Liquid detergent composition for dishwashers

Abstract

To provide a liquid detergent composition for dishwashing machines that has high capability of cleaning oil stains with only a small amount of an acrylic acid polymer serving as a dispersant or a thickener blended therein, and can give a clean finish of an article having a hydrophobic surface.SOLUTION: The present invention provides a liquid detergent composition for dishwashing machines containing (a) a sulfosuccinic acid branched alkyl ester in which a branched alkyl group has 9-11 carbon atoms, (b) a thickener (excluding thickeners comprising polymers that include acrylic acid as a monomer unit), and water.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a liquid detergent composition for dishwashers. [Background technology]

[0002] Examples of stains that adhere to tableware include oil stains, starch stains such as rice grains, protein stains such as eggs, and pigment stains such as tea. Among these, oil stains are difficult to remove, and there is a problem that they reattach to the tableware when washed in a dishwasher. In order to improve the cleaning power against oil stains, various methods have been proposed to date, such as the type and formulation of surfactants, which are the active ingredients for cleaning. Patent Document 1 discloses the technology of an automatic dishwashing detergent containing an anionic surfactant such as dialkyl sulfosuccinic acid. Patent Document 2 also discloses the technology of using dialkyl sulfosuccinic acid with a specific structure in a dishwashing detergent.

[0003] However, using a large amount of surfactant in dishwasher detergents results in excessive foaming, causing foam to overflow inside the machine and actually reducing cleaning power. Therefore, it is desirable to emulsify the oil adhering to dishes with a very small amount of surfactant, but the dispersed oil will re-adhere to the dishes because there is little surfactant. For this reason, a technique is commonly used in which polymer dispersants such as polyacrylic acid are added to disperse the emulsified oil and prevent re-adhesion. Patent Document 3 discloses a technology for a concentrated liquid detergent composition for automatic dishwashers that contains a polycarboxylic acid type polymer and does not re-adhere. In addition, liquid detergents for dishwashers are thickened using thickeners for ease of use, and polyacrylic acid-based thickeners are also commonly used. Patent Document 4 discloses a technology containing a sulfosuccinate type surfactant and a polycarboxylic acid type thickener. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2019-182904 [Patent Document 2] Japanese Patent Publication No. 2017-214554 [Patent Document 3] Japanese Patent Publication No. 2019-035099 [Patent Document 4] Japanese Patent Publication No. 2016-145306 [Overview of the project] [Problems that the invention aims to solve]

[0005] When cleaning items with hydrophobic surfaces, such as polypropylene, using a liquid dishwasher detergent containing polymer dispersants such as polyacrylic acid or polymer thickeners, white spots may appear on the surface after washing and drying, significantly impairing the finish. The inventors have clarified that the cause of these white spots is a complex between calcium and acrylic polymers. To resolve this white spot problem, it is conceivable to omit or reduce the amount of polymer dispersant used. However, removing the polymer dispersant impairs the dispersion of emulsion droplets, leading to a significant decrease in cleaning power. Furthermore, reducing the amount of polymer dispersant can lead to the re-adhesion of oily stains to dishes during rinsing, exacerbating the deterioration of the finish, such as cloudiness. Users of dishwashers sometimes load more dishes into the washing machine than the recommended standard amount, and it is desirable that the cleaning effect and finish do not deteriorate even in such cases.

[0006] The present invention provides a liquid detergent composition for dishwashers that exhibits excellent cleaning power against oil stains and superior finish on articles with hydrophobic surfaces, even with a small amount of acrylic acid-based polymers that function as dispersants and thickeners. [Means for solving the problem]

[0007] The present invention relates to a liquid detergent composition for a dishwashing machine, which contains (a) a branched alkyl sulfosuccinate ester in which the branched alkyl group is a branched alkyl group having 9 to 11 carbon atoms [hereinafter referred to as component (a)], (b) a thickener [however, a thickener composed of a polymer containing acrylic acid as a monomer unit is excluded] [hereinafter referred to as component (b)], and water.

Effects of the Invention

[0008] According to the present invention, there is provided a liquid detergent composition for a dishwashing machine, which has excellent detergency against oil stains and excellent finish of articles having a hydrophobic surface, even when the amount of an acrylic polymer functioning as a dispersant or a thickener is small.

Modes for Carrying Out the Invention

[0009] <Liquid Detergent Composition for Dishwashing Machine> Component (a) is a branched alkyl sulfosuccinate ester in which the branched alkyl group is a branched alkyl group having 9 to 11 carbon atoms.

[0010] Examples of component (a) include those in which the ester is a monoester and those in which the ester is a diester. Preferably, it is a branched alkyl sulfosuccinate diester in which each of the two branched alkyl groups is a branched alkyl group having 9 to 11 carbon atoms.

[0011] The branched alkyl group of component (a) is preferably a branched alkyl group having a main chain of 6 or 7 carbon atoms and one or more side chains, and the total number of carbon atoms in the side chains is 3. The branched alkyl group of component (a) is preferably a branched alkyl group selected from a 2-propylheptyl group and a 3,5,5-trimethylhexyl group.

[0012] Examples of component (a) include branched sulfosuccinate esters represented by the following general formula (a1).

[0013]

Chemical formula

[0014] [In the formula, R 1a , R 2a are each independently a branched alkyl group having 9 to 11 carbon atoms. A 1 , A 2 are each independently an alkylene group having 2 to 4 carbon atoms, and x and y are the average number of moles of addition and are each independently 0 or more and 6 or less. M 1 is a hydrogen atom or a cation. ]

[0015] Furthermore, as the component (a), a sulfosuccinic acid branched alkyl ester represented by the following general formula (a1-1) can be mentioned. This compound is a compound of the general formula (a1) where x = 0 and y = 0.

[0016] [Chemical formula]

[0017] [In the formula, R 1a , R 2a are each independently a branched alkyl group having 9 to 11 carbon atoms. M 1 is a hydrogen atom or a cation. ]

[0018] The following description is applicable to each of the general formula (a1) and the general formula (a1-1). R 1a , R 2a may have the same or different number of carbon atoms. In the present invention, a hydrocarbon residue obtained by removing a hydroxyl group from a secondary alcohol is included in the chain-branched hydrocarbon group.

[0019] In the present invention, among the chain-branched hydrocarbon groups of R 1a , R 2a , the hydrocarbon chain having the largest number of carbon atoms counted from the carbon atom bonded to the oxygen atom is defined as the main chain, and the hydrocarbon chain branched and bonded from the main chain is defined as the side chain. When two or more main chains are conceivable, that is, when there are two or more hydrocarbon chains having the largest number of carbon atoms (hereinafter also referred to as the longest hydrocarbon chain), the main chain is determined in the following order. 1. The side chain branching from the longest hydrocarbon chain with the larger number of carbon atoms is designated as the main chain. 2. Next, if the number of carbon atoms in the side chains branching from the longest hydrocarbon chain is the same, the one with more side chains branching from the longest hydrocarbon chain will be considered the main chain. 3. Next, if the number of side chains branching from the longest hydrocarbon chain is the same, the chain with the side chains closer to the oxygen atom (counting from the carbon atom bonded to the oxygen atom) is considered the main chain. 4. Next, if the carbon atoms in the side chains closest to the oxygen atom are in the same position, the one with more carbon atoms in the side chain closest to the oxygen atom will be considered the main chain. Furthermore, if two or more longest hydrocarbon chains have the same symmetrical structure, either one may be used as the main chain.

[0020] R 1a , R 2a In each branched alkyl group, the total number of carbon atoms constituting the side chain may be the same or different, but from the viewpoint of cleaning properties such as solid fats and foam suppression, it is preferably 3. In this invention, the total number of carbon atoms constituting the side chains refers to the sum of the carbon atoms in all side chains other than the main chain in a single branched alkyl group, and if there are multiple side chains, it refers to the sum of the carbon atoms in all of those side chains.

[0021] R 1a , R 2a The number of side chains may be the same or different, and from the viewpoint of cleaning properties such as solid fats and foam suppression, it is 1 or more, preferably 3 or less, and more preferably 2 or less. In the present invention, the number of side chains refers to the number of side chains branching from the main chain, and the number of side chains does not change even if a side chain has further side chains branching from it. However, from the viewpoint of cleaning properties and foam suppression properties for solid fats, etc., a side chain may have further side chains branching from it.

[0022] R 1a , R 2aThe number of branched carbon atoms may be the same or different, and from the viewpoint of cleaning properties such as solid fats and foam suppression, it is 1 or more, preferably 3 or less, and more preferably 2 or less. In this invention, the number of branched carbon atoms is the sum of the number of tertiary and quaternary carbon atoms in the chain-type branched hydrocarbon group.

[0023] R 1a , R 2a A preferred embodiment is R 1a , R 2a The total number of carbon atoms in each of the chain-type branched hydrocarbon groups is, independently, 9 or more and 11 or less, and the number of carbon atoms in each main chain is, independently, 6 or 7, and the number of carbon atoms in each side chain is, independently, 1 or more and 3 or less, and the number of side chains is, independently, 1.

[0024] R 1a , R 2a The specific branched alkyl groups may be the same or different, and branched alkyl groups selected from 2-propylheptyl groups and 3,5,5-trimethylhexyl groups are preferred.

[0025] In general formula (a1), A 1 , A 2 Each of these is an alkylene group having 2 or more carbon atoms and 4 or fewer carbon atoms, preferably 3 or fewer. In general formula (a1), x and y are the average number of moles added, and from the viewpoint of cleaning properties and foam suppression properties for solid fats, etc., they are independently 0 or more, and 6 or less, preferably 4 or less, more preferably 2 or less, and even more preferably 0. Furthermore, x+y is preferably 0 or greater, preferably 12 or less, more preferably 6 or less, even more preferably 3 or less, and even more preferably 0, from the viewpoint of cleaning properties such as solid fats and foam suppression.

[0026] In general formula (a1), M 1This is a hydrogen ion, or an inorganic cation such as a sodium ion, ammonium ion, potassium ion, or magnesium ion, or an organic cation such as a monoethanolammonium ion, diethanolammonium ion, triethanolammonium ion, or morpholinium ion, preferably an inorganic cation selected from sodium ions, ammonium ions, potassium ions, and magnesium ions.

[0027] In general formula (a1), R 1a , R 2a The method for preparing the same compound is not particularly limited, but for example, it can be produced by referring to the method described in U.S. Patent Publication No. 2,028,091, and R 1a , R 2a As a method for preparing asymmetric compounds with different properties, for example, they can be manufactured by referring to Japanese Patent Publication No. 58-24555. (a) As a raw material for component (a), an alcohol with a predetermined number of carbon atoms to which an alkylene oxide has been added can also be used. Suitable alcohols used in the production of component (a) of the present invention include: (1) Primary alcohols such as 3,5,5-trimethylhexane-1-ol and 2-propylheptan-1-ol, (2) Secondary alcohols, such as 5-nonanol and 2,6-dimethyl-4-heptanol These are some examples.

[0028] The liquid detergent composition for dishwashers of the present invention may contain component (a) in amounts of, for example, 0.01% by mass or more, further 0.05% by mass or more, further 0.1% by mass or more, from the viewpoint of cleaning performance, and 10% by mass or less, further 5% by mass or less, further 3% by mass or less, and further 1% by mass or less, from the viewpoint of foaming properties. In this invention, the description of the amount of component (a) (such as mass%) refers to the mass of the compound converted to a sodium salt, for example, M in the general formula (a1) above. 1 This is based on the mass assuming that it is sodium.

[0029] (b) The component is a thickening agent [excluding thickening agents consisting of polymers containing acrylic acid as monomer units].

[0030] Examples of thickeners (b) include water-soluble polymer thickeners and thickeners selected from hydrogenated castor oil.

[0031] A water-soluble polymer thickener is a polymer compound that dissolves at least 1 g in 100 g of water at 25°C, and has a viscosity of 1% by mass of aqueous solution (Type B viscometer, rotor No. 3, 60 rpm, measurement time 1 minute, liquid temperature 25°C) of 100 mPa·s or more. The viscosity of the water-soluble polymer thickener is preferably 500 mPa·s or more, preferably 100,000 mPa·s or less, and more preferably 50,000 mPa·s or less.

[0032] Examples of water-soluble polymeric thickeners include polysaccharides, cellulose derivatives, and synthetic water-soluble polymers. Polysaccharides and cellulose derivatives are preferred as water-soluble polymeric thickeners, with polysaccharides being more preferred.

[0033] Examples of thickening polysaccharides include karaya gum, tragacanth gum, gum arabic, acemannan, konjac mannan, acacia gum, guatti gum, guar gum, locust bean gum, carrageenan, xanthan gum, gellan gum, pullulan, dextran, casein, gelatin, keratin, glutelin, glucagon, gluten, zein, and shellac. Among these, thickening polysaccharides selected from carrageenan, xanthan gum, guar gum, and gellan gum are preferred, and thickening polysaccharides selected from xanthan gum and guar gum are preferred.

[0034] Examples of cellulose derivatives include hydroxypropyl methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, methylcellulose, hydroxypropylcellulose, ethylcellulose, carboxymethylcellulose, cellulose phthalate acetate, nitrocellulose, and other cellulose ethers / esters. Among these, cellulose derivatives selected from hydroxypropyl methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, methylcellulose, hydroxypropylcellulose, ethylcellulose, and carboxymethylcellulose are preferred.

[0035] Examples of synthetic water-soluble polymers include polyvinyl alcohol, polyvinylpyrrolidone, polyalkylene oxide, polyacrylamide, polymethylacrylamide, polydimethylmethacrylamide, polyurethane, polyvinyl acetate, polyester, polyamide, polyamine, polyethyleneimine, copolymer of vinylpyrrolidone and vinyl acetate, and copolymer of vinylpyrrolidone and caprolactam.

[0036] The water-soluble polymer is preferably selected from carrageenan, xanthan gum, guar gum, gellan gum, hydroxypropyl methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, methylcellulose, hydroxypropylcellulose, ethylcellulose, and carboxymethylcellulose; more preferably selected from carrageenan, xanthan gum, guar gum, and gellan gum; even more preferably selected from xanthan gum and guar gum; and even more preferably xanthan gum.

[0037] Furthermore, hydrogenated castor oil can be used as the hydrogenated castor oil. Also, considering the control of solubility in water during composition preparation, hydrogenated castor oil with polyoxyalkylene added, preferably hydrogenated castor oil with polyoxyethylene added, can be used. The average number of moles of oxyalkylene, preferably oxyethylene, added to the hydrogenated castor oil with polyoxyalkylene added is, for example, 5 to 150, preferably 5 to 100. The iodine value of the hydrogenated castor oil (hydrogenated castor oil) is preferably, for example, 0.1 or more, more preferably 1 or more, and 70 or less, and more preferably 50 or less (gI2 / 100g, German Unified Method (German Einheitsmethode) DGF C-V11a(53)). In addition, in the present invention, hydrogenated castor oil may be incorporated into the composition as a mixture containing hydrogenated castor oil and other components. Examples of such mixtures include a mixture containing hydrogenated castor oil, an anionic surfactant, and water, and more specifically, a mixture 2 used when producing a liquid detergent composition by the method described in Japanese Patent Application Publication No. 2016-147935.

[0038] (b) The component is preferably a water-soluble polymer thickener, a thickening polysaccharide, a thickening polysaccharide selected from carrageenan, xanthan gum, guar gum, gellan gum, a thickening polysaccharide selected from xanthan gum and guar gum, and a thickening polysaccharide even more preferably from xanthan gum.

[0039] The liquid detergent composition for dishwashers of the present invention may contain component (b) in amounts of, for example, 0.01% by mass or more, further 0.05% by mass or more, further 0.1% by mass or more, and 2% by mass or less, further 1% by mass or less, and further 0.8% by mass or less.

[0040] In the liquid detergent composition for dishwashers of the present invention, from the viewpoint of cleaning power and finish, the mass ratio (a) / (b) of the content of component (a) to the content of component (b) is preferably 0.1 or more, more preferably 0.3 or more, even more preferably 0.5 or more, even more preferably 0.7 or more, and preferably 10 or less, more preferably 7 or less, even more preferably 5 or less, even more preferably 4 or less, even more preferably 3.5 or less, and even more preferably 3 or less.

[0041] The liquid detergent composition for dishwashers of the present invention may contain surfactants other than component (a) [hereinafter referred to as component (c)]. However, some components (c) exhibit foaming properties and may impair cleaning performance, so caution is required when using them. Surfactants having hydrocarbon groups with 14 or more carbon atoms, such as alkyl groups [hereinafter referred to as component (c1)], may reduce the emulsifying power of component (a) and decrease its cleaning power due to foaming properties. For example, nonionic surfactants having long-chain alkyl groups are themselves oily components and may impair the emulsifying power of component (a), so caution is necessary. Furthermore, amine compounds acting as surfactants may form complexes with component (a), potentially reducing the effectiveness of component (a). In particular, amine compounds having hydrocarbon groups with 12 or more carbon atoms, such as alkyl groups [hereinafter referred to as component (c2)] may reduce the emulsifying power of component (a), so caution is required when using them. The liquid detergent composition for dishwashers of the present invention contains, more preferably, 0.6% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, even more preferably 0.01% by mass or less, and 0% by mass or more, and may contain 0% by mass, i.e., no components (c1) or (c2) are present.

[0042] In the present invention, when using component (c), a surfactant with a small number of carbon atoms in the hydrocarbon group that is the hydrophobic group is preferred. For example, as component (c), a surfactant selected from anionic surfactants having hydrocarbon groups with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms [excluding component (a)], and nonionic surfactants having hydrocarbon groups with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms [hereinafter referred to as component (c3)] can be used. Examples of hydrocarbon groups in component (c3) include alkyl groups and alkenyl groups. (c3) Specifically, the components include anionic surfactants selected from alkanesulfonic acids having 8 to 12 carbon atoms, preferably 8 to 10; alkyl sulfate esters having 8 to 12 carbon atoms, preferably 8 to 10; polyoxyalkylene alkyl ether sulfate esters having an alkyl group having 8 to 12 carbon atoms, preferably 8 to 10; and salts thereof; alkyl glycosides having an alkyl group having 8 to 12 carbon atoms, preferably 8 to 10; alkyl glyceryl ethers having an alkyl group having 8 to 12 carbon atoms, preferably 8 to 10; and nonionic surfactants selected from polyoxyalkylene alkyl ethers having an alkyl group having 8 to 12 carbon atoms, preferably 8 to 10, and an average addition mole number of 3 to 20, preferably 3 to 10, and an oxyalkylene group, preferably an oxyethylene group. The (c3) component is preferably an anionic surfactant selected from alkanesulfonic acids having 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; alkyl sulfates having 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; polyoxyalkylene alkyl ether sulfates having an alkyl group having 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; and salts thereof [hereinafter referred to as (c3-1) component]. The polyoxyalkylene alkyl ether sulfate may have an average number of added moles of 0.1 to 5, preferably 0.5 to 2 oxyalkylene groups, preferably oxyethylene groups. The (c3-1) component preferably has one or more groups selected from decyl groups and dodecyl groups, and more preferably has a decyl group. The (c3-1) component preferably has 10 or 12 carbon atoms in the alkyl or alkane portion, and more preferably 10 carbon atoms.

[0043] The liquid detergent composition for dishwashers of the present invention preferably contains, from the viewpoint of enhancing cleaning power against complex stains including oils and proteins and obtaining excellent finish even under harsher conditions where such complex stains exist, an anionic surfactant having a hydrocarbon group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms, as component (c3), and further, one or more anionic surfactants selected from alkyl sulfate ester salts having an alkyl group with 10 to 12 carbon atoms and alkane sulfonates in which the alkane portion has 10 to 12 carbon atoms, as component (c3-1). The liquid dishwasher detergent composition of the present invention, which contains an anionic surfactant having a hydrocarbon group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms, as component (c), and further contains component (c3-1), exhibits excellent cleaning power against complex stains containing oil and protein adhering to dishes, and also provides excellent finish after rinsing even in the presence of such complex stains. It is presumed that by using component (a) and the anionic surfactant, for example component (c3-1), in combination, the anionic surfactant acts on the protein-backed film to promote the action of component (a) on complex stains containing protein, thereby exhibiting a cleaning effect against these complex stains, and consequently obtaining excellent finish even in the presence of such complex stains. However, the manifestation of the effects of the liquid dishwasher detergent composition of the present invention is not limited to this mechanism of action.

[0044] If the liquid detergent composition for dishwashers of the present invention contains component (c3), the composition may contain component (c3) in amounts of, for example, 0.01% by mass or more, further 0.05% by mass or more, further 0.1% by mass or more, and 15% by mass or less, further 10% by mass or less, and further 8% by mass or less. Also, if the liquid detergent composition for dishwashers of the present invention contains component (c3-1) as component (c), the content of component (c3-1) in the composition can also be selected from this range.

[0045] Dishwasher detergents sometimes use polymers containing acrylic acid as monomer units [hereinafter referred to as component (d)] as a dispersant. Component (d) is excluded from the thickener of component (b). The liquid dishwasher detergent composition of the present invention may also contain component (d), but care must be taken with its content in terms of finish quality. In the present invention, even if the amount of polymer component (d) is small or not present, a high level of cleaning power against oil stains can be obtained due to the action of component (a), and by including or omitting component (d), excellent finish quality is also achieved for articles with hydrophobic surfaces. (d) The component may be a polymer containing 30 mol% or more of acrylic acid, and further 50 mol% or more, of the total constituent monomers. (d) Examples of component (d) include polyacrylic acid or its salts, and acrylic acid-maleic acid copolymer. The weight-average molecular weight of component (d) is, for example, 1,000 or more, more specifically 2,000 or more, and 70,000 or less, and more specifically 50,000 or less. If the weight-average molecular weight of component (d) is less than 1,000, the expected effects such as scale suppression cannot be obtained, and if it exceeds 50,000, it is undesirable in terms of storage stability. The weight-average molecular weight of component (d) was measured by gel permeation chromatography (GPC) using polyethylene glycol of known molecular weight as a standard substance. (d) If the component is a salt, the salt may be part or all of it, and the salt is preferably an alkali metal salt, and more preferably a sodium salt or a potassium salt. The liquid detergent composition for dishwashers of the present invention optionally contains component (d), and the content of component (d) may be, for example, 5% by mass or less, further 3% by mass or less, further 1% by mass or less, and 0% by mass or more in the composition. Alternatively, the content of component (d) may be 0% by mass.

[0046] The liquid detergent composition for dishwashers of the present invention preferably contains a chelating agent as component (e). Examples of component (e) include (e1) hydroxypolycarboxylic acids or salts thereof such as citric acid, malic acid, tartaric acid, succinic acid [hereinafter referred to as component (e1)], (e2) aminocarboxylic acids or salts thereof such as methylglycine diacetic acid, glutamic acid diacetic acid, hydroxyethyliminodiacetic acid, ethylenediamine disuccinic acid, nitrilotriacetic acid, 1,3-propanediamine triacetic acid, 1,3-diamino-2-hydroxypropanetetraacetic acid, glycol etherdiaminetetraacetic acid, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraaminehexaacetic acid, dihydroxyethylglycine, hydroxyethylethylenediaminedicarboxymethylglutamic acid [hereinafter referred to as component (e2)], and (e3) condensed phosphoric acid such as tripolyphosphate or salts thereof. These components (e) may be used alone or in combination of two or more. Component (e2) is preferably an aminopolycarboxylic acid or a salt thereof. Note that component (e2) is excluded from component (e1).

[0047] (e) Among these, citric acid, malic acid, methylglycine diacetic acid, glutamate diacetic acid, ethylenediaminetetraacetic acid, tripolyphosphate, and salts thereof are preferred as chelating agents.

[0048] The liquid detergent composition for dishwashers of the present invention preferably contains component (e1) and component (e2) as component (e) from the viewpoint of enhancing the cleaning power of pigment stains such as tea stains. In that case, the mass ratio (e1) / (e2), which is the amount of component (e1) to the amount of component (e2), is preferably 0.1 or more, more preferably 1 or more, and 10 or less. The liquid detergent composition for dishwashers of the present invention preferably contains, as component (e), a hydroxypolycarboxylic acid selected from citric acid and malic acid or a salt thereof, and an aminopolycarboxylic acid selected from methylglycine diacetic acid, glutamic acid diacetic acid, and ethylenediaminetetraacetic acid or a salt thereof.

[0049] The liquid detergent composition for dishwashers of the present invention contains component (e) in an amount of preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 1% by mass or more, and even more preferably 3% by mass, from the viewpoint of cleaning performance, and preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less, from the viewpoint of formulation stability.

[0050] In the present invention, it is preferable to include an antifoaming agent as component (f) from the viewpoint of foam suppression. (f) From the viewpoint of suitability for formulation, one or more components selected from polyalkylene glycols using alkylene oxides with 3 or 4 carbon atoms as monomer units, and silicone compounds are preferred. These can also be used in combination.

[0051] (f) Examples of polyalkylene glycols that use a C3 or C4 alkylene oxide as a monomer unit include polypropylene glycol and polybutylene glycol, with polypropylene glycol being preferred. The number-average molecular weight of polyalkylene glycols, which use alkylene oxides with 3 or 4 carbon atoms as monomer units, is preferably 1,000 or more, more preferably 1,500 or more, even more preferably 2,000 or more, and preferably 20,000 or less, more preferably 10,000 or less, even more preferably 6,000 or less, and even more preferably 4,000 or less, from the viewpoint of suppressing foaming during use. The number-average molecular weight can be determined from the hydroxyl value. The hydroxyl value can be measured by a method in accordance with JIS K-1557-1.

[0052] The silicone compound of component (f) is not particularly limited and can be in oil, solution, powder, or emulsion form, but examples include polyorganosiloxane oil such as polydimethylsiloxane, dispersions of polyorganosiloxane resins, polyorganosiloxane emulsions, and combinations of polyorganosiloxane and silica particles in which polyorganosiloxane is chemically adsorbed or melted onto silica. Among these, polydimethylsiloxane can be cited as component (f).

[0053] The liquid detergent composition for dishwashers of the present invention contains component (f) in an amount of preferably 0.1% by mass or more, more preferably 0.15% by mass or more, from the viewpoint of defoaming or anti-foaming properties, and preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less, from the viewpoint of storage stability.

[0054] The dishwasher detergent composition of the present invention may further contain optional components such as solvents, hydrotropes, alkaline agents, pH adjusters, viscosity modifiers, fragrances, colorants, antioxidants, preservatives, antifoaming agents, bleaching agents, bleaching activators, rust inhibitors, and enzymes.

[0055] The liquid detergent composition for dishwashers of the present invention contains water. The water content may be, for example, 50% by mass or more, more specifically 70% by mass or more, and 95% by mass or less, and more specifically 90% by mass or less, in the composition.

[0056] The liquid detergent composition for dishwashers of the present invention has a pH at 25°C that is preferably 2 or higher, more preferably 4 or higher, even more preferably 5 or higher, and preferably 10 or lower, more preferably 9 or lower, and even more preferably 8 or lower, from the viewpoint of minimizing irritation to the hands. The pH can be measured by the glass electrode method.

[0057] The liquid detergent composition for dishwashers of the present invention has a viscosity at 25°C that, depending on the application, is preferably 3 mPa·s or more, more preferably 10 mPa·s or more, and preferably 5,000 mPa·s or less, and more preferably 2,500 mPa·s or less. The viscosity can be adjusted using commonly used thickeners, solvents, hydrotropes, etc. The viscosity of the liquid detergent composition for dishwashers of the present invention can be measured using a B-type viscometer under the conditions of rotor No. 2, 6 rpm, measurement time 1 minute, and liquid temperature 25°C.

[0058] The liquid detergent composition for dishwashers of the present invention is preferably used by preparing a cleaning solution by diluting the composition with water, for example, 10 to less than 10,000 times, and further 50 to less than 5,000 times, and then using the solution for cleaning.

[0059] From the viewpoint of cleaning power, the dishwasher detergent composition of the present invention has a pH at 25°C of a 0.2% by mass aqueous dilution (corresponding to a 500-fold dilution) that is preferably 5 or higher, more preferably 5.5 or higher, even more preferably 6 or higher, and preferably 11 or lower, more preferably 10 or lower, and even more preferably 9 or lower. The pH can be measured by the glass electrode method.

[0060] The washing temperature when using the liquid detergent composition for dishwashers of the present invention is not particularly limited, but from the viewpoint of cleaning power and re-adhesion prevention based on dirt dispersion power, it can be selected from, for example, 10°C or higher, more preferably 20°C or higher, 100°C or lower, more preferably 90°C or lower, and more preferably 60°C or lower. When using the liquid detergent composition for dishwashers of the present invention in a dishwasher, for example a commercially available dishwasher, the washing temperature is preferably 40°C or higher, more preferably 55°C or higher, more preferably 90°C or lower, and more preferably 80°C or lower. Also, when using the liquid detergent composition for dishwashers of the present invention in a dishwasher, for example a commercially available dishwasher, the rinsing temperature is preferably 50°C or higher, more preferably 65°C or higher, more preferably 90°C or lower, and more preferably 80°C or lower.

[0061] The hardness of the water used to dilute the liquid detergent composition for dishwashers of the present invention is preferably 0°DH or higher, more preferably 2°DH or higher, and preferably 20°DH or lower, more preferably 10°DH or lower, and even more preferably 8°DH or lower, in German hardness units.

[0062] The liquid detergent composition for dishwashers of the present invention is used for washing dishes in a dishwasher. Examples of dishes include items used to hold food, such as plates, bowls, and cups, and items used for serving food, such as chopsticks, forks, knives, and spoons. In this invention, "dishes" may also include, in addition to these items, storage containers such as Tupperware and jars, cooking utensils such as knives, cutting boards, pots, frying pans, and fish grills, and cooking appliances such as food processors and mixers, as well as items and their parts that come into contact with food and are washable in a dishwasher. Examples of dish materials include plastic (including silicone resin), metal, ceramic, wood, and combinations thereof. The liquid detergent composition for dishwashers of the present invention is suitably used for washing dishes with hydrophobic surfaces, such as plastic dishes. Washing using the liquid detergent composition for dishwashers of the present invention is similar to washing in a normal dishwasher.

[0063] The present invention provides a method for washing dishes (hereinafter also referred to as the "washing method of the present invention") in which dishes are washed in a dishwasher using a washing solution containing the dishwasher liquid detergent composition of the present invention and water. The washing method of the present invention may be a method for washing dishes using a washing solution containing component (a), component (b), and water. The washing solution may be obtained by diluting the dishwasher liquid detergent composition of the present invention with water, for example, by diluting it with water at a ratio of 10 to 10,000 times. The washing solution may be obtained by mixing the dishwasher liquid detergent composition of the present invention with water having the German hardness.

[0064] The concentration of component (a) in the washing solution may be, for example, 1 ppm or more, 3 ppm or more, 5 ppm or more, and 1000 ppm or less, 500 ppm or less, and 100 ppm or less.

[0065] The concentration of component (b) in the washing solution may be, for example, 1 ppm or more, 2 ppm or more, 5 ppm or more, and 500 ppm or less, 100 ppm or less, and 50 ppm or less.

[0066] The cleaning solution preferably contains component (c3) and component (c3-1). The concentration of component (c3) in the cleaning solution may be, for example, 10 ppm or more, more preferably 20 ppm or more, more preferably 30 ppm or more, and 2000 ppm or less, more preferably 1000 ppm or less, and more preferably 500 ppm or less. Also, if the cleaning solution contains component (c3-1) as component (c), the concentration of component (c3-1) in the cleaning solution can also be selected from this range.

[0067] From the viewpoint of cleaning power, the cleaning solution preferably has a pH of 5 or higher, more preferably 5.5 or higher, even more preferably 6 or higher, and preferably 11 or lower, more preferably 10 or lower, and even more preferably 9 or lower. The pH can be measured by the glass electrode method. The pH of the cleaning solution is the pH at the temperature during cleaning, but it may also be the pH at 25°C.

[0068] The cleaning solution has a temperature of preferably 40°C or higher, more preferably 55°C or higher, and preferably 90°C or lower, more preferably 80°C or lower.

[0069] Furthermore, in the cleaning method of the present invention, rinsing with water can be performed after cleaning with the cleaning solution. The water used for rinsing has a temperature of preferably 50°C or higher, more preferably 65°C or higher, and preferably 90°C or lower, and more preferably 80°C or lower.

[0070] In the cleaning method of the present invention, the dishes may be dishes that have dirt, including oil stains, attached to them. The cleaning method of the present invention can suppress the re-adhesion of dirt to tableware, such as tableware having a hydrophobic surface.

[0071] <Aspects of the Invention> The following are examples of embodiments of the present invention. The matters described in the description of the liquid detergent composition for dishwashers and the method for cleaning hard articles of the present invention can be appropriately applied to these embodiments.

[0072] <1> A liquid detergent composition for dishwashers, comprising (a) a branched alkyl sulfosuccinate having 9 to 11 carbon atoms [hereinafter referred to as component (a)], (b) a thickener [excluding thickeners consisting of polymers containing acrylic acid as monomer units] [hereinafter referred to as component (b)], and water.

[0073] <2> (a) The branched alkyl group of component is a branched alkyl group having a main chain with 6 or 7 carbon atoms and one or more side chains, with a total of 3 carbon atoms in the side chains. <1> A liquid detergent composition for dishwashers as described above.

[0074] <3> (a) The branched alkyl group of component is a branched alkyl group selected from a 2-propylheptyl group and a 3,5,5-trimethylhexyl group. <1> or <2> A liquid detergent composition for dishwashers as described above.

[0075] <4> (a) The component is a branched sulfosuccinate ester represented by the following general formula (a1): <1> ~ <3> A liquid detergent composition for dishwashers as described in any of the above.

[0076] [ka]

[0077] [In the formula, R 1a , R 2a Each of these is independently a branched alkyl group having 9 to 11 carbon atoms. 1 , A 2 Each of these is an alkylene group with 2 to 4 carbon atoms, and x and y are the average number of added moles, each independently between 0 and 6. 1 [This is a hydrogen atom or a cation.]

[0078] <5> In general formula (a1), R 1a , R 2a The number of side chains is 1 or more, preferably 3 or less, and more preferably 2 or less. <4> A liquid detergent composition for dishwashers as described above.

[0079] <6> In general formula (a1), R 1a , R 2a The number of branched carbon atoms is 1 or more, preferably 3 or less, and more preferably 2 or less. <4> or <5> A liquid detergent composition for dishwashers as described above.

[0080] <7> In general formula (a1), R 1a , R 2a The total number of carbon atoms in each branched hydrocarbon chain is independently 9 or 10, the number of carbon atoms in the main chain is independently 6 or 7, the number of carbon atoms in each side chain is independently 1 or more and 3 or less, and the number of side chains is independently 1. <4> ~ <6> A liquid detergent composition for dishwashers as described in any of the above.

[0081] <8> In general formula (a1), R 1a , R 2a However, these are branched alkyl groups selected from 2-propylheptyl group and 3,5,5-trimethylhexyl group, respectively. <4> ~ <7> A liquid detergent composition for dishwashers as described in any of the above.

[0082] <9> In the general formula (a1), x and y are each independently 0. <4> ~ <8> A liquid detergent composition for dishwashers as described in any of the above.

[0083] <10> In general formula (a1), M 1 However, it is an inorganic cation selected from sodium ions, ammonium ions, potassium ions, and magnesium ions. <4> ~ <9> A liquid detergent composition for dishwashers as described in any of the above.

[0084] <11> (a) The component is a branched alkyl sulfosuccinate diester in which each of the two branched alkyl groups has 9 to 11 carbon atoms. <1> ~ <10> A liquid detergent composition for dishwashers as described in any of the above.

[0085] <12> (a) The component is contained in amounts of 0.01% by mass or more, further 0.05% by mass or more, further 0.1% by mass or more, and 10% by mass or less, further 5% by mass or less, further 3% by mass or less, and further 1% by mass or less. <1> ~ <11> A liquid detergent composition for dishwashers as described in any of the above.

[0086] <13> (b) The component is a thickener selected from water-soluble polymer thickeners and hydrogenated castor oil. <1> ~ <12> A liquid detergent composition for dishwashers as described in any of the above.

[0087] <14> The water-soluble polymer thickener is a water-soluble polymer selected from thickening polysaccharides, cellulose derivatives, and synthetic water-soluble polymers. <13> A liquid detergent composition for dishwashers as described above.

[0088] <15> The thickening polysaccharide is selected from carrageenan, xanthan gum, guar gum, and gellan gum, and further selected from xanthan gum and guar gum. <14> A liquid detergent composition for dishwashers as described above.

[0089] <16> The cellulose derivative is a cellulose derivative selected from hydroxypropyl methylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, methylcellulose, hydroxypropylcellulose, ethylcellulose, and carboxymethylcellulose. <14> or <15> A liquid detergent composition for dishwashers as described above.

[0090] <17> The synthetic water-soluble polymer is selected from polyvinyl alcohol, polyvinylpyrrolidone, polyalkylene oxide, polyacrylamide, polymethylacrylamide, polydimethylmethacrylamide, polyurethane, polyvinyl acetate, polyester, polyamide, polyamine, polyethyleneimine, copolymer of vinylpyrrolidone and vinyl acetate, and copolymer of vinylpyrrolidone and caprolactam. <14> ~ <16> A liquid detergent composition for dishwashers as described in any of the above.

[0091] <18> Hydrogenated castor oil is castor oil to which polyoxyethylene has been added. <13> ~ <17> A liquid detergent composition for dishwashers as described in any of the above.

[0092] <19> (b) The component is a water-soluble polymer thickener, further a thickening polysaccharide, further a thickening polysaccharide selected from carrageenan, xanthan gum, guar gum, and gellan gum, further a thickening polysaccharide selected from xanthan gum and guar gum, further xanthan gum, <13> ~ <18> A liquid detergent composition for dishwashers as described in any of the above.

[0093] <20> (b) The component is contained in an amount of 0.01% by mass or more, further 0.05% by mass or more, further 0.1% by mass or more, and 2% by mass or less, further 1% by mass or less, and further 0.8% by mass or less. <1> ~ <19> A liquid detergent composition for dishwashers as described in any of the above.

[0094] <21> The total content of surfactants having 14 or more carbon atoms, such as alkyl groups, and amine compounds having 12 or more carbon atoms, such as alkyl groups, and the total content of nonionic surfactants having 14 or more carbon atoms, such as alkyl groups, and amine compounds having 12 or more carbon atoms, such as alkyl groups, in the composition is preferably 1% by mass or less, more preferably 0.6% by mass or less, even more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, even more preferably 0.01% by mass or less, and 0% by mass or more, or 0% by mass. <1> ~ <20> A liquid detergent composition for dishwashers as described above.

[0095] <22> The product contains a surfactant selected from an anionic surfactant having a hydrocarbon group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms [excluding component (a)], and a nonionic surfactant having a hydrocarbon group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms [hereinafter referred to as component (c3)]. <1> ~ <21> A liquid detergent composition for dishwashers as described in any of the above.

[0096] <23> The anionic surfactant of component (c3) is an anionic surfactant selected from alkanesulfonic acid having 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; alkyl sulfate ester having 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; polyoxyalkylene alkyl ether sulfate ester having an alkyl group, preferably 8 to 10 carbon atoms; and salts thereof [hereinafter referred to as component (c3-1)]. <22> A liquid detergent composition for dishwashers as described above.

[0097] <24> (c3-1) Component has one or more groups selected from a decyl group and a dodecyl group, and further has a decyl group, <23> A liquid detergent composition for dishwashers as described above.

[0098] <25> The nonionic surfactant of component (c3) is a nonionic surfactant selected from alkyl glycosides having an alkyl group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; alkyl glyceryl ethers having an alkyl group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms; and polyoxyalkylene alkyl ethers having an alkyl group with 8 to 12 carbon atoms, preferably 8 to 10 carbon atoms, and an oxyalkylene group with an average addition mole number of 3 to 20, preferably 3 to 10 carbon atoms, preferably an oxyethylene group. <22> ~ <24> A liquid detergent composition for dishwashers as described in any of the above.

[0099] <26> (c3) The product contains 0.01% by mass or more, then 0.05% by mass or more, then 0.1% by mass or more, and then 15% by mass or less, then 10% by mass or less, and then 8% by mass or less. <22> ~ <25> A liquid detergent composition for dishwashers as described in any of the above.

[0100] <27> The composition contains a polymer with acrylic acid as a monomer unit at a concentration of 5% by mass or less, further at 3% by mass or less, further at 1% by mass or less, and 0% by mass or more. <1> ~ <26> A liquid detergent composition for dishwashers as described in any of the above.

[0101] <28> (e) contains a chelating agent as component, further comprising (e1) a hydroxypolycarboxylic acid or a salt thereof [hereinafter referred to as component (e1)], (e2) an aminocarboxylic acid or a salt thereof [hereinafter referred to as component (e2)], and (e3) a chelating agent selected from condensed phosphoric acid or a salt thereof, and further comprising a chelating agent selected from citric acid, malic acid, methylglycine diacetic acid, glutamic acid diacetic acid, ethylenediaminetetraacetic acid, tripolyphosphate, and salts thereof. <1> ~ <27> A liquid detergent composition for dishwashers as described in any of the above.

[0102] <29> (e) The product contains component (e1) and component (e2) as components, and the mass ratio of the content of component (e1) to the content of component (e2), (e1) / (e2), is 0.1 or more, more than 1, and less than or equal to 10. <28> A liquid detergent composition for dishwashers as described above.

[0103] <30> (e) The product contains component (e) preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 1% by mass or more, even more preferably 3% by mass, and preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 10% by mass or less. <29> or <28> A liquid detergent composition for dishwashers as described above.

[0104] <31> (f) The component contains an antifoaming agent, and further contains one or more selected from polyalkylene glycols with C3 or C4 alkylene oxides as monomer units, and silicone compounds. <1> ~ <30> A liquid detergent composition for dishwashers as described in any of the above.

[0105] <32> (f) The polyalkylene glycol of component (f) is polypropylene glycol, and more preferably has a number average molecular weight of 1,000 or more, more preferably 1,500 or more, even more preferably 2,000 or more, and more preferably 20,000 or less, more preferably 10,000 or less, even more preferably 6,000 or less, and even more preferably 4,000 or less. <31> A liquid detergent composition for dishwashers as described above.

[0106] <33> (f) The silicone compound of component (f) is selected from polyorganosiloxane oil, dispersion of polyorganosiloxane resin, polyorganosiloxane emulsion, and combinations of polyorganosiloxane and silica particles in which polyorganosiloxane is chemically adsorbed or melted on silica. <31> or <32> A liquid detergent composition for dishwashers as described above.

[0107] <34> (f) The product contains component (f) preferably 0.1% by mass or more, more preferably 0.15% by mass or more, preferably 5% by mass or less, more preferably 4% by mass or less, and even more preferably 3% by mass or less. <31> ~ <33> A liquid detergent composition for dishwashers as described in any of the above.

[0108] <35> The pH of the liquid detergent composition for dishwashers at 25°C is preferably 2 or higher, more preferably 4 or higher, even more preferably 5 or higher, and preferably 10 or lower, more preferably 9 or lower, and even more preferably 8 or lower. <1> ~ <34> A liquid detergent composition for dishwashers as described in any of the above.

[0109] <36> The viscosity of the liquid detergent composition for dishwashers at 25°C is preferably 3 mPa·s or more, more preferably 10 mPa·s or more, and preferably 5,000 mPa·s or less, more preferably 2,500 mPa·s or less. <1> ~ <35> A liquid detergent composition for dishwashers as described in any of the above.

[0110] <37> The mass ratio (a) / (b), which is the content of component (a) to the content of component (b), is preferably 0.1 or more, more preferably 0.3 or more, even more preferably 0.5 or more, even more preferably 0.7 or more, and preferably 10 or less, more preferably 7 or less, even more preferably 5 or less, even more preferably 4 or less, even more preferably 3.5 or less, and even more preferably 3 or less. <1> ~ <36> A liquid detergent composition for dishwashers as described in any of the above.

[0111] <38> In the dishwasher, <1> ~ <37> A method for washing dishes, comprising washing dishes using a washing solution containing a dishwasher liquid detergent composition and water as described in any of the above.

[0112] <39> The concentration of component (a) in the washing solution is 1 ppm or more, further 3 ppm or more, further 5 ppm or more, and 1000 ppm or less, further 500 ppm or less, and further 100 ppm or less. <38> The cleaning method described above.

[0113] <40> The temperature of the cleaning solution is 40°C or higher, preferably 55°C or higher, and preferably 90°C or lower, more preferably 80°C or lower. <38> or <39> The cleaning method described above.

[0114] <41> The cleaning solution is prepared by diluting the dishwasher liquid detergent composition with water to a ratio of 10 to less than 10,000 times, and further to 50 to less than 5,000 times. <38> ~ <40> The cleaning method described in one of the following.

[0115] <42> The tableware includes items and parts thereof that come into contact with food and are washable in a dishwasher, and further includes items and parts thereof selected from plates, bowls, cups, chopsticks, forks, knives, spoons, Tupperware, bottles, kitchen knives, cutting boards, pots, frying pans, fish grills, food processors, and mixers. <38> ~ <41> The cleaning method described in one of the following.

[0116] <43> The tableware is made from one or more materials selected from plastic (including silicone resin), metal, ceramic, wood, and combinations thereof. <38> ~ <42> The cleaning method described in one of the following.

[0117] <44> The tableware is tableware with a hydrophobic surface. <38> ~ <43> The cleaning method described in one of the following. [Examples]

[0118] <Example 1 and Comparative Example 1> Using the liquid detergent compositions for dishwashers shown in Table 1, dishes were washed in an automatic dishwasher (S45VS6SD, Panasonic Corporation), and the oil stain removal performance and finish quality (I) were evaluated using the following methods. The results are shown in Table 1.

[0119] (1) Cleaning ability for oil stains Four polypropylene plates were placed inside an automatic dishwasher. Two of the plates were contaminated with a mixture of pork fat and rapeseed (1 / 1 by mass ratio), with 3g of each plate coated on them. The remaining two plates were uncontaminated. Six grams of the dishwasher liquid detergent composition shown in Table 1 were added, and the dishwasher was washed on a standard cycle. A total of three panelists touched the washed dishes and assigned evaluation scores according to the following criteria. The average scores, rounded to one decimal place, are shown in the table. Furthermore, the concentration of component (a) in the cleaning solution applied to tableware (a cleaning solution formed by diluting the liquid detergent composition with water) was 10 ppm when 6 g of the composition was added. *Evaluation criteria for oil stain removal performance 4: The dirt has been removed, and it feels pleasantly squeaky to the touch. 3: The dirt is gone, but it doesn't feel squeaky clean to the touch. 2: Most of the dirt appears to have been washed away, but streaks remain when rubbed with a finger. 1: You can see that there is still oil left.

[0120] (2) Finish quality (I) A clean, black polypropylene lunch box was placed inside the automatic dishwasher. Six grams of the liquid dishwasher detergent composition shown in Table 1 were added, and the dishwasher was washed on a standard cycle. After washing, three panelists evaluated the lunch boxes in comparison to unwashed lunch boxes according to the following criteria, and the average values, rounded to one decimal place, are shown in Table 1. Furthermore, the concentration of component (a) in the cleaning solution applied to tableware (a cleaning solution formed by diluting the liquid detergent composition with water) was 10 ppm when 6 g of the composition was added. 3: There are almost no white water spots or cloudiness remaining, and it is very clean. 2: White water spots and condensation remain on about half of the lunchbox. 1: White water spots and cloudiness remain on more than half of the lunchbox, which is clearly more frequent than level 2.

[0121] [Table 1]

[0122] *1 pH was adjusted with monoethanolamine. *2 Viscosity was measured using a B-type viscometer, stored at 25°C, with the rotor rotation speed set to 6 rpm, 1 minute after the start of rotation.

[0123] The components in Table 1 are as follows. Note that component (a') in Table 1 is also component (c), but for convenience it is shown as component (a') as it is used as a component to compare with component (a). In addition, the "+" next to an enzyme means that the composition contains 0.001% by mass of amylase (Duramyl120T (Novozymes)) as an enzyme protein and 0.001% by mass of protease (Savinase18T-B (Novozymes)) as an enzyme protein (the same applies below). • Xanthan gum: Manufactured by DSP Gokyo Food & Chemical Co., Ltd., Keldent, viscosity rating 1200-1700 mPa·s (viscosity rating measurement method is as follows) (Viscosity standard measurement method) The viscosity of an aqueous solution containing 1% by mass of xanthan gum (Keldent) and 1% by mass of KCl is measured at 25°C using a Brookfield viscometer with rotor No. 3 and 60 revolutions per minute. The measured value is multiplied by 20 to obtain the viscosity standard (mPa·s). This viscosity standard value is approximately the same as the viscosity value of a 1% by mass aqueous solution measured by the method described above.

[0124] • Hydrogenated castor oil mixture: In Japanese Patent Publication No. 2016-147935, <Example 1> and <Preparation of Mixture 2>, without performing <Optional Step A>, Mixture 2 was obtained through Steps 1 and 2 (a mixture of hydrogenated castor oil: 2.9%, sodium alkylbenzenesulfonate (component (c1)): 11.7%, and water: 85.4%). In the table, (a) / (b) was calculated based on the amount of hydrogenated castor oil. • Polyacrylic acid: Sumitomo Seika Co., Ltd. APKEC HV-701EDR (1% by mass aqueous solution viscosity (25℃) 10000 mPa·s or higher) • Polypropylene glycol: Number average molecular weight 3000

[0125] <Example 2> Using the liquid detergent compositions for dishwashers shown in Table 2, dishes were washed in an automatic dishwasher (S45VS6SD, manufactured by Panasonic). The cleaning performance for oil stains was evaluated using the same method as in Example 1, and the finish quality (II) was evaluated using the following method. The results are shown in Table 2. (1) Finish quality (II) (1-1) Method for preparing protein stains After making a sunny-side-up egg (with the yolk partially cooked) in a frying pan, I collected only the egg liquid using a sieve. (1-2) Evaluation Method Two clean glass cups were placed inside an automatic dishwasher. 2.5g of the egg mixture collected in (1-1), 2.5g of oil stains from a 1:1 ratio of pork fat to rapeseed oil, and 6g of the dishwasher detergent composition shown in the table were added, and the dishwasher was washed on a standard cycle. After washing, three panelists held the glass cups up to a light source (fluorescent lamp, AP Japan Co., Ltd., model number: 100V-4NSP, distance from the light source: 10cm) and observed them visually. They assigned evaluation points to each of the two cups according to the following criteria, and the average of the sum of all evaluation points was used as the evaluation result. The average value was rounded to the first decimal place and is shown in Table 2. Furthermore, the concentration of component (a) in the cleaning solution applied to tableware (a cleaning solution formed by diluting a dishwasher detergent composition with water) was 10 ppm when 6 g of the composition was added. 4: There are almost no water spots or clouds, and it is clean. 3: Water spots and / or clouding are present on less than a quarter of the entire cup, but this does not affect its usability and does not require rewashing. 2: Water spots and / or clouding are present on more than a quarter of the glass but less than half of it, requiring rewashing. 1: Water spots and / or clouding have occurred on more than half of the glass, requiring rewashing.

[0126] [Table 2]

[0127] *1 pH was adjusted with monoethanolamine.

[0128] The components listed in Table 2 are as follows: • Xanthan gum: Same as in Table 1 • Nonionic surfactant (1): Polyoxyethylene alkyl ether, in which an average of 3 moles of oxyethylene groups are added to a secondary higher alcohol with an alkyl group having 12 carbon atoms. • Polypropylene glycol: Same as in Table 1

[0129] <Combination example> Table 3 shows examples of the liquid detergent compositions for dishwashers of the present invention.

[0130] [Table 3]

[0131] *1 pH was adjusted with monoethanolamine.

[0132] The ingredients listed in the table are as follows: • Xanthan gum: Same as in Table 1 Guar gum: Fujifilm Wako Pure Chemical Industries, Ltd. (Viscosity of 1% by mass aqueous solution (25℃): 3000-5000 mPa.s) • Hydroxyethylcellulose: Daicel Corporation HEC Daicel EE820 • Polyvinyl alcohol: Kuraray Co., Ltd., Kuraray Poval 22-88 • Nonionic surfactant (1): Same as in Table 2 • Polyacrylic acid / maleic acid copolymer: weight-average molecular weight 21,000, acrylic acid / maleic acid = 71 / 29 (molar ratio) (viscosity of 1% aqueous solution (25°C) is 50 mPa·s or less) • Polypropylene glycol: Same as in Table 1 • Silicone compound: Emulsion-type silicone KM-72 manufactured by Shin-Etsu Chemical Co., Ltd.

Claims

1. A liquid detergent composition for dishwashers comprising: (a) a branched alkyl sulfosuccinate having 9 to 11 carbon atoms [hereinafter referred to as component (a)]; (b) a thickener selected from water-soluble polymer thickeners and hydrogenated castor oil [excluding thickeners consisting of polymers containing acrylic acid as monomer units] [hereinafter referred to as component (b)]; an anionic surfactant selected from alkanesulfonic acid having 8 to 12 carbon atoms, alkyl sulfate ester having 8 to 12 carbon atoms, polyoxyalkylene alkyl ether sulfate ester having an alkyl group having 8 to 12 carbon atoms, and salts thereof; and water.

2. The liquid detergent composition for dishwashers according to claim 1, wherein the content of a polymer containing acrylic acid as a monomer unit is 5% by mass or less in the composition.

3. (a) The liquid detergent composition for dishwashers according to claim 1, wherein the branched alkyl group of component (a) is a branched alkyl group having a main chain with 6 or 7 carbon atoms and one or more side chains, the total number of carbon atoms of the side chains being 3 or 4.

4. (a) The liquid detergent composition for dishwashers according to claim 1, wherein the branched alkyl group of component is a branched alkyl group selected from a 2-propylheptyl group and a 3,5,5-trimethylhexyl group.

5. The liquid detergent composition for dishwashers according to Claim 1, wherein the mass ratio (a) / (b), which is the mass ratio of the content of component (a) to the content of component (b), is 0.1 or more and 10 or less.

6. A method for washing dishes using a dishwasher, wherein the dishes are washed using a washing solution containing the dishwasher liquid detergent composition and water according to any one of claims 1 to 5.

7. The cleaning method according to claim 6, wherein the concentration of component (a) in the cleaning solution is 1 ppm or more and 1000 ppm or less.

8. The cleaning method according to claim 6, wherein the temperature of the cleaning solution is 40°C or higher.

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