Liquid detergent composition for hard surfaces

Abstract

To provide a liquid detergent composition for hard surfaces that exhibits excellent foam stability and excellent rinsability when used by foaming an undiluted composition or a diluted solution thereof.SOLUTION: A liquid detergent composition for hard surfaces containing (a) an alkylbenzene sulfonate having an alkyl group with 10 or more and 18 or less carbon atoms, (b) a polymer copolymer containing a structural unit derived from a carboxylic acid or a salt thereof having a reactive unsaturated group with 3 or more and 6 or less carbon atoms (b-1) and a structural unit derived from a polymerizable olefin having 4 or more and 12 or less carbon atoms and optionally having an aryl group (b-2), (c) an oxidizing halogen acid or a salt thereof, (d) an alkali metal hydroxide, and water, wherein a mass ratio [(a) / (b)] of a content of component (a) to a content of component (b) is 0.5 or more and 8 or less, and pH at 25°C is 12 or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a liquid detergent composition for hard surfaces and a method for cleaning hard surfaces, particularly to a liquid detergent composition for cleaning food-stained hard surfaces. In particular, the present invention relates to a liquid detergent composition for hard surfaces that is foamed and brought into contact with floors, walls, cooking equipment, cooking appliances, or cooking utensils in the backrooms of supermarkets where food is prepared or processed, or in the kitchens of restaurants, and a method for cleaning hard surfaces using the liquid detergent composition for hard surfaces. [Background technology]

[0002] In the backroom of supermarkets, purchased meat and fish are prepared, then cut into appropriate sizes and shapes and packaged on trays. Fresh food is also prepared for serving as prepared meals or boxed lunches. Similar tasks are also performed in the kitchens of restaurants and independently owned eateries. Because these places process food and provide cooked products that are consumed directly by consumers, they must regularly clean not only the equipment and facilities used for pre-processing and cooking, but also the floors and walls of the kitchen and galley to maintain sanitary conditions. Galleys and kitchens are generally designed to allow direct drainage of wastewater from the floor. During cleaning, cleaning agents are applied to the floors, walls, counters, and even some of the utensils in the cooking area, leaving them for a while before rinsing with water using a hose or bucket. While some cooking equipment is modularized, independent installations often have gaps or are installed in different locations, necessitating efficient cleaning methods. To address this issue, foam cleaning, which involves foaming a cleaning agent using a spray device or similar to bring the foamed detergent into contact with the object to be cleaned, has been adopted (e.g., Patent Documents 1 to 5). In addition, the cleaning solution is often a detergent diluted with tap water, and the dilution rate may be changed depending on the object to be cleaned.

[0003] Foaming cleaning applies the cleaning agent in foam form, which allows it to stay on the object for a longer time, improving the cleaning and sterilizing effect. In addition, contact cleaning with foam allows you to visually check the spraying status of the cleaning agent, making it easy to identify the area to be treated and preventing unnecessary spraying of the cleaning agent.

[0004] Patent Documents 1 and 2 disclose cleaning compositions for food factories that contain an aromatic compound having a sulfate group and a sulfonate group, a polyoxyalkylene alkyl ether sulfate ester salt, a hypochlorite, and an alkaline agent, and describe a polymer dispersant as an optional component. Patent Document 3 discloses a cleaning composition containing two types of polycarboxylate polymers, and describes the use of a polyacrylic acid monomer in combination with a copolymer of maleic acid, maleic anhydride, and vinyl ester, and a surfactant. In the examples, the document describes a cleaning composition containing heptyl-nonyl sulfonate, coconut fatty acid, C12-13 branched sulfate, hypochlorite, caustic alkali, and a copolymer of acrylic acid and vinyl ester known as Polygel DR (product name). Patent Document 4 discloses a cleaning composition containing a halogen bleach, sulfamine, and a polycarboxylate polymer, and its examples include a cleaning composition containing two types of alkyl sulfate ester salts (C8 and C12-14), a copolymer of acrylic acid and a fatty acid acrylate, caustic alkali, sodium hypochlorite, and a fatty acid. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2023-81571 [Patent Document 2] Japanese Patent Publication No. 2023-81572 [Patent Document 3] Special Publication No. 2002-526641 [Patent Document 4] Special Publication No. 2000-504063 Summary of the Invention [Problem to be solved by the invention]

[0006] Hypochlorite-containing cleaning compositions used in supermarket back-of-house cooking facilities and kitchens are typically diluted from concentrate to form a foam. In food processing plants, cleaning applications and treatment areas are often large, so cleaning compositions are designed for high dilution rates. While the undiluted solution may be used in supermarket back-of-house cooking areas and restaurant kitchens, the degree of dilution must be considered. For example, for widespread application, the composition is diluted 20 to 60 times and foamed. For severe soiling or to achieve sufficient virucidal or sterilizing properties, the composition is diluted about 10 times from concentrate and foamed. To achieve excellent cleaning and sterilizing properties on hard surfaces, it is desirable for the cleaning composition or its water dilution to have excellent foam retention and be less likely to run off the hard surface after foaming and applying it to the surface. Furthermore, when rinsing, it is preferable for the foam to break and immediately flow away when sprayed with water from a hose or the like, without re-foaming due to the force of the water. The present invention provides a liquid detergent composition for hard surfaces, which has excellent foam retention when used by foaming an undiluted solution of the composition or a diluted solution thereof, and which has excellent rinsing properties, in that the foam is easily broken and does not easily re-foam due to further dilution during rinsing, and a method for cleaning hard surfaces. [Means for solving the problem]

[0007] The present invention relates to a composition containing: (a) 1% by mass or more and 8% by mass or less of an alkylbenzenesulfonate having an alkyl group having 10 to 18 carbon atoms; (b) a polymer copolymer containing a structural unit derived from a carboxylic acid or a salt thereof (b-1) having a reactive unsaturated group having from 3 to 6 carbon atoms and a structural unit derived from a polymerizable olefin (b-2) having from 4 to 12 carbon atoms, which may have an aryl group; (c) an oxidizing halogen acid or its salt in an amount of 1% by mass or more and 10% by mass or less; (d) alkali metal hydroxides, and water, wherein the mass ratio of the content of the component (a) to the content of the component (b), [(a) / (b)], is 0.5 or more and 8 or less, and the pH at 25°C is 12 or more.

[0008] The present invention also relates to a method for cleaning a hard surface, which comprises contacting the above-mentioned liquid detergent composition for hard surfaces or a diluted solution obtained by diluting the composition with hard water with the hard surface. [Effects of the Invention]

[0009] According to the present invention, there are provided a liquid detergent composition for hard surfaces, which has excellent foam retention when the undiluted solution of the composition or a diluted solution thereof is foamed and used, and which has excellent rinsing properties, in that the foam is easily broken and does not easily re-foam as the dilution progresses during rinsing, and a method for cleaning hard surfaces. DETAILED DESCRIPTION OF THE INVENTION

[0010] The reason why the liquid cleaning composition for hard surfaces of the present invention has excellent foam retention when used by foaming the undiluted solution of the composition or its diluted solution, and furthermore, the dilution progresses during rinsing, making the foam more likely to break and less likely to re-foam, is not entirely clear, but is presumed to be as follows. Foaming can be achieved by using specific surfactants, but after the foam is applied to the target surface, it must have good foam retention. Furthermore, rinsability requires that the foam breaks down and flows easily when water is sprayed on it. While the foam disappears, physical factors such as showering can cause re-foaming. To prevent this, we investigated whether forming an association between the anionic surfactant (the main base) and something else could constrain the anionic surfactant, increasing the critical micelle concentration (CMC) and the minimum foaming concentration, thereby preventing foaming. We discovered an amphiphilic polymer containing hydrophilic and lipophilic monomer units that would likely adsorb via hydrophobic interactions. The association strengthens the foam film, improving foam retention. The formation of the association reduces the amount of surfactant used at the foam interface, increasing the minimum foaming concentration and suppressing re-foaming. In other words, it is presumed that the liquid detergent composition for hard surfaces of the present invention, which contains the alkylbenzene sulfonate salt of component (a) and the polymer copolymer of component (b), is able to achieve both foam retention during use and foam breaking during rinsing. The liquid detergent composition for hard surfaces and the cleaning method of the present invention are not limited to the above-mentioned mechanism of action.

[0011] <Liquid cleaning composition for hard surfaces> The liquid detergent composition for hard surfaces of the present invention contains (a) an alkylbenzenesulfonate salt having an alkyl group containing from 10 to 18 carbon atoms (hereinafter referred to as component (a)), (b) a polymer copolymer containing a structural unit derived from a carboxylic acid or a salt thereof (b-1) having a reactive unsaturated group containing from 3 to 6 carbon atoms and a structural unit derived from a polymerizable olefin (b-2) having from 4 to 12 carbon atoms and optionally having an aryl group (hereinafter referred to as component (b)), (c) an oxidizing halogen acid or a salt thereof (hereinafter referred to as component (c)), (d) an alkali metal hydroxide (hereinafter referred to as component (d)), and water, wherein the mass ratio [(a) / (b)] of the content of component (a) to the content of component (b) is from 0.5 to 8, and the pH at 25°C is 12 or higher.

[0012] <Component (a)> Component (a) is an alkylbenzenesulfonate having an alkyl group having from 10 to 18 carbon atoms. Component (a) may be an alkylbenzenesulfonate having a linear alkyl group having from 10 to 18 carbon atoms, in which the carbon atom of the alkyl group bonded to the benzene ring is the second carbon atom. One or more types of component (a) can be used. From the viewpoint of further enhancing solution stability, the number of carbon atoms in the alkyl group of component (a) is preferably 12 or more, and preferably 16 or less, more preferably 14 or less. The alkyl group of component (a) is even more preferably a linear alkyl group having 12 carbon atoms. Furthermore, the bonding position of the sulfonic acid group on the benzene ring is preferably in the para position relative to the bonding position of the alkyl group. Furthermore, from the viewpoint of further reducing substrate damage to metallic hard surfaces, the carbon atom of the linear alkyl group bonded to the benzene ring is preferably a secondary carbon atom. The salt of component (a) in the composition is preferably an alkali metal salt, more preferably a sodium or potassium salt, and even more preferably a sodium salt, although after dilution with hard water it may be a calcium or magnesium salt. Component (a) may be used in the form of an acid and then neutralized in the composition.

[0013] <(b) Component> Component (b) is a polymer containing a structural unit derived from a carboxylic acid or salt thereof (b-1) having a reactive unsaturated group having from 3 to 6 carbon atoms and a structural unit derived from a polymerizable olefin (b-2) having from 4 to 12 carbon atoms and optionally having an aryl group. Component (b) is a polymer containing a structural unit derived from (b-1) and a structural unit derived from (b-2), and the ratio of the structural units derived from (b-1) to the structural units derived from (b-2) constituting the polymer [(b-1) / (b-2)] in terms of the molar ratio of the monomers is from 10 / 90 to 90 / 10. Component (b) is a preferred component from the viewpoint of further improving rinsing properties. One or more types of component (b) can be used. Hereinafter, a carboxylic acid or a salt thereof having a reactive unsaturated group having 3 to 6 carbon atoms will be referred to as component (b-1), and a polymerizable olefin having 4 to 12 carbon atoms which may have an aryl group will be referred to as component (b-2).

[0014] <(b-1) component> Examples of the component (b-1) include maleic acid, maleic anhydride, acrylic acid, methacrylic acid, fumaric acid, itaconic acid, crotonic acid, and citraconic acid, and salts thereof. Dicarboxylic acids known to have an acid anhydride structure are preferably polymerized as the acid anhydride, and then hydrolyzed to synthesize a polymer copolymer. From the viewpoint of foam retention and quick rinsing properties, the structural unit derived from the component (b-1) is preferably a structural unit derived from a monomer containing one or more selected from the group consisting of acrylic acid or a salt thereof, maleic acid or a salt thereof, and maleic anhydride, and more preferably a structural unit derived from a monomer containing maleic acid. Examples of the salt include sodium salts and potassium salts. The salt of the copolymer may be formed by using a salt-type compound as a monomer, or may be formed by neutralization after copolymerization.

[0015] <(b-2) component> The olefin (b-2) having 4 to 12 carbon atoms and optionally having an aryl group can be one or more selected from butylene, isobutylene, diisobutylene, pentene, hexene, and styrene, preferably one or more selected from butylene, isobutylene, diisobutylene, pentene, hexene, and styrene, more preferably one or more selected from isobutylene, diisobutylene, and styrene, and even more preferably diisobutylene. From the viewpoint of rinsing properties, the number of carbon atoms of the olefin that may have an aryl group is preferably 4 to 8.

[0016] Component (b) is a polymer copolymer containing structural units derived from component (b-1) and structural units derived from component (b-2). In component (b), the molar ratio of structural units derived from component (b-1) to structural units derived from component (b-2) constituting component (b) [(b-1) / (b-2)] is preferably 10 / 90 or more, more preferably 15 / 85 or more, and even more preferably 25 / 75 or more, from the viewpoint of further improving stability and rinsing properties. Furthermore, from the viewpoint of suppressing re-foaming due to dilution during rinsing, it is preferably 90 / 10 or less, more preferably 85 / 15 or less, and even more preferably 75 / 25. The molar ratio [(b-1) / (b-2)] may be the molar ratio of the monomers used in the synthesis of component (b), unless the component (b-1) is a known product. Furthermore, when determining the molar ratio from a polymer, it can be determined by detecting the pyrolysis product of the copolymer using pyrolysis gas chromatography (PGC). Furthermore, in component (b), from the viewpoint of further improving rinsing properties, the total content of the structural units derived from component (b-1) and structural units derived from component (b-2) constituting component (b) is preferably from 90 mol% to 100 mol%, more preferably from 95 mol% to 100 mol%, and even more preferably from 98 mol% to 100 mol%, and it is preferable that the component (b) is a copolymer consisting essentially of structural units derived from component (b-1) and structural units derived from component (b-2). In the component (b), the total content of the structural units derived from the component (b-1) and the structural units derived from the component (b-2) that constitute the component (b) may be the total content of the components (b-1) and (b-2) relative to the total amount of monomers used in the synthesis of the component (b). The component (b) may be a salt, such as a sodium salt or a potassium salt.

[0017] The weight average molecular weight of component (b) is preferably 1,000 or more and 100,000 or less, more preferably 5,000 or more and 90,000 or less, and even more preferably 10,000 or more and 80,000 or less, from the viewpoints of foaming ability, foam retention, and rinsing ability. The weight-average molecular weight of the polymer copolymer of component (b), for example, diisobutylene-maleic acid copolymer, is a value determined by gel permeation chromatography using a mixture of acetonitrile and 0.1 M aqueous sodium chloride solution (acetonitrile:sodium chloride solution (volume ratio) = 30:70) as a developing solvent and polyethylene glycol as a standard substance.

[0018] <(c) component> Component (c) is one or more compounds selected from oxidizing halogen acids and their salts. Examples of oxidizing halogen acids for component (c) include hypochlorous acid, hypobromous acid, and chlorous acid, with hypochlorous acid being preferred from the viewpoint of bactericidal effect. Examples of salts of oxidizing halogen acids include alkali metal salts of hypochlorous acid, hypobromous acid, and chlorous acid. Component (c) is preferably an alkali metal salt of hypochlorous acid, more preferably sodium hypochlorite, from the viewpoint of further improving foam stability. When component (c) is used in the form of an acid and neutralized in the composition, safety must be ensured, and it is usually preferable to use it as a sodium salt in a high pH solution.

[0019] <(d) component> Component (d) is an alkali metal hydroxide. One or more types of component (d) can be used. Component (d) is preferably one or more types selected from sodium hydroxide and potassium hydroxide. From the viewpoint of further improving storage stability, component (d) preferably contains potassium hydroxide.

[0020] <Water> The remaining water in the liquid detergent composition for hard surfaces of the present invention is not particularly limited, but deionized water, distilled water, tap water, or groundwater can be used.

[0021] <Composition, optional ingredients, etc.> The liquid detergent composition for hard surfaces of the present invention contains component (a), converted into the sodium salt, in an amount of 1% by mass or more, preferably 1.5% by mass or more, in order to further enhance the foaming ability and foam retention of the diluted solution, and 8% by mass or less, preferably 5% by mass or less, more preferably 4% by mass or less, in order to further enhance the foaming ability and foam retention of the diluted solution. In this specification, unless otherwise specified, the mass of component (a) is the mass converted into the sodium salt.

[0022] In the liquid detergent composition for hard surfaces of the present invention, the content of component (b) in the composition is preferably 0.1% by mass or more, more preferably 0.4% by mass or more, and even more preferably 0.8% by mass or more, from the viewpoints of further improving the foam breaking property when diluted by rinsing and further suppressing re-foaming, and is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less, from the viewpoints of further improving the stability of the oxidizing halogen acid or its salt and the solution stability. In this specification, unless otherwise specified, the mass of component (b) is the mass converted into the sodium salt.

[0023] In the liquid detergent composition for hard surfaces of the present invention, the mass ratio of the content of component (a) to the content of component (b), [(a) / (b)], is 0.5 or more, preferably 0.8 or more, more preferably 1 or more, from the viewpoint of suppressing foaming due to the force of water during rinsing, and is 8 or less, preferably 5 or less, and even more preferably 4 or less, from the viewpoint of further enhancing foaming ability and foam stability.

[0024] The liquid detergent composition for hard surfaces of the present invention contains component (c), converted to a sodium salt, in an amount of 1% by mass or more, preferably 2% by mass or more, more preferably 3% by mass or more, and even more preferably 4% by mass or more in the composition, from the viewpoint of further enhancing the bactericidal effect, and 10% by mass or less, preferably 8% by mass or less, and more preferably 6% by mass or less in the composition, from the viewpoint of further enhancing storage stability. In this specification, unless otherwise specified, the mass of component (c) is the mass converted into the sodium salt. The content of component (c) can be determined by titration with hydrogen peroxide or the like.

[0025] The liquid detergent composition for hard surfaces of the present invention contains component (d) in an amount of preferably 0.5% by mass or more, more preferably 0.6% by mass or more, even more preferably 0.8% by mass or more, and even more preferably 1% by mass or more, in terms of adjusting the pH of the composition, and preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 6% by mass or less, in terms of further improving the stability and cleaning properties of the oxidizing halogen acid or its salt. The content of component (d) in the liquid detergent composition for hard surfaces of the present invention is a content that makes the pH of the liquid detergent composition for hard surfaces of the present invention 12 or higher, preferably 13 or higher. The content of alkali metal hydroxide is determined from the remaining alkali metal ions after counting the salts of components (a) to (c) and the optional components described below among the alkali metal ions contained in the composition.

[0026] From the viewpoint of suppressing whitening on the hard surface to be cleaned after treatment, the liquid detergent composition for hard surfaces of the present invention preferably contains a small amount of alkali metal silicate or no alkali metal silicate at all. That is, the liquid detergent composition for hard surfaces of the present invention does not contain any alkali metal silicate, or the content of alkali metal silicate in the composition is preferably 0.2% by mass or less, more preferably 0.1% by mass or less, and more preferably is substantially free of alkali metal silicate. The liquid detergent composition for hard surfaces of the present invention optionally contains an alkali metal silicate, and the content of the alkali metal silicate in the composition is 0.2% by mass or less, preferably 0.1% by mass or less, and preferably 0% by mass or more, more preferably 0% by mass. Examples of the salts of alkali metal silicates include alkali metal salts, specifically sodium salts and potassium salts.

[0027] <Other ingredients> The liquid detergent composition for hard surfaces of the present invention requires rinsing after contacting the foam generated by foaming the composition or a diluted solution of the composition with the object to be cleaned. From the viewpoint of improving rinsing properties, the composition may optionally contain (e) a branched fatty acid salt having from 11 to 25 carbon atoms (hereinafter referred to as component (e)). In addition, in order to further improve storage stability, the liquid detergent composition for hard surfaces of the present invention may optionally contain (f) an alkylbenzenesulfonate salt substituted with 1 to 3 alkyl groups having 1 to 3 carbon atoms [hereinafter referred to as component (f)]. Components (e) and (f) may be used in the form of an acid and then neutralized in the composition.

[0028] <(e) component> Component (e) is a branched fatty acid salt having a chain-like branched hydrocarbon group having from 11 to 25 carbon atoms. Examples of salts of component (e) include sodium salts and potassium salts. The component (e) may be a branched fatty acid salt used alone or in combination of two or more. The branched hydrocarbon group is an alkyl group or an alkenyl group, with an alkyl group being preferred. The branched hydrocarbon group of component (e) has 11 or more carbon atoms, preferably 13 or more, more preferably 15 or more, and 25 or less, preferably 23 or less, more preferably 21 or less, and even more preferably 17 or less. Examples of component (e) include the organic acid salts described in paragraph 0027 of JP 2019-73732 A, in which, if the carbon atom bonded to the carbonyl carbon is a secondary carbon atom, the fatty acid having a straight-chain alkyl group is also a branched fatty acid, and examples thereof include isopalmitate, isostearate, and isoarachidate. Component (e) is preferably at least one selected from isostearate and isoarachidate.

[0029] Other examples of the branched fatty acid of component (e) include a mixture of branched aliphatic primary carboxylic acids having one to three, preferably one, methyl group at the third or higher position of the main chain of an aliphatic primary monocarboxylic acid, but with different branching positions (hereinafter sometimes referred to as methyl-branched fatty acids) and / or salts thereof. The mixture is preferably a mixture of two or more, more preferably three or more, and preferably twelve or fewer, more preferably eleven or fewer species. Component (e) can be commercially available, and branched fatty acids with different structures can be mixed. When producing it, the production method is not particularly limited. However, a mixture of fatty acids having methyl-branched chain-branched hydrocarbons with different branching positions can be prepared, for example, as a by-product in the process of polymerizing unsaturated fatty acids with one or more double bonds using an acid catalyst. For example, the production method described in Japanese Patent No. 3303947 can be used to obtain a mixture of saturated methyl-branched fatty acids with different branching positions. Whether the resulting branched fatty acids are a mixture of fatty acids with different branching positions can be confirmed by separation using GC-MS. With regard to component (e), a mixture in which the branching positions of the side chains are distributed at positions 3 or higher on the main chain is more likely to form the oily domains that are a feature of the present invention than a single component in which the branching positions of the side chains are the same, and therefore the foam of the liquid detergent composition for hard surfaces has better rinsing properties. Also, from the viewpoint of production costs, this is preferable to obtaining a single component in which the branching positions of the side chains are the same.

[0030] When the liquid detergent composition for hard surfaces of the present invention contains component (e), the liquid detergent composition for hard surfaces of the present invention contains component (e) in an amount of preferably 0.001% by mass or more, more preferably 0.005% by mass or more, even more preferably 0.1% by mass or more in order to further improve rinsing properties, and preferably 1.0% by mass or less, more preferably 0.8% by mass or less, even more preferably 0.6% by mass or less in order to further improve uniform solubility. In this specification, unless otherwise specified, the mass of component (e) is the mass converted into the sodium salt.

[0031] <Component (f)> Component (f) is an alkylbenzenesulfonate substituted with one to three alkyl groups having 1 to 3 carbon atoms. One or more types of component (f) can be used. The salt of component (f) is preferably a sodium or potassium salt. Specific examples of component (f) include sodium paratoluenesulfonate, potassium paratoluenesulfonate, sodium metaxylenesulfonate, potassium metaxylenesulfonate, sodium cumenesulfonate, and potassium cumenesulfonate, which are known as hydrotropes.

[0032] When the liquid detergent composition for hard surfaces of the present invention contains component (f), the liquid detergent composition for hard surfaces of the present invention contains component (f) in an amount of preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 0.8% by mass or more, and preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 3% by mass or less, in order to further enhance low-temperature storage stability.

[0033] <(g) component> The liquid detergent composition for hard surfaces of the present invention may optionally contain (g) an alkyl sulfate ester salt in which the alkyl group has 8 to 18 carbon atoms (hereinafter referred to as component (g)). One or more types of component (g) may be used. Component (g) is a preferred component from the viewpoint of suppressing the occurrence of cloudiness when diluted to a low concentration. The alkyl sulfate salt of component (g) is preferably an alkyl sulfate salt having an alkyl group having 8 or more, preferably 10 or more, and 18 or less, preferably 16 or less, more preferably 14 or less, and even more preferably 12 or less carbon atoms, and further preferably a straight-chain or branched-chain alkyl group. Component (g) is preferably an alkyl sulfate having an alkyl group derived from a primary aliphatic alcohol. Component (g) may be used in the form of an acid and neutralized in the composition.

[0034] Examples of salts of component (g) include alkali metal salts such as sodium salts and potassium salts, alkaline earth metal salts such as magnesium salts, ammonium salts, and organic amine salts such as monoethanolamine salts, diethanolamine salts, and triethanolamine salts, with alkali metal salts being preferred, and sodium salts being more preferred.

[0035] When the liquid detergent composition for hard surfaces of the present invention contains component (g), the liquid detergent composition for hard surfaces of the present invention contains component (g) in an amount, calculated as a sodium salt, of preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.4% by mass or more, in order to further improve the foaming ability and foam retention of the diluted solution, and preferably 8% by mass or less, more preferably 5% by mass or less, and even more preferably 4% by mass or less, in order to further improve the foaming ability and foam retention of the diluted solution and the stability when diluted with hard water. In this specification, unless otherwise specified, the mass of component (g) is the mass converted into the sodium salt.

[0036] <Optional ingredients> In addition to components (a) to (d) and optional components (e) to (g), the liquid detergent composition for hard surfaces of the present invention may contain other components, such as a copolymer of acrylic acid and a polymerizable monomer, a chelating agent such as succinic acid or citric acid; a water-soluble solvent such as diethylene glycol monobutyl ether; a pH adjuster, a thickener, a viscosity adjuster, a fragrance, a colorant, an antioxidant, or a preservative, within the scope of the object of the present invention (excluding those corresponding to components (a) to (g)).

[0037] The liquid detergent composition for hard surfaces of the present invention can contain other surfactants. For example, fatty acid salts or alkyl sulfate ester salts having 8 to 10 carbon atoms may be contained for the storage stability of the liquid detergent composition. Also, the amine oxide type surfactant is 0.5% by mass or less, preferably 0.2% by mass or less, more preferably substantially not contained. Also, as the chelating agent, methylglycine diacetate, ethylenediaminetetraacetate, nitrilotriacetate, polyoxyethylene alkylamine which is a surfactant, and amine compounds such as alkanolamine as an alkaline agent are also preferably substantially not contained from the viewpoint of further enhancing the stability of hypochlorite.

[0038] The remainder constituting the liquid detergent composition for hard surfaces of the present invention is water. The composition contains water. That is, in the composition of the present invention, it is preferable that the remainder other than the components (a) to (d) and optional components is water. The liquid detergent composition for hard surfaces of the present invention can contain water, preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 75% by mass or more, even more preferably 80% by mass or more, and preferably less than 94% by mass, more preferably 93% by mass or less. It is preferable to use deionized water, sterilized deionized water, etc. for water.

[0039] The pH of the liquid detergent composition for hard surfaces of the present invention at 25°C is 12 or more, preferably 12.5 or more, more preferably 12.8 or more, still more preferably 13.0 or more, and, for example, 14 or less from the viewpoint of further enhancing the stability and detergency of the oxidizing halogen acid or its salt. The pH of the composition at 25°C can be measured by the glass electrode method. The pH of the liquid detergent composition for hard surfaces of the present invention at 25°C is specifically measured by the following pH measurement method.

[0040] <pH Measurement Method> A pH measurement composite electrode (glass ground sleeve type, manufactured by Horiba, Ltd.) is connected to a pH meter (pH / ion meter F-23, manufactured by Horiba, Ltd.) and the power is turned on. A saturated potassium chloride aqueous solution (3.33 mol / L) is used as the internal solution of the pH electrode. Next, a pH 6.86 standard solution (neutral phosphate standard solution), a pH 9.18 standard solution (borate standard solution), and a pH 12.0 standard solution (saturated calcium hydroxide standard solution) are each filled into a 100 mL beaker and immersed in a thermostatic bath at 25°C for 30 minutes. The pH measurement electrode is immersed in the thermostatically adjusted standard solution for 3 minutes, and calibration is performed in the order of pH 6.86 → pH 9.18 → pH 12.0. The sample to be measured (the liquid cleaning composition for hard surfaces of the present invention) is adjusted to 25°C, the electrode of the pH meter is immersed in the sample, and the pH is measured after 1 minute.

[0041] The pH at 25°C of a diluted solution obtained by diluting the liquid detergent composition of the present invention with water can also be measured in the same manner. In this case, in the above description, the liquid detergent composition for hard surfaces of the present invention shall be read as a diluted solution obtained by diluting the liquid detergent composition of the present invention with hard water.

[0042] The liquid detergent composition for hard surfaces of the present invention may be a liquid detergent composition for hard surfaces that is diluted with hard water before use. The hard surface liquid cleaning composition of the present invention may also be a liquid cleaning composition for hard surfaces that is foamed before use. The hard surface liquid cleaning composition or a diluted solution of the hard surface liquid cleaning composition diluted with water can be foamed using a foaming cleaning device commonly used in kitchens, supermarket backrooms, food processing plants, and the like. Specifically, simple methods include filling a container equipped with a foaming device, such as a net, into a trigger-type or extrusion pump-type injection mechanism, and foaming the composition; or a foaming device (hereinafter sometimes referred to as a trigger sprayer or foamer sprayer) that is directly attached to a tap and has the function of mixing the hard surface liquid cleaning composition filled in a parallel tank at an arbitrarily set dilution ratio and foaming and releasing the mixture. The foaming device may also be a pressure-accumulating type.

[0043] The hard water used to dilute the liquid detergent composition for hard surfaces of the present invention is generally assumed to be water containing hard components, such as tap water or groundwater. From the viewpoint of further improving foaming ability and foam retention, the hardness of the water used for dilution is preferably in the range of 1° dH to 20° dH, more preferably in the range of 1° dH to 18° dH, even more preferably in the range of 1° dH to 15° dH, even more preferably in the range of 1° dH to 10° dH, and even more preferably in the range of 2° dH to 8° dH.

[0044] The liquid detergent composition for hard surfaces of the present invention can be used as is or after dilution. When the liquid detergent composition for hard surfaces of the present invention is diluted, the dilution ratio of the liquid detergent composition for hard surfaces of the present invention varies depending on the object to be cleaned and the cleaning range. However, a lower dilution ratio is preferred when detergency and rapid sterilization are required, while a higher dilution ratio may be used when spraying foam over a wide area of ​​floors or walls for daily cleaning. The present invention provides a composition that is easy to use, as it can foam from the undiluted solution to diluted aqueous solution without clogging. Therefore, the dilution ratio is preferably 2 to 60 times, more preferably 2 to 20 times, and even more preferably 4 to 10 times.

[0045] The diluted solution obtained by diluting the liquid detergent composition for hard surfaces of the present invention with water (hereinafter referred to as the diluted solution of the present invention) contains component (a) in an amount of preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more in order to further enhance foaming power and cleaning properties, and preferably 2% by mass or less, more preferably 1.5% by mass or less, and even more preferably 1% by mass or less in order to further enhance rinsing properties.

[0046] The dilution solution of the present invention contains component (b) in an amount of preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, from the viewpoint of further improving the bubble breaking ability and further suppressing re-foaming, and preferably 0.8% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.3% by mass or less, from the viewpoint of further improving the stability of the oxidizing halogen acid or its salt.

[0047] The diluted solution of the present invention contains component (c) in an amount of preferably 0.01% by mass or more, more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more, from the viewpoint of further improving the stability, cleaning properties, and disinfecting performance of the oxidizing halogen acid or its salt, and preferably 3% by mass or less, more preferably 2.5% by mass or less, and even more preferably 2% by mass or less, from the viewpoint of safety and further reducing the effect on other substrates.

[0048] From the viewpoint of pH adjustment, the dilution solution of the present invention contains component (d) in an amount of preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and preferably 3% by mass or less, more preferably 2.5% by mass or less, and even more preferably 2% by mass or less.

[0049] When the diluted solution of the present invention contains component (e), the diluted solution of the present invention contains component (e) in an amount of preferably 0.01% by mass or more, more preferably 0.02% by mass or more, and even more preferably 0.03% by mass or more in order to further improve rinsing properties, and preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.4% by mass or less in order to further improve foaming power and foam retention.

[0050] When the dilution solution of the present invention contains component (f), the dilution solution of the present invention contains component (f) in an amount of preferably 0.01% by mass or more, more preferably 0.03% by mass or more, and even more preferably 0.05% by mass or more in order to further enhance low-temperature stability, and preferably 1.5% by mass or less, more preferably 1% by mass or less, and even more preferably 0.8% by mass or less in order to further enhance the stability of the oxidizing halogen acid or its salt.

[0051] When the dilution solution of the present invention contains component (g), the dilution solution of the present invention contains component (g) in an amount of preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more in order to further improve foaming power and solution stability upon dilution, and preferably 2% by mass or less, more preferably 1.5% by mass or less, and even more preferably 1% by mass or less in order to further improve foam retention.

[0052] In the diluted solution of the present invention, the mass ratio of the content of component (a) to the content of component (b) contained in the diluted solution [(a) / (b)] is the same as the mass ratio [(a) / (b)] in the liquid cleaning composition for hard surfaces of the present invention. These diluted solutions are foamed using a foaming device, for example, a foaming device connected to a water supply or a manual sprayer, to produce a foamed solution, which is then brought into contact with the object to be cleaned, for cleaning. The detailed process will be described later.

[0053] The pH of the diluted solution of the present invention at 25°C is preferably 11 or more, more preferably 12 or more, even more preferably 12.5 or more, still more preferably 13 or more, and is preferably, for example, 14 or less, from the viewpoint of further enhancing the stability and cleaning properties of the oxidizing halogen acid or its salt.

[0054] To enhance operability, the viscosity of the liquid cleaning composition for hard surfaces of the present invention at 25°C is preferably 0.5 mPa·s or more, more preferably 1 mPa·s or more, and preferably 500 mPa·s or less, more preferably 200 mPa·s or less, even more preferably 100 mPa·s or less, even more preferably 80 mPa·s or less, and even more preferably 50 mPa·s or less. The viscosity can be adjusted using a solvent, hydrotropic agent, or the like. This viscosity is measured using a Brookfield viscometer, using the rotor recommended for the viscosity being measured (one of the No. 1 to No. 3 rotors), at 60 r / min, and the reading is taken 1 minute after the start of measurement. The liquid cleaning composition for hard surfaces is measured at a temperature adjusted to 25±1°C. If multiple rotors satisfy the conditions, the value measured using the rotor with the smaller number is used.

[0055] The liquid detergent composition for hard surfaces of the present invention is preferably used for the hard surfaces of hard articles, and further for food processing equipment and / or cooking equipment in the backrooms of supermarkets, or similar equipment in the kitchens of restaurants. That is, the present invention is preferably a liquid detergent composition for food processing equipment and / or cooking equipment. In the present invention, the term "food processing equipment and / or cooking equipment" refers to equipment and facilities used in processing and / or cooking food. Examples of such equipment include slicers, meat mincers (food processors), knives, cutting boards, etc. Furthermore, examples of such facilities include floors, walls, work tables, cooking ranges, refrigerators, etc.

[0056] When the liquid detergent composition for hard surfaces of the present invention is used for food processing equipment and / or cooking equipment, it is preferable to clean the "food processing equipment and / or cooking equipment" by foam cleaning.

[0057] <How to clean hard surfaces> The method for cleaning a hard surface of the present invention is a method for cleaning a hard surface, which comprises contacting the liquid detergent composition for hard surfaces of the present invention or a diluted solution obtained by diluting the composition with hard water with the hard surface. That is, the method for cleaning hard surfaces of the present invention uses the liquid detergent composition for hard surfaces of the present invention. Preferred embodiments of the composition are the same as those of the liquid detergent composition for hard surfaces of the present invention described above.

[0058] The liquid detergent composition for hard surfaces of the present invention is suitably used in a method for cleaning hard surfaces, which method comprises the following steps 1 to 3. In steps 1 to 3, the hard surface is suitably the surface of food processing equipment and / or cooking equipment. Step 1: A step of spraying the liquid detergent composition for hard surfaces in the form of foam while pre-diluting and / or diluting the liquid detergent composition for hard surfaces with hard water at a dilution ratio of 2 to 60 times, and applying the diluted liquid detergent composition for hard surfaces (hereinafter referred to as the foam diluted solution) to the hard surface. Step 2: A step of leaving the foamy diluted solution attached to the hard surface on the hard surface for a certain period of time. Step 3: Rinse the hard surface with the diluted foam solution with water.

[0059] In step 1, the liquid detergent composition for hard surfaces of the present invention is pre-diluted with water at a dilution ratio of 2 to 60 times, preferably 2 to 20 times, and then sprayed in the form of foam. Alternatively, the liquid detergent composition for hard surfaces is placed in a dedicated container and directly connected to a water supply via a hose or the like, and mixed while being diluted and sprayed in the form of foam. The above-mentioned pre-dilution and simultaneous dilution can also be combined to spray a diluted solution of the liquid detergent composition for hard surfaces in the form of foam. The dilution ratio in step 1 is 2 to 60 times, preferably 2 to 20 times, and more preferably 4 to 10 times.

[0060] Here, the water used for dilution is generally assumed to be water containing hardness components, such as tap water. From the viewpoint of foam continuity, the hardness of the water used for dilution is preferably in the range of 1° dH to 20° dH, more preferably in the range of 1° dH to 18° dH, even more preferably in the range of 1° dH to 15° dH, even more preferably in the range of 1° dH to 10° dH, and even more preferably in the range of 2° dH to 8° dH.

[0061] A preferred embodiment of spraying a diluted solution of the liquid detergent composition for hard surfaces of the present invention in foam form is to fill a dedicated foam washer with an appropriate amount of diluted solution diluted with water to a predetermined ratio and spray the solution in foam form by mixing with external air / compressed air. For large treatment areas such as floors and walls, an electric foam washer is preferred, although a device simply equipped with an electric pump and a foaming component may also be used. For small treatment areas such as cutting boards and other cooking utensils, a hand sprayer capable of intermittently generating foam, such as a trigger sprayer or foamer sprayer, is preferred. Even when using a hand sprayer, the liquid detergent composition of the present invention can be foamed even when diluted 20 times or less, or even 10 times or less, from the original solution. In this case, it is preferable to include component (g).

[0062] It is preferable to spray the foam without interruption in step 1. Here, "without interruption" spraying means, for example, using a foam washer, the cleaning agent continues to spray in foam continuously (for example, for 5 seconds or more) while the tap is opened with a lever or switch, and this is to be distinguished from "intermittent" spraying, for example, using a hand sprayer such as a trigger sprayer or foam sprayer, in which spraying begins when the lever is pulled and then stops instantly.

[0063] The embodiment of continuously spraying foam using a foam washer is particularly effective when the area and size of the food processing equipment and / or cooking equipment to be cleaned is large.

[0064] When a foam washer is used, the foaming ratio (ratio of foam volume (mL) / foam mass (g)) is preferably 3 to 50 times, more preferably 5 to 40 times, and even more preferably 10 to 40 times. The pressure (gauge pressure) during spraying is preferably 0.1 to 1 MPa, more preferably 0.2 to 0.8 MPa, and even more preferably 0.2 to 0.5 MPa. When a hand sprayer such as a trigger sprayer or foamer sprayer is used, the foaming ratio is preferably 2 to 30 times, more preferably 2 to 20 times, and even more preferably 3 to 10 times. The liquid detergent composition for hard surfaces of the present invention is resistant to clouding when diluted, and has excellent foaming and foam retention. Furthermore, clogging of the foaming device can be suppressed.

[0065] In step 1, a diluted solution of the liquid detergent composition for hard surfaces of the present invention is sprayed in the form of foam, and the diluted foam solution is attached to a hard surface, preferably food processing equipment and / or cooking equipment, and then maintained for a certain period of time (step 2). Step 2 may be a step of maintaining the sprayed foam for a certain period of time. In step 2, the maintenance time is preferably 1 to 60 minutes, more preferably 1 to 45 minutes, from the viewpoint of further improving the mechanism and operability of each device. Furthermore, this time is preferably 1 to 30 minutes, more preferably 1 to 20 minutes, even more preferably 1 to 15 minutes, even more preferably 1 to 10 minutes, and even more preferably 1 to 5 minutes. In addition, in step 2, the maintenance time is preferably 10 to 60 minutes, more preferably 15 to 45 minutes, and even more preferably 20 to 30 minutes, from the viewpoint of further improving cleaning performance.

[0066] The time for which the solution is maintained for a certain period of time in step 2 varies depending on the dilution ratio of the diluted solution and the situation of use, and is not particularly limited. For example, when the dilution ratio is 2 to 30 times (preferably 2 to 20 times), the foam is maintained for 1 to 60 minutes, and when the dilution ratio is 30 to 60 times, it is preferable to maintain the foam stably for 1 to 10 minutes.

[0067] It is preferable to leave the mixture as it is while maintaining the foam in step 2, but it is also possible to add a small amount of water or the like.

[0068] After the foamy diluted solution is maintained for a certain period of time in step 2, in step 3, the hard surface to which the foamy diluted solution is attached, preferably food processing equipment and / or cooking equipment, is rinsed with water. The temperature of the rinsing water is preferably 10 to 70°C, more preferably 20 to 70°C. Tap water can be used as the rinsing water, and it may be heated to adjust to the above-mentioned preferred water temperature. Generally, rinsing is performed by hand using a hose or the like. If the surface is sufficiently waterproof, water may be poured over it using a bucket or the like. [Example]

[0069] Liquid detergent compositions for hard surfaces shown in Table 1 were prepared using the following components (a) to (e), and the following items were evaluated. The results are shown in Table 1. The mass % of each component in Table 1 is all based on the pure content. The liquid detergent compositions for hard surfaces shown in Table 1 have excellent foam stability and can therefore be said to have excellent cleaning performance.

[0070] <Component (a)> LAS: Sodium dodecylbenzenesulfonate (Neopelex G-25, manufactured by Kao Corporation) The component (a), sodium dodecylbenzenesulfonate, contains a compound in which the carbon atom of the alkyl group bonded to the benzene ring is the second carbon atom.

[0071] <(b) Component> Accusol ND: Diisobutylene-maleic acid copolymer (manufactured by Rohm and Hass), active content 92%, copolymerization ratio (molar ratio) = (b-1) / (b-2) = maleic acid / diisobutylene = 1.0, weight average molecular weight 10,000 Demol ST: styrene-maleic acid copolymer (Kao Corporation), copolymerization ratio (molar ratio) = (b-1) / (b-2) = maleic acid / styrene = 1, weight average molecular weight 10,000 Demol EP: Diisobutylene-maleic acid copolymer (Kao Corporation), copolymerization ratio (molar ratio) = (b-1) / (b-2) = maleic acid / diisobutylene = 1, weight average molecular weight 20,000 (b) The weight-average molecular weight of component (b) was measured by gel permeation chromatography using acetonitrile / 0.1 M sodium chloride aqueous solution (30 / 70) as the developing solvent and polyethylene glycol as the standard substance. <(b') component> Sodium polyacrylate: Trade name: Sokalan PA25CL, manufactured by BASF, weight average molecular weight 4000

[0072] <(c) component> Sodium hypochlorite <(d) component> Potassium hydroxide <(e) component> Isostearic acid EX: Methyl-branched sodium stearate with branches at 3 or more positions (manufactured by Kokyu Alcohol Kogyo Co., Ltd.) <(g) component> C10AS: Sodium decyl sulfate (EMAL 3F, manufactured by Kao Corporation)

[0073] (1) Method for producing a liquid cleaning composition for hard surfaces A stirrer piece and purified water were placed in a beaker, and while stirring the purified water, components (a), (b), (c), and optional components (e) and (g) were added. Next, component (d) was added to this mixture so that the pH was 12, and the mixture was stirred until it reached room temperature. After the mixture reached room temperature, component (d) was added and stirred until the pH was 13, thereby producing a liquid cleaning composition for hard surfaces of the present invention.

[0074] (2) Measurement of minimum foaming dilution ratio (minimum foaming concentration) The liquid detergent composition solution for hard surfaces was diluted 1,000 to 50,000 times with 4°dH hardness water to prepare solutions. The diluted solutions prepared were each placed in a 20 mL glass bottle (diameter 27 mm, height 55 mm) so that the total volume was 10 mL, and the solution was mixed well by hand 20 times. The dilution ratio at which no foaming was observed was evaluated as the dilution ratio at which minimal foaming occurred. The results are shown in Table 1. The lower the dilution ratio for minimum foaming, the less foaming the composition will be, without using a large amount of water, and therefore the foam will be more easily broken by dilution, making it easier to rinse, and as a result, the time required for rinsing will be shorter. The concentration of the hard surface liquid detergent composition in the diluted solution at the dilution ratio for minimum foaming is the minimum foaming concentration, and this concentration means the concentration of the composition in water at which further dilution will no longer foam. The higher this minimum foaming concentration, the less foaming the composition will be, without using a large amount of water, and therefore the more foaming the composition will be, with the more foaming the composition will be, with the more foaming the composition will be, with the more easily rinsing, and as a result, the time required for rinsing will be shorter.

[0075] (3) Evaluation method for foam stability 0.1 g of the liquid detergent composition solution for hard surfaces shown in Table 1 was placed in a 9 mL glass bottle (diameter 21 mm, height 45 mm) and diluted 40 times with 4° dH hardness water. The glass bottle was then shaken vigorously by hand 20 times. The foam height (cm) was measured immediately after shaking and 30 minutes later, and the foam stability (%) was calculated using formula (1). Foam stability is the rate of change in foam height between immediately after shaking and 30 minutes later. Higher foam stability indicates better foam retention and also indicates that the composition functions as a detergent. The foam stability of the composition of Comparative Example 1-1 could be measured, but it was a composition with relatively poor foaming. The composition of Comparative Example 1-3 was a composition with relatively poor foam retention and foam quality. Foam stability (%) = (foam height after 30 minutes (cm)) / (foam height immediately after (cm)) × 100 (1)

[0076] The compositions of Examples 1-5 and 1-6 contained component (e), which improved rinsing properties, and Example 1-7 contained a relatively large amount of component (a), which improved foam quality.

[0077] [Table 1]

Claims

1. (a) 1% by mass or more and 8% by mass or less of alkylbenzenesulfonate having an alkyl group having 10 to 18 carbon atoms; (b) a polymer copolymer containing a structural unit derived from (b-1) a carboxylic acid or a salt thereof having a reactive unsaturated group having from 3 to 6 carbon atoms and a structural unit derived from (b-2) a polymerizable olefin having from 4 to 12 carbon atoms and optionally having an aryl group; (c) an oxidizing halogen acid or a salt thereof in an amount of 1% by mass or more and 10% by mass or less; (d) alkali metal hydroxides; and water, wherein the mass ratio of the content of the component (a) to the content of the component (b), [(a) / (b)], is 0.5 or more and 8 or less, and the pH at 25°C is 12 or more.

2. The liquid cleaning composition for hard surfaces according to claim 1, which is diluted with hard water before use.

3. 3. The liquid cleaning composition for hard surfaces according to claim 1, which is foamed before use.

4. The liquid detergent composition for hard surfaces according to claim 2, wherein the hardness water is water having a hardness of 1° dH or more and 20° dH or less.

5. A method for cleaning a hard surface, comprising contacting the liquid detergent composition for hard surfaces according to claim 1 or a diluted solution obtained by diluting said composition with hard water with the hard surface.

6. 6. The method for cleaning a hard surface according to claim 5, comprising the following steps 1 to 3: Step 1: A step of diluting the liquid detergent composition for hard surfaces with hard water at a dilution ratio of 2 to 60 times in advance and / or spraying the diluted liquid detergent composition for hard surfaces in the form of foam while diluting the composition, and applying the diluted liquid detergent composition for hard surfaces (hereinafter referred to as the foam diluted solution) to the hard surface. Step 2: A step of leaving the foamy diluted solution attached to the hard surface on the hard surface for a certain period of time. Step 3: Rinse the hard surface with the diluted foam solution with water.

7. 7. The method for cleaning a hard surface according to claim 5 or 6, wherein the hard surface is a surface of food processing equipment and / or cooking equipment.

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