantly from the pH range of the current product, both the content (as chlorous acid (HClO2 = 68.46)) and the free chlorine concentration (as Cl = 35.45) were maintained for a significantly longer period than the current product. For this reason, we believe it would be better to change the product with a manufacturing content of 4000 ppm (as chlorous acid (HClO2 = 68.46)) from the current 0.1 mol / L phosphate buffer (pH 5.0) to a citrate buffer.

[0219] When using a citrate buffer solution, to determine whether a 0.075% or 0.1% citrate buffer solution concentration is better, the natural logarithms of each solution were plotted, and the number of days during which the content (as chlorous acid (HClO2 = 68.46)) was maintained at 3000 ppm and the number of days during which the free chlorine concentration (as Cl = 35.45) was maintained at 100 mg / L were calculated from the resulting straight line approximation.The calculation shows that although the free chlorine concentration (as Cl = 35.45) is maintained for a longer period with 0.1% solution than with 0.075%, both solutions maintain a free chlorine concentration (as Cl = 35.45) of 100 mg / L or higher for 180 days or more of storage at 40°C. On the other hand, in terms of the content (as hypochlorous acid (HClO2 = 68.46)), the 0.075% citrate buffer solution maintained a content of 3000 ppm or more for a longer period than the 0.1% solution, and it was found that the only test area where this was maintained for 120 days at 40°C (equivalent to 720 days at room temperature) was the test area using 0.075% citrate buffer solution.

[0220] Based on the above results, it has been determined that a 0.075% citrate buffer solution is suitable for use in a formulation with a 4000 ppm content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture to guarantee a content (as chlorous acid (HClO2 = 68.46)) specification of 3000 ppm.

[0221] However, since the free chlorine concentration (as Cl = 35.45) in the test area was maintained at 100 mg / L or more, the test was continued until 180 days. The content (as chlorous acid (HClO2 = 68.46)) and free chlorine concentration (as Cl = 35.45) are shown in Figures 24-1 and 24-2:

[0222] <Final report / D+180 days later> As of the previous interim report, it was already known that the only test group that had been able to maintain a [content (as chlorous acid (HClO2 = 68.46))] of 3000 ppm or higher for 120 days at 40°C (equivalent to 720 days at room temperature) was the test group using 0.075% citrate buffer (Test-A), and a conclusion had been reached regarding the maintenance of [content (as chlorous acid (HClO2 = 68.46)]. However, the free chlorine concentration (as Cl = 35.45) was maintained at 100 mg / L or higher in both test groups (Test-A and Test-B) using 0.075% and 0.1% citrate buffer. Therefore, the storage test was continued to confirm the value of the free chlorine concentration (as Cl = 35.45).

[0223] As a result, it was found that in both test sections (Test-A, Test-B), the free chlorine concentration (assuming Cl = 35.45) was maintained at 100 mg / L or more up to 180 days after storage at 40°C. Based on the actual measured values ​​of the free chlorine concentration (assuming Cl = 35.45) in this test, it was found that there is a high possibility that this free chlorine concentration (assuming Cl = 35.45) can be maintained at 100 mg / L or more for a period equivalent to three years at room temperature.

[0224] *1: The values ​​of X and Y are calculated and mixed so that the content (as chlorous acid (HClO2 = 68.46)) at the time of manufacture is 4400 ppm and the free chlorine concentration (as Cl = 35.45) is 100 mg / L or more. *2: Citrate buffer solution (pH of the buffer solution should be set to 5.5)

[0225]

[0226] When the optimal conditions for citrate buffer were investigated using a hypochlorous acid solution formulation with a chlorous acid content of 4000 ppm (0.4% by weight) (HClO2 = 68.46) at the time of manufacturing, it was found that the optimal concentration of citric acid capable of maintaining a chlorous acid content of 3000 ppm (HClO2 = 68.46) and a free chlorine concentration (Cl = 35.45) of 10 mg / L for 180 days (3 years at room temperature) under the harsh conditions of 40°C was between 0.01% and 0.1%, with 0.075% being the most preferable.

[0227] (Example 5: Storage test of low-concentration hypochlorous acid water formulation (200 ppm (0.02 wt %) product)) By comparing a prototype (hypochlorous acid water formulation) made using hypochlorous acid = chlorine peroxide radical (ClOO.) as a raw material with a prototype (hypochlorous acid water formulation) made using hypochlorous acid water as a raw material, it was confirmed whether the reproducibility of the results of the storage test would be confirmed, and whether differences in the raw materials, formulation, and method would result in differences in the quality of the finished products and their subsequent changes over time (whether the free chlorine concentration (assuming Cl = 35.45) could be maintained for a longer period of time).

[0228] <Contents of the study> [1] Confirmation of reproducibility of hypochlorous acid water A prototype was made using hypochlorous acid water as the raw material and phosphate buffer solution, and the quality of the finished product and subsequent changes over time were confirmed to see whether the same trends as in the storage test conducted previously were observed.

[0229] [2] Differences in raw materials used in hypochlorous acid water preparations (200 ppm product) By comparing a prototype (hypochlorous acid water preparation) made using hypochlorous acid = chlorine peroxide radical (ClOO.) as a raw material with a prototype (hypochlorous acid water preparation) made using hypochlorous acid water, we confirmed whether there were any differences in the finished product due to the difference in raw materials and whether any differences appeared in its changes over time.

[0230] [3] Formulation and method of hypochlorous acid water preparation (200 ppm product) When hypochlorous acid = chlorine peroxide radical (ClOO·) is used as a raw material, we checked whether there are any differences in the effects of the formulation and method, and whether there are any differences in the changes over time, when hypochlorous acid = chlorine peroxide radical (ClOO·) is directly added (direct formulation) or when it is mixed with GB chlorine dioxide water to make hypochlorous acid water and then added (indirect formulation).

[0231]

[0232] 2. Purpose To create prototypes using 0.1 mol / L phosphate buffer solution with a pH of 4.5 for examining the above [1] to [3] using chlorous acid = chlorine peroxide radical (ClOO·) or chlorous acid water as a raw material, and to confirm the quality of the finished product of each prototype and the change in quality over time during storage tests, and then compare each prototype to confirm the reproducibility of the results of previous storage tests, and to confirm whether differences in raw materials, formulations, and methods (direct and indirect blending) result in differences in the quality of the finished product and its change over time (whether the free chlorine concentration (assuming Cl = 35.45) can be maintained for a longer period of time).

[0233] 3. Samples and raw materials

[0234] Equipment and instruments: electronic balance, pH meter, measuring cylinder, stirrer, stirring bar, beaker, Erlenmeyer flask with stopper, standard hydrometer, spectrophotometer, quartz cell

[0235] Reagents: Potassium iodate, sodium thiosulfate pentahydrate, potassium iodide, sulfuric acid, starch (soluble), sodium azide, sodium carbonate, hydrochloric acid, potassium hydrogen phthalate, potassium monophosphate, sodium tetraborate decahydrate, DPD reagent

[0236] 4. Method (1) Prepare chlorous acid = chlorine peroxide radical (ClOO·). When using chlorous acid = chlorine peroxide radical (ClOO·) for testing, the following specification range is used as a guideline, so the pH, [content (as chlorous acid (HClO2 = 68.46))], and [free chlorine concentration (as Cl = 35.45)] of the prepared chlorous acid = chlorine peroxide radical (ClOO·) were measured to confirm whether they fell within the following specification range.

[0237]

[0238] *1) Value obtained by the glass electrode method *2) Value obtained by the iodometric reduction titration method (unit: ppm) *3) Value obtained by the colorimetric method (DPD method) (unit: mg / L)

[0239] (2) Prepare 0.1 mol / L phosphate buffer solution (pH 4.5) according to the following formula:

[0240] (3) Using the 0.1 mol / L phosphate buffer solution (pH 4.5) prepared in (2), a prototype using hypochlorous acid water as a raw material (hypochlorous acid water preparation) and a prototype using hypochlorous acid = chlorine peroxide radical (ClOO ) as a raw material (hypochlorous acid water preparation) are prepared according to the following formulation.

[0241] Furthermore, in this test, the differences in the raw materials used between a prototype using hypochlorous acid water as a raw material and a prototype using hypochlorous acid = chlorine peroxide radical (ClOO·) as a raw material were compared, as well as the differences in the formulation and method between a prototype in which hypochlorous acid = chlorine peroxide radical (ClOO·) was directly blended and a prototype in which it was indirectly blended. Therefore, in order to make the final concentrations consistent, the blending rate (%) of 0.1 mol / L phosphate buffer (pH 4.5) was adjusted to the same level as for the prototype using hypochlorous acid water as a raw material.

[0242] [Hydrochlorous acid water preparation containing chlorous acid water] Formulation of chlorous acid water preparation containing chlorous acid water

[0243] Formula for calculating the blending ratio [hypochlorous acid water]

[0244] ・Concentration of hypochlorous acid water: XX = [Free chlorine concentration setting: 8 (mg / L)] (*5) * 102%) / [Free chlorine concentration of hypochlorous acid water (mg / L)]

[0245] ・Chlorine dioxide water blending ratio: YY = ([Content setting value: 275 (ppm)] * 102 (%)) - [Chlorous acid water content (ppm)] * X (%)) / [Chlorine dioxide water content (ppm)]

[0246] ・Composition ratio of 0.1 mol / L phosphate buffer (pH 4.5): ZZ = 102 (%) - [X (%) + Y (%)]

[0247] *5) The set value for the [free chlorine concentration (assuming Cl = 35.45)] for formulations using hypochlorous acid water is set in advance to a value that is expected to be equivalent to the [free chlorine concentration (assuming Cl = 35.45)] of the finished prototype (hypochlorous acid water formulation) using hypochlorous acid = chlorine peroxide radical (ClOO·).

[0248] [Chlorous acid = chlorine peroxide radical (ClOO·) is directly added as a prototype of a hypochlorous acid water preparation (direct blending)] Direct blending: A formulation of hypochlorous acid water preparation that is directly added as a prototype of a hypochlorous acid water preparation.

[0249]

[0250] *6) The blending ratio (%) of various buffer solutions will be the same as that of the prototype (hypochlorous acid water preparation) that uses hypochlorous acid water as a raw material, and the remainder will be blended with ion-exchanged water.

[0251] Formula for calculating the blending ratio [Direct blending: chlorous acid = chlorine peroxide radical (ClOO·)]

[0252] ・The blending ratio of chlorous acid = chlorine peroxide radical (ClOO·): aa = [free chlorine concentration setting: 10 (mg / L)] (※7) * 102 (%) / [free chlorine concentration (mg / L) of chlorous acid = chlorine peroxide radical (ClOO·)]

[0253] ・Chlorine dioxide water blending ratio: bb = ([Content setting: 275 (ppm)] * 102 (%)) - [Chlorous acid = chlorine peroxide radical (ClOO.) content (ppm)] * a (%)) / [chlorine dioxide water content (ppm)]

[0254] ・Composition ratio of 0.1 mol / L phosphate buffer (pH 4.5): ZZ = 102 (%) - [X (%) + Y (%)]

[0255] ・Ion-exchange water blending ratio: cc = 102(%) - [a(%) + b(%) + Z(%)]

[0256] *7) When hypochlorous acid (chlorine peroxide radicals, ClOO·) is directly added to produce a hypochlorous acid solution (200 ppm), it has already been found that the final [free chlorine concentration (assuming Cl = 35.45)] will be just over 60% of the set value, and it has been confirmed that by setting the [free chlorine concentration (assuming Cl = 35.45)] value to 10 mg / L, the final [free chlorine concentration (assuming Cl = 35.45)] will be within the range of 5 mg / L or more.

[0257] Therefore, the set value of [free chlorine concentration (assuming Cl=35.45)] is set to [free chlorine concentration (assuming Cl=35.45)]: 10 mg / L.

[0258] [Chlorous acid = chlorine peroxide radical (ClOO·) mixed with GB chlorine dioxide water to create chlorous acid water, which is then mixed with chlorine dioxide water to create a hypochlorous acid water preparation (indirect blend)]

[0259] Indirect formulation (1): [Chlorous acid = chlorine peroxide radical (ClOO·) and GB chlorine dioxide water are mixed to form a chlorous acid water formulation.

[0260]

[0261] Formula for calculating the blending ratio [Indirect blending (1): chlorous acid = chlorine peroxide radical (ClOO·)

[0262] - Mixing ratio of chlorous acid = chlorine peroxide radical (ClOO·): α α = [Set value of free chlorine concentration: 2500 (mg / L)] (*8) * 102 (%) / [Free chlorine concentration of chlorous acid = chlorine peroxide radical (ClOO·) (mg / L)]

[0263] ・Blending ratio of chlorine dioxide water: β β = ([Set content: 50,000 (ppm)] * 102 (%)] (*8) - [Chlorous acid = chlorine peroxide radical (ClOO.) content (ppm)] * a (%)) / [chlorine dioxide water content (ppm)]

[0264] ・Ion-exchange water blending ratio: γ γ=102(%)-[α(%)+β(%)]

[0265] *8) From the results of preliminary trial production and confirmation, even when chlorous acid water is made by mixing chlorous acid = chlorine peroxide radical (ClOO·) with GB chlorine dioxide water, the resulting [free chlorine concentration (assuming Cl = 35.45)] is just over 60% of the set value. Based on this, the set value for [free chlorine concentration (assuming Cl = 35.45)] is calculated and set to a value that is expected to be approximately the same as the [free chlorine concentration (assuming Cl = 35.45)] of chlorous acid water.

[0266] Furthermore, the set value for [content (as chlorous acid (HClO2 = 68.46))] is also set to a value that is approximately the same as the actual measured value of [content (as chlorous acid (HClO2 = 68.46)]] of hypochlorous acid water, in order to match it with the [content (as chlorous acid (HClO2 = 68.46)] of hypochlorous acid water.

[0267] However, here, the set values ​​are calculated assuming that the hypochlorous acid water has a [content (as hypochlorous acid (HClO2 = 68.46))] of approximately 50,000 ppm (standard range: 50,000 ± 10,000 ppm) and a [free chlorine concentration (as Cl = 35.45)] of approximately 1,500 mg / L (standard value: 1,250 mg / L or more). However, if the actual measured value differs significantly from the assumed value, the set value will be recalculated to match the actual measured value.

[0268] Indirect blending (2): A blending method for hypochlorous acid water preparations that is prepared by mixing hypochlorous acid (chlorine peroxide radicals (ClOO·)) with GB chlorine dioxide water and then passing it through hypochlorous acid water.

[0269] Formula for calculating the blending ratio [Indirect blending (2): chlorous acid = chlorine peroxide radical (ClOO·) used}]

[0270] - Mixing ratio of chlorous acid = chlorine peroxide radical (ClOO·): dd = [free chlorine concentration setting: 8 (mg / L)] (*9) * 102 (%) / [free chlorine concentration of chlorous acid = chlorine peroxide radical (ClOO·) (mg / L)]

[0271] ・Chlorine dioxide water blending ratio: ee = ([Content setting: 275 (ppm)] * 102 (%)] - [Chlorous acid = chlorine peroxide radical (ClOO.) content (ppm)] * d (%)) / [Chlorine dioxide water content (ppm)]

[0272] ・Ion-exchange water blending ratio: ff = 102 (%) - [d (%) + e (%) + Z (%)]

[0273] *9) From the results of preliminary trial production, it has been found that when a prototype (chlorous acid water formulation) is made using chlorous acid = chlorine peroxide radical (ClOO·) prepared in indirect blending (1), the resulting [free chlorine concentration (assuming Cl = 35.45)] does not decrease significantly from the set value, just as when a prototype (chlorous acid water formulation) is made using chlorous acid water. Therefore, the set value for [free chlorine concentration (assuming Cl = 35.45)] here is set to a value that is expected to be equivalent to the [free chlorine concentration (assuming Cl = 35.45)] of a prototype (chlorous acid water formulation) made by directly adding chlorous acid = chlorine peroxide radical (ClOO·), just as when a prototype (chlorous acid water formulation) is made using chlorous acid water.

[0274] (4) To confirm the quality of each prototype, the following items were measured. First, it was confirmed whether the actual measured values ​​of each prototype met the standard values ​​for low-concentration hypochlorous acid water formulations. In addition, the actual measured values ​​at the time of production of each prototype were compared to confirm whether differences in raw materials, formulation and method (direct blending vs. indirect blending) would result in differences in the quality of the finished products.

[0275] [Manufacturing specifications]

[0276] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *6) Value obtained by the standard hydrometer method *10) Results obtained by visual inspection *11) Results obtained by spectrophotometric method

[0277] (5) After filling each prototype into a container, it was stored at 40°C for 180 days, and the following items were measured on each measurement date (D+0, D+5, D+10, D+20, D+30, D+60, D+90, D+120, D+150, D+180). By comparing the shelf life of each prototype, it was confirmed whether differences in raw materials, formulation and method (direct formulation vs. indirect formulation) would result in differences in the change over time (whether the free chlorine concentration (assuming Cl = 35.45) can be maintained for a longer period of time).

[0278] To match the void space inside the container, the weight to be filled into the container is set at 100±1g.

[0279]

[0280] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *10) Results obtained by visual inspection *11) Results obtained by spectrophotometric method

[0281] 5. Results (1) Measurement results of chlorous acid = chlorine peroxide radical (ClOO.) *1) Value obtained by the glass electrode method *2) Value obtained by the iodometric reduction titration method (unit: ppm) *3) Value obtained by the colorimetric method (DPD method) (unit: mg / L)

[0282] (3)

[0283] (4) Quality of the finished product *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *6) Value obtained by the standard hydrometer method *10) Results obtained by visual inspection *11) Results obtained by spectrophotometric method

[0284] (5) Storage test [Chlorous acid water preparation prepared using chlorous acid water] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *6) Value obtained by the standard hydrometer method *10) Results obtained by visual inspection *11) Results obtained by spectrophotometry *13) Values ​​shown as percentages, with the value of D+0 being 100%

[0285] [Chlorous acid = chlorine peroxide radical (ClOO.) directly added to the prototype chlorous acid water preparation] (Direct blending) *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *6) Value obtained by the standard hydrometer method *10) Results obtained by visual inspection *11) Results obtained by spectrophotometry *13) Values ​​shown as percentages, with the value of D+0 being 100%

[0286] [Chlorous acid = a hypochlorous acid solution prepared by mixing chlorine peroxide radical (ClOO·) with GB chlorine dioxide water to create hypochlorous acid water, which is then added as a prototype] (indirect blending) *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *6) Value obtained by the standard hydrometer method *10) Results obtained by visual inspection *11) Results obtained by spectrophotometry *13) Values ​​shown as percentages, with the value of D+0 being 100%

[0287] 6. Discussion Final report <Quality at time of production> The finished products of each prototype were produced based on a formulation using hypochlorous acid water as a raw material and a formulation using hypochlorous acid = chlorine peroxide radical (ClOO.) as a raw material (direct blending and indirect blending), and the free chlorine concentration (as Cl = 35.45) and content (as hypochlorous acid (HClO2 = 68.46)), as well as pH, properties, specific gravity and UV spectrum were measured and the actual measured values ​​were confirmed. The free chlorine concentration (as Cl = 35.45) and content (as hypochlorous acid (HClO2 = 68.46)), pH, properties and specific gravity of all the prototypes were within the ranges that had been set in advance as standard values ​​(proposed).

[0288] Regarding the UV spectrum, there were concerns that the bimodal peak might not be observed because the hypochlorous acid water formulation in question had a very low concentration of 275±25 ppm (as hypochlorous acid (HClO2=68.46)) and 5 mg / L (as free chlorine concentration (Cl=35.45)). However, bimodal peaks were confirmed in all prototypes, and it was found that even with a low concentration hypochlorous acid water formulation (200 ppm), the bimodal peaks characteristic of hypochlorous acid water formulations were observed at the time of production.

[0289] From the above, it was found that during production, differences in raw materials and manufacturing recipes (direct blending vs. indirect blending) do not result in significant differences (are not affected) in the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)).

[0290] <Storage test> It was confirmed that the measured values ​​of the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] of the finished products of each prototype under different conditions met the range of pre-set specifications. Based on this, each prototype will be stored at 40°C, and the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content as chlorous acid (HClO2 = 68.46)] will be confirmed {[free chlorine concentration (as Cl = 35.45)] will be confirmed, and whether these concentrations can be maintained at 5 mg / L or longer} will be confirmed, along with the contents of [1] to [3].

[0291] [1] Investigation into the reproducibility of hypochlorous acid water After 180 days of storage at 40°C, the prototype (Cont1) of a low-concentration hypochlorous acid water formulation (200 ppm product) using hypochlorous acid water as a raw material had a free chlorine concentration (based on Cl = 35.45) below 5 mg / L after 150 days of storage at 40°C, and the free chlorine concentration (based on Cl = 35.45) can be maintained at 5 mg / L or above for up to 120 days of storage at 40°C.

[0292] However, in this regard, even in a prototype of a low-concentration chlorous acid water formulation (200 ppm product) using chlorous acid water as a raw material and a 0.1 mol / L phosphate buffer solution at pH 4.5, the [free chlorine concentration (Cl = 35.45)] was maintained at 5 mg / L or more up to 120 days after storage at 40°C, but fell below 5 mg / L after 150 days. This shows that the test is sufficiently reproducible.

[0293] Furthermore, with regard to the content (as chlorous acid (HClO2 = 68.46)) of the prototype Cont1 in this test after 180 days of storage at 40°C, the residual content (as chlorous acid (HClO2 = 68.46)) was approximately the same as that of a prototype low-concentration chlorous acid water formulation (200 ppm product) made using chlorous acid water as a raw material and 0.1 mol / L phosphate buffer solution at pH 4.5, and the change over time also showed a similar trend to the results of the test conducted up to 180 days after storage at 40°C.

[0294] Based on the above, a prototype (Cont1) of a low-concentration chlorous acid water formulation (200 ppm) using chlorous acid water as a raw material was stored at 40°C for 180 days. As a result, it was confirmed that the free chlorine concentration (based on Cl = 35.45) can be maintained at 5 mg / L or above for 120 days at 40°C. Furthermore, the changes over time in the free chlorine concentration (based on Cl = 35.45) and content (based on chlorous acid (HClO2 = 68.46)) showed similar trends to those seen in the storage test of chlorous acid water conducted over a 180-day period at 40°C. Based on this, it is believed that the results of the test conducted are sufficiently reproducible.

[0295] Furthermore, in a previous test conducted on a low-concentration hypochlorous acid water formulation (200 ppm product) in 0.1 mol / L phosphate buffer, it was reported that a prototype using a pH of 4.5 was able to maintain a free chlorine concentration (based on Cl = 35.45) of 5 mg / L or higher for a longer period than a prototype using a pH of 5.0. Therefore, this test was also conducted using a 0.1 mol / L phosphate buffer solution at pH 4.5. As a result, the results of the test conducted were reproducible, and it is believed that there is no problem with the fact that a 0.1 mol / L phosphate buffer solution at pH 4.5 can maintain a free chlorine concentration (based on Cl = 35.45) for a longer period than a pH of 5.0.

[0296] Based on this, we concluded that it would be better to use a 0.1 mol / L phosphate buffer solution with a pH of 4.5 as a buffer for low-concentration hypochlorous acid preparations (200 ppm product).

[0297] [2] Investigation into the differences in raw materials used in hypochlorous acid water preparations (200 ppm product) After storage at 40°C for 180 days, the free chlorine concentration (as Cl = 35.45) and content (as hypochlorous acid (HClO2 = 68.46)) of the prototype (Cont. 1) using hypochlorous acid water as a raw material and the prototypes (Test 1 to Test 2) using hypochlorous acid = chlorine peroxide radical (ClOO·) as a raw material showed similar changes in all prototypes up to 180 days after storage at 40°C, and no particular differences were observed in the changes over time in the free chlorine concentration (as Cl = 35.45) and content (as hypochlorous acid (HClO2 = 68.46)).

[0298] From this, it was found that when a prototype (Cont1) using hypochlorous acid water as a raw material for a low-concentration hypochlorous acid water formulation (200 ppm product) and a prototype (Test1-Test2) using hypochlorous acid = chlorine peroxide radical (ClOO·) as a raw material were stored at 40°C for 180 days, there was no significant difference in the time it took for the [free chlorine concentration (based on Cl = 35.45)] to fall below 5 mg / L, or in the actual measured value of the [content (based on hypochlorous acid (HClO2 = 68.46))] or the change in its residual rate over time (all were the same).

[0299] [3] Investigation into the manufacturing formula for hypochlorous acid water preparations (200 ppm product) After storage at 40°C for 180 days, the free chlorine concentration (as Cl = 35.45) and the content (as hypochlorous acid (HClO2 = 68.46)) of the prototype (Test 1) made by "direct blending" and the prototype (Test 2) made by "indirect blending" showed similar trends up to 180 days after storage at 40°C, and no particular difference was observed in the changes over time in the free chlorine concentration (as Cl = 35.45) and the content (as hypochlorous acid (HClO2 = 68.46)).

[0300] From this, it was found that when a prototype (Test 1) made by "direct blending" and a prototype (Test 2) made by "indirect blending" of a low-concentration hypochlorous acid water formulation (200 ppm product) were stored at 40°C for 180 days, there were no significant differences in the actual measured values ​​of [free chlorine concentration (as Cl = 35.45)] and [content (as hypochlorous acid (HClO2 = 68.46))] or changes in its residual rate over time (all were the same) due to differences in manufacturing formula.

[0301] <Summary of Results> Based on the above results, in order to confirm the difference in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] due to differences in raw materials and manufacturing recipes (direct vs. indirect), prototypes were produced under different conditions and stored at 40°C for 180 days. The results are summarized in the table below. [What was learned from the results for [1] to [3] after 180 days of storage at 40°C]

[0302] The above table summarizes what was learned from the results of creating prototypes with different raw materials and manufacturing formulas (direct and indirect blending) and checking the differences in changes over time for 180 days at 40°C.Regarding the UV spectrum, when the actual measured values ​​of the UV spectrum of each prototype were checked up to 180 days after storage at 40°C, it was found that in all prototypes, the double nodule peaks were observed for 180 days after storage at 40°C, and it was found that even in low-concentration hypochlorous acid water preparations (200 ppm product), the double nodule peaks that are characteristic of hypochlorous acid water preparations were observed for 180 days after storage at 40°C.

[0303] Furthermore, as noted in [2], for the prototype using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material, the changes over time in its [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] show similar trends to those for the prototype using chlorous acid water as the raw material, and no difference was observed in the period during which the [free chlorine concentration (as Cl = 35.45)] could be maintained at 5 mg / L or higher. From this, it was found that there was no difference in the changes over time in [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] due to the difference in raw materials.

[0304] However, after 20 days of storage at 40°C, when the [free chlorine concentration (as Cl = 35.45)] reaches its maximum, there is no difference in the residual rate of [content (as chlorous acid (HClO2 = 68.46))] between the prototypes using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material and the prototypes using chlorous acid water as the raw material, but it was found that the [free chlorine concentration (as Cl = 35.45)] is slightly higher in the prototypes using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material (Test 1, Test 2) than in the prototype using chlorous acid water as the raw material (Cont 1). Therefore, based on this, it is believed that the cycle reaction in which [free chlorine concentration (as Cl = 35.45)] is produced from [content (as chlorous acid (HClO2 = 68.46))] functions more efficiently in the prototypes (Test 1, Test 2) that use chlorous acid = chlorine peroxide radical (ClOO.) as the raw material than in the prototype that uses chlorous acid water as the raw material.

[0305] Furthermore, both the prototype using chlorous acid = chlorine peroxide radical (ClOO·) as a raw material and the prototype using chlorous acid water as a raw material were able to maintain a free chlorine concentration (assuming Cl = 35.45) of 5 mg / L or higher for a certain period of time, and there was also a tendency for this to gradually decrease with the content. This shows that the chlorous acid water cycle reaction is functioning properly whether chlorous acid water or chlorous acid = chlorine peroxide radical (ClOO·) is used as a raw material, and furthermore, the double nodule peaks that are characteristic of chlorous acid water formulations were confirmed over a period of 180 days at 40°C, meaning that this prototype inherited the characteristics of chlorous acid water.

[0306] However, as stated in [2], as a result, no difference was observed in the period during which the [free chlorine concentration (based on Cl = 35.45)] could be maintained at 5 mg / L or more between the prototype using hypochlorous acid water as a raw material and the prototype using hypochlorous acid = chlorine peroxide radical (ClOO·) as a raw material. As mentioned above, it is believed that the cycle reaction is functioning, but in the case of a low-concentration hypochlorous acid water formulation (200 ppm product), the original [content (based on hypochlorous acid (HClO2 = 68.46))] is only about 275 ppm, so even if free chlorine is efficiently generated using hypochlorous acid = chlorine peroxide radical (ClOO·), the formulation conditions make it difficult to maintain this efficiently generated free chlorine, and it is believed that the difference would not be apparent over a period of 180 days at 40°C.

[0307] Based on the above, when used as a raw material for low-concentration hypochlorous acid water formulations (200 ppm product), after 180 days of storage at 40°C, no significant differences were observed in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as hypochlorous acid (HClO2 = 68.46))] due to the difference in raw materials. However, it was found that the prototypes (Test 1, Test 2) using hypochlorous acid = chlorine peroxide radical (ClOO·) as a raw material were able to more efficiently produce [free chlorine concentration (as Cl = 35.45)] from [content (as hypochlorous acid (HClO2 = 68.46))], and it was determined that it is better to use hypochlorous acid = chlorine peroxide radical (ClOO·) as a raw material for low-concentration hypochlorous acid water formulations (200 ppm product).

[0308] [Changes in free chlorine concentration (assuming Cl = 35.45) for each prototype over time from D+0 to D+20] *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *13) Value shown as a percentage, with the value of D+0 being 100%.

[0309] [Changes in the content (as chlorous acid (HClO2 = 68.46)) of each prototype over time from D+0 to D+20] *2) Value obtained by iodometric titration (unit: ppm) *13) Value shown as a percentage, with the value of D+0 being 100%.

[0310] These results confirm that for low-concentration chlorous acid water formulations (200 ppm), using a 0.1 mol / L phosphate buffer solution with a pH set at 4.5 can maintain a free chlorine concentration (as Cl = 35.45) of 5 mg / L or higher for up to 120 days at 40°C. It also indicates that using chlorous acid (chlorine peroxide radical (Cl00·)) as a raw material efficiently produces a free chlorine concentration (as Cl = 35.45) from the content (as chlorous acid (HClO2 = 68.46)). Figure 10 shows a graph of the change in the free chlorine concentration (as Cl = 35.45) over time for each prototype. Figure 11 shows a graph of the change in the content (as chlorous acid (HClO2 = 68.46)) over time for each prototype.

[0311] For low-concentration hypochlorous acid water formulations (200 ppm (0.02 wt%)), by using a 0.1 mol / L phosphate buffer solution set to pH 4.5, it was possible to maintain a free chlorine concentration (assuming Cl = 35.45) of 5 mg / L or higher for 120 days (equivalent to more than two years at room temperature) even under the harsh conditions of 40°C, and it was found that this formulation is the optimal condition for low-concentration hypochlorous acid water formulations.

[0312] (Example 6: Storage test of high-concentration hypochlorous acid water formulation (8000 ppm (0.8 wt %) product) A prototype (hypochlorous acid water formulation) made using hypochlorous acid = chlorine peroxide radical (ClOO.) as a raw material and a prototype (hypochlorous acid water formulation) made using hypochlorous acid water as a raw material were compared with prototypes (hypochlorous acid water formulations) made using different buffer solutions and different raw materials, respectively, to confirm the reproducibility of the results of the storage test, and to confirm whether differences in the raw materials, formulations, and methods would result in differences in the finished state of each prototype and subsequent changes over time {whether the free chlorine concentration (assuming Cl = 35.45)] could be maintained for a longer period?}

[0313] <Contents of the study> [1] Confirmation of reproducibility Using hypochlorous acid water as the raw material, prototypes were made using phosphate buffer solution (current) and citrate buffer solution, and by checking the differences in the finished state due to the difference in buffer solution and the subsequent changes over time, it was confirmed whether trends similar to those in the storage tests previously conducted could be observed.

[0314] [2] Raw materials used in hypochlorous acid water preparations (8,000 ppm product) By comparing a prototype (hypochlorous acid water preparation) made using hypochlorous acid = chlorine peroxide radical (ClOO.) as a raw material with a prototype (hypochlorous acid water preparation) made using hypochlorous acid water, we confirmed whether there were any differences in the finished state due to the difference in raw materials and whether any differences would appear in subsequent changes over time.

[0315] [3] Formulation and method of hypochlorous acid water preparation (8,000 ppm product) When hypochlorous acid = chlorine peroxide radical (ClOO·) is used as a raw material, it was confirmed whether there would be any difference in the finished state due to the difference in formulation and method, or whether there would be any difference in subsequent changes over time, when hypochlorous acid = chlorine peroxide radical (ClOO·) was directly added (direct formulation), or when it was mixed with GB chlorine dioxide water to make hypochlorous acid water and then added after passing through this (indirect formulation).

[0316] [4] Setting pH of citrate buffer solution It is already known that when chlorous acid = chlorine peroxide radical (ClOO·) is used as a raw material, the finished product has a low pH, and it is also known that a citrate buffer solution of pH 6.0 is required to match the pH of the 8,000 ppm product. Therefore, when chlorous acid = chlorine peroxide radical (ClOO·) is used as a raw material, prototypes were made using citrate buffer solutions of pH 5.0 and pH 6.0, and it was confirmed whether the difference in the pH of the citrate buffer solution would result in differences in the finished product and whether any differences would appear in the subsequent changes over time.

[0317] Therefore, in order to confirm the above contents [1] to [4], we prepared prototypes for each of the following test areas and compared each prototype to confirm the differences in the finished state and the subsequent changes over time.

[0318] 2. Purpose Using various buffer solutions in each pH range, prototypes will be made to confirm the above [1] to [4] using chlorous acid = chlorine peroxide radical (ClOO·) or chlorous acid water as the raw material, and after confirming the finished state of each prototype, changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] will be confirmed in a storage test, and the results will be compared between each prototype to confirm the reproducibility of the storage test results, as well as to confirm whether any differences emerge in the finished state due to differences in buffer solutions, raw materials, formulations and methods (direct and indirect blending), and differences in the pH of the buffer solutions, and in the subsequent changes over time {whether the [free chlorine concentration (as Cl = 35.45)] can be maintained for a longer period}. 3. Samples, raw materials *Raw materials

[0319] *Equipment and equipment: electronic balance, pH meter, measuring cylinder, stirrer, stirring bar, beaker, Erlenmeyer flask with stopper, standard hydrometer, spectrophotometer, quartz cell

[0320] *Reagents: Potassium iodate, sodium thiosulfate pentahydrate, potassium iodide, sulfuric acid, starch (soluble), sodium azide, sodium carbonate, hydrochloric acid, potassium hydrogen phthalate, potassium dihydrogen phosphate, disodium hydrogen phosphate, sodium tetraborate decahydrate, DPD reagent 4. Method (1) Chlorous acid = chlorine peroxide radical (ClOO·) was prepared. Note that when using chlorous acid = chlorine peroxide radical (ClOO·) for testing, the following specification range is used as a guide, so the pH, [content (as chlorous acid (HClO2 = 68.46)], and [free chlorine concentration (as Cl = 35.45)] of the prepared chlorous acid = chlorine peroxide radical (ClOO·) were measured to confirm whether they fell within the following specification range. *1) Value obtained by the glass electrode method *2) Value obtained by the iodometric reduction titration method (unit: ppm) *3) Value obtained by the colorimetric method (DPD method) (unit: mg / L)

[0321] (2) Prepare various buffer solutions according to the following formulations: ◆ 0.1 mol / L phosphate buffer solution (pH 5.0) (current formulation) (TR-S1640D)

[0322] ◆ Formulated with citrate buffer (pH 5.0) (※5)

[0323] ◆ Formulated with citrate buffer (pH 6.0) (※5) *5) The citrate buffer formulation is determined by the ratio of the concentrations of citric acid and citrate salts when solutions of citric acid monohydrate (9179.0_A0064: "Purified citric acid (crystals)") and trisodium citrate dihydrate (9131.0_A0950: "Trisodium citrate (crystals)") at each concentration (0.075% or 0.1%) are combined and adjusted to the target pH (pH 5.0 or pH 6.0).

[0324] (3) Using the various buffer solutions prepared in (2), a prototype (chlorous acid water preparation) using chlorous acid water as a raw material and a prototype (chlorous acid water preparation) using chlorous acid = chlorine peroxide radical (ClOO ) as a raw material are prepared according to the following formulations.

[0325] Furthermore, in this test, the differences in the raw materials used between prototypes using hypochlorous acid water and prototypes using hypochlorous acid = chlorine peroxide radical (ClOO·) are to be compared, as well as the differences in the formulation and method of prototypes in which hypochlorous acid = chlorine peroxide radical (ClOO·) is directly and indirectly blended. Therefore, in order to keep the final concentrations of citric acid and citrate consistent, the blending ratios (%) of the various buffer solutions are matched to those of the prototypes that use hypochlorous acid water as a raw material (hypochlorous acid water formulation).

[0326] [Hydrochlorous acid water preparation containing hypochlorous acid water] Formulation of hypochlorous acid water preparation containing hypochlorous acid water

[0327] Formula for calculating the blending ratio [hypochlorous acid water] Blending ratio of hypochlorous acid water: XX = [free chlorine concentration setting: 250 (mg / L)] (※6) * 102%) / [free chlorine concentration of hypochlorous acid water (mg / L)]

[0328] ・Chlorine dioxide water blending ratio: YY = ([Content setting value: 8800 (ppm)] * 102 (%)] - [chlorous acid water content (ppm)] * X (%)) / [chlorine dioxide water content (ppm)]

[0329] ・Blending ratio of various buffer solutions: ZZ = 102 (%) - [X (%) + Y (%)]

[0330] *6) The set value for the [free chlorine concentration (assuming Cl = 35.45)] for formulations using hypochlorous acid water has been set in advance to a value that is expected to be equivalent to the [free chlorine concentration (assuming Cl = 35.45)] of the finished prototype (hypochlorous acid water formulation) using hypochlorous acid = chlorine peroxide radical (ClOO·).

[0331] [Chlorous acid = chlorine peroxide radical (ClOO·) directly charged as is in a hypochlorous acid water preparation] (Direct blending) ◆ Formulation of hypochlorous acid = chlorine peroxide radical (ClOO·) directly charged as is in a hypochlorous acid water preparation

[0332]

[0333] *7) The blending ratio (%) of various buffer solutions will be the same as that of the prototype (hypochlorous acid water preparation) that uses hypochlorous acid water as a raw material, and the remainder will be blended with ion-exchanged water.

[0334] ◆ Calculation formula for determining the blending ratio (direct blending) [Chlorous acid = chlorine peroxide radical (ClOO·)] Blending ratio of chlorous acid = chlorine peroxide radical (ClOO·): aa = [Set value of free chlorine concentration: 400 (mg / L)] (※8) * 102 (%) / [Free chlorine concentration of chlorous acid = chlorine peroxide radical (ClOO·) (mg / L)]

[0335] ・Chlorine dioxide water blending ratio: bb = ([Set content: 8800 (ppm)] * 102 (%) - [Chlorous acid = chlorine peroxide radical (ClOO.) content (ppm)] * a (%)) / [Chlorine dioxide water content (ppm)]

[0336] ・Ion-exchange water blending ratio: cc = 102 (%) - [a (%) + b (%) + Z (%)]

[0337] *8) When chlorous acid (chlorine peroxide radicals, ClOO) is directly added to make a chlorous acid water formulation (8,000 ppm), it has already been found that the final [free chlorine concentration (assuming Cl = 35.45)] is just over 60% of the set value. It has also been confirmed that by setting the [free chlorine concentration (assuming Cl = 35.45)] value to 400 mg / L, the final [free chlorine concentration (assuming Cl = 35.45)] falls within the range of 200 mg / L or more, which is the standard value for chlorous acid water (8,000 ppm). Therefore, the set value for [free chlorine concentration (assuming Cl = 35.45)] is set to 400 mg / L.

[0338] [Chlorous acid = chlorine peroxide radical (ClOO·) and GB chlorine dioxide water mixed to make hypochlorous acid water, then mixed with hypochlorous acid water (indirect blending) Indirect blending (1): [Chlorous acid = chlorine peroxide radical (ClOO·) and GB chlorine dioxide water mixed to make hypochlorous acid water]

[0339]

[0340] ◆Calculation formula for finding the blending ratio [Indirect blending (1): chlorous acid = chlorine peroxide radical (ClOO·)] Blending ratio of chlorous acid = chlorine peroxide radical (ClOO·): γ γ = [Set value of free chlorine concentration: 2500 (mg / L)] (※9) * 102 (%) / [Free chlorine concentration of chlorous acid = chlorine peroxide radical (ClOO·) (mg / L)]

[0341] ・Blending ratio of chlorine dioxide water: δ δ = ([Set content: 50,000 (ppm)] (※9) * 102 (%) - [Chlorous acid = chlorine peroxide radical (ClOO.) content (ppm)] * γ) / [chlorine dioxide water content (ppm)]

[0342] - Ion-exchange water blending ratio: ε ε = 102 (%) - [γ (%) + δ (%)]

[0343] *9) From the results of preliminary prototype testing, it has been found that even when hypochlorous acid water is made by mixing hypochlorous acid (chlorine peroxide radicals) and GB chlorine dioxide water, the resulting [free chlorine concentration (assuming Cl = 35.45)] will be just over 60% of the set value. Therefore, the set value for [free chlorine concentration (assuming Cl = 35.45)] is calculated and set to a value that is expected to be approximately the same as the [free chlorine concentration (assuming Cl = 35.45)] of hypochlorous acid water.

[0344] Furthermore, the set value for [content (as chlorous acid (HClO2 = 68.46))] is also set to a value that is approximately the same as the actual measured value of [content (as chlorous acid (HClO2 = 68.46)]] of hypochlorous acid water, in order to match it with the [content (as chlorous acid (HClO2 = 68.46)] of hypochlorous acid water.

[0345] However, here, the set values ​​are calculated assuming that the hypochlorous acid water has a [content (as hypochlorous acid (HClO2 = 68.46))] of approximately 50,000 ppm (standard range: 0,000 ± 10,000 ppm) and a [free chlorine concentration (as Cl = 35.45)] of approximately 500 mg / L (standard value: 250 mg / L or more). However, if the actual measured value differs significantly from the assumed value, the set value is recalculated to match the actual measured value.

[0346] Indirect blending (2): A hypochlorous acid solution formulation prototype prepared by mixing liquid [hypochlorous acid] (chlorine peroxide radical (ClOO·)) with GB chlorine dioxide water to create hypochlorous acid water.

[0347] *7) The blending ratio (%) of various buffer solutions will be the same as that of the prototype (hypochlorous acid water preparation) that uses hypochlorous acid water as a raw material, and the remainder will be blended with ion-exchanged water.

[0348] ◆ Formula for calculating the blending ratio [Indirect blending (2): chlorous acid = chlorine peroxide radical (ClOO·)]

[0349] - Mixing ratio of chlorous acid = chlorine peroxide radical (ClOO·): dd = [free chlorine concentration setting: 250 (mg / L)] (*10) * 102 (%) / [free chlorine concentration of chlorous acid = chlorine peroxide radical (ClOO·) (mg / L)]

[0350] ・Chlorine dioxide water blending ratio: ee = ([Content setting: 8800 (ppm)] * 102 (%)] - [Chlorous acid = chlorine peroxide radical (ClOO.) content (ppm)] * d (%)) / [Chlorine dioxide water content (ppm)]

[0351] ・Ion-exchange water blending ratio: ff = 102 (%) - [d (%) + e (%) + Z (%)]

[0352] *10) From the results of preliminary trial production, it has been found that when a prototype (chlorous acid water formulation) is made using chlorous acid = chlorine peroxide radical (ClOO·) prepared in indirect blending (1), the resulting [free chlorine concentration (assuming Cl = 35.45)] does not decrease significantly from the set value, just as when a prototype (chlorous acid water formulation) is made using chlorous acid water. Therefore, the set value for [free chlorine concentration (assuming Cl = 35.45)] here is set to a value that is expected to be equivalent to the [free chlorine concentration (assuming Cl = 35.45)] of a prototype (chlorous acid water formulation) made by directly adding chlorous acid = chlorine peroxide radical (ClOO·), just as when a prototype (chlorous acid water formulation) is made using chlorous acid water.

[0353] (4) In order to confirm the quality of each prototype, the following items were measured, and first, it was confirmed whether the actual measured values ​​of each prototype met the standard values ​​(draft) of the hypochlorous acid water formulation (8,000 ppm product).

[0354] In addition, the actual measured values ​​of the finished products of each prototype were compared to confirm whether there were any differences in the finished state due to differences in buffer solutions, raw materials, formulation and method (direct blending and indirect blending), and pH of the buffer solutions.

[0355] However, when chlorous acid = chlorine peroxide radical (Cl00·) is used as a raw material, it has already been confirmed that when a prototype (chlorous acid water formulation) is made using a 0.075% or 0.1% citrate buffer solution with a pH of 5.0, the finished product has a low pH. Based on this, it is predicted that the pH of a prototype made using chlorous acid = chlorine peroxide radical (Cl00·) as a raw material and a citrate buffer solution with a pH of 5.0 will not fall within the proposed standard value range. However, the actual measured value will be recorded for reference.

[0356]

[0357] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *12) Value (numerical value) obtained by the standard hydrometer method *13) Results obtained by spectrophotometry

[0358] (5) After filling each prototype into a container, it was stored at 40°C for 180 days, and the following items were measured on each measurement date (D+0, D+5, D+10, D+20, D+30, D+60, D+90, D+120, D+150, D+180). By comparing the shelf life of each prototype, it was confirmed whether differences in buffer solution, raw materials, formulation and method (direct blending vs. indirect blending), and buffer solution pH would result in differences in changes over time (whether the free chlorine concentration (assuming Cl = 35.45) can be maintained for a longer period).

[0359] To match the void space within the container, the weight to be filled into the container is set at 100±1g.

[0360] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometric method

[0361] 6. Results (1) Measurement results of chlorous acid = chlorine peroxide radical (ClOO.) *1) Value obtained by the glass electrode method *2) Value obtained by the iodometric reduction titration method (unit: ppm) *3) Value obtained by the colorimetric method (DPD method) (unit: mg / L)

[0362] (3) Measurement results of hypochlorous acid water *1) Value obtained by the glass electrode method *2) Value obtained by the iodometric reduction titration method (unit: ppm) *3) Value obtained by the colorimetric method (DPD method) (unit: mg / L)

[0363] ◆GB chlorine dioxide water measurement results *2) Value obtained by iodometric titration (unit: ppm)

[0364] Indirect blending (1): Measurement results for hypochlorous acid water made by mixing hypochlorous acid (chlorine peroxide radicals (ClOO·)) and GB chlorine dioxide water. *1) Value obtained by the glass electrode method *2) Value obtained by the iodometric reduction titration method (unit: ppm) *3) Value obtained by the colorimetric method (DPD method) (unit: mg / L)

[0365] (4) Quality of the finished product Hypochlorous acid water preparation containing hypochlorous acid water

[0366] ◆Chlorous acid = Chlorine peroxide radical (ClOO·) is directly added as a prototype of a hypochlorous acid water preparation (direct blending)

[0367] ◆Chlorous acid = A hypochlorous acid solution prepared by mixing chlorine peroxide radical (ClOO·) with GB chlorine dioxide water and then adding it to the test (indirect blending).

[0368] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *12) Value (numerical value) obtained by the standard hydrometer method *13) Results obtained by spectrophotometry

[0369] (5) Storage test ◆ Hypochlorous acid water preparation containing hypochlorous acid water Blank (1) (current)

[0370] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0371] Cont (1)

[0372] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100% Cont (2) *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0373] ◆Chlorous acid = Chlorine peroxide radical (ClOO·) was directly added as a prototype of hypochlorous acid water preparation (direct blending) Test (1)

[0374] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100% Test (2)

[0375]

[0376] Test (3)

[0377] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0378] Test (4)

[0379] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0380] ◆Chlorous acid = A hypochlorous acid solution prepared by mixing chlorine peroxide radical (ClOO·) with GB chlorine dioxide water and then adding it to the test (indirect blending).

[0381] Test (5)

[0382] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0383] Test (6)

[0384] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0385] Test (7)

[0386] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0387] Test (8)

[0388] *1) Value obtained by the glass electrode method *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetry (DPD method) (unit: mg / L) *11) Results obtained by visual inspection *13) Results obtained by spectrophotometry *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0389] Observations 〇 Interim report (up to D+30) <Quality at the time of production> First, the [free chlorine concentration (as Cl = 35.45)] and [content as chlorous acid (HClO2 = 68.46)] of the finished product of each prototype that was produced were measured and confirmed, as well as the pH, properties, specific gravity, and UV spectrum. All of the actual measured values ​​for the [free chlorine concentration (as Cl = 35.45)] and [content as chlorous acid (HClO2 = 68.46)], properties, and UV spectrum were found to be within the ranges set in advance as standard values.

[0390] This shows that during production, differences in buffer solution, raw materials, formulation and method (direct blending vs. indirect blending), and buffer solution pH do not result in any significant difference (are not affected) in the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)).

[0391] Furthermore, among the prototypes that used chlorous acid = chlorine peroxide radical (ClOO.) as a raw material, the prototypes that were "directly blended" and used a citrate buffer solution of pH 5.0 (Test (1) and Test (2)) and the prototypes that were "indirectly blended" and used a citrate buffer solution of pH 6.0 (Test (7) and Test (8)) had pH values ​​outside the range of the specification at the time of production, but it is known that the pH of the prototypes that used citrate buffer solutions was outside the range of the specification at the time of production and during the storage period.

[0392] Therefore, although it will be necessary to confirm whether differences in the [free chlorine concentration (as Cl = 35.45)] and [chlorous acid content (HClO2 = 68.46)] change over time due to differences in pH, at the time of production, we believe that there are no particular differences (not apparent) in the [free chlorine concentration (as Cl = 35.45)] and [chlorous acid content (HClO2 = 68.46)] due to differences in pH, and if it is found that the [free chlorine concentration (as Cl = 35.45)] of the prototype using citrate buffer can be maintained longer than the current product, we will change the specification value at the time of production.

[0393] <Changes in quality over time (up to D+180)> It was confirmed that the quality of the finished products of each prototype ([free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46)]) satisfies the range set in advance as the standard value. Next, each prototype will be stored at 40°C to check whether the [free chlorine concentration (as Cl = 35.45)] can be maintained for a longer period, and the contents of [1] to [5] will be confirmed.

[0394] [1] Confirmation of reproducibility <Up to D+30> It was found that the prototypes using pH 5.0 citrate buffer (Cont (1), Cont (2)) had a higher [free chlorine concentration (as Cl = 35.45)] than the prototype using the current 0.1 mol / L phosphate buffer (Blank (1)), and were also able to maintain a high [content (as chlorous acid (HClO2 = 68.46))], confirming that the tests conducted were reproducible.

[0395] Furthermore, with regard to the concentration of the pH 5.0 citrate buffer, the results to date (stored at 40°C, D+30) show that the prototype using 0.1% citrate buffer (Cont (2)) maintains a higher [free chlorine concentration (as Cl = 35.45)] than the prototype using 0.075% citrate buffer (Cont (1)). Therefore, assuming that it is better to be able to maintain the [free chlorine concentration (as Cl = 35.45)] for a longer period than the current product, it is judged that 0.1% citrate buffer is better.

[0396] Results as of D+30<D+90まで> The results up to D+90 when stored at 40°C continued to show a similar trend to the results up to D+30. Furthermore, it was found that the prototype (Blank (1)) using the current 0.1 mol / L phosphate buffer solution had a free chlorine concentration (based on Cl = 35.45) below 200 mg / L at D+60 when stored at 40°C. It has been confirmed that the free chlorine concentration (based on Cl = 35.45) of the chlorous acid water formulation using 0.1 mol / L phosphate buffer solution fell below 200 mg / L at D+60 when stored at 40°C. Therefore, the fact that the free chlorine concentration (based on Cl = 35.45) of the chlorous acid water formulation using 0.1 mol / L phosphate buffer solution fell below 200 mg / L at D+60 when stored at 40°C is not a problem in itself; rather, it deserves to be evaluated as demonstrating good reproducibility.

[0397] Results as of D+90 <Up to D+120> In the results up to D+120 after storage at 40°C, the prototypes (Cont (1), Cont (2)) using a pH 5.0 citrate buffer solution maintained a free chlorine concentration (assuming Cl = 35.45) of 200 mg / L or more, and the trend was similar to the results up to D+90, demonstrating that the results of the tests conducted were reproducible.

[0398] Results as of D+120 <Up to D+150> In the results up to D+150 when stored at 40°C, the free chlorine concentration (assuming Cl=35.45) of Cont (1), a prototype using 0.075% citrate buffer solution at pH 5.0, reached 200 mg / L, and it is thought that by D+180 when stored at 40°C, the free chlorine concentration (assuming Cl=35.45) may fall below 200 mg / L.

[0399] However, the prototype using 0.075% citrate buffer solution at pH 5.0 had a free chlorine concentration (assuming Cl = 35.45) of 205 mg / L at D+150 when stored at 40°C, and maintained a value close to 200 mg / L. Furthermore, when the residual rate of the free chlorine concentration (assuming Cl = 35.45) was checked, it was found that the residual rate of Cont (1), the prototype using 0.075% citrate buffer solution at pH 5.0 in this test, was approximately the same as that of the previous prototype using 0.075% citrate buffer solution at pH 5.0.

[0400] Furthermore, for Cont (2), a prototype using 0.1% citrate buffer solution at pH 5.0, the measured value of the [free chlorine concentration (assuming Cl = 35.45)] was lower than the [free chlorine concentration (assuming Cl = 35.45)] of the previous prototype using 0.1% citrate buffer solution at pH 5.0, but the residual rate was about the same. Based on these facts, it is believed that the results of the test conducted were sufficiently reproducible.

[0401] Results at D+150 <Up to D+180> As a result of storage at 40°C up to D+180, the prototype Cont (1), which uses 0.075% citrate buffer solution at pH 5.0, was stored at 40°C and at D+180, the [free chlorine concentration (assuming Cl=35.45)] was below 200 mg / L.

[0402] However, in this regard, just like the results up to D+150, the [free chlorine concentration (as Cl=35.45)] of the previous prototype using 0.075% citrate buffer solution at pH 5.0 was close to 200 mg / L at D+180 when stored at 40°C, and when the residual rate of [free chlorine concentration (as Cl=35.45)] was checked, it was found that even when stored at 40°C at D+180, the residual rate of [free chlorine concentration (as Cl=35.45)] of the previous 0.075% citrate buffer solution at pH 5.0 was about the same as the residual rate of Cont (1), the prototype using 0.075% citrate buffer solution at pH 5.0 in this test, and therefore it is determined that there is sufficient reproducibility.

[0403] Furthermore, for Cont (2), a prototype using 0.1% citrate buffer solution at pH 5.0, the free chlorine concentration (as Cl = 35.45) at D+180 after storage at 40°C was exactly 200 mg / L, which is lower than the free chlorine concentration (as Cl = 35.45) of the previous prototype using 0.1% citrate buffer solution at pH 5.0. However, the residual free chlorine concentration (as Cl = 35.45) of Cont (2), a prototype using 0.1% citrate buffer solution at pH 5.0 in this test, was similar to the residual free chlorine concentration (as Cl = 35.45) of the previous prototype using 0.1% citrate buffer solution at pH 5.0.

[0404] Based on the above, prototypes using phosphate buffer (current) and citrate buffer were stored at 40°C for 180 days, and the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] were checked. As a result, it was found that the prototype using citrate buffer was able to maintain the [free chlorine concentration (as Cl = 35.45)] for a longer period than the phosphate buffer (current), and the [free chlorine concentration (as Cl = 35 The changes over time in [content (as HClO2 = 68.46)] and [content (as chlorous acid (HClO2 = 68.46)] over a 180-day storage period at 40°C showed similar trends to the results of previous storage tests. Therefore, it has been determined that the reproducibility of this test is sufficient, and it has once again been demonstrated that a citrate buffer is more suitable than the current 0.1 mol / L phosphate buffer at pH 5.0 as a buffer for use with high-concentration hypochlorous acid water preparations (8,000 ppm product).

[0405] Results as of D+180 ◆Changes over time in the content (as chlorous acid (HClO2 = 68.46)) (※2) of each prototype using hypochlorous acid water as a raw material *2) Value obtained by iodometric titration (unit: ppm) *15) Value showing the percentage, with the value of D+0 being 100%.

[0406] Changes over time in the free chlorine concentration (based on Cl = 35.45) (*3) of each prototype using hypochlorous acid water as a raw material *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *15) Value shown as a percentage, with the value of D+0 being 100%.

[0407] [2] Raw materials used in hypochlorous acid water preparations (8,000 ppm product) <Up to D+30> First, with regard to the [content (as hypochlorous acid (HClO2 = 68.46))], the changes over time in the [content (as hypochlorous acid (HClO2 = 68.46))] of the prototypes using hypochlorous acid water as a raw material (Cont (1) to (2)) and the prototypes using hypochlorous acid = chlorine peroxide radical (ClOO.) as a raw material (Test (1) to (2), Test (5) to (6)) show similar trends. From this, it can be seen that there is no particular difference (no effect) in the [content (as hypochlorous acid (HClO2 = 68.46))] over time due to differences in raw materials.

[0408] However, on the other hand, with regard to the [free chlorine concentration (as Cl = 35.45)], whether 0.075% citrate buffer solution at pH 5.0 or 0.1% citrate buffer solution at pH 5.0 was used, the prototypes using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material (Tests (1)-(2), Tests (5)-(6)) maintained a higher [free chlorine concentration (as Cl = 35.45)], and it is thought that using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material may be able to generate [free chlorine concentration (as Cl = 35.45)] more efficiently.

[0409] Results as of D+30 <Up to D+90> As a result of storage at 40°C up to D+90, the free chlorine concentration (as Cl=35.45) was maintained at a higher level for the prototypes (Tests (1)-(2), Tests (5)-(6)) that used chlorous acid = chlorine peroxide radical (ClOO·) as a raw material, similar to the results up to D+30. However, the content (as chlorous acid (HClO2=68.46)) decreased slightly faster for the prototypes (Tests (1)-(2), Tests (5)-(6)) that used chlorous acid water as a raw material, and this test revealed that the difference in the residual rate of the content (as chlorous acid (HClO2=68.46)) was increasing over time compared to the prototypes (Tests (1)-(2)) that used chlorous acid water as a raw material.

[0410] Therefore, as reference data, the amount of free chlorine concentration (as Cl = 35.45) generated (per 1000 ppm) relative to the amount of consumed [content (as chlorous acid (HClO2 = 68.46))] up to D+90 for each prototype was calculated from the results up to D+90 when stored at 40°C, and then confirmed and compared.

[0411] The results showed that, whether 0.075% citrate buffer solution at pH 5.0 or 0.1% citrate buffer solution at pH 5.0 was used, the prototypes using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material (Tests (1) to (2), Tests (5) to (6)) produced a greater amount of [free chlorine concentration (as Cl = 35.45)] than the prototypes using chlorous acid water as the raw material (Cont. (1) to (2)). This trend, similar to the results up to D+30, suggests that using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material may be able to produce [free chlorine concentration (as Cl = 35.45)] more efficiently.

[0412] Results as of D+90 <Up to D+120> When stored at 40°C, the results up to D+120 showed that the prototypes (Tests (1)-(2), Tests (5)-(6)) that used chlorous acid = chlorine peroxide radical (ClOO.) as a raw material maintained a higher [free chlorine concentration (as Cl = 35.45)] than the prototypes (Cont (1)-(2)) that used chlorous acid water as a raw material, similar to the results up to D+90. However, the [content (as chlorous acid (HClO2 = 68.46))] decreased more quickly than the prototypes (Cont (1)-(2)) that used chlorous acid water as a raw material.

[0413] Therefore, the amount of [free chlorine concentration (as Cl = 35.45)] generated (per 1000 ppm) relative to the amount of [content (as chlorous acid (HClO2 = 68.46))] consumed for each prototype up to D+120 was calculated and compared. When stored at 40°C and compared, it was found that even at D+120, the prototypes using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material (Tests (1) to (2), Tests (5) to (6)) generated a greater amount of [free chlorine concentration (as Cl = 35.45)] than the prototypes using chlorous acid water as the raw material (Cont. (1) to (2)). As a trend, similar to the results up to D+90, there continues to be a trend that using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material can generate [free chlorine concentration (as Cl = 35.45)] more efficiently. (However, the prototype using chlorous acid = chlorine peroxide radical (ClOO.) as a raw material is simply able to produce a greater amount of free chlorine (as Cl = 35.45) than the amount consumed (as chlorous acid (HClO2 = 68.46)), and the fact remains that the amount consumed (as chlorous acid (HClO2 = 68.46)) is faster than the prototype using chlorous acid water as a raw material.)

[0414] Results as of D+120 <Up to D+150> In the results up to D+150 after storage at 40°C, the free chlorine concentration (as Cl=35.45) of the prototypes (Tests (1)-(2), Tests (5)-(6)) that used chlorous acid = chlorine peroxide radical (ClOO.) as a raw material was maintained at a higher value than the prototypes (Cont (1)-(2)) that used chlorous acid water as a raw material, similar to the results up to D+120. However, the content (as chlorous acid (HClO2=68.46)) also decreased more quickly than the prototypes (Cont (1)-(2)) that used chlorous acid water as a raw material, similar to the results up to D+120.

[0415] Therefore, we calculated the amount of [free chlorine concentration (as Cl = 35.45)] generated (per 1000 ppm) in relation to the amount of [content (as chlorous acid (HClO2 = 68.46))] consumed for each prototype up to D+150 (stored at 40°C) and compared them.Although this was only for prototypes made by "direct blending," it was found that "the prototypes using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material generated a greater amount of [free chlorine concentration (as Cl = 35.45)] than the prototypes using chlorous acid water as the raw material (Cont (1) - (2))," and the trend that "using chlorous acid = chlorine peroxide radical (ClOO·) as a raw material may be able to generate [free chlorine concentration (as Cl = 35.45)] more efficiently" continues to be observed. (However, the prototype using chlorous acid = chlorine peroxide radical (ClOO.) as a raw material is simply able to produce more [free chlorine concentration (as Cl = 35.45)] than the consumed [content (as chlorous acid (HClO2 = 68.46))], and as with the results up to D+120, it remains the same in that the [content (as chlorous acid (HClO2 = 68.46))] is consumed more quickly than the prototype using chlorous acid water as a raw material.)

[0416] Results as of D+150 <Up to D+180> Results up to D+180 after storage at 40°C showed that the measured values ​​of the [free chlorine concentration (as Cl=35.45)] of the prototypes (Tests (1)-(2), Tests (5)-(6)) using chlorous acid = chlorine peroxide radical (ClOO.) as a raw material tended to be higher than the prototypes (Cont (1)-(2)) using chlorous acid water formulation as a raw material, similar to the results up to D+150. However, on the other hand, the [content as chlorous acid (HClO2=68.46)] also decreased more quickly than the prototypes (Cont (1)-(2)) using chlorous acid water as a raw material, similar to the results up to D+150.

[0417] Therefore, when stored at 40°C and at D+180, the amount of [free chlorine concentration (as Cl = 35.45)] generated (per 1000 ppm) relative to the amount of [content (as chlorous acid (HClO2 = 68.46))] consumed up to D+180 for each prototype was calculated and compared. Although this was only for prototypes made by "direct blending," it was found that the tendency that "the amount of [free chlorine concentration (as Cl = 35.45)] generated was greater for prototypes using chlorous acid = chlorine peroxide radical (ClOO.) as a raw material (Test (1) to (2)) than for prototypes using chlorous acid water as a raw material (Cont (1) to (2))" continued to be seen up to D+180.

[0418] Based on the above, the prototypes (Test (1)-(2), Test (5)-(6)) made using chlorous acid = chlorine peroxide radical (ClOO·) as a raw material and the prototypes (Cont (1)-(2)) made using chlorous acid water were stored at 40°C for 180 days, and the changes in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46)] over time were confirmed. As a result, the [free chlorine concentration] of the prototypes (Test (1)-(2), Test (5)-(6)) made using chlorous acid = chlorine peroxide radical (ClOO·) as a raw material and the prototypes (Cont (1)-(2)) made using chlorous acid water were confirmed. The changes over time in the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)) show roughly similar trends, but the prototypes made using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material (Tests (1) to (2), Tests (5) to (6)) produced a slightly greater amount of free chlorine concentration (as Cl = 35.45) relative to the content (as chlorous acid (HClO2 = 68.46)) consumed, indicating that using chlorous acid = chlorine peroxide radical (ClOO·) as the raw material may enable more efficient generation of free chlorine concentration (as Cl = 35.45).

[0419] However, the prototype using chlorous acid = chlorine peroxide radical (ClOO.) as a raw material is simply able to produce more [free chlorine concentration (as Cl = 35.45)] than the consumed [content (as chlorous acid (HClO2 = 68.46))], and it still consumes [content (as chlorous acid (HClO2 = 68.46))] more quickly than the prototype using hypochlorous acid water as a raw material.

[0420] From this, we have now discovered that using chlorous acid = chlorine peroxide radical (ClOO·) as a raw material results in faster consumption of [chlorous acid content (HClO2 = 68.46)].

[0421] Results as of D+180 ◆Changes over time in the content (as chlorous acid (HClO2 = 68.46)) (*2) of each prototype using different raw materials and 0.075% citrate buffer solution at pH 5.0

[0422] *2) Value obtained by iodometric titration (unit: ppm) *15) Value showing the percentage, with the value of D+0 being 100%.

[0423] ◆Changes over time in the content (as chlorous acid (HClO2 = 68.46)) of each prototype using different raw materials and a 0.1% citrate buffer solution at pH 5.0 (*2) *2) Value obtained by iodometric titration (unit: ppm) *15) Value showing the percentage, with the value of D+0 being 100%.

[0424] ◆Changes over time in the free chlorine concentration (assuming Cl = 35.45) (*3) of each prototype using different raw materials and 0.075% citrate buffer solution at pH 5.0 *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *15) Value shown as a percentage, with the value of D+0 being 100%.

[0425] ◆Changes over time in the free chlorine concentration (based on Cl = 35.45) (*3) of each prototype using different raw materials and a 0.1% citrate buffer solution at pH 5.0 *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *15) Value shown as a percentage, with the value of D+0 being 100%.

[0426] ◆The amount of free chlorine (as Cl = 35.45) produced (mg / L) relative to the amount of chlorous acid (HClO2 = 68.46) consumed for various prototypes using different raw materials and 0.075% citrate buffer solution at pH 5.0 or 0.1% citrate buffer solution at pH 5.0 (*17) *17) Formula for calculating the amount of [free chlorine concentration (as Cl = 35.45)] generated (per 1000 ppm) (mg / L) relative to the amount of [content (as chlorous acid (HClO2 = 68.46))] consumed up to D+180: Amount of [free chlorine concentration (as Cl = 35.45)] generated (per 1000 ppm) relative to the amount of [content (as chlorous acid (HClO2 = 68.46)] consumed up to D+180 (mg / L) = {[free chlorine concentration (as Cl = 35.45)] at D+180 - [free chlorine concentration (as Cl = 35.45)] at the beginning (D+0)} / {[content (as chlorous acid (HClO2 = 68.46)] at D+180 - [content (as chlorous acid (HClO2 = 68.46)] at the beginning (D+0)} * 1000

[0427] [3] Formulation and method of hypochlorous acid water preparation (8,000 ppm product) <Until D+30> Based on the results up to now (storage at 40°C, as of D+30), the prototypes made by "direct blending" (Test (1) to Test (4)) and the prototypes made by "indirect blending" (Test (5) to (8)) show similar trends in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as hypochlorous acid (HClO2 = 68.46))], and it can be seen that there is no difference (no effect) in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as hypochlorous acid (HClO2 = 68.46))] due to differences in the formulation and method.

[0428] <Up to D+90> In the results up to D+90 when stored at 40°C, the same trend as the results up to D+30 was observed. Furthermore, in the actual measured values ​​of the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46)]] of the prototypes made by "direct blending" (Tests (1) to (4)) and the prototypes made by "indirect blending" (Tests (5) to (8)), it appears that the prototypes made by "direct blending" (Tests (1) to (4)) are able to maintain a higher [free chlorine concentration (as Cl = 35.45)], but in the residual rate of [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46)], no significant difference was observed between the prototypes made by "direct blending" (Tests (1) to (4)) and the prototypes made by "indirect blending" (Tests (5) to (8)).

[0429] <Up to D+120> In the results up to D+120 after storage at 40°C, the prototypes made using the "direct blending" method (Test (1) to Test (4)) maintained higher measured values ​​of [free chlorine concentration (as Cl = 35.45)] and residual rate than the prototypes made using the "indirect blending" method (Test (5) to (8)). However, the difference is slight, and although we will check whether this difference will become larger after D+120, we have determined that at this point (storage at 40°C, as of D+120), there is no particularly noticeable difference in the change over time in [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] between the prototypes made using the "direct blending" method (Test (1) to Test (4)) and the prototypes made using the "indirect blending" method (Test (5) to (8)).

[0430] <Up to D+150> In the results up to D+150 after storage at 40°C, similar to the results up to D+120 after storage at 40°C, the prototypes made using the "direct blending" method (Test (1) to Test (4)) had higher measured values ​​of [free chlorine concentration (as Cl = 35.45)] than the prototypes made using the "indirect blending" method (Test (5) to (8)). They also maintained a high residual rate. However, because this difference is smaller than the results after storage at 40°C at D+120, we have concluded that even at this point (40°C storage, D+150), there is no significant difference in the change over time in [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] between the prototypes made using the "direct blending" method (Test (1) to Test (4)) and the prototypes made using the "indirect blending" method (Test (5) to (8)).

[0431] <Up to D+180> As a result of storage at 40°C up to D+180, the prototype made using 0.075% citrate buffer solution at pH 5.0 was the only one in which the actual measured value of the [free chlorine concentration (as Cl = 35.45)] and the residual rate were maintained slightly higher for the prototype made using the "direct blending" method (Test (1)) than for the prototype made using the "indirect blending" method (Test (5)). However, for the prototypes using other buffer solutions, no differences were observed in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] between the prototypes made using the "direct blending" method (Test (2) to Test (4)) and the prototypes made using the "indirect blending" method (Test (6) to Test (8)).

[0432] Furthermore, even in the prototypes using 0.075% citrate buffer solution at pH 5.0, there was only a slight difference in the residual rate of the [free chlorine concentration (as Cl = 35.45)] in the prototype made by "direct blending" (Test (1)) and the [free chlorine concentration (as Cl = 35.45)] in the prototype made by "indirect blending" (Test (5)). Therefore, it was determined that there was no significant difference in the change over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] in the prototypes made by "direct blending" and "indirect blending."

[0433] Therefore, prototypes made using the "direct blending" method and prototypes made using the "indirect blending" method were stored at 40°C for 180 days, and the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] were checked.The results showed that, over a 180-day storage period at 40°C, there was no difference (no effect) in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] due to differences in the blending formula or method.

[0434] [4] Set pH of citrate buffer solution <up to D+30> First, the prototypes using citrate buffer solution of pH 5.0 (Test (1) to (2), Test (5) to (6)) maintain a higher [free chlorine concentration (as Cl = 35.45)] than the current product (Blank (1)), and also maintain a higher residual rate of [content (as chlorous acid (HClO2 = 68.46))] than the current product.

[0435] On the other hand, in the prototypes using a pH 6.0 citrate buffer solution (Tests (3) to (4), Tests (7) to (8)), the decrease in [content (as chlorous acid (HClO2 = 68.46))] is suppressed compared to the current product, but the [free chlorine concentration (as Cl = 35.45)] does not increase significantly after the initial test (D + 0), and by D + 30, it has already decreased to the same level as the [free chlorine concentration (as Cl = 35.45)] at the initial test (D + 0).

[0436] Based on the above, it is thought that it will be difficult to maintain the [free chlorine concentration (Cl = 35.45)] of the prototypes (Tests (3) to (4), Tests (7) to (8)) using a pH 6.0 citrate buffer solution at the same level until D+180. Assuming that it is better to be able to maintain the [free chlorine concentration (Cl = 35.45)] for a longer period than the current product, we believe that at the current time (stored at 40°C, as of D+30), a set pH of pH 5.0 for the citrate buffer solution would be better.

[0437] However, with regard to the concentration of the pH 5.0 citrate buffer, we believe that it is not possible to determine from the results up to now (storage at 40°C, D+30) whether 0.075% citrate buffer or 0.1% citrate buffer is better, so we will continue to confirm this while continuing the storage test.

[0438] Results at D+30 <Up to D+90> From the results up to D+90 when stored at 40°C, it was found that for all prototypes using pH 6.0 citrate buffer (Tests (3) to (4), Tests (7) to (8)), the free chlorine concentration (assuming Cl = 35.45) at D+90 when stored at 40°C fell below the initial value (D+0).

[0439] Therefore, this time, the [free chlorine concentration (assuming Cl = 35.45)] of each prototype was plotted from the point at which it reached its maximum value (storage at 40°C, time D+20) to create an approximate straight line, and the number of days until the [free chlorine concentration (assuming Cl = 35.45)] of each prototype reached 200 mg / L was calculated.

[0440] As a result, it was found that the number of days until the [free chlorine concentration (based on Cl = 35.45)] reached 200 mg / L was shorter (faster) for the prototypes using a pH 6.0 citrate buffer (Tests (3)-(4), Tests (7)-(8)) than for the prototypes using a pH 5.0 citrate buffer (Tests (1)-(2), Tests (5)-(6)). Furthermore, it was calculated that the number of days until the [free chlorine concentration (based on Cl = 35.45)] reached 200 mg / L for the prototypes using a pH 6.0 citrate buffer (Tests (3)-(4), Tests (7)-(8)) would all be around D+120 when stored at 40°C.

[0441] Based on the above, it can be concluded that the prototypes using a pH 6.0 citrate buffer solution (Tests (3)-(4), Tests (7)-(8)) can maintain a free chlorine concentration (based on Cl = 35.45) for longer than the current product, but cannot maintain a free chlorine concentration (based on Cl = 35.45) of 200 mg / L or more until D+180 when stored at 40°C.

[0442] Furthermore, calculations have shown that the prototypes using a pH 5.0 citrate buffer solution (Tests (1)-(2), Tests (5)-(6)) may not be able to maintain a free chlorine concentration (based on Cl = 35.45) of 200 mg / L or more up to D+180 when stored at 40°C. However, it is clear that they maintain a higher free chlorine concentration (based on Cl = 35.45) for a longer period than the prototypes using a pH 6.0 citrate buffer solution (Tests (3)-(4), Tests (7)-(8)).

[0443] Therefore, we believe that a pH of 5.0 is a better setting for the citrate buffer solution in order to maintain the free chlorine concentration (assuming Cl = 35.45) for a long period of time.

[0444] However, with regard to the concentration of the pH 5.0 citrate buffer, at D+90 after storage at 40°C, no significant differences were observed in the changes over time in the [free chlorine concentration (as Cl=35.45)] and [content (as chlorous acid (HClO2=68.46))] between the prototypes using 0.075% citrate buffer at pH 5.0 (Test (1) and Test (5)) and the prototypes using 0.1% citrate buffer at pH 5.0 (Test (2) and Test (6)). As such, it is not possible to determine from the results up to this point (storage at 40°C, at D+90) whether a better concentration is used, 0.075% citrate buffer or 0.1% citrate buffer, and storage tests will continue regarding the concentration of the citrate buffer.

[0445] ◆ Figure 12 shows the approximate line of the [free chlorine concentration (assuming Cl = 35.45)] for the prototypes using citrate buffer solution at pH 5.0 (Tests (1) to (2), Tests (5) to (6)) and the prototypes using citrate buffer solution at pH 6.0 (Tests (3) to (4), Tests (7) to (8)). ◆ The number of days for each prototype to reach 200 mg / L in [free chlorine concentration (assuming Cl = 35.45)] calculated from the approximate line. Results at D+90

[0446] <Up to D+120> From the results of storage at 40°C up to D+120, it was found that for most of the prototypes using pH 6.0 citrate buffer (Tests (3) to (4), Tests (7) to (8)), the free chlorine concentration (assuming Cl = 35.45) fell below 200 mg / L at D+120 when stored at 40°C.

[0447] From this, it became clear that with a citrate buffer solution of pH 6.0, the free chlorine concentration (assuming Cl = 35.45) cannot be maintained at 200 mg / L or more until D+180 when stored at 40°C, as soon as D+120 has passed.

[0448] Therefore, as already stated at D+90, we have determined that pH 5.0 is the appropriate pH for the citrate buffer solution.

[0449] In addition, because the [free chlorine concentration (assuming Cl = 35.45)] of the prototypes using pH 6.0 citrate buffer (Tests (3) to (4), Tests (7) to (8)) reached (fell below) 200 mg / L, a comparison was made between the (assumed) number of days until the [free chlorine concentration (assuming Cl = 35.45)] reached 200 mg / L at D+90 and the actual number of days when the [free chlorine concentration (assuming Cl = 35.45)] reached (or fell below) 200 mg / L, and it was found that the numbers of days were approximate.

[0450] From this, it can be considered that the number of days until the [free chlorine concentration (based on Cl = 35.45)] reaches 200 mg / L in the prototypes using a pH 5.0 citrate buffer solution (Tests (1)-(2), Tests (5)-(6)) is likely to be close to the (assumed) number of days calculated from the approximation line at D+90, and since the number of days until the [free chlorine concentration (based on Cl = 35.45)] reaches 200 mg / L calculated at D+90 was around D+180, it is believed that there is a good chance that the [free chlorine concentration (based on Cl = 35.45)] can be maintained at 200 mg / L or above for the period D+180 when stored at 40°C in the prototypes using a pH 5.0 citrate buffer solution (Tests (1)-(2), Tests (5)-(6)).

[0451] Regarding the concentration of the pH 5.0 citrate buffer, even at this time (storage at 40°C, D+120), no significant differences have been observed in the changes over time in the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)) between the prototypes using 0.075% citrate buffer at pH 5.0 (Test (1) and Test (5)) and the prototypes using 0.1% citrate buffer at pH 5.0 (Test (2) and Test (6)). Therefore, it is still not possible to determine which concentration of citrate buffer, 0.075% or 0.1%, can maintain the free chlorine concentration (as Cl = 35.45) for a longer period. Therefore, storage testing of the citrate buffer will continue. (However, if a determination cannot be made by D+180, we believe it will be necessary to continue the storage testing after D+180 until a determination can be made.)

[0452] *Comparison of the number of days assumed for the free chlorine concentration (assuming Cl = 35.45) to reach 200 mg / L and the number of days confirmed for the free chlorine concentration (assuming Cl = 35.45) to have actually reached (fallen below) 200 mg / L.

[0453] Results as of D+120 <Up to D+150> As a result of storing at 40°C up to D+150, the prototypes using pH 5.0 citrate buffer (Tests (1) to (2), Tests (5) to (6)) were able to maintain a [free chlorine concentration (assuming Cl = 35.45)] of 200 mg / L or more.

[0454] Furthermore, with regard to the concentration of the pH 5.0 citrate buffer, even at this time (stored at 40°C, D+150), no significant difference has been observed in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] between the prototypes using 0.075% citrate buffer at pH 5.0 (Test (1) and Test (5)) and the prototypes using 0.1% citrate buffer at pH 5.0 (Test (2) and Test (6)). Therefore, it is still difficult to determine which concentration of citrate buffer, 0.075% or 0.1%, can maintain the [free chlorine concentration (as Cl = 35.45)] for a longer period of time.

[0455] However, because the blending ratio of chlorous acid water formulations is calculated from the concentrations of the raw materials, chlorous acid = chlorine peroxide radical (ClOO·) (or chlorous acid water) and GB chlorine dioxide water, this test used chlorous acid = chlorine peroxide radical (ClOO·) that had been produced a few days earlier. However, if chlorous acid = chlorine peroxide radical (ClOO·) (or chlorous acid water) that has been produced for some time is used as a raw material, it is possible that the content (as chlorous acid (HClO2 = 68.46)) and free chlorine concentration (as Cl = 35.45) may have decreased, in which case the blending ratio of chlorous acid = chlorine peroxide radical (ClOO·) (or chlorous acid water) may be higher and the blending ratio of citrate buffer may be lower. (At the very least, the blending ratio of citrate buffer will be lower than immediately after production.)

[0456] Furthermore, considering that a prototype using a 0.05% citrate buffer solution at pH 5.0, which has a lower concentration than a 0.075% citrate buffer solution at pH 5.0, will have a free chlorine concentration (assuming Cl = 35.45) of below 200 mg / L at D+150 when stored at 40°C, we are considering selecting a 0.1% citrate buffer solution with a higher concentration for pH 5.0, in order to maintain the free chlorine concentration (assuming Cl = 35.45) for a long period of time, even if the citrate buffer content is lower.

[0457] Results at D+150 <Up to D+180> As a result of storage at 40°C up to D+180, most of the prototypes using pH 5.0 citrate buffer (Tests (1)-(2), Tests (5)-(6)) were able to maintain a [free chlorine concentration (assuming Cl=35.45)] of 200 mg / L or more.

[0458] Furthermore, with regard to the concentration of the pH 5.0 citrate buffer, even at D+180 after storage at 40°C, no significant differences were observed in the changes over time in the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)) between the prototypes using 0.075% citrate buffer at pH 5.0 (Test (1) and Test (5)) and the prototypes using 0.1% citrate buffer at pH 5.0 (Test (2) and Test (6)).

[0459] Furthermore, among the prototypes made by "indirect blending," Test (5), which is a prototype made using 0.075% citrate buffer solution at pH 5.0, has a free chlorine concentration (as Cl = 35.45) below 200 mg / L, but the residual rate of this free chlorine concentration (as Cl = 35.45) is not significantly different from the residual rate of the free chlorine concentration (as Cl = 35.45) of the prototype made using 0.1% citrate buffer solution at pH 5.0.

[0460] From the above, prototypes using citrate buffer solutions of each pH and concentration were stored at 40°C for 180 days. As a result, with regard to the pH of the citrate buffer solution, it was found that a citrate buffer solution of pH 6.0 could not maintain a [free chlorine concentration (assuming Cl = 35.45)] of 200 mg / L or more for 180 days when stored at 40°C, but that a citrate buffer solution of pH 5.0 could maintain a [free chlorine concentration (assuming Cl = 35.45)] of 200 mg / L or more for a period of D + 180 when stored at 40°C.

[0461] Based on this, we conclude that pH 5.0 is more suitable as the pH of the citrate buffer solution for maintaining the free chlorine concentration (assuming Cl = 35.45) for a long period of time.

[0462] Furthermore, with regard to the concentration of the pH 5.0 citrate buffer, there was no significant difference in the changes over time in the free chlorine concentration (as Cl = 35.45) and content (as chlorous acid (HClO2 = 68.46)) between the prototype using 0.075% citrate buffer and the prototype using 0.1% citrate buffer. However, it has already been confirmed that the 0.05% citrate buffer at pH 5.0, which has a lower concentration than the 0.075% citrate buffer at pH 5.0, cannot maintain a free chlorine concentration (as Cl = 35.45) of 200 mg / L or more for 180 days when stored at 40°C. Therefore, in order to maintain the free chlorine concentration (as Cl = 35.45) for a long period of time even if the blending ratio of the citrate buffer were to decrease, the 0.1% citrate buffer with a higher concentration was selected.

[0463] Therefore, in high-concentration chlorous acid water preparations (8,000 ppm product), a 0.1% citrate buffer solution with a pH of 5.0 is selected as the citrate buffer solution to maintain the free chlorine concentration (assuming Cl = 35.45) for a long period of time.

[0464] Results as of D+180 ◆Changes over time in the content (as chlorous acid (HClO2 = 68.46)) of a hypochlorous acid water preparation (direct blend) produced by directly adding hypochlorous acid = chlorine peroxide radical (ClOO·) as is (※2) *2) Value obtained by iodometric titration (unit: ppm) *15) Value showing the percentage, with the value of D+0 being 100%.

[0465] ◆Chlorous acid = Chlorine peroxide radical (ClOO·) and GB chlorine dioxide water are mixed to create chlorous acid water, which is then mixed with chlorous acid water (indirect blending). The change over time in the amount of chlorous acid (HClO2 = 68.46) (※2) *2) Value obtained by iodometric titration (unit: ppm) *15) Value showing the percentage, with the value of D+0 being 100%.

[0466] Changes over time in the free chlorine concentration (based on Cl = 35.45) (*3) of a hypochlorous acid solution (direct blend) prepared by directly adding hypochlorous acid = chlorine peroxide radical (ClOO·) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *15) Value shown as a percentage, with the value of D+0 being 100%.

[0467] Changes over time in the free chlorine concentration (based on Cl = 35.45) (*3) of a hypochlorous acid solution formulation (indirect blending) prepared by mixing hypochlorous acid (chlorine peroxide radicals (ClOO·)) with GB chlorine dioxide water and then adding the solution. *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *15) Value shown as a percentage, with the value of D+0 being 100%.

[0468] Regarding the contents of [1] to [4], the trends confirmed from the results up to D+180 when stored at 40°C

[0469] The above summarizes the trends that emerged from the investigation into the differences in the changes over time in the [free chlorine concentration (as Cl = 35.45)] and [content of chlorous acid (as HClO2 = 68.46)] when prototypes with different buffer solutions, raw materials, formulations and methods (direct and indirect formulation), and buffer solution pH were prepared and stored at 40°C for 180 days.

[0470] Furthermore, from the results of [4], it has been confirmed that a pH 6.0 citrate buffer solution cannot maintain a free chlorine concentration (assuming Cl = 35.45) of 200 mg / L or more for 180 days when stored at 40°C. Therefore, it has already been determined that it is not suitable as a buffer solution for high-concentration chlorous acid water preparations (8,000 ppm product).

[0471] However, from the trends in the [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46))] up to D+180 when stored at 40°C, it can be seen that although the [content (as chlorous acid (HClO2 = 68.46))] of the prototype using pH 6.0 citrate buffer was relatively maintained at D+180 when stored at 40°C, its [free chlorine concentration (as Cl = 35.45)] was below 200 mg / L, and it is thought that the prototype using pH 6.0 citrate buffer was not able to replenish the [free chlorine concentration (as Cl = 35.45)] from the [content (as chlorous acid (HClO2 = 68.46))].

[0472] From this, it can be seen that the prototype using a pH 6.0 citrate buffer solution does not function well in the first place in the cycle reaction of hypochlorous acid water, and therefore, although the content (as hypochlorous acid (HClO2 = 68.46)) is relatively maintained, it is thought that the free chlorine concentration (as Cl = 35.45) cannot be maintained high for a long period of time.

[0473] In addition, high-concentration hypochlorous acid water preparations (8,000 ppm products) are guaranteed to have a free chlorine concentration (based on Cl = 35.45) of 200 mg / L or more, and so are based on the premise that the free chlorine concentration (based on Cl = 35.45) is maintained at 200 mg / L or more. Considering this, citrate buffer solution at pH 6.0 not only loses its function as hypochlorous acid water (cycle reaction), but is also unable to maintain the free chlorine concentration (based on Cl = 35.45) at 200 mg / L or more, it can be seen that a citrate buffer solution at pH 6.0 is not suitable as a citrate buffer solution for use with high-concentration hypochlorous acid water preparations (8,000 ppm products).

[0474] Furthermore, the prototype using pH 5.0 citrate buffer had a lower [content (as chlorous acid (HClO2 = 68.46)] at D+180 when stored at 40°C compared to the prototype using pH 6.0 citrate buffer, but was able to maintain a [free chlorine concentration (as Cl = 35.45)] of 200 mg / L or more. This shows that the [content (as chlorous acid (HClO2 = 68.46)]] is able to fully replenish the [free chlorine concentration (as Cl = 35.45)], and that with pH 5.0 citrate buffer, the chlorous acid water cycle reaction functions properly and the [free chlorine concentration (as Cl = 35.45)] can be maintained at 200 mg / L or more for 180 days when stored at 40°C. (The following are excerpts from the actual measurements and residual rates of [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46)] at D+180 after storage at 40°C.)

[0475] From the above, it can be seen that a citrate buffer solution of pH 5.0 is suitable as a citrate buffer solution for maintaining the free chlorine concentration (Cl = 35.45) for a long period of time in a high-concentration chlorous acid water preparation (8,000 ppm product) that uses chlorous acid = chlorine peroxide radical (ClOO ). As described above in [4], a 0.1% citrate buffer solution of pH 5.0 was selected, and for the chlorous acid water preparation (8,000 ppm product) using a citrate buffer solution, a new formulation of a chlorous acid water preparation (8,000 ppm product) was planned based on the results of this test.

[0476] Measurement results of [free chlorine concentration (as Cl = 35.45)] and [content (as chlorous acid (HClO2 = 68.46)]] at D+180 for hypochlorous acid water preparations (direct blending) using citrate buffer solutions of each pH and concentration *2) Value obtained by iodometric titration (unit: ppm) *3) Value obtained by colorimetric method (DPD method) (unit: mg / L) *15) Values ​​shown as percentages, with the value of D+0 being 100%

[0477] Graphs of the change over time in the free chlorine concentration (based on Cl = 35.45) for each prototype (up to D+180) are shown in Figures 13-1 to 13-3. (X indicates a prototype whose free chlorine concentration (based on Cl = 35.45) was below 200 mg / L at D+180.)

[0478] ◆Graphs of the change over time in the content (as chlorous acid (HClO2 = 68.46)) of each prototype (up to D+180) are shown in Figures 14-1 to 14-3. (X indicates a prototype whose free chlorine concentration (as Cl=35.45) was below 200 mg / L at D+180.)

[0479] For high-concentration hypochlorous acid water formulations (8000 ppm (0.8 wt%)), by using a 0.1% citrate buffer solution set to pH 5.0, it was possible to maintain a free chlorine concentration (assuming Cl = 35.45) of 200 mg / L or higher for 180 days (equivalent to more than 3 years at room temperature), even under the harsh conditions of 40°C. This formulation was found to be the optimal condition for high-concentration hypochlorous acid water formulations.

[0480] The substance detected as the free chlorine concentration among the chlorine components contained in hypochlorous acid water is the chlorine peroxide radical, which is the active species of chlorous acid, the main active ingredient in hypochlorous acid water. The fact that this value is maintained means that phosphate buffer and citrate buffer are able to convert this chlorine peroxide radical into chlorite ions (H + ClO2 - This not only allows the cycle reaction that regenerates the chlorine peroxide radical to proceed smoothly and slowly, but also prevents the deterioration of chemical quality caused by the gasification and disappearance of the chlorine peroxide radical. This effect is thought to be more pronounced with citrate buffer than with phosphate buffer (Figure 15).

[0481] This effect of buffers such as citric acid and phosphate directly influencing the cycle reaction of hypochlorous acid water, making the reaction smooth and slow, has not been reported until now. As a result, we believe that technology that can bring out the effect of maintaining the bactericidal power of the substance hypochlorous acid (HClO2) will be extremely beneficial for industrial use in on-site environments.

[0482] As described above, the present invention has been illustrated using preferred embodiments thereof, but it should be understood that the scope of the present invention should be construed solely in accordance with the claims. This application claims priority to Japanese Patent Application No. 2024-78765 (filed May 14, 2024), the contents of which are incorporated herein by reference in their entirety. It is understood that the patents, patent applications, and other documents cited herein are incorporated herein by reference in their entirety as if the contents themselves were specifically set forth herein.

[0483] Provided is a method for producing a chlorous acid water preparation capable of maintaining chlorous acid water, its main active ingredient chlorous acid, and its active molecular species, chlorine peroxide radicals, in a liquid state at room temperature for three years or more in a high-concentration range or a low-concentration range.

Claims

1. A method for producing a chlorous acid water formulation with a predetermined content (as chlorous acid (HClO2 = 68.46)), comprising: (1) preparing a buffer solution; (2) determining the concentration of the buffer solution; (3) preparing chlorous acid water; (4) determining the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)); (5) determining the amount of the buffer solution to be used for dilution from the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) and the predetermined content (as chlorous acid (HClO2 = 68.46)); and (6) diluting the chlorous acid water with the amount of the buffer solution to produce a chlorous acid water formulation with the predetermined content (as chlorous acid (HClO2 = 68.46)).

2. The method of claim 1, wherein the buffer is a citrate buffer, a phosphate buffer, or a mixture thereof.

3. The method of claim 2, wherein the content of the chlorous acid water (as chlorous acid (HClO2 = 68.46)) is 4.0% to 6.0% by weight.

4. The manufacturing method according to claim 3, wherein the concentration of the citrate buffer is 0.01% (0.52 mmol / L as citric acid) to 1% (52 mmol / L as citric acid).

5. The method of claim 3, wherein the concentration of the phosphate buffer solution is 0.098% (0.01 mol / L as phosphoric acid) to 9.8% (1 mol / L as phosphoric acid).

6. The method of claim 4, wherein the liquid ratio of the chlorous acid water to the citrate buffer solution is 9:1 to 1:

9.

7. The manufacturing method according to claim 6, wherein when a citrate buffer solution is used, the liquid ratio of the citrate buffer solution to the chlorous acid solution may be 1 part or more or 1 part or less, and the liquid ratio of the citrate buffer solution to the chlorous acid solution is 999:1 to 1:

999.

8. The method of claim 5, wherein the liquid ratio of the chlorous acid water to the phosphate buffer solution is 1:1 to 1:

9.

9. The manufacturing method according to claim 8, wherein when a phosphate buffer solution is used, the liquid ratio of the phosphate buffer solution to the chlorous acid water is 1:1 or more, specifically, the liquid ratio of the chlorous acid water to the phosphate buffer solution is 1:2 to 1:

999.

10. The manufacturing method described in claim 1, wherein the predetermined concentration of the hypochlorous acid water is 1000 ppm or more.

11. The manufacturing method according to claim 1, wherein the predetermined concentration of the chlorous acid water is less than 1000 ppm.

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