JP6906097B1 - Concentrated liquid detergent composition for automatic dishwasher and method of washing dishes with automatic dishwasher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a concentrated liquid for an automatic dishwasher which exhibits excellent detergency even at a low concentration, has excellent corrosion resistance to copper alloys and aluminum, suppresses generation of silica scale, and exhibits good storage stability. A method for cleaning dishes by an automatic dishwasher using the detergent composition and the concentrated liquid detergent composition for an automatic dishwasher of the present invention is provided. SOLUTION: A concentrated liquid cleaning agent composition for an automatic dishwasher contains alkali metal silicate as a component (A) in an amount of 1% by mass or more and 8% by mass or less in terms of SiO2, and ethylenediamine tetraacetic acid or a component thereof as a component (B). Salt 1% by mass or more, 10% by mass or less, (C) component other than component (B) aminocarboxylic acid type chelating agent or salt thereof 5% by mass or more, 20% by mass or less, component (D) metal corrosion inhibitor It contains 0.01% by mass or more and 4.8% by mass or less, and water as the component (E), and the mass ratio of the component (B) to the component (C) is 0 in the value of (B) / (C). It is configured so that the total amount of sodium in the composition is 3.9% by mass or less, which is 1 or more and 0.9 or less, and the method of washing dishes by the automatic dishwasher is the above-mentioned automatic dishwasher. The concentrated liquid cleaning agent composition for use is diluted in the range of 0.01% by mass or more and 0.15% by mass or less, and the dishes and the like arranged in the washing machine are washed. [Selection diagram] None

Description

The present invention relates to a concentrated liquid detergent composition for an automatic dishwasher, particularly a concentrated liquid detergent composition for an automatic dishwasher suitable for a commercial automatic dishwasher. The present invention also relates to a method for washing tableware using the concentrated liquid detergent composition for an automatic dishwasher.

In recent years, automatic dishwashers have become widely used for washing dishes, and even in hotels, restaurants, food service companies, hospitals, company cafeterias, etc., in order to efficiently wash used dishes, In addition, due to the recent increase in hygiene awareness, commercial automatic dishwashers are widely used.

When washing dishes with an automatic dishwasher, especially a commercial automatic dishwasher, generally, the washing liquid prepared to a predetermined concentration is heated and held in the washing liquid tank, and then the washing liquid in the washing liquid tank is washed from the nozzle. After washing the dishes in the dishwasher by injecting a certain amount into the machine, the washing is performed through a process of injecting a certain amount of rinse water from the nozzle of the washing machine to rinse and dry. Conventionally, liquid, granular, powdery, and solid detergents have been used as cleaning agents for automatic dishwashers. The powdery, granular, or solid form (hereinafter, also referred to as solid form) has an advantage that the volume can be reduced at a high concentration. However, it is not easy for a solid-state cleaning agent containing a plurality of components to contain each component in a predetermined concentration range for each solid substance such as a solid substance, and the component concentration when dissolved to obtain a cleaning solution. Is likely to vary. Therefore, in recent years, the development of a concentrated liquid detergent composition that is liquid and can be reduced in volume at a high concentration has been progressing.

By the way, while the cleaning agent for commercial automatic dishwashers exerts high detergency by blending an alkaline agent, there is a concern about corrosion of easily corrosive metals such as copper and aluminum. For example, a gunmetal impeller is used for the circulation pump in the automatic dishwasher, and aluminum, pure copper, brass cookware and the like may be washed as the object to be washed. Therefore, the above-mentioned cleaning agent is required to have high detergency and low corrosiveness.

On the other hand, in order to solve the metal corrosiveness, as a conventional high-alkali detergent, a detergent composition for an automatic dishwasher containing an alkali agent, a phosphorus-free water-soluble metal ion sequestering agent, and a benzotriazole derivative ( Reference 1), detergent composition for automatic cleaning machine containing antifoaming agent and corrosion inhibitor (reference 2), detergent composition containing alkali, anticorrosive and chelating agent (reference 3), A concentrated liquid detergent composition for an automatic dishwasher containing an alkaline agent, a chelating agent, and a metal corrosion inhibitor (Reference 4) has been proposed.

Japanese Unexamined Patent Publication No. 2015-67833 JP-A-2017-214445 Japanese Unexamined Patent Publication No. 2016-98331 Japanese Unexamined Patent Publication No. 2020-50781

However, when the inventors of the present application examined the above-mentioned conventional detergent composition, it was found that there are problems below.
That is, the detergent compositions described in Patent Documents 1 and 2 show corrosion prevention properties against copper alloys by blending a corrosion inhibitor, but the corrosion prevention properties against aluminum are not sufficient, and silicates are used. When it was contained, it tended to be insufficient in storage stability. Since concentrated liquid detergents are used after being diluted, they tend to be stored for a long period of time after purchase. Therefore, it is desired to provide a concentrated liquid detergent that can be stably stored regardless of the storage environment.
The detergent composition described in Reference 3 exhibits corrosion resistance not only for copper alloys but also for aluminum, but it is difficult to remove it in an automatic dishwasher because it contains a large amount of silicate as an alkaline agent. A silica scale is formed. There were problems such as hygiene problems and nozzle clogging due to the silica scale adhering to the inside of the automatic dishwasher and the piping.
The detergent composition described in Cited Document 4 exhibits corrosion resistance to metals such as aluminum and copper, but the corrosion resistance of aluminum was not sufficient in actual use in an automatic dishwasher.

The present invention has been made in view of the above problems. That is, the present invention is an automatic dishwasher that exhibits excellent detergency even at low concentrations, is excellent in corrosion resistance to copper alloys and aluminum, suppresses the generation of silica scale, and exhibits good storage stability. It is an object of the present invention to provide a concentrated liquid detergent composition for use. Another object of the present invention is to provide a method for washing tableware by an automatic dishwasher using the concentrated liquid detergent composition for an automatic dishwasher.

As a result of diligent studies to solve the above problems, the present inventors have made a chelate containing an alkali metal silicate (component (A)) and a metal corrosion inhibitor (component (D)) in a predetermined range. As an agent, ethylenediaminetetraacetic acid or a salt thereof (component (B)) and an aminocarboxylic acid type chelating agent other than the above component (B) or a salt thereof (component (C)) are used in combination, and these components (B) and (component) If the composition is prepared with the ratio of C) component in a specific range, it exhibits excellent detergency even at a low concentration, is excellent in preventing metal corrosion against copper alloys, aluminum, etc., and generates silica scale. We have found that it is possible to provide a liquid cleaning agent that is suppressed and exhibits good storage stability, and has completed the present invention.

That is, in the concentrated liquid cleaning agent composition for an automatic dishwasher of the present invention, alkali metal silicate as a component (A) is 1% by mass or more and 8% by mass or less in terms of _{SiO 2, and ethylenediamine tetraacetic acid is used as a component (B).} Or an aminocarboxylic acid type chelating agent other than the component (B) as a component (C) or a salt thereof of 5% by mass or more, 20% by mass or less, and metal corrosion as a component (D). The inhibitor contains 0.01% by mass or more and 4.8% by mass or less, and water as the component (E), and the mass ratio of the component (B) to the component (C) is the value of (B) / (C). The total amount of sodium in the composition is 3.9% by mass or less.

Further, in the method for washing dishes by the automatic dishwasher of the present invention, the concentrated liquid cleaning agent composition for the automatic dishwasher of the present invention is supplied to the washing liquid tank of the automatic dishwasher to obtain 0.01% by mass or more. A diluting step of diluting to a range of 15% by mass or less to prepare a diluted washing liquid, a heating and holding step of heating and holding the diluted washing liquid in the washing liquid tank of an automatic dishwasher, and a heated diluted washing liquid in the washing liquid tank in the washing machine chamber. It is characterized by including a washing step of injecting into the washing machine to wash the dishes arranged in the washing machine, and a step of injecting a rinsing solution into the washing machine to rinse the dishes.

The concentrated liquid detergent composition for an automatic dishwasher of the present invention exhibits high detergency even when used at a low concentration, and is excellent in metal corrosion against metals that are easily corroded by the influence of alkalis such as copper alloys and aluminum. In addition to being excellent in prevention, the generation of silica scale is suppressed, and good storage stability is exhibited.
The method for cleaning dishes by the automatic dishwasher of the present invention using the concentrated liquid detergent composition for an automatic dishwasher of the present invention is to wash dishes with high detergency using a washing solution diluted to a low concentration. Can be done. In addition, the washing method of the present invention prevents metal corrosion and generation of silica scale in the automatic dishwasher, so that maintenance work of the automatic dishwasher can be reduced and the life of the machine can be extended. ..

Concentrated liquid detergent composition for automatic dishwasher of the present invention (hereinafter, may be simply referred to as the detergent composition of the present invention), alkali metal silicate as the component (A), ethylenediaminetetraacetic acid or ethylenediaminetetraacetic acid as the component (B). The salt, an aminocarboxylic acid type chelating agent other than the component (B) or a salt thereof as the component (C), a metal corrosion inhibitor as the component (D), and water as the component (E) are contained.
In the detergent composition of the present invention, the component (A) is _{1% by mass or more and 8% by mass or less in terms of SiO 2} , the component (B) is 1% by mass or more and 10% by mass or less, and the component (C) is 5% by mass. % Or more and 20% by mass or less, and the component (D) is contained in the range of 0.01% by mass or more and 4.8% by mass or less. In such a blending ratio, the mass ratio of the component (B) to the component (C) is 0.1 or more and 0.9 or less in terms of the values of (B) / (C), and the total amount of sodium in the detergent composition. Is adjusted to be 3.9% by mass or less.

According to the detergent composition of the present invention, an alkali metal silicate which is a component (A) is contained instead of sodium hydroxide which is generally used as a main detergent component, and a metal corrosion inhibitor which is a component (D). By including, good detergency and prevention of metal corrosion such as copper and aluminum can be achieved. The detergent composition of the present invention further contains the above-mentioned components (B) and (C) as a chelating agent in a predetermined blending ratio, so that storage stability is good and silicate is the main cleaning component. Although it is included, the generation of silica scale in the dishwasher is well prevented.
Regarding the present invention, the chelating agent is an agent capable of forming a compound in which a polydentate ligand is coordinated by a bond such as a hydrogen bond with a metal ion or the like, and is used in a cleaning agent composition. A wide range of chelate compounds to be obtained. Further, in the present invention, the aminocarboxylic acid type chelating agent refers to a chelating agent having an amino group in the molecule and a carboxyl group bonded thereto.
The details of the detergent composition of the present invention will be described below.

The alkali metal silicate of the component (A) is a salt composed of silicon dioxide and an alkali metal oxide, and one or more of the alkali metal silicates that can be used as a component of a cleaning agent for an automatic dishwasher. , Can be selected as appropriate. Specific examples of the component (A) include, for example, sodium orthosilicate, potassium orthosilicate, sodium metasilicate, potassium metasilicate, sodium No. 1 sodium silicate, No. 2 sodium silicate, and No. 3 specified in JIS K1408. Sodium silicate, trade name manufactured by Nippon Kagaku Kogyo Co., Ltd .; examples thereof include potassium A silicate, potassium B silicate, potassium C silicate and the like, sodium metasilicate pentahydrate, sodium metasilicate 9 hydroxide and the like.
More specifically, the component (A) is preferably a compound containing silicon dioxide and potassium oxide or sodium oxide, and from the viewpoint of providing a cleaning agent composition showing better storage stability. , (A) is more preferably a potassium salt containing potassium as an alkali metal.

In the detergent composition of the present invention, the component (A) is contained in the range of 1% by mass or more and 8% by mass or less in terms of _{SiO 2.}
If the content of the component (A) in _{terms of SiO 2} is less than 1% by mass, the detergency is not sufficient and it is difficult to show excellent aluminum corrosion prevention. From the viewpoint of improving detergency and aluminum corrosion prevention property, the component (A) is preferably 2% by mass or more, more preferably 3% by mass or more in terms of _{SiO 2.}
Further, if the content of the component (A) in _{terms of SiO 2} exceeds 8% by mass, adhesion of silica scale may become a problem, and the storage stability of the detergent composition may be lowered. From the viewpoint of preventing silica scale and improving storage stability, the component (A) is preferably 6% by mass or less, more preferably 5% by mass or less in terms of _{SiO 2.}

The component (B), ethylenediaminetetraacetic acid or a salt thereof, is a kind of chelating agent that can be used as a cleaning agent for an automatic dishwasher. Specific examples of the component (B) include ethylenediaminetetraacetic acid or an alkali metal salt thereof, and more specifically, for example, ethylenediaminetetraacetic acid, potassium ethylenediaminetetraacetate, sodium ethylenediaminetetraacetate, and ethylenediaminetetraacetic acid. Examples thereof include acetic acid monoethanolamine salts, and these are used in one kind or a combination of two or more kinds.

Ethylenediaminetetraacetic acid sodium can be appropriately used as the component (B) within a predetermined range of the total sodium amount described later, but from the viewpoint of exhibiting better storage stability, potassium ethylenediaminetetraacetate as the component (B) It is more preferable that potassium ethylenediaminetetraacetate is 90% by mass or more in 100% by mass of the component (B), and it is further preferable that the component (B) is substantially potassium ethylenediaminetetraacetate.

In the detergent composition of the present invention, the component (B) is contained in the range of 1% by mass or more and 10% by mass or less.
If the content of the component (B) is less than 1% by mass, the generation of silica scale in the automatic dishwasher may become a problem. From the viewpoint of better preventing the generation of silica scale, the component (B) is preferably 1.5% by mass or more, and more preferably 2.0% by mass or more.
Further, if the content of the component (B) exceeds 10% by mass, the storage stability may be deteriorated and the aluminum corrosion prevention property may be lowered. Therefore, from the viewpoint of improving storage stability and aluminum corrosion prevention property, the component (B) is preferably 7.0% by mass or less, and more preferably 4.0% by mass or less.

The component (C) is an aminocarboxylic acid type chelating agent other than the component (B) or a salt thereof, which is used in combination with the component (B).
The component (C) is a kind of chelating agent that can be used as a cleaning agent for an automatic dishwasher, and one kind or two or more kinds are selected from those other than the above component (B). Specific examples of the component (C) include hydroxyethyliminodiacetic acid, hydroxyethylenediaminetriacetic acid, diethylenetriaminopentaacetic acid, triethylenetetraaminehexacetic acid, hydroxyethyliminodiacetic acid, hydroxyiminodiacetic acid, and methyl. Examples thereof include glycine diacetic acid, glutamate diacetic acid, nitrilotriacetic acid or salts thereof. The salt generally refers to a metal salt, and from the viewpoint of anti-scaling property, an alkali metal salt such as a potassium salt or a sodium salt is particularly preferable.

Among the components (C) listed above, preferred examples are hydroxyethyliminodiacetic acid, hydroxyethylenediaminetriacetic acid, diethylenetriaminopentaacetic acid, triethylenetetraaminehexacetic acid, hydroxyethyliminodiacetic acid, and hydroxyiminodiacetic acid. , Methylglycine diacetic acid, glutamate diacetic acid, or one or more selected from alkali metal salts of nitrilotriacetic acid.

Among them, methylglycine diacetic acid or a salt thereof, glutamic acid diacetic acid or a salt thereof, nitrilotriacetic acid or a salt thereof are preferable as the component (C) to be used in combination with the component (B) described above, and these alkali metal salts may be used. More preferred. From the viewpoint of more satisfactorily exhibiting aluminum corrosion prevention property, it is particularly preferable to select the sodium salt of methylglycine diacetic acid and / or the sodium salt of glutamate diacetic acid as the component (C). However, if the sodium concentration in the detergent composition becomes too high, the storage stability may be insufficient. Therefore, even when a sodium salt is selected as the component (C), it is contained in the composition described later. It is important to adjust the total amount of sodium so that it is below a predetermined range.

In the detergent composition of the present invention, the component (C) is contained in the range of 5% by mass or more and 20% by mass or less.
When the content of the component (C) is less than 5% by mass, silica scale tends to be easily generated. From the viewpoint of better preventing the generation of silica scale, the component (C) is preferably 6% by mass or more, and more preferably 7% by mass or more.
Further, if the content of the component (C) exceeds 20% by mass, the storage stability may be poor and the aluminum corrosion prevention property may not be sufficient. Therefore, from the viewpoint of achieving good storage stability and aluminum corrosion prevention property, the component (C) is preferably 15% by mass or less, and more preferably 12% by mass or less.

The component (D) can be appropriately selected and used as a so-called metal corrosion inhibitor from compounds that can be used as a cleaning agent for an automatic dishwasher. For example, as component (D), triazole compounds such as benzotriazole, triltriazole, 5-phenyl-benzotriazole, 1-hydroxybenzotriazole, or 5-nitro-benzotriazole; benzimidazole, 2-mercaptobenzimidazole, chia. Imidazole compounds such as zolylbenzimidazole and 4-methyl-2-phenylimidazole; benzothiazole, or 2-mercaptobenzothiazole, 3- (2-benzothiadylthio) propionic acid, (2-benzothiazilthio). A thiazole-based compound such as acetic acid; at least one selected from a thiazyl-based compound such as dimercaptothiazazole or a derivative thereof can be contained.
From the viewpoint of metal corrosion prevention, it is preferable that the component (D) contains at least one selected from a triazole-based compound, an imidazole-based compound, a thiazole-based compound, or a derivative thereof.

Among the components (D) exemplified above, it is more preferable that one or more metal corrosion inhibitor represented by the following general formula (1) and / or the following general formula (2) is contained. The detergent composition of the present invention containing at least one of these compounds as the component (D) is particularly preferable in terms of corrosion resistance to copper alloys. More specifically, as the component (D), one or more compounds represented by the following general formula (1), one or more compounds represented by the following general formula (2), or the following general formula ( It is preferable that one or more compounds represented by 1) and one or more compounds represented by the following general formula (2) are contained.

（式中、Ｘは水素、アルカリ金属、アルカノールアミン、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３の何れか、Ｙは水素、アルカリ金属、ハロゲン、ＣＨ_３、ＣＯＯＭ、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３、ＮＨ_２、ＮＯ_２、ＳＯ_３Ｍの何れかであり、Ｍは水素、アルカリ金属の何れかである。）

（式中、Ｘは水素、アルカリ金属、アルカノールアミン、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３の何れか、Ｙは水素、アルカリ金属、ハロゲン、ＣＨ_３、ＣＯＯＭ、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３、ＮＨ_２、ＮＯ_２、ＳＯ_３Ｍの何れかであり、Ｍは水素、アルカリ金属の何れかである。）

(In the formula, X is hydrogen, alkali metal, alkanolamine, CH ₂ COOM, CH ₂ CH ₂ COOM, OCH ₃ , Y is hydrogen, alkali metal, halogen, CH ₃ , COOM, CH ₂ COOM, CH ₂ CH ₂ COM, OCH ₃ , NH ₂ , NO ₂ , SO ₃ M, and M is either hydrogen or alkali metal.)

(In the formula, X is hydrogen, alkali metal, alkanolamine, CH ₂ COOM, CH ₂ CH ₂ COOM, OCH ₃ , Y is hydrogen, alkali metal, halogen, CH ₃ , COOM, CH ₂ COOM, CH ₂ CH ₂ COM, OCH ₃ , NH ₂ , NO ₂ , SO ₃ M, and M is either hydrogen or alkali metal.)

The above general formula (1) is a general formula of a compound contained in a thiazole-based compound and having a 2-mercaptobenzothiazole skeleton. For example, among the compounds represented by the above general formula (1), examples of particularly preferable compounds include 2-mercaptobenzothiazole, 3- (2-benzothiazilthio) propionic acid, and (2-benzothiadi). Lucio) Acetic acid and the like.
Further, the above general formula (2) is a general formula of a compound contained in an imidazole-based compound and having a 2-mercaptobenzimidazole skeleton. For example, among the compounds represented by the above general formula (2), examples of particularly preferable compounds include 2-mercaptobenzimidazole, 2-mercaptomethylbenzoimidazole, 2-mercaptoaminobenzoimidazole and the like.

In the detergent composition of the present invention, the component (D) is contained in the range of 0.01% by mass or more and 4.8% by mass or less.
If the content of the component (D) is less than 0.01% by mass, it is difficult to sufficiently exhibit the metal corrosion inhibitory property, particularly the copper corrosion inhibitory property. From the viewpoint of satisfactorily exhibiting copper corrosion prevention property, the component (D) is preferably 0.05% by mass or more, and more preferably 0.1% by mass or more.
Further, if the content of the component (D) exceeds 4.8% by mass, the storage stability tends to be poor, and further effects due to excessive addition cannot be expected. From the viewpoint of obtaining good storage stability without any economic disadvantage, the component (D) is preferably 4.5% by mass or less, and more preferably 4.0% by mass or less.

The water of the component (E) is not particularly limited, and examples thereof include ion-exchanged water, soft water, pure water, tap water, and the like, and ion-exchanged water or pure water is preferable from the viewpoint of stability of the cleaning agent composition. As tap water, for example, tap water in Arakawa-ku, Tokyo (pH = 7.6, total alkalinity (converted to calcium carbonate) 40.5 mg / L, German hardness 2.3 ° DH (of which calcium hardness 1. 7 ° DH, magnesium hardness 0.6 ° DH), chloride ion 21.9 mg / L, sodium and its compounds 15 mg / L, nitrate nitrogen and nitrite nitrogen 1.2 mg / L, fluorine and its compounds 0. 1 mg / L, boron and its compounds 0.04 mg / L, total trihalomethane 0.016 mg / L, residual chlorine 0.4 mg / L, organic matter (total organic carbon content) 0.7 mg / L). Water is blended so that the total amount of the cleaning agent composition is 100% by mass (when the component (F) described later or other optional component is blended as necessary, the total content including these is 100% by mass. (Combined in).

The detergent composition of the present invention further includes an embodiment containing a polycarboxylic acid type polymer as the component (F).
In the aspect of the present cleaning agent composition containing the component (F), it is preferable to contain 0.01% by mass or more, and 0.1% by mass or more, from the viewpoint of being able to exhibit more excellent silica scale adhesion prevention property. Is more preferable, and 0.2% by mass or more is further preferable. Further, from the viewpoint of maintaining good storage stability while exhibiting good silica scale adhesion prevention property, the component (F) is preferably contained in the range of 8% by mass or less, and is preferably 6% by mass or less. It is more preferably contained in the range, and further preferably contained in the range of 5% by mass or less.

As the component (F), polyacrylic acid, polymethacrylic anhydride, polymaleic acid, polyitaconic acid, acrylate-methacrylic anhydride copolymer, acrylate-maleic anhydride copolymer, acrylate-sulfonic acid copolymer, olefin- Maleic anhydride copolymer, maleic anhydride-styrene copolymer, maleic anhydride-ethylene copolymer, maleic anhydride-vinyl acetate copolymer, maleic anhydride-acrylic acid ester copolymer, etc., or these It preferably contains at least one selected from salts. As the salt, an alkali metal salt such as a sodium salt or a potassium salt is preferable.
Among them, from the viewpoint of improving the silica scale adhesion prevention property, the components (F) include polyacrylic acid, polymaleic acid, acrylic acid-maleic acid copolymer, olefin-maleic acid copolymer, and acrylic acid-sulfonic acid. It preferably contains at least one selected from the polymer or salts thereof. As the salt, an alkali metal salt such as a sodium salt or a potassium salt is preferable.

The weight average molecular weight of the polycarboxylic acid type polymer (F) is preferably 200 or more and 20000 or less, more preferably 500 or more and 15000 or less, and further preferably 1500 or more and 8000 or less. If the weight average molecular weight is less than 200, it may be unfavorable in terms of silica scale adhesion prevention property, and if it exceeds 20000, it may be unfavorable in terms of storage stability.

The detergent composition of the present invention described above appropriately contains a compound containing sodium such as a sodium salt. In the detergent composition of the present invention, the detergency and anti-scale property can be improved by containing sodium in an appropriate range. On the other hand, in the detergent composition containing an alkali metal silicate as in the present invention, if the amount of sodium is too large, it may be disadvantageous in improving the storage stability. Therefore, the composition of each composition is adjusted so that the total amount of sodium in the detergent composition of the present invention is 3.9% by mass or less. From the viewpoint of achieving better storage stability, the total sodium content is preferably 3.5% by mass or less, more preferably 3.0% by mass or less, still more preferably 2.6% by mass. It is less than or equal to, and particularly preferably 2.4% by mass or less. On the other hand, the lower limit of the total sodium amount is not particularly limited, but is preferably 0.5% by mass or more, more preferably 0.8% by mass or more, and further preferably 1.0% by mass or more. preferable.

By the way, as described above, the detergent composition of the present invention contains an alkali metal silicate which is a component (A) as a main cleaning component. Here, the cleaning agent composition of the present invention does not prohibit the inclusion of sodium hydroxide, which is widely used as a cleaning agent component. However, the inclusion of sodium hydroxide may have an undesired effect on storage stability and may impair aluminum corrosion protection. Therefore, in the detergent composition of the present invention, the content of sodium hydroxide is preferably less than 3% by mass, more preferably less than 1% by mass, and substantially 0% by mass. Is more preferable.

Next, the blending ratio of the components contained in the detergent composition of the present invention will be described.
The detergent composition of the present invention is adjusted so that the mass ratio of the component (B) to the component (C) is in the range of 0.1 or more and 0.9 or less in terms of the values of (B) / (C). .. By adjusting the two types of chelating agents used in combination to such a ratio, all of prevention of silica scale generation, prevention of aluminum corrosion, and storage stability can be improved in a well-balanced manner in the detergent composition. From this point of view, the value of (B) / (C) is preferably 0.2 or more and 0.8 or less, more preferably 0.25 or more and 0.7 or less, and 0.3 or more and 0. It is more preferably 6.6 or less. When the value of (B) / (C) is less than 0.1, the effect of storage stability and prevention of silica scale generation may be insufficient, while when it is larger than 0.9. May have an undesired effect on storage stability and aluminum corrosion protection.

Further, in order to further prevent the generation of silica scale, prevent aluminum corrosion, and satisfactorily improve the storage stability by adjusting the contents of the component (B) and the component (C), (in the detergent composition, The total content of the component B) and the component (C) is preferably adjusted to a range of 6% by mass or more and 25% by mass or less, and more preferably 7% by mass or more and 18% by mass or less. It is more preferable to adjust in the range of 8% by mass or more and 13% by mass or less. If the total content of the component (B) and the component (C) is less than 6% by mass, good prevention of silica scale generation may not be shown, and if the total exceeds 25% by mass. , May have an undesired effect on aluminum corrosion protection and storage stability.

The liquid alkaline detergent composition of the present invention may contain other components usually used in the art, if necessary, as long as the effects of the present invention are not impaired. Examples of such components include nonionic surfactants, disinfectants, oxidizing agents, defoaming agents, pH adjusters, enzymes, pigments, fragrances and the like.

Examples of the nonionic surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene alkyl ethers and polyoxyethylene polyoxypropylene alkyl ethers (ethylene oxide and propylene oxide may be random or block), polyoxyethylene alkenyl ethers, and the like. Polyoxyalkylene alkenyl ether such as polyoxyethylene polyoxypropylene alkenyl ether (ethylene oxide and propylene oxide may be random or block), polyethylene glycol propylene oxide adduct, polypropylene glycol ethylene oxide adduct, glycerin fatty acid ester or ethylene oxide adduct thereof. Things, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, alkyl polyglucosides, fatty acid monoethanolamides or ethylene oxide adducts thereof, fatty acids-N-methylmonoethanolamides or ethylene oxide adducts thereof, fatty acid diethanolamides or ethylene oxide adducts thereof. , Sucrose fatty acid ester, alkyl (poly) glycerin ether, polyglycerin fatty acid ester, polyethylene glycol fatty acid ester, fatty acid methyl ester ethoxylate, N-long chain alkyldimethylamine oxide and the like.

Examples of the disinfectant include thiazolins, hydantoins, iodo-2-propynylbutylcarbamate, isopropylmethylphenol, hexachlorophene, irgasan, triclosan and the like. Examples of thiazolins include 5-chloro-2-methyl-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, isothiazolin-3-one, 1,2-benzisothiazolin-3-one, Examples thereof include Nn-butyl-benzisothiazolin-3-one. Examples of hydantoins include 1,3-dimethylol-5,5-dimethylhydantoin, 1 or 3-monomethylol-5,5-dimethylhydantoin, dimethylhydantoin, 1,3-dichloro-5,5-dimethylhydantoin, 1, Examples thereof include 3-dichloroethylmethyl hydantoin.

Examples of the oxidizing agent include hypochlorites such as sodium hypochlorite and potassium hypochlorite, chlorates such as sodium chlorite and potassium chlorate, and chlorine such as sodium chlorate and potassium chlorate. Examples thereof include acid salts, perchlorates such as sodium perchlorate and potassium perchlorate, chlorinated isocyanurates such as sodium chlorinated isocyanurate and potassium chlorinated isocyanurate, chlorine dioxide and hydrogen peroxide. The oxidizing agent may be used alone or in combination of two or more. Of these, sodium hypochlorite is preferable from the viewpoint of economy.

Examples of the defoaming agent include silicone oil, polypropylene glycol, polybutylene glycol, polyethylene glycol polypropylene glycol copolymer, glycerin fatty acid ester and the like. Examples of the thickener include polyethylene glycol, ethylene glycol, 1,3-butylene glycol, polyhydric alcohol such as reduced starch saccharified product, polyvinyl alcohol, polyvinylpyrrolidone, hydroxyethyl cellulose, hydroxypropyl methyl cellulose and the like having an average molecular weight of 200 to 6,000. Examples thereof include cellulose derivatives and acrylic acid-based polymers. Hydrotropic agents include 2-ethylhexanoic acid and / or a salt thereof, caprylic acid and / or a salt thereof, alkenylsulfosuccinic acid and / or a salt thereof, metaxylene sulfonic acid and / or a salt thereof, alkyl (C6-10). Examples thereof include glucoside, octylamine oxide and decyldimethylamine oxide.

Examples of the pH adjuster include acetic acid, hydrochloric acid, sulfuric acid, nitric acid, citric acid, phosphoric acid, sodium acetate, sodium carbonate, sodium citrate, sodium hydrogen citrate, sodium phosphate, sodium hydrogen phosphate and the like. The pH adjuster may be used alone or in combination of two or more.

Examples of the enzyme include amylase, protease, lipase, cellulase, glucanase and the like.

Examples of the dye include natural dyes, synthetic dyes, and mixtures thereof. Examples of the fragrance include natural fragrances, synthetic fragrances, and blended fragrances thereof.

Next, a method of washing tableware by the automatic dishwasher of the present invention (hereinafter, also simply referred to as a washing method of the present invention) will be described. The cleaning method of the present invention enjoys the excellent cleaning properties of the detergent composition of the present invention, and can clean tableware satisfactorily. Further, the detergent composition of the present invention satisfactorily prevents the generation of silica scale in the automatic dishwasher cabinet, and also has a high effect of preventing metal corrosion of copper, aluminum and the like. Therefore, according to the cleaning method of the present invention, corrosion of metal parts inside the automatic dishwasher is prevented, and adhesion of silica scale is also suppressed, so that maintenance labor of the device is reduced and the length of the device is increased. The life can be extended.
The washing method of the present invention is a washing method carried out using the above-mentioned concentrated liquid detergent composition for an automatic dishwasher of the present invention, and includes a diluting step, a heat holding step, a washing step and a rinsing step. In addition, any other process may be carried out between each process.

The dilution step is a step of supplying the detergent composition of the present invention to the washing liquid tank of the automatic dishwasher and diluting it in the range of 0.01% by mass or more and 0.15% by mass or less to prepare a diluted washing liquid. The dilution ratio is preferably 0.02% by mass or more and 0.10% by mass or less, and more preferably 0.03% by mass or more and 0.08% by mass or less. The dilution ratio referred to here is based on the composition of the detergent composition used.
Since the detergent composition of the present invention is a concentrated liquid type cleaning agent, it can be made compact during transportation and can exhibit good cleaning performance even when diluted to a very thin concentration as described above during use. .. Therefore, the washing method of the present invention is particularly suitable for washing dishes by a commercial automatic dishwasher. In the dilution step, the method of supplying the cleaning agent composition to the cleaning liquid tank is not particularly limited, and may be automatic or manual.
Further, since this washing method has a high dilution rate as described above, when the purchased concentrated liquid detergent composition for an automatic dishwasher of the present invention is used while being stored for a long period of time without being used up immediately. There is. Here, since the detergent composition of the present invention is excellent in storage stability, it can be stored in a good state regardless of the storage environment in such long-term tube storage.
The diluent for diluting the cleaning agent composition in the dilution step may generally be water such as tap water, or from the viewpoint of water saving and the like, a part or all of the diluent may be used as a cleaning solution or a used cleaning solution. It may be used rinse water.

After the dilution step, a heat holding step is carried out. The heat holding step is a step of heating and holding the diluted washing liquid in the washing liquid tank of the automatic dishwasher. The heating temperature is about 50 ° C. to 80 ° C., and the detergency can be improved by heating the diluted cleaning liquid.

Next, the cleaning step is carried out using the diluted cleaning solution heated in the heating and holding step. The washing step is a step of injecting the heated diluted washing liquid in the washing liquid tank into the washing machine storage to wash the tableware arranged in the washing machine storage.

After the washing process is completed, the rinsing liquid is sprayed into the pre-washing machine to rinse the dishes.

In the rinsing step, the injection amount of the rinsing liquid is not particularly limited, but for example, it is preferable to inject the rinsing liquid in the range of 1 L or more and 3 L or less per ^{2500 cm 2 of the flat area of the washing machine to rinse the tableware.} By spraying 1 L or more of rinse water per area, tableware can be sufficiently rinsed, and by setting the rinse water per area to 3 L or less, the amount of water used in the rinse process can be reduced. It is preferable because it can meet the demand for water saving with a small amount. The detergent composition of the present invention has high detergency and can be diluted to a low concentration before use, so that it also has good rinsability. Therefore, in the cleaning method of the present invention, the total amount of rinse water used in one cleaning step can be reduced to 3 L or less, which can contribute to water saving.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. Tables 1 to 6 below show each component used in the formulation in the detergent compositions of Examples and Comparative Examples. The numerical values relating to the blending amounts shown in Tables 1 to 6 below are the ratio (mass%) of the pure content of each component to the detergent composition. In addition, the following tests were conducted using an automatic dishwasher manufactured by Hoshizaki Corporation: JWE-680AJ.

(A) Ingredient A-1: Potassium silicate 1 (manufactured by Nippon Chemical Industrial Co., Ltd .; A potassium silicate, pure content 40%, SiO ₂ equivalent 26.5%)
A-2: Potassium silicate 2 (Osaka Soda Co., Ltd., potassium orthosilicate, pure content 42%, SiO ₂ equivalent 10%)
A-3: Sodium silicate (Soda No. 3 silicate manufactured by Koei Chemical Industry Co., Ltd., pure content 38%, SiO ₂ equivalent 29%)

(B) Component B-1: Sodium ethylenediaminetetraacetate B-2: Potassium ethylenediaminetetraacetate B-3: Monoethanolamine tetraacetate ethylenediamine

(C) Component C-1: Sodium methylglycine diacetate C-2: Sodium glutamate C-3: Sodium nitrilotriacetate C-4: Sodium hydroxyiminodisuccinate

(D) Ingredients D-1: 2-Mercaptobenzimidazole D-2: 2-Mercaptobenzothiazole D-3: 3- (2-Benzothiazilthio) Propionic acid D-4: (2-Benzothiazilthio) D-5 Acetate: Benzothiazole D-6: Triltriazole

(E) Component E-1: Ion-exchanged water

(F) Component F-1: Sodium polyacrylate (weight average molecular weight is 4,000)
F-2: Sodium polymaleate (weight average molecular weight is 500)
F-3: Acrylic acid-maleic acid copolymer potassium (weight average molecular weight is 1,900)
F-4: Acrylic acid-sulfonic acid copolymer potassium (weight average molecular weight is 5,000)

Other components G-1: Sodium hydroxide G-2: Potassium chloride

* 1: Detergency test <object to be cleaned>
2 g of mayonnaise (manufactured by Kewpie Corp.) was uniformly applied to a glass dish having a diameter of 20 cm, and the contaminated dish was allowed to stand at room temperature for 24 hours to be dried as an object to be washed.
<Test method>
Each detergent composition was diluted with diluted water so that the concentration of the detergent composition was 0.03% by mass or 0.07% by mass, and a diluted detergent solution was prepared. Then, the diluted washing liquid was stored in the washing liquid tank of the automatic dishwasher, heated and held at 66 ° C., five contaminated dishes were installed in the washing rack, and washing and rinsing were performed under the following conditions. As the diluted water and rinse water of the detergent composition, artificial hard water prepared with calcium chloride to a German hardness of 3 ° DH was used.
<Cleaning conditions>
Cleaning temperature: 66 ° C
Cleaning time: 41 seconds Rinse water temperature: 82 ° C
Rinse time: 6 seconds Rinse water volume: 2L
<Evaluation of cleanability>
After washing and rinsing the dishes, the dishes were allowed to stand at room temperature for 24 hours to dry, and then irradiated and reflected by fluorescent light in a dark room to evaluate the residual state of dirt by visual judgment according to the following criteria.
<Evaluation criteria>
⊚: There is no difference compared to a clean dish.
◯: Only light cloudiness is observed.
Δ: Only spots are recognized.
X: Cloudy and spots are observed.
, Δ, ○, and ◎ were judged to be practical.

* 2: Silica scale adhesion prevention test The scale prevention property of the wall surface (excluding the inside of the washing liquid tank) inside the automatic dishwasher was evaluated by the following method. In this test, the diluted cleaning solution was not drained every cycle, but was used repeatedly, and the cleaning agent composition was supplied only for the amount diluted with rinse water to adjust the concentration to a predetermined level.
<Test method>
36 250 ml glasses are placed in the washing rack, and after repeating washing / rinsing / interval for 200 cycles with the diluted washing solution under the following conditions, the silica scale adhesion state in the automatic dishwasher is visually judged, and the following criteria are used. evaluated. The diluted cleaning solution was prepared with artificial hard water prepared with calcium chloride to a German hardness of 10 ° DH. Further, the diluted detergent solution is used repeatedly without draining, and after the second cycle, the detergent composition is supplied by the amount diluted by the rinse water to adjust the concentration of the detergent composition to 0.03% by mass, 0. It was kept at 07% by mass.
<Cleaning conditions>
Cleaning temperature: 66 ° C
Cleaning time: 41 seconds Rinse water temperature: 82 ° C
Rinse time: 6 seconds Rinse water volume: 2L
Interval: 5 seconds <Evaluation criteria>
⊚: No adhesion of silica scale was observed.
◯: Almost no adhesion of silica scale was observed.
Δ: Adhesion of silica scale was observed.
X: Significant adhesion of silica kale was observed.
, Δ, ○, and ◎ were judged to be practical.

* 3: Metal corrosion prevention test 1 (aluminum)
The test piece [aluminum (A1100P), length 75 mm × width 25 mm × thickness 1 mm] was prepared by washing it with a neutral detergent in advance, treating it with acetone, and drying it. Further, using calcium carbonate, the detergent composition was diluted to 0.1% by mass with artificial hard water prepared to have a German hardness of 3 ° DH to prepare diluted washing water. 100 mL of the diluted wash water was placed in a transparent polypropylene container with a lid having a capacity of 120 mL, a test piece was immersed therein, and the test piece was stored in a constant temperature machine at 60 ° C. for 24 hours. The test piece after storage was taken out, rinsed with ion-exchanged water and dried, and the surface condition of the test piece was visually observed and the corrosiveness was evaluated according to the following criteria. The presence or absence of corrosion was judged by changes in appearance such as discoloration of the surface of the test piece and reduction of gloss.
<Evaluation criteria>
⊚: No corrosion.
◯: There is almost no corrosion.
Δ: Some corrosion is observed, but there is no problem in use.
×: Severely corroded.
, Δ, ○, and ◎ were judged to be practical.

* 4: Metal corrosion prevention test 2 (aluminum)
The aluminum corrosion resistance in the automatic dishwasher was evaluated by the following method. In this test, the diluted cleaning solution was not drained every cycle, but was used repeatedly, and the cleaning agent composition was supplied only for the amount diluted with rinse water to adjust the concentration to a predetermined level.
<Test method>
The test piece [aluminum (A1100P), length 75 mm × width 25 mm × thickness 1 mm] was prepared by washing it with a neutral detergent in advance, treating it with acetone, and drying it. Further, using calcium chloride, the detergent composition was diluted to 0.07% by mass with artificial hard water prepared to have a German hardness of 3 ° DH to prepare diluted washing water.
After fixing the test piece in the washing machine and repeating washing / rinsing / interval for 100 cycles with the diluted washing solution under the following conditions, the appearance of the test piece in the automatic dishwasher is visually judged, and the corrosiveness is determined according to the following criteria. evaluated. From the second cycle onward, the diluted cleaning solution was supplied with the cleaning agent composition by the amount diluted with the rinse water to maintain the concentration of the cleaning agent composition at 0.07% by mass.
<Cleaning conditions>
Cleaning temperature: 66 ° C
Cleaning time: 41 seconds Rinse water degree: 82 ° C
Rinse time: 6 seconds Rinse water volume: 2L
Interval: 5 seconds <Evaluation criteria>
⊚: No corrosion.
◯: There is almost no corrosion.
Δ: Some corrosion is observed, but there is no problem in use.
×: Severely corroded.
, Δ, ○, and ◎ were judged to be practical.

* 5: Metal corrosion prevention test 3 (copper alloy)
Gunmetal test piece [gunmetal (BC-6), length 75 mm x width 25 mm x thickness 3 mm], pure copper test piece [pure copper (C1100P), length 75 mm x width 25 mm x thickness 1 mm], brass test piece [brass (C2801P)) , Length 75 mm x Width 25 mm x Thickness 1 mm] were prepared in advance by washing with a neutral detergent, treating with acetone, and drying. Using calcium carbonate, dilute the detergent composition to 0.1% by mass with artificial hard water prepared to a German hardness of 3 ° DH, place 100 mL in a 120 mL volume transparent polypropylene container with a lid, and each test in it. The pieces were immersed and stored in a thermostat at 60 ° C. for 24 hours. After storage, each test piece was taken out, rinsed with ion-exchanged water and dried, and the surface condition of the test piece was visually observed and the corrosiveness was evaluated according to the following criteria. The presence or absence of corrosion was judged by changes in appearance such as discoloration of the surface of the test piece and reduction of gloss.
<Evaluation criteria>
4 points: No corrosion.
3 points: There is almost no corrosion.
2 points: Some corrosion is seen, but there is no problem in use.
1 point: It was badly corroded.

Based on the above evaluation criteria, the degree of corrosion for each test piece was evaluated by points. Then, the average values of the gunmetal test piece, the pure copper test piece, and the brass test piece were calculated, and the corrosiveness was evaluated according to the following criteria.
⊚: Average value is 3.5 or more ○: Average value is 2.5 or more and less than 3.5 Δ: Average value is 1.5 or more and less than 2.5 ×: Average value is less than 1.5, △, ○ and ◎ were judged to be practical.

* 6: Low temperature storage stability test <Test method>
250 ml of the detergent composition was placed in a 250 ml transparent polypropylene container, covered, and stored in a constant temperature bath at −5 ° C. The shaking was repeated once a week, and this was carried out for one month, and the state of the detergent composition was evaluated according to the following criteria.
<Evaluation criteria>
◯: Stable with no precipitates or freezing.
Δ: Some precipitates are observed.
X: Precipitates or freezing are observed.
And, Δ and ○ were judged to be practical.

* 7: High temperature storage stability test <Test method>
250 ml of the detergent composition was placed in a 250 ml transparent polypropylene container, covered, and stored in a constant temperature bath at 40 ° C. and allowed to stand. After 6 months, the condition of the detergent composition was evaluated according to the following criteria.
<Evaluation criteria>
◯: Stable with no precipitates or turbidity.
Δ: Some precipitates and turbidity are observed.
X: Precipitates or turbidity are observed.
And, Δ and ○ were judged to be practical.

（式中、Ｘは水素、アルカリ金属、アルカノールアミン、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３の何れか、Ｙは水素、アルカリ金属、ハロゲン、ＣＨ_３、ＣＯＯＭ、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３、ＮＨ_２、ＮＯ_２、ＳＯ_３Ｍの何れかであり、Ｍは水素、アルカリ金属の何れかである。）

（式中、Ｘは水素、アルカリ金属、アルカノールアミン、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３の何れか、Ｙは水素、アルカリ金属、ハロゲン、ＣＨ_３、ＣＯＯＭ、ＣＨ_２ＣＯＯＭ、ＣＨ_２ＣＨ_２ＣＯＯＭ、ＯＣＨ_３、ＮＨ_２、ＮＯ_２、ＳＯ_３Ｍの何れかであり、Ｍは水素、アルカリ金属の何れかである。）
（６）更に（Ｆ）成分としてポリカルボン酸型ポリマーを０．０１質量％以上、８質量％以下含有する上記（１）〜（５）の何れか一項に記載の自動食器洗浄機用濃縮液体洗浄剤組成物。
（７）組成物中の水酸化ナトリウム含有量が３質量％未満である、上記（１）〜（６）の何れか一項に記載の自動食器洗浄機用濃縮液体洗浄剤組成物。
（８）上記（１）〜（７）の何れかに記載の自動食器洗浄機用濃縮液体洗浄剤組成物を自動食器洗浄機の洗浄液タンクに供給して０．０１質量％以上０．１５質量％以下の範囲に希釈し希釈洗浄液を調製する希釈工程、
希釈洗浄液を自動食器洗浄機の洗浄液タンク内で加熱保持する加熱保持工程、
洗浄液タンク内の加熱された希釈洗浄液を洗浄機庫内に噴射し当該洗浄機庫内に配置された食器類を洗浄する洗浄工程、
すすぎ液を洗浄機庫内に噴射して食器類をすすぐすすぎ工程、
を含むことを特徴とする自動食器洗浄機による食器類の洗浄方法。
（９）前記すすぎ工程において、すすぎ液を洗浄機の平面積２５００ｃｍ^２当たり、１Ｌ以上３Ｌ以下の範囲で噴射して食器類をすすぐ上記（８）に記載の自動食器洗浄機による食器類の洗浄方法。


The above embodiment includes the following technical ideas.
(1) Alkali metal silicate as a component (A) is 1% by mass or more and 8% by mass or less in terms of _{SiO 2.}
(B) 1% by mass or more and 10% by mass or less of ethylenediaminetetraacetic acid or a salt thereof as a component,
As a component (C), an aminocarboxylic acid type chelating agent other than the component (B) or a salt thereof 5% by mass or more, 20% by mass or less,
(D) As a component, a metal corrosion inhibitor of 0.01% by mass or more and 4.8% by mass or less,
(E) Water as an ingredient
The mass ratio of the component (B) to the component (C) is 0.1 or more and 0.9 or less as the value of (B) / (C), and the total amount of sodium in the composition is 3. A concentrated liquid detergent composition for an automatic dishwasher, which comprises 9% by mass or less.
(2) Concentrated liquid washing for an automatic dishwasher according to (1) above, wherein the total of the components (B) and (C) in the composition is 6% by mass or more and 25% by mass or less. Agent composition.
(3) The concentrated liquid detergent composition for an automatic dishwasher according to any one of (1) and (2) above, wherein the component (B) is potassium ethylenediaminetetraacetate.
(4) The component (C) contains at least one selected from methylglycine diacetic acid or a salt thereof, diacetic acid glutamate or a salt thereof, nitrilotriacetic acid or a salt thereof, hydroxyiminodisuccinic acid or a salt thereof ( The concentrated liquid detergent composition for an automatic dishwasher according to any one of 1) to (3).
(5) The automatic according to any one of (1) to (4) above, wherein the component (D) contains a metal corrosion inhibitor represented by the following general formula (1) and / or the following general formula (2). Concentrated liquid detergent composition for dishwashers.

(In the formula, X is hydrogen, alkali metal, alkanolamine, CH ₂ COOM, CH ₂ CH ₂ COOM, OCH ₃ , Y is hydrogen, alkali metal, halogen, CH ₃ , COOM, CH ₂ COOM, CH ₂ CH ₂ COM, OCH ₃ , NH ₂ , NO ₂ , SO ₃ M, and M is either hydrogen or alkali metal.)

(In the formula, X is hydrogen, alkali metal, alkanolamine, CH ₂ COOM, CH ₂ CH ₂ COOM, OCH ₃ , Y is hydrogen, alkali metal, halogen, CH ₃ , COOM, CH ₂ COOM, CH ₂ CH ₂ COM, OCH ₃ , NH ₂ , NO ₂ , SO ₃ M, and M is either hydrogen or alkali metal.)
(6) Concentration for an automatic dishwasher according to any one of (1) to (5) above, which further contains 0.01% by mass or more and 8% by mass or less of a polycarboxylic acid type polymer as the component (F). Liquid detergent composition.
(7) The concentrated liquid detergent composition for an automatic dishwasher according to any one of (1) to (6) above, wherein the content of sodium hydroxide in the composition is less than 3% by mass.
(8) The concentrated liquid detergent composition for an automatic dishwasher according to any one of (1) to (7) above is supplied to the cleaning liquid tank of the automatic dishwasher and is 0.01% by mass or more and 0.15% by mass. Diluting step to prepare a diluted washing solution by diluting to the range of% or less,
A heating and holding process that heats and holds the diluted washing liquid in the washing liquid tank of the automatic dishwasher.
A cleaning process in which the heated diluted cleaning liquid in the cleaning liquid tank is sprayed into the washing machine cabinet to wash the dishes placed in the washing machine cabinet.
Rinsing process of rinsing tableware by spraying rinsing liquid into the washing machine
A method of washing dishes by an automatic dishwasher, which comprises.
(9) In the rinsing step, the rinsing liquid is ^{sprayed in a range of 1 L or more and 3 L or less per 2500 cm 2} of a flat area of the washing machine to rinse the dishes. Washing the dishes by the automatic dishwasher according to (8) above. Method.

Claims (9)

Alkali metal silicate as a component (A) is 1% by mass or more and 8% by mass or less in terms of _{SiO 2.}
(B) 1% by mass or more and 10% by mass or less of ethylenediaminetetraacetic acid or a salt thereof as a component,
As a component (C), an aminocarboxylic acid type chelating agent other than the component (B) or a salt thereof 5% by mass or more, 20% by mass or less,
(D) As a component, a metal corrosion inhibitor of 0.01% by mass or more and 4.8% by mass or less,
(E) Water as an ingredient
The mass ratio of the component (B) to the component (C) is 0.1 or more and 0.9 or less as the value of (B) / (C), and the total amount of sodium in the composition is 3. A concentrated liquid detergent composition for an automatic dishwasher, which comprises 9% by mass or less. The concentrated liquid detergent composition for an automatic dishwasher according to claim 1, wherein the total of the component (B) and the component (C) in the composition is 6% by mass or more and 25% by mass or less. The concentrated liquid detergent composition for an automatic dishwasher according to any one of claims 1 or 2, wherein the component (B) is potassium ethylenediaminetetraacetate. Claims 1 to 3 in which the component (C) contains at least one selected from methylglycine diacetic acid or a salt thereof, diacetic acid glutamate or a salt thereof, nitrilotriacetic acid or a salt thereof, hydroxyiminodisuccinic acid or a salt thereof. The concentrated liquid detergent composition for an automatic dishwasher according to any one of. The concentrated liquid for an automatic dishwasher according to any one of claims 1 to 4, wherein the component (D) contains a metal corrosion inhibitor represented by the following general formula (1) and / or the following general formula (2). Detergent composition.

(In the formula, X is hydrogen, alkali metal, alkanolamine, CH ₂ COOM, CH ₂ CH ₂ COOM, OCH ₃ , Y is hydrogen, alkali metal, halogen, CH ₃ , COOM, CH ₂ COOM, CH ₂ CH ₂ COM, OCH ₃ , NH ₂ , NO ₂ , SO ₃ M, and M is either hydrogen or alkali metal.)

(In the formula, X is hydrogen, alkali metal, alkanolamine, CH ₂ COOM, CH ₂ CH ₂ COOM, OCH ₃ , Y is hydrogen, alkali metal, halogen, CH ₃ , COOM, CH ₂ COOM, CH ₂ CH ₂ COM, OCH ₃ , NH ₂ , NO ₂ , SO ₃ M, and M is either hydrogen or alkali metal.) The concentrated liquid detergent composition for an automatic dishwasher according to any one of claims 1 to 5, further containing 0.01% by mass or more and 8% by mass or less of a polycarboxylic acid type polymer as the component (F). The concentrated liquid detergent composition for an automatic dishwasher according to any one of claims 1 to 6, wherein the content of sodium hydroxide in the composition is less than 3% by mass. The concentrated liquid detergent composition for an automatic dishwasher according to any one of claims 1 to 7 is supplied to a washing liquid tank of the automatic dishwasher and diluted in the range of 0.01% by mass or more and 0.15% by mass or less. Dilution step to prepare the diluted cleaning solution,
A heating and holding process that heats and holds the diluted washing liquid in the washing liquid tank of the automatic dishwasher.
A cleaning process in which the heated diluted cleaning liquid in the cleaning liquid tank is sprayed into the washing machine cabinet to wash the dishes placed in the washing machine cabinet.
Rinsing process of rinsing tableware by spraying rinsing liquid into the washing machine
A method of washing dishes by an automatic dishwasher, which comprises. The method for washing dishes by the automatic dishwasher according to claim 8, wherein in the rinsing step, the rinsing liquid is sprayed in a range of 1 L or more and 3 L or less per ^{2500 cm 2 of a flat area of the washing machine to rinse the dishes.}