Stericidal composition

Abstract

The present invention provides a bactericidal composition characterized by comprising a weakly acidic, aqueous hypochlorous-acid solution having a pH of 3.0-7.0, which contains, dissolved therein, (A) molecular hypochlorous acid and (B) a nonionic surfactant, the weakly acidic, aqueous hypochlorous-acid solution containing substantially no (C) organic acid or salt thereof and substantially no (D) ionic surfactant.

Description

Technical Field

[0001] The present invention relates to a bactericidal composition. Specifically, it relates to a weakly acidic hypochlorous acid-based bactericidal composition with enhanced rust prevention effect.

Background Art

[0002] The hypochlorous acid in an aqueous solution changes its existence form depending on the pH. Specifically, in the weakly acidic region where the pH is about 3 to 6, most of it exists as molecular hypochlorous acid (HClO), and in the basic region where the pH is 9 or more, the dissociated hypochlorite ion (OCl - ) becomes dominant, and in the strongly acidic region (for example, pH less than 3), the generation of chlorine molecules (Cl2) becomes dominant as the pH decreases. Among these existence forms, molecular hypochlorous acid (HClO) has an extremely high bactericidal effect, and its bactericidal effect is said to be about 80 times that of ionic hypochlorous acid (OCl - ). Weakly acidic hypochlorous acid water containing a large amount of molecular hypochlorous acid having such a high bactericidal effect is used as a disinfectant or bactericide in various fields such as medical, dental, agricultural, and food processing because of its relatively high safety for the human body (see Patent Documents 1, 4, and 5).

[0003] However, chlorine-based disinfectants and bactericides are known to have metal corrosivity, and the same is true for weakly acidic hypochlorous acid. Furthermore, compared with hypochlorite aqueous solutions such as sodium hypochlorite with a high pH, the corrosivity of weakly acidic hypochlorous acid water is higher, and it corrodes metals at a lower concentration and in a shorter time. In response to such problems, bactericidal cleaning agents added with rust preventives composed of organic acids and their salts or bactericidal cleaning agents added with buffering agents have been proposed.

[0004] For example, Patent Document 2 discloses a "bactericide composition containing at least one (A) selected from hypochlorous acid and alkali metal hypochlorites, at least one (B) selected from polyhydric alcohol derivative surfactants, cationic surfactants, and amphoteric surfactants, at least one (C) selected from organic acids and their salts, and a rust inhibitor (D)". It is described that the above rust inhibitor is at least one selected from phosphoric acid, polyphosphoric acid, phosphonic acid, and their salts.

[0005] In addition, Patent Document 3 describes that by adding a buffering agent to a conventionally used hypochlorous acid-based aqueous solution as a bactericide, it becomes possible to effectively suppress the corrosion of metals. Organic acids and salts of organic acids are preferably used as the buffering agent.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0007] The inorganic rust inhibitors such as phosphoric acid and polyphosphoric acid used in Patent Document 2 exhibit a rust prevention effect by depositing a metal salt on the surface of the metal to form a film. However, when such a rust inhibitor is used, there are problems such as partial rusting due to unevenness of the film and the problem that deposits remain on the metal surface even after washing with water. In addition, the organic acid is immediately oxidized by hypochlorous acid, and hypochlorous acid is also reduced, resulting in the loss of bactericidal ability, so it cannot be stored for a long time. Furthermore, even if it is mixed immediately before use, there is a problem that the bactericidal ability decreases during use. Also, the buffering agents preferably used to impart a rust prevention effect in Patent Document 3 are organic acids and salts of organic acids, and have the same problems as described above.

[0008] Therefore, an object of the present invention is to provide a weakly acidic hypochlorous acid aqueous germicidal composition that has low corrosiveness to metals (has a rust prevention effect), does not contain components that reduce the bactericidal ability during storage, and does not contain components that are likely to remain on the surface of the object to be sterilized after use.

Means for Solving the Problems

[0009] The present invention solves the above problems, and the first form of the present invention is a weakly acidic hypochlorous acid aqueous solution having a pH of 3.0 or more and 7.0 or less in which (A) molecular hypochlorous acid and (B) a nonionic surfactant are dissolved, and (C) an organic acid and its salt, and (D) an ionic surfactant are not contained or are substantially not contained. It is a germicidal composition characterized by consisting of a weakly acidic hypochlorous acid aqueous solution.

[0010] In the germicidal composition of the first form of the present invention (hereinafter, also referred to as "the germicidal composition of the present invention"), the nonionic surfactant of (B) is preferably a compound having no carbon-carbon multiple bond in the molecule, and further, at least one selected from the group consisting of polyglycerol fatty acid esters and fluorine-based nonionic surfactants. It is preferably a compound.

[0011] Also, the effective chlorine concentration (mass ppm) contained in the weakly acidic hypochlorous acid aqueous solution is CA is represented by, and the total concentration (ppm by mass) of the (B) nonionic surfactant contained in the weakly acidic hypochlorous acid aqueous solution is C B is represented by, and the total concentration (ppm by mass) of the (C) organic acid and its salt that may be contained in the weakly acidic hypochlorous acid aqueous solution is C C is represented by, and the total concentration (ppm by mass) of the (D) ionic surfactant that may be contained in the weakly acidic hypochlorous acid aqueous solution is C D is represented by, and the total concentration by mass (ppm) of metal ions that may be contained in the weakly acidic hypochlorous acid aqueous solution is C E When represented by, it is preferably satisfied that at least all of the conditions represented by the following formulas (1) to (3) are satisfied, and more preferably all of the conditions represented by the following formulas (1) to (4) are satisfied. 0.5 ≦ C B / C A ≦ 1000 (1) C C / C A < 0.05 (2) C D / C A < 0.05 (3) C E / C A ≦ 0.35 (4).

[0012] A second form of the present invention is a germicidal cleaning agent characterized by containing the germicidal composition of the present invention. The germicidal cleaning agent (hereinafter, also referred to as "the germicidal cleaning agent of the present invention") is preferably a germicidal cleaning agent for cleaning and / or sterilizing an article at least a part of the surface of which is formed of metal.

[0013] The third form of the present invention comprises a first liquid agent consisting of a weakly acidic aqueous hypochlorous acid solution that does not contain the component (B), and a second liquid agent consisting of an aqueous solution of the component (B). It is a two-component kit for preparing the bactericidal composition of the present invention by mixing the first liquid agent and the second liquid agent at a predetermined ratio. When the ratio of the mass of the second liquid agent to the mass of the first liquid agent for mixing at the predetermined ratio is set as the (second liquid agent mass / first liquid agent mass) ratio: X, X is 0.01 or more and 10 or less. The available chlorine concentration in the weakly acidic aqueous hypochlorous acid solution of the first liquid agent is equivalent to the available chlorine concentration obtained by multiplying the available chlorine concentration of the bactericidal composition, which is the object to be prepared, by (1 + X). The concentration of the component (B) in the aqueous solution of the second liquid agent is equivalent to the concentration obtained by multiplying the concentration of the component (B) of the bactericidal composition, which is the object to be prepared, by {(1 + X) / X}. This is the two-component kit characterized by the above.

[0014] The fourth form of the present invention comprises a first liquid agent consisting of a weakly acidic aqueous hypochlorous acid solution that does not contain the component (B), and a second liquid agent consisting of an aqueous solution of the component (B). It is a two-component kit for preparing the bactericidal composition of the present invention by mixing the first liquid agent, the second liquid agent, and water supplied from the outside at a predetermined ratio. When the ratio of the mass of the second liquid agent and the ratio of the mass of water to the mass of the first liquid agent for mixing at the predetermined ratio are set as the (second liquid agent mass / first liquid agent mass) ratio: Y and the (water mass / first liquid agent mass): Z respectively, Y is 0.01 or more and 2 or less, and Z is 2 or more and 50 or less. The available chlorine concentration in the weakly acidic aqueous hypochlorous acid solution of the first liquid agent is equivalent to the available chlorine concentration obtained by multiplying the available chlorine concentration of the bactericidal composition, which is the object to be prepared, by (1 + Y + Z). The concentration of the component (B) in the aqueous solution of the second liquid agent is equivalent to the concentration obtained by multiplying the concentration of the component (B) of the bactericidal composition, which is the object to be prepared, by {(1 + Y + Z) / Y}. This is the two-component kit characterized by the above.

Advantages of the Invention

[0015] Since the bactericidal composition of the present invention uses molecular hypochlorous acid (HClO) as an active ingredient, it has the characteristics of high bactericidal property and relatively high safety for the human body in combination with its pH, similar to the conventional bactericidal composition composed of a weakly acidic aqueous solution of hypochlorous acid. Furthermore, despite being a so-called chlorine-based composition, it has excellent characteristics such as low metal corrosiveness (difficult to rust metals), can be stably stored, and does not generate deposits on the surface of the substance to be sterilized after use.

Mode for Carrying Out the Invention

[0016] The bactericidal composition of the present invention is based on the finding that "a rust prevention effect can be imparted by adding a nonionic surfactant to weakly acidic hypochlorous acid water" obtained through the studies of the present inventors. Based on such findings, further studies were conducted, and it was found that nonionic surfactants not only have a rust prevention effect but also have a specific property of being difficult to decompose molecular hypochlorous acid compared to ionic surfactants. Therefore, by formulating a nonionic surfactant and substantially not containing organic acids, their salts, and ionic surfactants that have been conventionally used as rust preventives, the above effects have been successfully obtained.

[0017] It should be noted that the fact that nonionic surfactants function as rust preventives in a system of weakly acidic aqueous hypochlorous acid solution was first confirmed by the present inventors, and there is no reported example showing this as far as the present inventors know. Although there are several known techniques for adding surfactants to basic aqueous solutions of hypochlorite such as aqueous sodium hypochlorite solution and aqueous solutions made neutral to acidic by adding a buffer thereto, the purpose of adding surfactants in such systems is not to expect a rust prevention effect.

[0018] For example, Patent Document 4 describes "a bactericidal detergent composition for foods, which is obtained by mixing a first agent containing polyglycerol fatty acid ester and a pH regulator, a second agent mainly composed of sodium hypochlorite or ozone, and water, and having a pH of 3 to 7 at the time of mixing", and the above polyglycerol fatty acid ester corresponds to a nonionic surfactant. However, its addition purpose is said to be to enhance the cleaning effect. And as can be seen from the fact that the above bactericidal detergent composition is stored in two parts, since it contains a pH regulator such as phosphoric acid, the storage stability when the two agents are mixed into one liquid is low, and there is also concern about the problem of the deposits.

[0019] Also, Patent Document 5 describes "an antibacterial agent composition containing one or more compounds (C) selected from a specific alcohol compound (A), a surfactant (B), hypochlorous acid, hypochlorite, and a compound that releases hypochlorous acid in water, and having a weight ratio of (A) to (B): (A) / (B) of 2 or less". However, here too, the purpose of blending surfactants, etc. is to exhibit an antibacterial action against fungi adhering to the inside of fibers of textile products, relatively intricate parts of products having a hard surface, etc. In Patent Document 5, the preferable pH of the above antibacterial agent composition is said to be 6 to 14, more preferably 8 to 13.5, and what is specifically used is an aqueous solution of sodium hypochlorite, and in order to make it a weakly acidic hypochlorous acid aqueous solution, it is necessary to add a buffer (it is said that it may be added) to adjust the pH. Therefore, it is considered that the weakly acidic hypochlorous acid aqueous solution system has the same problems as the bactericidal detergent composition of Patent Document 4.

[0020] Furthermore, in the above-mentioned bactericidal agent composition described in Patent Document 2, the surfactant is added for the purpose of preventing a decrease in bactericidal properties due to the addition of a rust preventive agent, and the combined use with a rust preventive agent is a prerequisite.

[0021] As described above, these prior arts do not solve the above problems. In contrast, the bactericidal composition of the present invention has an excellent characteristic of exhibiting a rust prevention effect without substantially containing an organic acid, its salt, and an ionic surfactant. Therefore, for example, it can be suitably used as a bactericidal cleaning agent for cleaning and / or sterilizing an article at least a part of whose surface is formed of metal. Hereinafter, the bactericidal composition of the present invention and the bactericidal cleaning agent of the present invention will be described in more detail centering on each component contained therein. In this specification, the expression of x to y means that it is not less than the numerical value x and not more than the numerical value y, and when only y is provided with a unit, it means that x also has the same unit.

[0022] 1. Regarding the relationship between the pH of weakly acidic hypochlorous acid water and (A) molecular hypochlorous acid and the available chlorine concentration As described above, the existence form of available chlorine in hypochlorous acid water depends on the pH of the aqueous solution. In the weakly acidic hypochlorous acid water constituting the bactericidal composition of the present invention, in order to make most of the available chlorine in the hypochlorous acid water exist as (A) molecular hypochlorous acid and have high bactericidal properties, and from the viewpoint of safety, the pH is set to 3 to 7, preferably 3.5 to 5.5.

[0023] From the viewpoints of the bactericidal effect and low corrosiveness to metal (rust prevention effect), the available chlorine concentration in the bactericidal agent composition of the present invention is preferably 2 ppm to 2000 ppm. When the available chlorine concentration is less than 2 ppm, it tends to be difficult to obtain a sufficient bactericidal effect. When it exceeds 2000 ppm, the bactericidal effect is saturated, and it becomes difficult to obtain the rust prevention effect by (B) a nonionic surfactant. From the viewpoint of bactericidal efficiency, the available chlorine concentration is preferably 10 ppm to 1500 ppm, and more preferably 30 to 1000 ppm.

[0024] Note that the effective chlorine concentration (ppm by mass) means the total chlorine equivalent concentration of chlorine molecules, chlorine compounds with oxidizing power (e.g., molecular hypochlorous acid), and chlorine atom-containing ions with oxidizing power (e.g., ionic hypochlorous acid) dissolved in an aqueous solution. More specifically, it means the concentration obtained by converting the mass-based concentrations of each component to chlorine concentrations based on mass and then summing them up. In an aqueous solution of a weakly acidic metal hypochlorite, in the pH range where almost all of the hypochlorous acid exists in the molecular form, the effective chlorine concentration substantially means the effective chlorine concentration derived from molecular hypochlorous acid. In the present invention, as the effective chlorine concentration, the concentration measured by the absorptiometric method using an iodine reagent is adopted, and it can be measured, for example, using an effective chlorine concentration measurement kit model AQ-202 (Shibata Scientific Co., Ltd.).

[0025] Such weakly acidic hypochlorous acid water can be produced, for example, by an electrolysis method of electrolyzing an aqueous sodium chloride solution, a hydrochloric acid method of adding hydrochloric acid to a basic hypochlorite aqueous solution, or an ion exchange method of treating a raw material aqueous solution composed of a hypochlorite aqueous solution with an ion exchange resin.

[0026] 2. (B) Regarding nonionic surfactants As the (B) nonionic surfactant contained in the weakly acidic hypochlorous acid aqueous solution constituting the bactericidal composition of the present invention, there is no particular limitation as long as it is a surfactant composed of a compound having a hydrophilic part and a lipophilic part in the molecule and not becoming an ion when dissolved in water. For example, polyglycerol fatty acid esters, sorbitan fatty acid esters, sucrose fatty acid esters, fatty acid polyethylene glycols, fatty acid polyoxyethylene sorbitans, polyglycerol alkyl ethers, polyoxyethylene alkyl ethers, fluorine-based nonionic surfactants, etc. can be used. From the viewpoint of the stability of the substance, it is preferable to use polyglycerol fatty acid esters or fluorine-based nonionic surfactants, and among them, it is more preferable to use polyglycerol fatty acid esters because of their easy availability.

[0027] From the viewpoint of the storage stability of the bactericidal composition of the present invention, it is particularly preferable to use a nonionic surfactant that does not contain a carbon-carbon multiple bond in the molecule. Such a nonionic surfactant that does not contain a carbon-carbon multiple bond in the molecule is commercially available. For example, polyglyceryl-10 laurate {C 12 H 24 O2-(C3H6O2) 10}, polyglyceryl-4 lauryl ether {C 12 H 26 O-(C3H6O2)4}, polyoxyethylene (5) lauryl ether, a nonionic surfactant containing a perfluoroalkyl group, etc. can be preferably used.

[0028] The blending amount of the (B) nonionic surfactant contained in the weakly acidic aqueous hypochlorous acid solution may usually be 30 mass ppm to 15 mass% based on the mass of the weakly acidic aqueous hypochlorous acid solution. However, from the viewpoint of the rust prevention effect and the ease of removal by water washing, it is preferably 50 mass ppm to 1.5 mass%, and more preferably 100 mass ppm to 1500 mass ppm.

[0029] Also, from the viewpoint of more effectively exerting the rust prevention effect and the bactericidal effect, when the effective chlorine concentration (mass ppm) contained in the weakly acidic aqueous hypochlorous acid solution is represented by C A and the total concentration (mass ppm) of the (B) nonionic surfactant is represented by C B , the ratio of the two, C B / C A , preferably satisfies the relationship of 0.5 ≦ C B / C A ≦ 1000, and more preferably satisfies the relationship of 0.7 ≦ C B / C A ≦ 900, particularly preferably 1.0 ≦ C B / C A ≦ 800.

[0030] 3. Regarding (C) organic acids and their salts, and (D) ionic surfactants As described above, in conventional bactericidal compositions based on weakly acidic aqueous hypochlorous acid solutions or basic aqueous hypochlorite solutions, (C) organic acids and their salts may be added as rust inhibitors or buffers. Further, in order to enhance detergency, surfactants may be added including (D) anionic surfactants in combination with rust inhibitors or buffers.

[0031] In contrast, in the present invention, in order to obtain the above effects, the weakly acidic aqueous hypochlorous acid solution constituting the bactericidal composition of the present invention needs to substantially not contain (C) organic acids and their salts, and (D) anionic surfactants.

[0032] Here, "substantially not contain" means not containing at all or not adding actively (or consciously), and it is acceptable to be unavoidably contained within a range that does not adversely affect storage stability or the like. The upper limit value of the allowable amount depends on the available chlorine concentration: C A and is usually a concentration that satisfies the following formulas (2) and (3), expressed as a ratio to the available chlorine concentration of each concentration. C C / C A <0.05 (2) C D / C A <0.05 (3) In the above formulas, C C represents the total concentration (mass ppm) of the (C) organic acids and their salts that may be contained in the weakly acidic aqueous hypochlorous acid solution, and C D represents the total concentration (mass ppm) of the (D) anionic surfactant that may be contained in the weakly acidic aqueous hypochlorous acid solution.

[0033] Also, the absolute concentrations of (C) and (D) are each preferably 10 mass ppm or less, more preferably 5 mass ppm or less, and most preferably 1 mass ppm or less, based on the total mass of the weakly acidic aqueous hypochlorous acid solution.

[0034] Examples of the organic acid and its salt (C) that are substantially not contained include citric acid, malonic acid, glutaric acid, adipic acid, sebacic acid, fumaric acid, maleic acid, or its salt, etc.

[0035] In addition, examples of the ionic surfactant (D) that is substantially not contained include, as an anionic surfactant, carboxylic acid type such as aliphatic carboxylate and polyoxyethylene alkyl ether carboxylate, sulfonic acid type such as dialkyl sulfosuccinate and alkane sulfonate, sulfate ester type such as alkyl sulfate and fatty oil sulfate ester salt, phosphate ester type such as alkyl phosphate and polyoxyethylene alkyl ether phosphate type; as a cationic surfactant, alkylamine salt type such as monoalkylamine salt and dialkylamine salt, quaternary ammonium salt type such as alkylbenzalkonium chloride and alkyltrimethylammonium chloride; and as an amphoteric surfactant, alkyl betaine, derivative type of 2-alkylimidazoline, etc.

[0036] 4. Regarding metal ions Generally, molecular hypochlorous acid in an aqueous solution undergoes self-decomposition according to the following formulas: 2HClO → 2HCl + O2 and / or 3HClO → 2HCl + HClO3 and rapid reductive decomposition when in contact with, in particular, organic substances having reducibility, including fungi and the like which are the objects to be sterilized: HClO → HCl + (O) and is known to disappear.

[0037] By the way, when a weakly acidic aqueous solution of hypochlorous acid is produced using a hypochlorite such as sodium hypochlorite as a raw material, metal ions derived from the raw material are often contained in the weakly acidic aqueous solution of hypochlorous acid. For example, when an acid or a buffer is added to an aqueous solution of sodium hypochlorite to make it weakly acidic, not only the metal ions derived from the raw material are contained as they are, but also the metal ions derived from the buffer are contained. Also, when using a cation exchange resin to replace the metal ions derived from the raw material with hydrogen ions (H +Even when produced by an ion exchange method in which metal ions are removed by converting the solution into chlorine, a considerable amount of metal ions may be contained depending on the conditions. It is known that such metal ions rapidly accelerate the autolysis reaction when the concentration of the metal ions exceeds a certain ratio relative to the available chlorine concentration. That is, Patent Document 1 states that for a weakly acidic hypochlorous acid aqueous solution at a liquid temperature of 5 to 40°C, the total concentration (ppm by mass) of metal ions contained therein is C E When expressed as a concentration of available chlorine, C A Ratio to: C E / C A It is described that when the C is 0.35 or more, the self-decomposition reaction proceeds rapidly. Therefore, the weakly acidic hypochlorous acid aqueous solution constituting the disinfectant composition of the present invention is E / C A It is preferable that the condition represented by the following formula (4) is satisfied, and it is particularly preferable that the condition represented by the following formula (4') is satisfied. C E / C A ≦0.35 (4) C E / C A ≦0.25 (4´).

[0038] To obtain a weakly acidic hypochlorous acid aqueous solution that satisfies the above conditions, for example, a method such as that described in Patent Document 1 can be employed. That is, the method includes an ion exchange step in which a raw material aqueous solution consisting of an aqueous solution of a metal salt of hypochlorous acid is mixed with a weakly acidic ion exchange resin to perform ion exchange between metal ions and hydrogen ions, thereby generating molecular hypochlorous acid dissolved in the mixed solution; and a separation step in which the weakly acidic ion exchange resin is separated from the mixed solution after the ion exchange step to obtain a target aqueous solution consisting of an aqueous solution in which molecular hypochlorous acid is dissolved; and in the ion exchange step, the ratio of the amounts of the raw material aqueous solution and the weakly acidic ion exchange resin to be mixed is adjusted to the total ion exchange equivalent (E IE ) and the total chemical equivalents of metal ions in the raw solution (E MI ) ratio: (E MI / E IEThe mixing ratio is set such that [[ID=]] is 0.05 or more and 0.5 or less, the liquid temperature during mixing is 5°C or more and 40°C or less, and the mixing time is 10 minutes or more and 120 minutes or less.

[0039] Note that the weakly acidic hypochlorous acid aqueous solution constituting the bactericidal composition of the present invention may contain, if necessary, metal ions exhibiting antibacterial properties such as silver ions, zinc ions, and copper ions, or foaming properties composed of carbonates, hydrogen carbonates, and double salts of hydrogen carbonate and carbonate serving as metal ion sources. Even in such a case, the C E / C A preferably satisfies the conditions represented by the formula (4), particularly the formula (4´).

[0040] 5. Regarding the preparation method and use of the bactericidal composition of the present invention For the bactericidal composition of the present invention, all components may be mixed in advance so as to have a predetermined concentration to prepare the weakly acidic hypochlorous acid aqueous solution, which may be used as the bactericidal composition as it is. Alternatively, a weakly acidic hypochlorous acid aqueous solution having a concentration several to several tens of times higher than the concentration at the time of use may be prepared, diluted with water to obtain a weakly acidic hypochlorous acid aqueous solution having a predetermined concentration, which may be used as the bactericidal composition of the present invention. However, in the latter case, if the concentration of each component is too high, the storage stability during long-term storage tends to decrease. Therefore, when diluting and using, it is preferably a two-liquid type kit shown in the following (1) or (2) for long-term storage (which is also a kit for preparing the bactericidal cleaning agent of the present invention). The bactericidal composition of the present invention having a predetermined concentration that can be used in a relatively short period is prepared each time by mixing the two liquids {(1)} or adding a predetermined amount of water for further dilution after mixing the two liquids {(2)}.

[0041] (1) A two-liquid type kit for preparing the bactericidal composition of the present invention, comprising a first liquid agent composed of a weakly acidic hypochlorous acid aqueous solution not containing the component (B) and a second liquid agent composed of an aqueous solution of the component (B), and preparing the bactericidal composition of the present invention by mixing the first liquid agent and the second liquid agent at a predetermined ratio. When the ratio of the mass of the second liquid agent to the mass of the first liquid agent that is mixed at the predetermined ratio is set as the (second liquid agent mass / first liquid agent mass) ratio: X, X is 0.01 to 10, preferably 0.02 to 10, more preferably 0.5 to 8. The available chlorine concentration in the weakly acidic hypochlorous acid aqueous solution of the first liquid agent is equivalent to the available chlorine concentration obtained by multiplying the available chlorine concentration of the bactericidal composition which is the preparation target by (1 + X). The concentration of the component (B) in the aqueous solution of the second liquid agent is equivalent to the concentration obtained by multiplying the concentration of the component (B) of the bactericidal composition which is the preparation target by {(1 + X) / X}. The two-component kit is characterized by the above.

[0042] (2) A two-component kit for preparing the bactericidal composition of the present invention by mixing a first liquid agent composed of a weakly acidic hypochlorous acid aqueous solution that does not contain the component (B), a second liquid agent composed of an aqueous solution of the component (B), and water supplied from the outside at a predetermined ratio, When the mass ratios of the mass of the second liquid agent and the mass of the water to the mass of the first liquid agent that are mixed at the predetermined ratio are set as the (second liquid agent mass / first liquid agent mass) ratio: Y and (water mass / first liquid agent mass): Z respectively, Y is 0.01 to 2, preferably 0.02 to 2, more preferably 0.5 to 1.5 and Z is 2 to 50, preferably 2 to 40, more preferably 2 to 35. The available chlorine concentration in the weakly acidic hypochlorous acid aqueous solution of the first liquid agent is equivalent to the available chlorine concentration obtained by multiplying the available chlorine concentration of the bactericidal composition which is the preparation target by (1 + Y + Z). The concentration of the component (B) in the aqueous solution of the second liquid agent is equivalent to the concentration obtained by multiplying the concentration of the component (B) of the bactericidal composition which is the preparation target by {(1 + Y + Z) / Y}. The two-component kit is characterized by the above.

[0043] Here, "equal concentration" means that the concentration is the same as the concentration to be calculated, or within ±20%, preferably within ±10% of that concentration. Also, the available chlorine concentration in the bactericidal composition as the preparation target is preferably 30 to 1000 ppm, particularly preferably 50 to 500 ppm, and the concentration of the component (B) is preferably 50 mass ppm to 1.5 mass%, particularly preferably 100 to 1500 mass ppm. Furthermore, it goes without saying that neither of the liquid agents in the kit of (1) and (2) substantially contains (C) organic acids and their salts, and (D) ionic surfactants.

[0044] The bactericidal composition of the present invention uses molecular hypochlorous acid as an active ingredient, and since it is not basic or strongly acidic which requires attention in handling, it has a high bactericidal effect, is relatively safe, and is easy to handle. Therefore, it is useful for sterilization in a wide range of fields such as hospitals, food processing factories, educational facilities, and nursing facilities.

[0045] Furthermore, the bactericidal composition of the present invention has excellent characteristics not found in conventional weakly acidic hypochlorous acid aqueous solution-based bactericidal compositions, such as not corroding metals (not generating rust on metals) and being difficult for residues to remain after water washing. Therefore, in addition to articles made of plastic, rubber, tile, brick, cement, glass, wood, cloth, non-woven fabric, vinyl, leather, ceramic, etc., it can also be used for articles containing metals, particularly articles containing easily rusted steel, cobalt chromium, silver, zinc, brass, etc.

[0046] The bactericidal cleaner of the present invention is characterized by containing the bactericidal composition of the present invention. Here, the bactericidal cleaner means a cleaner for removing dirt attached to an article and / or a bactericide for killing or removing (sterilizing or disinfecting) microorganisms such as bacteria attached to the article. The bactericidal cleaner of the present invention can be suitably used as a bactericidal cleaner for cleaning and / or sterilizing an article at least a part of the surface of which is formed of metal, particularly easily rusted steel, cobalt chromium, silver, zinc, brass, etc.

[0047] The germicidal detergent of the present invention may consist only of the germicide composition of the present invention, but various additives and the like can be included as long as the effects are not impaired or in a blending method. For example, in order to improve the adhesion to the object to be sterilized, it is also possible to add a thickener to make it gel-like or paste-like. As the thickener, it is preferable to use inorganic particles, and it is more preferable to use inorganic particles having an average primary particle diameter of 5 nm or more and 100 nm or less.

[0048] The method of using the germicidal composition of the present invention and the germicidal detergent of the present invention is not particularly limited. For example, the germicidal composition may be brought into contact with the object to be used by spraying, coating, dipping, etc. Specifically, for example, after spraying and wiping using a sprayer such as a trigger to a place to be sterilized, a method of washing with water after immersing the object to be sterilized in the germicidal composition, a method of spraying the germicidal composition into a mist by an ultrasonic nebulizer and spraying it into the space, a method of rubbing the object by impregnating the germicidal composition into a material such as a cloth or non-woven fabric that can be impregnated, a method of applying the germicidal composition to the object to be sterilized using a brush or syringe and then washing with water or wiping, etc. can be mentioned. Further, in the method of immersing the object to be sterilized in the germicidal composition, it is also possible to use ultrasonic waves to enhance the cleaning effect. Furthermore, this germicidal composition may be used as a cleaning liquid when using a wash dispenser used for cleaning and sterilizing medical instruments.

Examples

[0049] Hereinafter, in order to specifically explain the present invention, examples and comparative examples will be given for explanation, but the present invention is not limited thereto.

[0050] First, the nonionic surfactant used in the examples and comparative examples, and the raw materials used for producing weakly acidic hypochlorous acid water; the method for preparing weakly acidic hypochlorous acid water; and the evaluation method for weakly acidic hypochlorous acid water; will be described.

[0051] (1) Raw materials, etc. [Nonionic surfactant without multiple bonds] · Polyglyceryl-10 laurate (manufactured by Daicel Corporation, hereinafter abbreviated as "PGLE"). · Polyglyceryl-4 lauryl ether (manufactured by Daicel Corporation, hereinafter abbreviated as "PGLAL"). · Polyoxyethylene (5) lauryl ether (manufactured by Nikko Chemicals Co., Ltd., hereinafter abbreviated as "POELE"). · Perfluoroalkyl group-containing nonionic surfactant: Product name Surflon S-242 (manufactured by AGC Seimi Chemical Co., Ltd., hereinafter abbreviated as "S-242").

[0052] [Nonionic surfactant containing multiple bonds] · Polyoxyethylene (10) oleyl ether (manufactured by Nikko Chemicals Co., Ltd., hereinafter abbreviated as "POEOE").

[0053] [Anionic surfactant] · Sodium α-olefin sulfonate: Product name K Ribolan PJ-400CJ (manufactured by Lion Specialty Chemicals Co., Ltd., hereinafter abbreviated as "PJ-400").

[0054] [Organic acid salt] · Trisodium citrate (manufactured by Fujifilm Wako Pure Chemical Corporation, hereinafter abbreviated as "STC").

[0055] [Raw materials used for the production of high-concentration weakly acidic hypochlorous acid water] · Aqueous NaClO solution with an available chlorine concentration of 12.0% by mass (Neo Rakus Super: Supplier Shimada Shoten). · Weakly acidic ion exchange resin Amberlite IRC-76 (H + form, manufactured by Organo Corporation, hereinafter abbreviated as "IRC76").

[0056] (2) Method for preparing weakly acidic hypochlorous acid water The 12.0 mass% aqueous NaClO solution was diluted with ion-exchanged water to adjust the available chlorine concentration to 11000 ppm, and 2400 ml of the raw material aqueous solution was prepared. Next, 200 ml of the weakly acidic ion-exchange resin IRC76 was weighed, the entire amount of the raw material aqueous solution was added, and stirring was carried out for 20 minutes using a fluororesin stirring blade so that the weakly acidic ion-exchange resin was uniformly dispersed. During stirring, the pH of the mixed solution was monitored, and stirring was stopped when the pH decreased and reached 6.3. After the stirring was completed, it was allowed to stand until the resin settled, and the hypochlorous acid aqueous solution, which was the supernatant, was collected in a polyethylene container through a #200 filter cloth so that the resin would not get in. The solution was left at room temperature for 3 hours until the pH reached 4.8. The available chlorine concentration after standing was 9000 ppm.

[0057] (3) Evaluation method (3-1) Measurement of available chlorine concentration (manufacture) A part of the sodium hypochlorite aqueous solution and the weakly acidic hypochlorous acid water was used as a sample solution. The sample solution was diluted with ion-exchanged water at the following dilution ratios according to the available chlorine concentration of the raw material solution to prepare a measurement sample, and the available chlorine concentration after dilution was measured using an available chlorine concentration measurement kit AQ-202 type (Shibata Scientific Co., Ltd.). The available chlorine concentration of the sample solution was determined from the measurement results and the dilution ratio. · Available chlorine concentration of the raw material solution is 300 ppm or less: Without dilution · Available chlorine concentration of the raw material solution is 301 - 900 ppm: Dilution ratio 3 times · Available chlorine concentration of the raw material solution is 901 - 3000 ppm: Dilution ratio 10 times · Available chlorine concentration of the raw material solution is 3001 - 15000 ppm: Dilution ratio 50 times

[0058] (3-2) pH measurement The pH of the weakly acidic hypochlorous acid water and the disinfectant composition was measured using a pH meter F-55 type (HORIBA, Ltd.).

[0059] (3-3) Measurement of total metal ion concentration (mass ppm) and C E / C A Calculation method of value Weak acidic hypochlorous acid water and the disinfectant composition were diluted with ion-exchanged water so that the available chlorine concentration became 20 ppm to prepare a measurement sample. Measurement was performed using ICP emission spectrometer iCAP6500DUO (manufactured by Thermo Fisher Scientific), and C E / C A value was calculated from the following formula (5). C E / C A = Measured value (ppm) / 20 (5)

[0060] (3 - 4) Evaluation of rust 40 ml of the sample solution was put into a 50 cc glass bottle, and a dental steel bar ("Elastil bar (manufactured by Matsuura)") was immersed in the solution. After a predetermined time, the presence or absence of rust was visually confirmed. ○: Rust was not confirmed. △: Slight rust was confirmed. ×: Obvious rust was confirmed.

[0061] (3 - 5) Evaluation of storage stability 40 ml of the sample solution was put into a 50 cc glass bottle, stored at room temperature (10 - 23 °C) for a predetermined time, and then the available chlorine concentration and pH were measured to confirm the change from the initial value. The available chlorine concentration measurement during the storage stability evaluation was performed using a water quality test strip (Nissan Aqua Check HC).

[0062] (3 - 6) Cleaning evaluation 40 ml of the sample solution was put into a 50 cc glass bottle, a cleaning evaluation indicator TOSI (manufactured by PEREG GmbH) was immersed, and left for 5 minutes. After taking out the indicator, destroying the plastic part of the indicator, taking out the measurement part, it was lightly washed with water. A residual protein detection solution (manufactured by Saraya Co., Ltd.) was applied and left for 30 seconds. After lightly washing with water, the cleaning condition was visually evaluated.

[0063] (3 - 7) Sterilization evaluation Tokuyama A-1α (manufactured by Tokuyama Dental Corporation) was used to prepare an alginate plate measuring 19 mm in length × 57 mm in width × 3 mm in thickness. After applying 100 μl of saliva to one side of the alginate plate and gently rinsing with water, the alginate plate was immersed in 200 ml of the sample solution. After immersion for 30 seconds, the alginate plate was taken out, and the saliva-treated surface of the alginate plate was gently pressed against the brain heart infusion medium to bring the saliva-treated surface into contact with the entire medium. The alginate plate was removed, and after culturing in an incubator at 37°C for one week, the presence or absence of bacteria (colonies) was visually confirmed.

[0064] Example 1 18.7 ml of ion-exchanged water was added to 1.3 ml of weakly acidic hypochlorous acid water with an available chlorine concentration of 9000 ppm prepared in (2) above, and the mixture was stirred with a stirrer for 1 minute. In another container, 0.4 g of the surfactant PGLE and 19.6 g of ion-exchanged water were weighed out and stirred with a stirrer for 10 minutes until uniform. Immediately before each evaluation, 20 g each of the prepared aqueous solutions were placed in 50 ml screw-cap tubes and mixed by hand shaking for 10 seconds to obtain a bactericidal composition. The total metal ion concentration (mass ppm) of the obtained bactericidal composition was measured, and the C E / C A value was determined. The bactericidal composition and the C E / C A values are shown in Table 1. Using a separately prepared bactericidal composition in the same manner, an evaluation of rust and a storage stability evaluation were performed on a dental steel bar. The evaluation results are shown in Tables 2 and 3.

[0065] Examples 2 to 5, Comparative Examples 1 to 3 A bactericidal composition was prepared in the same procedure as in Example 1, except that the type of surfactant used was changed as shown in Table 1, and an evaluation of rust and a storage stability evaluation were performed. The evaluation results are shown in Tables 2 and 3.

[0066]

Table 1

[0067]

Table 2

[0068]

Table 3

[0069] Examples 6 to 13, Comparative Examples 4 to 7 The amount of ion-exchanged water for diluting denture cleaner and the amount of surfactant were changed, and a disinfectant composition was prepared in the same procedure as in Example 1, and rust evaluation was performed. Further, in Examples 6, 7, 8, and 11, cleaning and disinfection evaluation were performed.

[0070] The evaluation results are shown in Tables 4 and 5.

[0071]

Table 4

[0072]

Table 5

[0073] Weak acidic hypochlorous acid water with an available chlorine concentration of 300 ppm (Comparative Example 1) showed obvious rust after 5 minutes, but in the disinfectant composition with an available chlorine concentration of 300 ppm, no rust was confirmed even after 1 day in Examples 1 to 3. Regarding Example 4, slight rust was confirmed after 24 hours, and in Example 5, it was only to the extent that slight rust was confirmed after 3 hours. Further, in Examples 1 to 4, no change was confirmed in the available chlorine concentration and pH after storage at room temperature for 1 day, but in Example 5 using a surfactant containing a carbon-carbon multiple bond in the molecule, the available chlorine concentration gradually began to decrease immediately after production, but it maintained 50 ppm until 30 minutes later.

[0074] Similarly, in Examples 6 to 13 and Comparative Examples 4 to 6, regardless of the available chlorine concentration and surfactant concentration, a rust prevention effect was confirmed by adding a surfactant.

[0075] In Examples 6, 7, 8, and 11, it was confirmed that the cleaning effect was high compared to the cleaning with sterilized water in Comparative Example 7. Further, in the sterilization evaluation, no colonies were formed in Examples 6, 7, 8, and 11, and a sterilization effect was confirmed.

[0076] From the above results, it was confirmed that the rust prevention effect by the surfactant was obtained, and it was shown that the storage stability was improved by not containing a compound that is easily oxidized, for example, an organic acid.

Claims

Claim 1: A germicidal cleaner for cleaning and / or sterilizing an article having at least a part of its surface formed of metal, comprising: (A) molecular hypochlorous acid and (B) a weakly acidic hypochlorous acid aqueous solution with a pH of 3.0 or more and 7.0 or less in which at least one nonionic surfactant selected from the group consisting of polyglycerin fatty acid esters and fluorine-based nonionic surfactants is dissolved, (C) an organic acid and its salts, and (D) an ionic surfactant, each having a content of 10 mass ppm or less based on the total mass of the weakly acidic hypochlorous acid aqueous solution, and a germicidal composition comprising the weakly acidic hypochlorous acid aqueous solution. Claim 2 Let C represent the available chlorine concentration (ppm by mass) contained in the weakly acidic aqueous hypochlorous acid solution Ａ and Let C be the total concentration (ppm by mass) of the (B) nonionic surfactant contained in the weakly acidic hypochlorous acid aqueous solution. Ｂ It is represented by Let C represent the total concentration (ppm by mass) of the organic acid (C) and its salt that may be contained in the weakly acidic hypochlorous acid aqueous solution. Ｃ It is represented by When the total concentration (ppm by mass) of the (D) ionic surfactant that may be contained in the weakly acidic hypochlorous acid aqueous solution is represented by C Ｄ then The following formulas (1) to (3) 0.5 ≤ C Ｂ / C Ａ ≤ 1000 (1) C Ｃ / C Ａ < 0.05 (2) C Ｄ / C Ａ <0.05 (3) The germicidal cleaner according to claim 1, which satisfies all of the conditions represented by

3. When the total concentration mass (ppm) of metal ions that can be contained in the weakly acidic aqueous hypochlorous acid solution is represented by C Ｅ the germicidal detergent according to claim 2, wherein C Ｅ / C Ａ is 0.35 or less. Claim 4 A two-component kit for preparing the germicidal composition according to claim 1, comprising a first liquid agent composed of a weakly acidic hypochlorous acid aqueous solution not containing the component (B) and a second liquid agent composed of an aqueous solution of the component (B), wherein the germicidal composition according to claim 1 is prepared by mixing the first liquid agent and the second liquid agent at a predetermined ratio. When the ratio of the mass of the second liquid agent to the mass of the first liquid agent for mixing at the predetermined ratio is (second liquid agent mass / first liquid agent mass) ratio: X, X is 0.01 or more and 10 or less. The effective chlorine concentration in the weakly acidic hypochlorous acid aqueous solution of the first liquid agent is equivalent to the effective chlorine concentration of the germicidal composition, which is the preparation target, multiplied by (1 + X). The concentration of the component (B) in the aqueous solution of the second liquid agent is equivalent to the concentration of the component (B) in the germicidal composition, which is the preparation target, multiplied by {(1 + X) / X}. The two-component kit is characterized by the above. Claim 5 A two-component kit for preparing the germicidal composition according to claim 1, comprising a first liquid agent composed of a weakly acidic hypochlorous acid aqueous solution not containing the component (B) and a second liquid agent composed of an aqueous solution of the component (B), wherein the germicidal composition according to claim 1 is prepared by mixing the first liquid agent, the second liquid agent, and water supplied from the outside at a predetermined ratio. When the ratio of the mass of the second liquid agent and the mass of water to the mass of the first liquid agent for mixing at the predetermined ratio are (second liquid agent mass / first liquid agent mass) ratio: Y and (water mass / first liquid agent mass): Z, respectively, Y is 0.01 or more and 2 or less, and Z is 2 or more and 50 or less. ​ ​ The available chlorine concentration in the weakly acidic aqueous hypochlorous acid solution of the first liquid agent is equivalent to the available chlorine concentration obtained by multiplying the available chlorine concentration of the bactericidal composition, which is the object of preparation, by (1 + Y + Z). The concentration of the component (B) in the aqueous solution of the second liquid agent is equivalent to the concentration obtained by multiplying the concentration of the component (B) of the bactericidal composition, which is the object of preparation, by {(1 + Y + Z) / Y}. The two-component kit is characterized by this.

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