JP2012001663A - Liquid detergent composition for automatic dishwasher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid detergent composition for an automatic dishwasher which excels in compounding stability, and has high detergency also to compound staining.SOLUTION: The liquid detergent composition for an automatic dishwasher includes (a) glutamic acid diacetic acid or its salt, (b) an acrylic acid-maleic acid copolymer or its salt in which the molar ratio of acrylic acid/maleic acid is 0.6-9 and the weight-average molecular weight is 1,000-100,000, (c) a nonionic surfactant, and water, wherein the total content of (a) and (b) is 15-30 mass%, the content of (c) is 0.01-3 mass%, the mass ratio of (b)/(a) is 0.3-3, and the pH at 25°C is 6-8.

Description

    The present invention relates to a liquid detergent composition for an automatic dishwasher.

  Water-soluble polymer dispersants are blended in detergents for automatic dishwashers, but this has a high detergency against soils that contain calcium, such as tea astringents and proteins, and lipophilic soils. It is performed for the purpose of imparting or for the purpose of imparting a dispersion effect that suppresses the phenomenon of dirt reattaching to the tableware from the washing water. Moreover, as described in Patent Documents 1 to 3, a metal sequestering agent such as an organic acid such as glutamic acid diacetic acid, citric acid, methylglycine diacetic acid and a salt thereof is added to the cleaning agent for an automatic dishwasher. It has been known. On the other hand, in recent years, from the viewpoints of usability and elimination of undissolved residue, liquid-type automatic dishwasher cleaning agents as disclosed in Patent Documents 1 and 2 have been developed.

JP 2000-063894 A JP 2008-127490 A Special table 2010-500431 gazette

  However, when a water-soluble polymer dispersant is mixed with a liquid type automatic dishwasher detergent containing a large amount of a metal sequestering agent or alkali agent, the water-soluble polymer dispersant does not solubilize in the composition. However, separation / precipitation occurs immediately and a problem arises in blending stability. In Examples and Comparative Examples of Patent Document 1, a liquid composition containing sodium glutamate diacetate and an acrylic acid-maleic acid copolymer is described, but an acrylic acid-maleic acid copolymer is described. The maximum content is 0.05% by weight. Patent Document 2 is intended to obtain a liquid composition having excellent blending stability, but it is difficult to say that an excellent detergency can be obtained because the effect of suppressing the reattachment of dirt is low. In the example of Patent Document 3, a detergent for an automatic dishwasher containing a relatively large amount of sodium methylglycine diacetate, sodium citrate and an acrylic acid-maleic acid-vinylsulfonic acid copolymer is described. However, this is a powder composition, and does not suggest the problem of blending stability in a liquid composition or a solution to the problem. In other words, Patent Documents 1 to 3 do not suggest a solution means for the problem of blending stability as described above.

  In general, the dirt targeted by the cleaning agent for automatic dishwashers is formed by a mixture of food-derived components in some cases, so it may be very difficult to remove. For example, composite soils that are solidified by mixing proteins and oils and fats are strong soils, and it is desirable that they also exhibit sufficient detergency in a short time. Increasing the amount of the water-soluble polymer compound and the metal sequestering agent in the liquid type automatic dishwasher cleaner leads to an improvement in the cleaning power. However, as described above, it is difficult to achieve compatibility with the blending stability of the liquid composition.

  Accordingly, an object of the present invention is to improve the blending stability of a liquid detergent composition for automatic dishwashers containing a large amount of a sequestering agent and a water-soluble polymer dispersant and containing a nonionic surfactant. An object of the present invention is to provide a liquid detergent composition for an automatic dishwasher which is excellent and has a high detergency against composite dirt.

  In the present invention, (a) glutamic acid diacetic acid or a salt thereof (hereinafter referred to as component (a)), (b) a molar ratio of acrylic acid / maleic acid is 0.6 to 9, and a weight average molecular weight is 1,000 to 100. 1,000 acrylic acid-maleic acid copolymer or salt thereof (hereinafter referred to as component (b)), (c) a nonionic surfactant (hereinafter referred to as component (c)), and water, and (a) and The total content of (b) is 15-30% by mass, the content of (c) is 0.01-3% by mass, and the mass ratio of (b) / (a) is 0.3-3. The present invention relates to a liquid detergent composition for an automatic dishwasher having a pH of 6 to 8 at 25 ° C.

  According to the present invention, in a liquid automatic dishwashing detergent composition containing a large amount of a metal sequestering agent and a water-soluble polymer dispersant and containing a nonionic surfactant, the blending stability is excellent, In addition, a liquid detergent composition for an automatic dishwasher having a high detergency against composite soil is provided.

<(A) component>
The component (a) used in the present invention is glutamic acid diacetic acid or a salt thereof, and a sodium salt, potassium salt, alkanolamine salt, or ammonium salt can be used as the salt. Sodium salts and / or alkanolamine salts are preferred in terms of stability and detergency. The component (a) may be N, N-bis (carboxymethyl) -L-glutamic acid or a salt thereof.

  Component (a) may be added to the composition as a salt in advance, but from the viewpoint of the function as a metal sequestering agent, in the detergent composition, 2 of the four carboxyl groups of component (a) It is preferably a partially neutralized product in which -3 are salts.

  The component (a) of the present invention can be produced, for example, by the method described in JP-A-9-221697.

  When preparing the composition of this invention, it is suitable to mix | blend (a) component with the form of aqueous solution, and the density | concentration of aqueous solution is 10-80 mass%, Preferably it is 30-60 mass%.

  The liquid detergent composition for an automatic dishwasher of the present invention preferably contains 5 to 25% by mass, more preferably 6 to 20% by mass, and even more preferably 7 to 15% by mass of the component (a).

<(B) component>
The component (b) of the present invention is a specific acrylic acid-maleic acid copolymer dispersant and has a monomer constituent unit derived from acrylic acid and a monomer constituent unit of maleic acid. The monomer structural unit derived from maleic acid may be derived from maleic anhydride. As the component (b), a copolymer of acrylic acid and maleic acid or a salt thereof is used because it is excellent in oil stain detergency and recontamination. As the salt, a sodium salt, potassium salt, alkanolamine salt, or ammonium salt can be used. The salt of the copolymer may be either one using a salt-type compound as a monomer, neutralized after copolymerization, or a combination of both. The component (b) is preferably a salt of the copolymer.

  Component (b) has an acrylic acid / maleic acid molar ratio of 0.6 to 9, preferably 1 to 4, and more preferably 1.5 to 4. In addition, the molar ratio of acrylic acid / maleic acid in the component (b) can be determined by detecting a pyrolyzate of the copolymer by pyrolysis gas chromatography (PGC). In addition, the proportion of acrylic acid and maleic acid in the constituent monomer of component (b) is preferably 90 to 100 mol%, more preferably 95 to 100 mol%, and still more preferably 98 to 100 mol%. Substantially component (b) Is preferably a copolymer of acrylic acid and maleic acid or a salt thereof.

  The component (b) has a weight average molecular weight of 1,000 to 100,000, 5,000 to 80,000, and more preferably 10,000 to 40,000. It is preferable because of its excellent point.

  The weight average molecular weight of the component (b) of the present invention is determined by gel permeation chromatography using polyethylene glycol as a standard substance using a mixed solvent of acetonitrile and water (phosphate buffer) as a developing solvent.

  The liquid detergent composition for an automatic dishwasher of the present invention preferably contains 3.5 to 20% by mass, more preferably 5 to 16% by mass, and further preferably 5 to 12% by mass of the component (b).

  In addition, (b) component of this invention is below-mentioned (i) that the viscosity measured with the Brookfield viscometer in 20 degreeC of 0.2 mass% aqueous solution adjusted to pH 7.0 is less than 50 mPa * s. It is distinguished from polymer thickeners such as component).

  In the present invention, the total content of the component (a) and the component (b) in the composition is 15 to 30% by mass, preferably 15 to 27% by mass, and particularly preferably 17 to 25% by mass. In addition, from the viewpoint of detergency against composite dirt, the mass ratio of component (b) / component (a) is 0.3 to 3, preferably 0.5 to 2, and particularly preferably 0.5 to 1.7. . When the total content of the component (a) and the component (b) is within the above range by combining the component (a) and the component (b) in such a content and mass ratio, the composite stain is reduced. On the other hand, it is possible to obtain a liquid detergent composition for an automatic dishwasher that exhibits excellent detergency. That is, the present invention relates to (a) component and (b) component as the types and compositions of the metal sequestering agent and water-soluble polymer dispersant that can be blended in a high concentration in the liquid-type automatic dishwasher detergent composition. It has been found that by combining the specific content and mass ratio, and further blending a predetermined amount of the component (c), it is possible to improve the detergency against composite dirt while maintaining blending stability.

<(C) component>
The component (c) used in the present invention is a nonionic surfactant from the viewpoint of blending stability and detergency against composite dirt. Specifically, the polyoxyalkylene type nonionic surfactant (polyoxyalkylene) Nonionic interface containing ethylene monoalkyl or monoalkenyl ether, polyoxyethylene alkylphenyl ether, polyoxypropylene monoalkyl or monoalkenyl ether, polyoxybutylene monoalkyl or monoalkenyl ether, alkylene oxide added monoalkyl group or monoalkenyl group Active agent mixtures, etc.), sucrose fatty acid esters, aliphatic alkanolamides, fatty acid glycerin monoesters, amine oxides, and glycoside nonionic surfactants (alkyl glycosides, etc.). Specific examples of such nonionic surfactants include the following (1) to (11).

(1) Polyoxyalkylene monoalkyl or monoalkenyl ether type nonionic surfactant, in particular, the alkyl group or alkenyl group has an average carbon number of 8 to 20, and the average added mole number of alkylene oxide is more than 0 to 110. In addition, the average number of moles of ethylene oxide added is 1 to 30 moles. Preferable compounds include polyoxyalkylene monoalkyl or monoalkenyl ether type nonion represented by the following general formula (c1), and polyoxyethylene monoalkyl or monoalkenyl represented by the following general formula (c1-1). Mention may be made of ethers.
R ¹¹ [(OC ₂ H ₄ ) _l / (OC ₃ H ₆ ) _m ] OH (c1)
[Wherein R ¹¹ is a hydrocarbon group having 8 to 18 carbon atoms, l and m are average added mole numbers, l is a number from 0 to 10, and m is a number from 0 to 100, l and m are not 0 at the same time. “/” Indicates that the oxyethylene group and the oxypropylene group may be added randomly or in a block regardless of the order. ]
R ^{11 ′} O (OC ₂ H ₄ ) _m H (c1-1)
[Wherein, R ^{11 ′} is an alkyl group or alkenyl group having 8 to 18 carbon atoms, m is an average added mole number, and is a number of 1 to 6. ]

(2) Polyoxyethylene alkylphenyl ether, wherein the alkyl group has an average carbon number of 6 to 12 and the average number of moles of ethylene oxide added is 1 to 25 mol.

(3) Polyoxypropylene monoalkyl or monoalkenyl ether, wherein the alkyl group or alkenyl group has an average carbon number of 8 to 20 and the average number of propylene oxide addition moles of 1 to 20 mol.

(4) Polyoxybutylene monoalkyl or monoalkenyl ether, wherein the alkyl group or alkenyl group has an average carbon number of 8 to 20 and an average number of moles of butylene oxide addition of 1 to 20 mol.

(5) Having an alkyl group or alkenyl group only at one end, ethylene oxide and propylene oxide (molar ratio of ethylene oxide / propylene oxide is 0.01 to 99) or ethylene oxide and butylene oxide (of ethylene oxide / propylene oxide) A nonionic surfactant mixture obtained by adding a molar ratio of 0.01 to 99), wherein the average number of carbon atoms of the alkyl group or alkenyl group is 8 to 20, and the number of moles of alkylene oxide added per molecule Is an average of 1 to 30 moles.

(6) A higher fatty acid alkanolamide represented by the following general formula (c2) or an alkylene oxide adduct thereof.

[Wherein R ²¹ is an alkyl group or alkenyl group having 10 to 20 carbon atoms, R ²² and R ²³ are the same or different and are a hydrogen atom or a methyl group, p is a number of 1 to 3, and q is 0 It is a number of ~ 3. ]

(7) Sucrose fatty acid ester whose fatty acid part has an average carbon number of 10-20.

(8) Fatty acid glycerin monoester, wherein the fatty acid moiety has an average carbon number of 10-20.

(9) Amine oxide. For example, the alkyl or alkenylamine oxide which has a C1-C24 linear or branched alkyl group or alkenyl group can be mentioned. More preferable amine oxides include alkylamine oxides represented by the following general formula (c3).

[Wherein R ³¹ is a hydrocarbon group having 6 to 24 carbon atoms, R ³² and R ³³ may be the same or different, and a hydrocarbon group having 1 to 3 carbon atoms, D is —COO—, — CONH—, a group selected from —O—, E is a divalent hydrocarbon group having 1 to 5 carbon atoms, a and b are a = 0 and b = 0, or a = 1 and b = 1. ]

(10) A glycoside nonionic surfactant. For example, a compound represented by the following general formula (c4).
R ⁴¹ (OR ⁴² ) _x G _y (c4)
[Wherein, R ⁴¹ represents a linear or branched alkyl group having 8 to 18 carbon atoms, an alkenyl group, or an alkylphenyl group, preferably an alkyl group, and R ⁴² represents an alkylene group having 2 to 4 carbon atoms. G is a residue derived from a reducing sugar having 5 to 6 carbon atoms. x (average value) is 0-5, and y (average value) is 1-5. ]

The value of x in the general formula (c4) is preferably 0 to 2, particularly preferably 0. Moreover, the average value of y in general formula (c4) is 1-5, Preferably it is 1-1.5, More preferably, it is 1.1-1.4. In addition, the measured value of y is based on the proton NMR method. Preferred raw materials are glucose and fructose for monosaccharides, and maltose and sucrose for disaccharides and higher in view of their availability and cost. R ⁴¹ is preferably a linear or branched alkyl group having 8 to 18 carbon atoms in total.

(11) A linear or branched alkyl glyceryl ether having 5 to 20 carbon atoms.

  Among these nonionic surfactants, (1), (5), (6), (9), (10) and (11) are preferred, and (1), (5), (9), (10 ) And (11) are preferable, and (1) and (10) are more preferable. Therefore, the component (c) of the present invention is preferably at least one selected from polyoxyethylene monoalkyl or monoalkenyl ether and alkyl glycoside.

As the component (c), the polyoxyethylene alkyl or alkenyl ether represented by the general formula (c1-1) is preferably included. In this invention, it is preferable that carbon number of R < ^{11 '} > in general formula (c1-1) is 8-14 in the point of low-foaming property and detergency, and 12-14 carbon atoms are especially preferable. In addition, the alkyl group or alkenyl group of R ^{11 ′} in formula (c1-1) is particularly preferably derived from a secondary alcohol. Moreover, as for the average addition mole number m of the ethylene oxide of general formula (c1-1), 2-4 are preferable. In the nonionic surfactant of the general formula (c1) and (c1-1), the remaining unreacted alcohol is preferably 2% by mass or less.

  The liquid detergent composition for an automatic dishwasher of the present invention has a component (c) of 0.01 to 3% by mass, preferably 0.1 to 2.8, from the viewpoint of blending stability and detergency against composite dirt. It is contained by mass%, more preferably 0.5 to 2.8 mass%, still more preferably 1.5 to 2.5 mass%. Further, from the viewpoint of blending stability, the mass ratio of (c) component / [(a) component + (b) component] is preferably 0.05 to 0.3, more preferably 0.06 to 0.2. More preferably, it is 0.07-0.16.

<Other ingredients>
In the present invention, for the purpose of improving the blending stability and detergency, it is preferable to contain a polyvalent carboxylic acid type chelating agent having a molecular weight of 400 or less (hereinafter referred to as component (d)) other than component (a). May include compounds selected from malic acid or salts thereof, citric acid or salts thereof, succinic acid or salts thereof, maleic acid or salts thereof and fumaric acid or salts thereof.

  In the present invention, the mass ratio of the component (a) / the component (d) is 0.2 to 30, and further 2 to 20, which improves the effect of the component (a) and the component (b) and (c). It is preferable from the viewpoint of blending stability of components. The mass ratio of (b) component / [(a) component + (d) component] is preferably 0.2 to 2.5, more preferably 0.4 to 2.

  In the composition of the present invention, it is preferable from the viewpoint of the cleaning effect that a polypropylene glycol (hereinafter referred to as component (e)) having a weight average molecular weight of 600 to 20,000, preferably 2,000 to 10,000 is blended. It is preferable that the polypropylene glycol is blended in the composition in an amount of 0.1 to 10% by mass, further 0.5 to 5% by mass, particularly 1 to 5% by mass. The weight average molecular weight of polypropylene glycol can be determined using a light scattering method, and can be measured by a dynamic light scattering photometer (DLS-8000 series, manufactured by Otsuka Electronics Co., Ltd.).

  When polypropylene glycol is used as a solvent, in order to disperse uniformly in the composition, as component (c), at least one selected from the above (1), (5), (9) and (10) is used. It is preferable to use it. From the viewpoints of dispersion stability and low foamability, the mass ratio of the component (e) / (c) is preferably 0.1 to 9, more preferably 0.2 to 2.5, and still more preferably 0.4. ~ 1.5.

  The liquid detergent composition for an automatic dishwasher of the present invention preferably contains an enzyme as the component (f) for the purpose of further enhancing the cleaning effect.

  Specific examples include cellulase, protease, lipase, amylase, esterase, pectinase, lactase, and peroxidase, and protease and amylase are particularly preferable.

  Examples of commercially available enzymes that can be used as proteases include alcalase, sabinase, esperase, evalase, cannase, ovozyme (Novozymes Japan K.K.), Excellase, properase, Perfect OX, and Perfect L (Genencor Kyowa). .

  Examples of commercially available enzymes that can be used as amylases include Lapidase (Gist-Brokers), Termamyl, Duramil, Steinzyme (Novo Nordisk Bioindustry Co., Ltd.), Plaster HP A, Plaster OxAm (Genencor Kyowa). it can.

  In the present invention, it is preferable to use protease and amylase in combination, and the mass ratio of amylase / protease as the amount of enzyme protein is preferably 0.01 to 15, more preferably 0.02 to 9, and particularly preferably 0.2 to 9. 4.

  The amount of component (f) in the composition is preferably 0.005 to 1% by mass, more preferably 0.01 to 0.5% by mass, and still more preferably 0.03 to 0. 3% by mass.

  When the component (f) is added to the liquid detergent composition for an automatic dishwasher of the present invention, it is preferable to contain a water-soluble calcium salt [hereinafter referred to as the component (g)] as an enzyme stabilizer. As the water-soluble calcium salt, calcium chloride is preferable. (G) Content of a component becomes like this. Preferably it is 0.01-1 mass% in a composition, More preferably, it is 0.02-0.5 mass%, More preferably, it is 0.05-0.3 mass%.

  In the liquid detergent composition for an automatic dishwasher of the present invention, for the purpose of further improving the stability of the component (f), one or more solvents selected from ethylene glycol, propylene glycol, glycerin and sorbitol [hereinafter ( h) component] is preferably added. Component (h) is preferably propylene glycol and / or glycerin, and the content in the composition is preferably 1 to 10% by mass, more preferably 1 to 5% by mass, and still more preferably 1 to 3% by mass. .

    The composition of the present invention preferably further contains a thickener as component (i). Examples of the component (i) include pectin, carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, tragacanth gum, carrageenan, locust bean gum, dextrin, dextrin fatty acid ester, (meth) acrylic acid polymer, xanthan gum. Water-soluble polymers such as guar gum, locust bean gum, gelatin, sodium alginate, gum arabic and starch, and water-swellable clay minerals such as smectite are preferred.

  As the smectite, both natural and synthetic can be used, but those having a glassy content, feldspar, quartz, mica, calcium sulfate, calcium carbonate, manganese carbonate and the like are preferably 5% by mass or less. Preferred smectites include natural or synthetic colloidal silicates such as dioctahedral montmorillonite, beidellite, nontroit, etc. or trioctahedral saponite, hectorite, stevensite. Of these, hectorite is preferable, and examples include Laponite series manufactured by Rockwood Additives, Kunipia manufactured by Kunimine Industries, and Smecton.

  The component (i) is preferably a (meth) acrylic acid polymer from the viewpoint of thickening and storage stability. Preferable (meth) acrylic acid polymers include carboxyvinyl polymer or a salt thereof (hereinafter referred to as (i-1) component) and a copolymer of (meth) acrylic acid and (meth) acrylic acid ester or a salt thereof [hereinafter, One or more types selected from (i-2) component] can be used. (Meth) acrylic acid means acrylic acid and / or methacrylic acid. Examples of the salt include sodium salt, potassium salt, alkanolamine salt, ammonium salt and the like, and any of those using a salt-type compound as a monomer or neutralized after copolymerization may be used together. It may be a thing.

  (I-1) The component carboxyvinyl polymer or a salt thereof is an acidic polymer compound having a carboxyl group, the main constituent monomer is acrylic acid, and is 0.01% by mass with respect to 100 parts by mass of acrylic acid. It may be a cross-linked polyacrylic acid or a salt thereof obtained by using a compound having at least two ethylenically unsaturated groups of 3 parts by weight or more and 3 parts by weight or less as a cross-linking agent. Those used in the above can be used without limitation.

  As the compound having at least two ethylenically unsaturated groups, for example, at least one of pentaerythritol tetraallyl ether, tetraallyloxyethane, triallyl phosphate, and polyallyl saccharose is preferable. It is preferable that a crosslinking agent is 0.05 mass part or more and 3 mass parts or less with respect to 100 mass parts of acrylic acid.

  The component (i-1) preferably has a constituent monomer of 99.9 mol% or more of acrylic acid, particularly acrylic acid alone or a salt thereof, or cross-linked polyacrylic acid or a salt thereof.

  As such a carboxyvinyl polymer or a salt thereof, for example, commercially available products such as Carbopol 980 and Carbopol 981 manufactured by Noveon Inc., and ACPEC HV501E and HV505E manufactured by Sumitomo Seika Co., Ltd. may be used. it can. These can also use 2 or more types together.

  The (meth) acrylic acid ester constituting the component (i-2) is preferably an alkyl group as the hydrocarbon group constituting the ester, and its carbon number is preferably 8 to 30, more preferably 10 to 30, and particularly preferably 10 to 22.

  The component (i-2) may contain a structural unit derived from an alkylene oxide having 2 to 4 carbon atoms (hereinafter referred to as AO). As AO, ethylene oxide, propylene oxide, preferably ethylene oxide is used. Can be mentioned. The average added mole number of AO is preferably 5-20.

  Moreover, (meth) acrylic acid ester 0.2-10 is preferable with respect to (meth) acrylic acid 100 by molar ratio, and the ratio of the monomer of (i-2) component is 0.5-5 especially preferable. In the case of introducing a structural unit derived from AO, the AO adduct of (meth) acrylic acid ester and / or the (meth) acrylic acid AO adduct is 0.2 in molar ratio to 100 of (meth) acrylic acid. Is preferably used.

  The component (i-2) preferably contains only acrylic acid and methacrylic acid alkyl ester as substantial constituent monomers, and in addition, 0.01 parts by mass or more of ethylene with respect to 100 parts by mass of acrylic acid. A cross-linked acrylic acid / alkyl acrylate copolymer or a salt thereof obtained by using a compound having at least two polymerizable unsaturated groups as a cross-linking agent is preferred.

  As the component (i-2), for example, commercially available products such as Carbopol ETD2020 manufactured by Noveon Inc., Akpec HV501ER, and Akpek HV701EDR manufactured by Sumitomo Seika Co., Ltd. can be used. These can also use 2 or more types together.

  The (i-1) component carboxyvinyl polymer or salt thereof, or (i-2) component (meth) acrylic acid and (meth) acrylic acid ester copolymer or salt thereof is (i-1) component or ( i-2) An aqueous solution containing 0.2% by mass of the component and adjusted to pH 7.0 with sodium hydroxide was measured at 20 ° C. with a Brookfield viscometer (rotor No. 4, rotation speed 12 r / m). The viscosity is preferably 500 mPa · s or more, more preferably 1,000 to 70,000 mPa · s, still more preferably 1,500 to 40,000 mPa · s.

  It is preferable that (i-2) component and / or (i-2) component exist in a cleaning composition as a salt with the below-mentioned pH adjuster.

  The liquid detergent composition for an automatic dishwasher according to the present invention contains the above-mentioned components (a) to (c), as well as optional components (d) to (i) that are water. A liquid composition dissolved in, emulsified and dispersed in, preferably in the form of an aqueous solution. The water used is preferably ion-exchanged water or distilled water from which a small amount of metal has been removed, and hypochlorous dissolved in 0.1 to 10 ppm of chlorine. It is also suitable to use chloric acid sterilized water.

  The pH (JIS-Z-8802: 1984 “pH measurement method”) at 25 ° C. of the liquid detergent composition for an automatic dishwasher of the present invention is 6 to 8, preferably 7 to 8 from the viewpoint of blending stability. It is. In order to obtain such a pH, a pH adjusting agent can be used. Specifically, an inorganic alkaline agent selected from sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, and an organic alkaline agent selected from amine compounds. Can be mentioned. As the amine compound, amine compounds represented by the following general formulas (I) to (IV) are suitable. An appropriate amount of the pH adjuster is appropriately added to adjust the pH of the liquid detergent composition of the present invention.

(In the formula, R ¹ , R ⁴ , R ⁶ , R ⁸ , R ¹⁰ , R ¹² , R ¹³ are each a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a hydroxyalkyl group having 2 to 4 carbon atoms. R ² , R ³ , R ⁵ , R ⁷ , R ⁹ and R ¹¹ each represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a hydroxyalkyl group having 2 to 4 carbon atoms.)

  Examples of the compound represented by the general formula (I) include monoethanolamine, diethanolamine, triethanolamine, N-methylpropanol, 2-amino-2-methyl-1-propanol and the like.

  Examples of the compound represented by the general formula (II) include N- (β-aminoethyl) ethanolamine.

  Examples of the compound represented by the general formula (III) include diethylenetriamine.

  Examples of the compound represented by the general formula (IV) include morpholine and N-ethylmorpholine.

  Among these, from the viewpoint of blending stability and cost of the cleaning composition, the inorganic alkali agent is preferably a hydroxide such as potassium hydroxide or sodium hydroxide, and the organic alkali agent is preferably monoethanolamine.

  The liquid detergent composition for an automatic dishwasher of the present invention preferably has a viscosity at 20 ° C. of 300 to 5,000 mPa · s, more preferably 400 to 4,000 mPa · s, and still more preferably 500 to 3 ,. 000 mPa · s, and such viscosity can be appropriately adjusted depending on the type and content of component (i). Viscosity is measured using a Brookfield viscometer (when the viscosity is 4,000 mPa · s or less, rotor No. 3, rotation speed 30 r / m, when the viscosity exceeds 4,000 mPa · s and is 20,000 mPa · s or less) Is carried out using rotor No. 4, rotation speed 30r / m).

  Moreover, the liquid detergent composition for automatic dishwashers of this invention is (a) component and / or (b) component in water, for example, the sum total of (a) component and (b) component is 15 mass% or more. It is preferable to adjust the pH at 25 ° C. to 5 or less using the pH adjuster described above, and when the component (i) is blended, after adjusting the pH in this way, (i) It is preferable to add and disperse the components. When the component (d) is blended, the pH can be adjusted with the component (d).

  Moreover, as a stirrer used when producing the detergent composition for an automatic dishwasher of the present invention, a stirrer that can be mixed under high shear conditions is preferable from the viewpoint of blending stability. Ajihomomica, Primix Co., Ltd. K. Homomixer, T.W. K. Homo disperse is preferred, and the continuous type is T.I. K. Pipeline homomixer, T.W. K. A homomic line mill or the like is preferable.

  Moreover, the liquid detergent composition for an automatic dishwasher of the present invention is preferably an emulsion, and in particular, the average particle diameter (median diameter) of the emulsified particles of the composition is less than 10 μm, and more preferably less than 5 μm. Preferably there is. In addition, the average particle diameter (median diameter) of the emulsified particles of the composition is a value measured with a particle size distribution meter (HORIBA LA-950V2, Horiba, Ltd.) using ion-exchanged water as a dispersion medium.

  With the compounding compositions shown in Tables 1 and 2, a liquid detergent composition for an automatic dishwasher was prepared and evaluated as follows.

<Composite dirt cleaning performance>
* Used washing machine Using an automatic dishwasher (model NP-P45M1PS) manufactured by Matsushita Electric Industrial Co., Ltd., the following tableware (contamination knife) and the liquid detergent composition for the automatic dishwasher shown in Table 1 or 2 are speedy I drove on the course.
Contamination knife: 6 (prepared by the following method)
Water used: 3.2 ° dH water Detergent composition added amount: 6 g

* Contamination knife preparation and evaluation method 3g of salad oil is put into a frying pan to make a half-ripe ham egg. As shown in the figure, dirt was attached to both sides of the knife and dried at room temperature for 2 hours for evaluation. After the cleaning, the remaining stains on the six knives were observed by a panel of four males and four females (two each), evaluated according to the following criteria, and the average value of the four was shown in Table 1. 2 shows.
4: Dirt does not remain 3: Dirt remains slightly, but there is no problem in use 2: Level where dirt remains and needs to be washed again 1: Level where dirt is hardly removed

<Compounding stability>
A liquid detergent composition was prepared by mixing the ingredients shown in Tables 1 and 2 with a homomixer, and the average particle diameter (median diameter) of the emulsified particles in the composition was determined using a particle size distribution meter ( HORIBA LA-950V2, Horiba Seisakusho). The case where the average particle diameter of the emulsified particles was less than 5 μm was evaluated as ◎, the case where it was 5 μm or more but less than 10 μm was evaluated as ◯, and the case where it was 10 μm or more was evaluated as x. In addition, when an average particle diameter will be 10 micrometers or more, an emulsified state will become unstable.

The components (partial) in the table are as follows.
<(B) component>
・ Acrylic acid / maleic acid copolymer salt 1: weight average molecular weight of about 30,000, acrylic acid / maleic acid molar ratio = 2.3, sodium salt / acrylic acid / maleic acid copolymer salt 2: Socaran CP45 (BASF Japan Ltd.) Company) Weight average molecular weight of about 70,000, acrylic acid / maleic acid molar ratio = 2.3, partial sodium salt

<Comparison of component (b)>
-Salt of polyacrylic acid: sodium polyacrylate, weight average molecular weight of about 30,000

<(C) component>
Nonionic surfactant 1: polyoxyethylene alkyl ether obtained by adding an average of 3 mol of oxyethylene groups to a secondary higher alcohol having 12 to 14 carbon atoms in the alkyl group [in general formula (c1-1), R ^{11 ′} is a secondary alkyl group having 12 to 14 carbon atoms, and m is a nonionic surfactant having 3)
Nonionic surfactant 2: polyoxyethylene alkyl ether in which an average of 4 mol of oxyethylene groups is added to a linear primary higher alcohol having 12 carbon atoms in the alkyl group [in formula (c1-1), R ^{11 ′} is a linear primary alkyl group having 12 carbon atoms, and m is a nonionic surfactant having 4)
Nonionic surfactant 3: polyoxyethylene alkyl ether obtained by adding an average of 8 moles of oxyethylene group to a linear primary higher alcohol having 12 carbon atoms in the alkyl group [in general formula (c1-1), R ^{11 ′} is a linear primary alkyl group having 12 carbon atoms, m is a nonionic surfactant having 8
And non-ionic surface active agent 4: the number of carbon atoms in the alkyl group 12, a straight-chain primary alkyl group R ⁴¹ in the average degree of condensation 1.3 alkyl glycosides of glucose [formula (c4) is 12 carbon atoms , G is a glucose residue, x is 0, and y is 1.3 alkylpolyglycoside]

<(E) component>
Polypropylene glycol: weight average molecular weight of about 3,000, average condensation degree of about 50 (diol type, Wako Pure Chemical Industries, Ltd.)
<Component (f)>
・ Α-Amylase: Termamyl Ultra 300L (Novozymes Japan Ltd.)
・ Protease: Everase 16L (Novozymes Japan K.K.)
<(I) component>
Thickener 1: ACPEC HV501E (cross-linked polyacrylic acid, manufactured by Sumitomo Seika Co., Ltd.) (viscosity at 20 ° C .: containing 0.2% by mass of ACPEC HV501E, adjusted to pH 7.0 with sodium hydroxide) The viscosity of the aqueous solution measured at 20 ° C. with a Brookfield viscometer <rotor No. 4, rotation speed 12 r / m> is 4,000 mPa · s)
Thickener 2: ACPEC HV701EDR [crosslinked acrylic acid / alkyl methacrylate (carbon number: 10 to 30) copolymer, manufactured by Sumitomo Seika Co., Ltd.] (viscosity at 20 ° C .: 0.2% by mass of ACPEC HV701EDR) An aqueous solution adjusted to pH 7.0 with sodium hydroxide was measured at 20 ° C. using a Brookfield viscometer <rotor No. 4, rotation speed 12 r / m> with a viscosity of 13,000 mPa · s)

(1) Polyoxyalkylene monoalkyl or monoalkenyl ether type nonionic surfactant, in particular, the alkyl group or alkenyl group has an average carbon number of 8 to 20, and the average added mole number of alkylene oxide is more than 0 to 110. In addition, the average number of moles of ethylene oxide added is 1 to 30 moles. Preferable compounds include polyoxyalkylene monoalkyl or monoalkenyl ether type nonion represented by the following general formula (c1), and polyoxyethylene monoalkyl or monoalkenyl represented by the following general formula (c1-1). Mention may be made of ethers.
R ¹¹ [(OC ₂ H ₄ ) _l / (OC ₃ H ₆ ) _m ] OH (c1)
[Wherein R ¹¹ is a hydrocarbon group having 8 to 18 carbon atoms, l and m are average added mole numbers, l is a number from 0 to 10, and m is a number from 0 to 100, l and m are not 0 at the same time. “/” Indicates that the oxyethylene group and the oxypropylene group may be added randomly or in a block regardless of the order. ]
_{^{R 11 '(OC 2 H 4}} ) m O H (c1-1)
[Wherein, R ^{11 ′} is an alkyl group or alkenyl group having 8 to 18 carbon atoms, m is an average added mole number, and is a number of 1 to 6. ]

Claims (4)

  (A) glutamic acid diacetic acid or a salt thereof, (b) an acrylic acid-maleic acid copolymer or salt thereof having a molar ratio of acrylic acid / maleic acid of 0.6 to 9, and a weight average molecular weight of 1,000 to 100,000, (C) It contains a nonionic surfactant and water, the total content of (a) and (b) is 15 to 30% by mass, and the content of (c) is 0.01 to 3% by mass. A liquid detergent composition for an automatic dishwasher, wherein (b) / (a) has a mass ratio of 0.3 to 3 and a pH at 25 ° C. of 6 to 8.   The liquid detergent composition for an automatic dishwasher according to claim 1, wherein the mass ratio of (c) / [(a) + (b)] is 0.05 to 0.3.   The liquid washing for an automatic dishwasher according to claim 1 or 2, wherein (c) is at least one selected from polyoxyalkylene monoalkyl or monoalkenyl ether type nonionic surfactants and glycoside type nonionic surfactants. Agent composition.   (D) The liquid detergent composition for automatic dishwashers of any one of Claims 1-3 containing polyvalent carboxylic acid or its salt of molecular weight 400 or less.