Composition for sterilization and sterilization method

Abstract

To provide a disinfection composition that is suitable for users, including general consumers, to perform bacteria eradication, antibacterial measures, sterilization, or disinfection, wherein the disinfection composition has a pH of 12 or less, tends not to roughen hand skin, and has high storage stability, and to provide a disinfection method using the disinfection composition.SOLUTION: A disinfection composition contains a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid; has an effective bromine concentration that falls within the range of 0.01-0.25%; and a pH that falls within the range between 5.0 and 11.0.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a sterilizing composition for performing sterilization, antibacterial, disinfection, or sterilization of an object to be sterilized, and a sterilization method for performing sterilization, antibacterial, disinfection, or sterilization of an object to be sterilized using the sterilizing composition.

Background Art

[0002] The novel coronavirus (CoVid-19), which has been rapidly spreading since the end of 2019 to the present, has become a historical pandemic. Due to this event, consumer behavior has changed significantly. Especially in homes, restaurants, etc., consumers have taken the initiative to perform sterilization, antibacterial, disinfection, or sterilization on various places such as the walls, doors, floors, furniture, kitchen sinks, washing machines, bathrooms, kitchens, dining tables, chairs, etc.

[0003] As effective sterilization, antibacterial, disinfection, or sterilization methods, in Japan, sufficient supply is possible, and as effective chemical substances, sodium hypochlorite and ethanol can be mentioned. Furthermore, in the "Evaluation of the effectiveness of alternative disinfection methods against the novel coronavirus (Final Report)" published by the National Institute of Technology and Evaluation (NITE) in Japan in June 2020, various surfactants, soaps, hypochlorous acid water, sodium dichloroisocyanurate, etc. are also said to be effective.

[0004] However, when users including general consumers handle these substances by themselves, there are various risks. For example, ethanol is effective against viruses with an envelope such as the novel coronavirus (CoVid-19), but it does not work effectively against viruses without an envelope, such as norovirus.

[0005] Regarding sodium hypochlorite, many commercially available products have an available chlorine concentration of about 6 to 12% by weight (60,000 to 120,000 mgCl / L). When users including general consumers use this, there is a risk of generating chlorine gas by mixing with an acid, and even in dilution with water, due to concentration adjustment errors, there is a risk of insufficient effect due to low concentration or various adverse effects due to high concentration. Adverse effects due to high concentration include discomfort due to the odor of chlorine gas in a confined space, corrosion due to contact with metal objects, skin irritation to the human body, etc. Also, even if sodium hypochlorite can be adjusted to a concentration of 0.05% by weight (500 mgCl / L) or more recommended in the "List of Disinfection and Sterilization Methods Effective against Novel Coronavirus" published by the Ministry of Economy, Trade and Industry of Japan on July 6, 2020, there is a risk of discomfort due to the odor of chlorine gas during wiping and cleaning.

[0006] Regarding sodium dichloroisocyanurate which is a solid, essentially it has the same risks as sodium hypochlorite. Regarding hypochlorous acid water, in the above report of NITE, it is said to be effective against the novel coronavirus (CoVid-19) at an available chlorine concentration of 35 mgCl / L or more. However, it is difficult for commercially available hypochlorous acid water to stably maintain an available chlorine concentration of 35 mgCl / L or more for a long time, and there is a risk of reaching a concentration with insufficient effect. Also, in the above report of the Ministry of Economy, Trade and Industry, for "wiping and cleaning" using hypochlorous acid water, it recommends an available chlorine concentration of 80 mgCl / L or more, but in practice, there is a problem that it is very difficult to supply while maintaining an available chlorine concentration of 80 mgCl / L or more.

[0007] Although surfactants and soaps have a certain effect, the usage concentration at which the effect is recognized is as high as about 0.1% by weight or more, and it is difficult to instantaneously perform sterilization, antibacterial, disinfection, or sterilization. Moreover, since their wastewater imposes a large environmental burden, it cannot be said that their use is preferable.

[0008] Thus, when users including general consumers use existing recommended chemical substances for the purpose of sterilization, antibacterial, disinfection, or sterilization, they have some risks or problems.

[0009] On the one hand, Patent Document 1 describes a water treatment agent composition containing water, a bromine-based oxidizing agent with an available bromine concentration of 1 to 16.5% by mass as the concentration of available bromine with respect to the total amount of the water treatment agent composition, sulfamic acid in an amount of 0.7 to 2.0 times the molar amount of the bromine-based oxidizing agent, and an alkali containing at least one of sodium hydroxide and potassium hydroxide, having a pH of 12.5 or higher, and a water concentration of 54% by mass or higher with respect to the total amount of the water treatment agent composition.

[0010] However, when the above available bromine concentration is converted to an available chlorine concentration, it is as high as 4400 mgCl / L to 73300 mgCl / L, and the pH is 12.5 or higher. When the water treatment agent composition of Patent Document 1 is used by users including general consumers for disinfection, antibacterial, sterilization, or disinfection, the risk of roughness and other problems increases. Further, in the study by the present inventors, it was found that the water treatment agent composition of Patent Document 1 also has a problem of insufficient storage stability at a pH suitable for use by users including general consumers.

[0011] In addition, in order to safely deliver to users including general consumers, it is desirable to dilute and provide such a high-concentration oxidizing agent. Further, in the diluted solution, since roughness occurs when the pH is higher than 12, it is better to adjust the pH to 12 or lower. However, oxidizing agents such as stabilized hypobromous acid and sodium hypochlorite are stable on the alkaline side, but there is a possibility of generating halogen gas when they become acidic, and they are not stable.

Prior Art Documents

Patent Documents

[0012]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0013] An object of the present invention is to provide a sterilizing composition suitable for use by users including general consumers for sterilization, antibacterial, disinfection, or sterilization, which is less likely to cause rough hands with a pH of 12 or less and has high storage stability, and a sterilizing method using the sterilizing composition.

Means for Solving the Problems

[0014] The present invention is a sterilizing composition containing a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid, having an available bromine concentration in the range of 0.01% or more and 0.25% or less, and a pH in the range of 5.0 to 11.0.

[0015] The present invention is a sterilizing composition containing a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid, having an available bromine concentration in the range of 0.011% or more and 0.225% or less, and a pH in the range of 5.0 to 10.5.

[0016] In the sterilizing composition, it is preferable that the strong acid contains at least one strong acid among sulfuric acid, hydrochloric acid, and nitric acid.

[0017] In the sterilizing composition, it is preferable to contain 1.0 to 2.0 times the equivalent amount of the sulfamic acid compound with respect to the equivalent amount of the bromine-based oxidizing agent.

[0018] In the sterilizing composition, it is preferable that the bromine-based oxidizing agent is bromine.

[0019] The present invention is a sterilizing method in which the sterilizing composition is added to an object to be sterilized so that the total halogen residue is in the range of 0.00002% to 0.23% of the available bromine concentration.

Effects of the Invention

[0020] According to the present invention, it is possible to provide a sterilizing composition suitable for use by users including general consumers for sterilization, antibacterial, disinfection, or sterilization, which is less likely to cause rough hands with a pH of 12 or less and has high storage stability, and a sterilizing method using the sterilizing composition.

Brief Description of the Drawings

[0021]

Figure 1

Mode for Carrying Out the Invention

[0022] The embodiments of the present invention will be described below. This embodiment is an example of carrying out the present invention, and the present invention is not limited to this embodiment.

[0023] <Sterilization Composition> The sterilization composition according to the embodiment of the present invention contains a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid, and has an available bromine concentration in the range of 0.01% or more and 0.25% or less, and a pH in the range of 5.0 to 11.0. Further, the sterilization composition according to the embodiment of the present invention contains a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid, and is a sterilization composition having an available bromine concentration in the range of 0.011% or more and 0.225% or less, and a pH in the range of 5.0 to 10.5.

[0024] As a result of intensive studies, the present inventors have found that when the effective halogen concentration exceeds a certain level, the storage stability decreases. Through further studies, it has been found that by adding a strong acid at a pH of 5.0 or more and 11.0 or less, the storage stability is significantly improved. The sterilization composition according to this embodiment is suitable for users including general consumers to perform disinfection, antibacterial, disinfection, or sterilization, is less likely to cause rough skin at a pH of 12 or less, and has high storage stability. The sterilization composition according to this embodiment is a stabilized hypobromite-based solution, and can achieve long-term storage stability, which could not be achieved with conventional aqueous sodium hypochlorite solutions. In addition, it has a very high disinfection effect, antibacterial effect, disinfection effect, or sterilization effect not only against viruses with envelopes such as the novel coronavirus (CoVid-19), but also against viruses without envelopes such as norovirus, which could not be achieved with conventional high-concentration ethanol solutions.

[0025] "Comprising a bromine-based oxidizing agent and a sulfamic acid compound" may include a stabilized hypobromous acid composition containing a mixture of a "bromine-based oxidizing agent" and a "sulfamic acid compound", or may include a stabilized hypobromous acid composition containing a "reaction product of a bromine-based oxidizing agent and a sulfamic acid compound".

[0026] Examples of the bromine-based oxidizing agent include bromine (liquid bromine), bromine chloride, bromic acid, bromate, hypobromous acid, etc. Hypobromous acid may be produced by reacting a bromine compound such as sodium bromide with a chlorine-based oxidizing agent such as hypochlorous acid.

[0027] Among these, a composition containing "bromine and a sulfamic acid compound (a mixture of bromine and a sulfamic acid compound)" or a "reaction product of bromine and a sulfamic acid compound" using bromine is more preferable as a bactericidal composition because it produces less by-product bromic acid and has lower corrosivity to metals compared to a composition of "bromine compound, hypochlorous acid, and sulfamic acid", etc.

[0028] Examples of the bromine compound include sodium bromide, potassium bromide, lithium bromide, ammonium bromide, and hydrobromic acid. Among these, sodium bromide is preferable from the viewpoint of formulation cost, etc.

[0029] Examples of the chlorine-based oxidizing agent include chlorine gas, chlorine dioxide, hypochlorous acid or its salts, chlorous acid or its salts, chloric acid or its salts, perchloric acid or its salts, chlorinated isocyanuric acid or its salts, and the like. Among these, examples of the salts include alkali metal hypochlorites such as sodium hypochlorite and potassium hypochlorite, alkaline earth metal hypochlorites such as calcium hypochlorite and barium hypochlorite, alkali metal chlorites such as sodium chlorite and potassium chlorite, alkaline earth metal chlorites such as barium chlorite, other metal chlorites such as nickel chlorite, ammonium chlorate, alkali metal chlorates such as sodium chlorate and potassium chlorate, alkaline earth metal chlorates such as calcium chlorate and barium chlorate, and the like. These chlorine-based oxidizing agents may be used alone or in combination of two or more. From the viewpoints of handleability and the like, it is preferable to use sodium hypochlorite as the chlorine-based oxidizing agent.

[0030] The sulfamic acid compound is a compound represented by the following general formula (1). R2NSO3H (1) (In the formula, R is independently a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.)

[0031] Examples of sulfamic acid compounds include, in addition to sulfamic acid (amidosulfuric acid) in which both of the two R groups are hydrogen atoms, sulfamic acid compounds in which one of the two R groups is a hydrogen atom and the other is an alkyl group having 1 to 8 carbon atoms, such as N-methylsulfamic acid, N-ethylsulfamic acid, N-propylsulfamic acid, N-isopropylsulfamic acid, N-butylsulfamic acid, etc., sulfamic acid compounds in which both of the two R groups are alkyl groups having 1 to 8 carbon atoms, such as N,N-dimethylsulfamic acid, N,N-diethylsulfamic acid, N,N-dipropylsulfamic acid, N,N-dibutylsulfamic acid, N-methyl-N-ethylsulfamic acid, N-methyl-N-propylsulfamic acid, etc., sulfamic acid compounds in which one of the two R groups is a hydrogen atom and the other is an aryl group having 6 to 10 carbon atoms, such as N-phenylsulfamic acid, or salts thereof. Examples of sulfamate salts include alkali metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as calcium salt, strontium salt and barium salt, other metal salts such as manganese salt, copper salt, zinc salt, iron salt, cobalt salt and nickel salt, ammonium salt and guanidine salt. The sulfamic acid compound and these salts may be used alone or in combination of two or more. From the viewpoint of environmental load, etc., it is preferable to use sulfamic acid (amidosulfuric acid) as the sulfamic acid compound.

[0032] Examples of strong acids include inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, hydrogen iodide, perchloric acid, chloric acid, bromic acid, iodic acid, perbromic acid, etc. From the viewpoint of safety, etc., it is preferable to contain at least one strong acid selected from sulfuric acid, hydrochloric acid and nitric acid. The content of the strong acid in the sterilizing composition is, for example, in the range of 0.0001% by weight to 70% by weight, and preferably in the range of 0.001% by weight to 50% by weight.

[0033] The pH of the composition for sterilization is in the range of 5.0 to 11.0, or in the range of 5.0 to 10.5, preferably in the range of 5.5 to 10.7, and more preferably in the range of 6.0 to 10.5. If the pH of the composition for sterilization is less than 5.0, the storage stability decreases, and if it exceeds 11.0, it becomes a factor causing roughness during handling.

[0034] The amount of halogen gas generated after storing the composition for sterilization at 30 °C for 1 hour under sealing is preferably 0.05 mg / L or less, and more preferably 0.025 mg / L or less.

[0035] The available bromine concentration in the composition for sterilization is in the range of 0.01% to 0.25%, preferably in the range of 0.011% to 0.225%, and more preferably in the range of 0.0113% to 0.169%. If the available bromine concentration in the composition for sterilization is less than 0.01%, the bactericidal power significantly decreases and the storage stability also decreases. If it exceeds 0.25%, the stability significantly decreases. The available bromine concentration of the composition for sterilization, in terms of available chlorine concentration, is in the range of 45 - 1150 mgCl / L, preferably in the range of 50 - 1000 mgCl / L, and more preferably in the range of 50 - 750 mgCl / L.

[0036] In the water treatment agent composition described in Patent Document 1, it contains a bromine - based oxidizing agent with an available bromine concentration of 1 - 16.5 mass%. Since the molecular weight of bromine (Br2) is 159.8 and the molecular weight of chlorine (Cl2) is 70.9, when converted to the available chlorine concentration, 1% of the available bromine concentration is 1÷159.8×70.9 = 0.44% of the available chlorine concentration. Given that the available chlorine concentration in Patent Document 1 is 0.44% and the specific gravity is 1.0 g / mL, the 0.44% available chlorine concentration is (0.44 wt% = 0.44 g / 100 g = 0.44(g)×1000(mg))÷((100(g) / 1.0(g / mL)) / 1000(L)) = 4400 mgCl / L (2 significant figures). By performing the same calculation, 1 to 16.5 mass% of the available bromine concentration corresponds to an available chlorine concentration (mgCl / L) of 4400 mgCl / L to 73300 mgCl / L.

[0037] In the bactericidal composition according to this embodiment, the ratio of the equivalent of the "sulfamic acid compound" to the equivalent of the "bromine-based oxidant" is preferably 1.0 or more, more preferably in the range of 1.0 or more and 2.0 or less, and even more preferably in the range of 1.05 or more and 1.5 or less. If the ratio of the equivalent of the "sulfamic acid compound" to the equivalent of the "bromine-based oxidant" is less than 1.0, the bromine concentration may significantly decrease, and if it exceeds 2.0, the production cost may increase.

[0038] In the bactericidal composition according to this embodiment, an alkali may be further added. Examples of the alkali include alkali hydroxides such as sodium hydroxide and potassium hydroxide. From the viewpoints of product stability at low temperatures, etc., sodium hydroxide and potassium hydroxide may be used in combination. Further, the alkali may not be solid and may be used as an aqueous solution.

[0039] In view of cases where bacteria, viruses, etc. are attached to organic substances, etc., it is also effective to add an auxiliary agent to the bactericidal composition in order to enhance the permeability of the stabilized hypobromous acid composition to organic substances, etc. A typical chemical substance of the auxiliary agent is a surfactant. By increasing the permeability of the stabilized hypobromous acid composition, the effects of disinfection, antibacterial, sterilization, and inactivation can be enhanced.

[0040] As the surfactant to be blended, conventionally known substances can be used. Examples of the surfactant include anionic surfactants, nonionic surfactants, cationic surfactants, and amphoteric surfactants, and these can be used alone or in appropriate combinations of two or more.

[0041] Examples of the anionic surfactant include those conventionally used in detergents, etc., and are not particularly limited, and various anionic surfactants can be used. For example, the following anionic surfactants can be mentioned.

[0042] Examples of anionic surfactants include fatty acid salts such as lauric acid and palmitic acid, alkyl ether carboxylic acids, acyl lactates, N-acyl amino acid salts, alkane sulfonates, α-olefin sulfonates, α-sulfo fatty acid methyl ester salts, alkyl diphenyl ether disulfonates, linear alkylbenzene sulfonates, linear alkylnaphthalene sulfonates, alkyl sulfates such as lauryl sulfate, alkyl ether sulfate esters, polyoxyethylene alkyl sulfate esters, polyoxyethylene alkyl allyl sulfate esters, polyoxyethylene alkyl phenyl ether sulfonate alkyl phosphate esters, alkyl sulfosuccinates, and the like.

[0043] Examples of cationic surfactants include quaternary ammonium salts such as N-decyl-N-isononyl-N,N-dimethylammonium chloride, as well as alkyltrimethylammonium salts, dialkyldimethylammonium salts, alkyldimethylbenzylammonium salts, amine salt systems such as N-methylbis(hydroxyethyl)amine fatty acid ester hydrochloride, amine salts such as alkylamine hydrochloride and fatty acid amide amine salts, alkylpyridinium salts, and the like.

[0044] Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers such as polyoxyethylene nonyl phenyl ether, polyoxyethylene alkyl allyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene sorbitan fatty acid esters, alkyl glucosides, polyoxyethylene fatty acid esters, polyoxyethylene castor oil, sucrose fatty acid esters, and polyhydric alcohol fatty acid ester types and polyhydric alcohol alkyl ether types such as sorbitan fatty acid esters, fatty acid alkanolamides, ethylene oxide / propylene oxide adducts of lower / higher alcohols, sucrose fatty acid salts esters, alkanolamides, and the like.

[0045] Examples of amphoteric surfactants include alkylamino fatty acid salts, alkyl betaines, alkyl sulfobetaines, alkyl imidazoline type betaines, and the like.

[0046] The surfactant can be used as one kind or a mixture of two or more kinds, and the addition amount of the surfactant is, for example, in the range of 0.1 to 20% by weight, preferably in the range of 0.1 to 10% by weight, more preferably in the range of 0.1 to 5% by weight with respect to the total amount of the sterilizing composition.

[0047] The sterilizing composition according to this embodiment contains water as the remaining portion of the above components. Examples of water include tap water, pure water, ultrapure water, and the like.

[0048] <Method for producing a sterilizing composition> The sterilizing composition according to this embodiment can be obtained, for example, by mixing a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid in water, and an alkali or a surfactant may be further mixed. The sterilizing composition according to this embodiment can be obtained, for example, by diluting a stabilized hypobromous acid composition obtained by mixing a bromine-based oxidizing agent, a sulfamic acid compound, and, if necessary, an alkali or the like in water with water, adding a strong acid, and adjusting so that the available bromine concentration is in the range of 0.01% or more and 0.25% or less and the pH is in the range of 5.0 to 11.0, or the available bromine concentration is in the range of 0.011% or more and 0.225% or less and the pH is in the range of 5.0 to 10.5.

[0049] As a method for producing a sterilizing composition containing bromine and a sulfamic acid compound, it preferably includes a step of adding bromine to a mixed solution containing water, an alkali, and a sulfamic acid compound and reacting it in an inert gas atmosphere, or a step of adding bromine to a mixed solution containing water, an alkali, and a sulfamic acid compound in an inert gas atmosphere. By adding and reacting in an inert gas atmosphere or adding in an inert gas atmosphere, the bromate ion concentration in the sterilizing composition is lowered.

[0050] The inert gas to be used is not limited, but at least one of nitrogen and argon is preferable from the viewpoint of production and the like, and nitrogen is particularly preferable from the viewpoint of production cost and the like.

[0051] The oxygen concentration in the reactor during the addition of bromine is preferably 6% or less, more preferably 4% or less, still more preferably 2% or less, and particularly preferably 1% or less. When the oxygen concentration in the reactor during the reaction of bromine exceeds 6%, the amount of bromic acid generated in the reaction system may increase.

[0052] The addition rate of bromine is preferably 25% by weight or less based on the total amount of the composition for sterilization, more preferably 1% by weight or more and 20% by weight or less. When the addition rate of bromine exceeds 25% by weight based on the total amount of the composition for sterilization, the amount of bromic acid generated in the reaction system may increase. When it is less than 1% by weight, the antibacterial, disinfection, sterilization effect may be inferior.

[0053] The reaction temperature during the addition of bromine is preferably controlled in the range of 0°C or higher and 25°C or lower, and more preferably controlled in the range of 0°C or higher and 15°C or lower from the viewpoint of production cost and the like. When the reaction temperature during the addition of bromine exceeds 25°C, the amount of bromic acid generated in the reaction system may increase, and when it is less than 0°C, it may freeze.

[0054] <Sterilization method> The sterilization method according to this embodiment is a method of performing sterilization, disinfection, antibacterial, or sterilization of an object to be sterilized using the above-described composition for sterilization. In this specification, "sterilization" in "composition for sterilization", "object to be sterilized", "sterilization method", etc. includes "disinfection" for removing and reducing microorganisms from a certain substance or a limited space, etc., "antibacterial" for suppressing the growth of bacteria on the surface of products, etc., "disinfection" for killing, removing, and reducing pathogenic microorganisms among microorganisms, "sterilization" for killing microorganisms such as bacteria, and also includes "antiviral" for reducing the number of viruses on products, etc., and "mold prevention" for suppressing the growth of mold. Definitions and the like of each term are described in the "Antibacterial Processing Product Guidelines, Antibacterial Product Technology Council" issued by the Ministry of International Trade and Industry, Bureau of Consumer Affairs on May 20, 1999.

[0055] The object to be sterilized is not particularly limited. For example, it can be used for sterilization, antibacterial, disinfection, or sterilization of walls, doors, floors, furniture, kitchen sinks, washing machines, bathrooms, kitchens, dining tables, chairs, office supplies, household items, food containers, fibers, indoor spaces, cleaning factories, inside and outside vehicles, food factories, meat factories, livestock farms, etc. in homes, restaurants, factories, offices, etc.

[0056] For example, the sterilization method according to this embodiment is not particularly limited as long as it can sterilize, antibacterial, disinfect, or sterilize the object to be sterilized. For example, it can be carried out by spraying on the object to be sterilized, wiping and cleaning by impregnating a cloth for the cleaning process, or further diluting the sterilizing composition and immersing equipment and objects.

[0057] In the sterilization method according to this embodiment, the above sterilizing composition may be added to the solution of the object to be sterilized so that the total halogen residue is in the range of, for example, 0.00002% to 0.23% (FAC 0.1 to 50 mg / L) in terms of available bromine concentration. Here, FAC refers to the free chlorine concentration (mg / L).

Examples

[0058] Hereinafter, examples and comparative examples will be given to explain the present invention more specifically and in detail. However, the present invention is not limited to the following examples.

[0059] [Drug A: Preparation 1 of Stabilized Hypobromous Acid Composition] Under a nitrogen atmosphere, liquid bromine: 16.9 wt%, sulfamic acid: 10.7 wt%, sodium hydroxide: 12.9 wt%, potassium hydroxide: 3.94 wt%, and water: the balance were mixed to prepare a stabilized hypobromous acid composition. The pH of the stabilized hypobromous acid composition was 14, and the total chlorine concentration was 7.5 wt%. The total chlorine concentration was the value (mg-Cl2 / L) measured by the total chlorine measurement method (DPD (diethyl-p-phenylenediamine) method) using a multi-parameter water quality analyzer DR / 4000 from HACH. The detailed preparation method of the stabilized hypobromous acid composition is as follows.

[0060] While controlling the flow rate of nitrogen gas with a mass flow controller so that the oxygen concentration in the reaction vessel is maintained at 1%, 1436 g of water and 361 g of sodium hydroxide were added to a 2 L four-necked flask sealed by continuous injection and mixed. Then, 300 g of sulfamic acid was added and mixed. After that, while maintaining cooling so that the temperature of the reaction solution became 0 to 15°C, 473 g of liquid bromine was added, and further 230 g of a 48% potassium hydroxide solution was added to obtain a target stabilized hypobromous acid composition having a sulfamic acid content of 10.7%, a bromine content of 16.9%, and an equivalent ratio of sulfamic acid to the equivalent of bromine of 1.04 by weight ratio with respect to the total amount of the composition. The pH of the resulting solution was 14 as measured by the glass electrode method. The bromine content of the resulting solution was 16.9% as measured by a method of redox titration using sodium thiosulfate after converting bromine to iodine with potassium iodide, which was 100.0% of the theoretical content (16.9%). Also, the oxygen concentration in the reaction vessel during the bromine reaction was measured using an "Oxygen Monitor JKO-02 LJDII" manufactured by Jiko Co., Ltd. Incidentally, the bromic acid concentration was less than 5 mg / kg.

[0061] Incidentally, the pH measurement was performed under the following conditions. Electrode type: Glass electrode type pH meter: IOL-30 type manufactured by Toa DKK Corporation Electrode calibration: Two-point calibration was performed using a neutral phosphate pH (6.86) standard solution (Type 2) and a borate pH (9.18) standard solution (Type 2) manufactured by Kanto Chemical Co., Inc. Measurement temperature: 25°C Measured value: The electrode was immersed in the measurement solution, and the value after stabilization was taken as the measured value, which was the average value of three measurements.

[0062] [Drug B: Preparation of Stabilized Hypobromous Acid Composition 2] 0.4% by weight of water was added to 12% by weight of sodium hypochlorite as Cl₂ 40% by weight and mixed. 18.4% by weight of 40% by weight sodium bromide was added thereto, and after mixing was completed, 40% by weight of a sodium sulfamate solution was further added and mixed. Finally, 1.2% by weight of sodium hydroxide was added and mixed.

[0063] <Examples 1, 2, Comparative Example 1> [Confirmation of storage stability] In a polyethylene sealed container, a chemical agent A (manufactured by Organo Co., Ltd.), which is a stabilized hypobromous acid composition (Examples 1-1 to 1-19, Comparative Examples 1-1 to 1-13), was diluted with water to a predetermined concentration shown in Table 1, and the pH was adjusted with sulfuric acid as a strong acid. Similarly, a chemical agent B (manufactured by Organo Co., Ltd.), which is a stabilized hypobromous acid composition (Examples 2-1 to 2-3), was diluted with water to a predetermined concentration shown in Table 2, and the pH was adjusted with sulfuric acid as a strong acid. The remaining available chlorine amount after storage at 50 °C for 7 days was measured by the total chlorine measurement method (DPD (diethyl-p-phenylenediamine) method), and the available chlorine residual rate (%) was determined. The results are shown in Tables 1 and 2. Also, the relationship between the available bromine concentration (%) and pH described in Table 1 is shown in Figure 1.

[0064]

Table 1

[0065]

Table 2

[0066] When using 16.9% of the stabilized hypobromous acid composition, it was found that when the pH of the diluted chemical agent was 12.5, the stability was 50% or less, and when the bromine concentration was 0.563% or more at pH 11.5, the storage stability was significantly reduced. On the other hand, it was found that when diluting between an available bromine concentration of 0.01% and 0.25% of the chemical agent, especially between 0.011% and 0.225%, and when the pH was in the range of 5 to 11, the stability was significantly improved.

[0067] <Example 3> [Confirmation of bromine gas and chlorine gas generation] A 1.1-liter polyethylene sealed container was filled with 1 L of a solution prepared by diluting Chemical A (manufactured by Organo Co., Ltd.) (Examples 3-1 to 3-6) with dechlorinated Sagamihara well water treated with a filter to a predetermined concentration shown in Table 3. Sulfuric acid was used as a strong acid to adjust the pH to a predetermined value, and the mixture was stirred with a stirrer at 150 rpm. The prepared solution was placed in a 1-L volumetric flask, and after 1 hour in a constant-temperature bath at 30°C, the total chlorine concentration in the solution was measured. Immediately after opening the lid of the volumetric flask, the halogen gas concentration in the headspace was measured using Detector Tube No. 8La of a detector tube type gas measuring instrument (JIS K 0804: Detector Tube Type Gas Measuring Instrument). The results are shown in Table 3.

[0068]

Table 3

[0069] The chemical A using stabilized hypobromous acid was able to suppress the halogen gas odor within the ranges of Examples 3-1 to 3-6.

[0070] When a chemical agent with hypochlorite adjusted to pH 7.5 and 50 mg Cl / L as the available chlorine concentration was measured in the same manner as in Example 3, 0.1 mg Cl / L of halogen gas was generated with hypochlorite.

[0071] Therefore, it was found that stabilized hypobromous acid hardly generates halogen gas, can suppress the generation of unpleasant odors caused by halogen gas during use, and can suppress the adverse effects caused by halogen gas.

[0072] <Example 4> [Confirmation of Bactericidal Effect] Peptone, bonito extract, phosphorus, nitrogen, etc. were added to dechlorinated Sagamihara well water treated with a filter and cultured (hereinafter referred to as "culture solution"). The total number of general bacteria was 7.9×10 4It was CFU / mL.). Stabilized hypobromous acid composition (FAC 250 mg / L, pH 8.5, available bromine concentration 0.056%, manufactured by Organo) 99 mL, 1 mL of the culture solution was added and mixed (hereinafter referred to as "test solution"). After 5 minutes, sodium sulfite was added to inactivate the active ingredient. After a predetermined time, the number of general bacteria (CFU / mL) in the test solution was measured using a Petrifilm AC plate (manufactured by 3M). The results are shown in Table 4.

[0073] Note that the "specimen" in Table 4 refers to a solution obtained by adding 1 mL of the culture solution (7.9×10 4 CFU / mL) to 99 mL of the stabilized hypobromous acid composition (FAC 250 mg / L, available bromine concentration 0.056%, pH 8.5, manufactured by Organo).

[0074]

Table 4

[0075] As shown in Table 4, when 1 mL of the culture solution was added to 99 mL of pure water, it was 8.3×10 2 CFU / mL after 5 minutes, while for the stabilized hypobromous acid composition (FAC 250 mg / L, available bromine concentration 0.056%, pH 8.5, manufactured by Organo), the specimen was 14 CFU / mL after 5 minutes, confirming its bactericidal performance.

[0076] As described above, as in the examples, a bactericidal composition suitable for users including general consumers to perform disinfection, antibacterial, sterilization, or disinfection, less likely to cause rough hands with a pH of 12 or less, and having high storage stability was obtained.

Claims

**Claim 1** A disinfecting composition comprising a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid, wherein the available bromine concentration ranges from 0.01% to 0.25%, and the pH ranges from 5.0 to 11.

0. **Claim 2** A disinfecting composition comprising a bromine-based oxidizing agent, a sulfamic acid compound, and a strong acid, wherein the available bromine concentration ranges from 0.011% to 0.225%, and the pH ranges from 5.0 to 10.

5. **Claim 3** The disinfecting composition according to claim 1 or 2, wherein the strong acid contains at least one strong acid selected from sulfuric acid, hydrochloric acid, and nitric acid. **Claim 4** The disinfecting composition according to any one of claims 1 to 3, wherein the sulfamic acid compound is contained in an amount of 1.0 to 2.0 times the equivalent of the bromine-based oxidizing agent. **Claim 5** The disinfecting composition according to any one of claims 1 to 4, wherein the bromine-based oxidizing agent is bromine. **Claim 6** A disinfection method, characterized in that the disinfecting composition according to any one of claims 1 to 5 is added to an object to be disinfected so that the total halogen residue ranges from 0.00002% to 0.23% of the available bromine concentration.

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