JP5890193B2 - Powder cleaning composition for automatic cleaning machine - Google Patents

Description

  The present invention relates to a powder cleaning composition used in an automatic cleaning machine for cleaning hard articles. More particularly, the present invention relates to a powder cleaning composition for an automatic cleaning machine used for cleaning hard articles such as kitchen utensils and plastic containers for food and beverage processing.

  Automatic washing machines are used for washing dishes such as dirty dishes, glasses and cooking utensils in kitchens such as homes, restaurants, and coffee shops, and washing plastic containers for foodstuffs and products used in food and beverage factories. . Main target soils include food-derived proteins, starches, oils and fats, and these soils are combined and adhered to dishes, glasses, tableware such as cooking utensils, and plastic containers. In addition, during cooking, these stains may be heat-denatured to become strong stains and be fixed. In particular, heat-denatured oil is a difficult-to-clean stain, and there is a need for a cleaning agent that removes this stain.

  Usually, the washing process by the automatic washing machine is performed in the order of washing and rinsing, but the time required for these processes is as short as about 40 to 60 seconds for the washing process and about 5 to 20 seconds for the rinsing process. It is.

  For this reason, alkali metal hydroxides, carbonates, and silicate alkali agents are used in powder detergent compositions for automatic washing machines in order to efficiently wash these strong stains in a short time. Has been. Among these alkali agents, alkali metal hydroxides are preferably used from the viewpoint of detergency. However, alkali metal hydroxides have deliquescent properties, so that handling properties are inferior, and when mixed with 5% or more, they are handled as deleterious substances, so there are restrictions on their use.

  In addition, tap water and well water containing hardness components such as Ca ions and Mg ions are often used for washing, and these hardness components and detergent-derived carbonate radicals, silicate radicals, and carbonates in the atmosphere are used. The gas reacts to form products such as calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate. Since this product is insoluble in water, it adheres to tableware, tanks of automatic washing machines, tank walls, etc., and forms a strong film called scale. As a result, it causes troubles such as a decrease in thermal efficiency of the heat exchange unit, blockage of the circulation pump, malfunction of the concentration sensor, and the like. In particular, while automatic dishwashers for general households are used only a few times a day, in commercial automatic washing machines used in kitchens such as restaurants and coffee shops, a day The continuous use is performed for several hours or more and several tens of times or more, and the adhesion of the scale is a big problem.

  In order to avoid troubles due to scale adhesion, phosphorus-type powder cleaners for automatic washing machines that contain tripolyphosphate, which is highly effective in suppressing scale adhesion, have been used. In view of environmental friendliness, it is a causative substance of nutrition, and development of a scale adhesion control technique equivalent to or higher than that of the phosphorus type is required in a phosphorus-free or very low amount of phosphate.

  As a technique for improving the effect of suppressing the adhesion of scale, Patent Document 1 discloses an automatic method having a predetermined particle size containing an alkali metal salt, a sequestering agent, a surfactant, an alkali metal carbonate, and a polymer electrolyte polymer. A detergent composition for a dishwasher is disclosed.

  On the other hand, it is also known to incorporate a chlorine bleach into a powder cleaning composition for an automatic cleaning machine. Patent Document 2 discloses a dishwashing containing an inorganic compound selected from silicates and carbonates, organic acid alkali metal salts, polyacrylic acid or salts thereof, maleic acid copolymers or salts thereof, and chlorine bleaching components. A machine cleaner composition is disclosed. Patent Document 3 discloses a tableware containing an inorganic compound having an anhydride content of 60% by mass or more selected from silicates and carbonates, chlorine bleach, tripolyphosphoric acid or a salt thereof, and a nonionic surfactant. A cleaning composition for a cleaning machine is disclosed. Patent Document 4 discloses a dishwasher cleaning composition containing a specific inorganic compound, a chlorine bleach, citric acid or a salt thereof, and a nonionic surfactant under predetermined conditions. Further, Patent Document 1 also describes that a chlorine bleach can be blended.

JP 2008-50410 A JP 2011-219527 A JP 2010-280796 A JP 2009-173704 A

  It is desired that a cleaning composition for an automatic cleaning machine in a powder form containing a chlorine bleach is excellent in the stability of the chlorine bleach in the cleaning composition. In addition, it is desired to have a high scale adhesion suppressing effect and a high detergency against heat-modified oil without substantially using an alkali metal hydroxide.

  The cleaning composition disclosed by Patent Document 1 is insufficient to achieve both a high detergency against heat-denatured oil and a high scale adhesion inhibiting effect. In addition, the cleaning composition disclosed in Patent Document 2 is desired to have higher cleaning properties against heat-denatured oil. With respect to the composition of Patent Document 3, a scale-free inhibitory effect and effective chlorine stability in a phosphorus-free system are desired. About the composition of patent document 4, the higher scale adhesion suppression effect is desired.

  An object of the present invention is to substantially eliminate alkali metal hydroxides in washing dishes such as dirty dishes, glasses and cooking utensils in kitchens, washing plastic containers for foods and products used in food and beverage factories, and the like. Even in the case of a phosphorus-free or very low phosphate compounding system, it has a high anti-scale adhesion effect and a high detergency against heat-denatured oil, and the chlorine-based bleaching agent in the detergent composition An object of the present invention is to provide a powder cleaning composition for an automatic cleaning machine for hard articles, which is excellent in stability.

The present invention
(A) A homopolymer of acrylic acid and a salt thereof, and at least one polymer selected from a copolymer of acrylic acid and maleic acid and a salt thereof (hereinafter referred to as component (a)) is 8 to 44.9% by mass,
(B) 15 to 56.9% by mass of a silicate [hereinafter referred to as component (b)] selected from an alkali metal metasilicate and an alkali metal orthosilicate
(C) 25-66.9% by mass of an alkali metal carbonate (hereinafter referred to as component (c)),
(D) 10-50% by mass of an alkali metal salt of citric acid (hereinafter referred to as component (d)), and
(E) dichloroisocyanuric acid and / or a salt thereof (hereinafter referred to as (e) component) is 0.1 to 10% by mass
A powder cleaning composition for an automatic cleaning machine for hard articles containing
The mass ratio (b) / (c) of the component (b) to the component (c) is 0.5 to 2.3,
The water content is 5% by mass or less,
The present invention relates to a powder cleaning composition for an automatic cleaning machine for hard articles.

  In the present invention, the powder cleaning composition for an automatic cleaning machine for hard articles means a powder cleaning composition used for cleaning hard articles such as dishes, cooking utensils, and plastic containers with an automatic cleaning machine.

  According to the present invention, there is a high detergency to heat-denatured oil and a high scale adhesion inhibitory effect without substantially using an alkali metal hydroxide, and the stability of the chlorine bleach in the detergent composition. Provided is a powder cleaning composition for an automatic cleaning machine for hard articles, which has excellent properties.

<(A) component>
From the viewpoint of detergency and scale suppression, the powder cleaning composition for an automatic cleaning machine of the present invention includes, as component (a), a homopolymer of acrylic acid and a salt thereof, and a copolymer of acrylic acid and maleic acid and a salt thereof. 1 or more types of polymers chosen from these are contained. Examples of homopolymers of acrylic acid and salts thereof include polyacrylic acid, sodium polyacrylate, potassium polyacrylate, and the like. Sodium polyacrylate and potassium polyacrylate are preferred, and a copolymer of acrylic acid and maleic acid and its Examples of the salt include a copolymer of acrylic acid and maleic acid, a sodium salt of a copolymer of acrylic acid and maleic acid, a potassium salt of a copolymer of acrylic acid and maleic acid, a sodium salt of a copolymer of acrylic acid and maleic acid, an acrylic acid The potassium salt of a copolymer of acid and maleic acid is preferred. The molar ratio of the copolymer of acrylic acid and maleic acid is preferably 99/1 to 1/99, more preferably 90/10 to 10/90, as the number of moles of acrylic acid / number of moles of maleic acid.

  The component (a) of the present invention is a monomer other than acrylic acid and maleic acid and can be copolymerized with acrylic acid and / or maleic acid as long as the effects of the present invention are not hindered. It may be a copolymer. Examples of monomers other than acrylic acid and maleic acid that can be copolymerized with acrylic acid and / or maleic acid include vinyl monomers, acrylic monomers, styrene monomers, and more specifically methacrylic monomers. Examples include acid, methyl acrylate, ethyl acrylate, methyl methacrylate, and styrene. The molar ratio in the component (a) of the monomer other than acrylic acid and maleic acid, which can be copolymerized with acrylic acid and / or maleic acid, is the property of the present invention, such as water solubility and the like. Although it will not be limited if it does not influence on expression of an effect, 0-5 mol% is preferable in (a) component, 0-3 mol% is more preferable, and it is most preferable that it is 0 mol%. Therefore, the homopolymer of acrylic acid and its salt of the present invention, and the copolymer of acrylic acid and maleic acid and its salt are monomers other than acrylic acid and maleic acid among all the constituent monomers, and are acrylic acid and / or It may be a polymer or copolymer containing a monomer copolymerizable with maleic acid in the range of 0 to 5 mol%.

  Usually, maleic anhydride is used in the copolymerization reaction for producing the component (a), and therefore, the above molar ratio may be a molar ratio based on maleic anhydride.

  In addition, the weight average molecular weight of the component (a) is preferably 1,000 to 100,000, more preferably 2,000 to 90,000, from the viewpoint of the scale adhesion inhibiting effect. This weight average molecular weight is obtained by using polyacrylic acid (for example, sigma Aldrich molecular weight standard reagent) was obtained as a standard substance.

<(B) component>
The powder cleaning composition for an automatic cleaning machine of the present invention contains a silicate selected from an alkali metal metasilicate and an alkali metal orthosilicate as the component (b). Examples of the component (b) include sodium metasilicate, potassium metasilicate, sodium orthosilicate, and potassium orthosilicate, and sodium orthosilicate and sodium metasilicate are preferable from the viewpoint of blending stability. From the viewpoint of further improving the stability of dichloroisocyanuric acid and / or a salt thereof which is the component (e) of the present invention, the component (b) is preferably an anhydride.

As the component (b) of the present invention, generally available alkali metal metasilicates and alkali metal orthosilicates can be used, but the molar ratio of the constituent silicic acid and alkali metal oxide is ( As the number of moles of silicic acid / (number of moles of alkali metal oxide), 0.3 to 1.2 is preferable, and more preferably 0.5 to 1.0. When component (b) is sodium orthosilicate or sodium metasilicate, the molar ratio of (number of moles of SiO ₂ ) / (number of moles of Na ₂ O) is preferably 0.3 to 1.2. Preferably, it is 0.5 to 1.0.

<(C) component>
The powder cleaning composition for an automatic cleaning machine of the present invention contains an alkali metal carbonate as the component (c). (C) As a component, sodium carbonate, potassium carbonate, sodium hydrogencarbonate, potassium hydrogencarbonate etc. are mentioned, Sodium carbonate and potassium carbonate are preferable from a viewpoint of detergency. In the present invention, sodium carbonate and potassium carbonate may be used in combination as the component (c). When sodium carbonate and potassium carbonate are used in combination, the mass ratio of sodium carbonate to potassium carbonate is not particularly limited, but is preferably 1-10 as (mass of sodium carbonate) / (mass of potassium carbonate), more preferably 2-5. preferable. From the viewpoint of further improving the stability of dichloroisocyanuric acid and / or a salt thereof which is the component (e) of the present invention, the component (c) is preferably an anhydride.

<(D) component>
The powder cleaning composition for an automatic cleaning machine of the present invention contains an alkali metal salt of citric acid as the component (d) from the viewpoint of cleaning properties and a scale adhesion inhibiting effect. Examples of the alkali metal salt of citric acid include trisodium citrate and tripotassium citrate. Trisodium citrate is preferred. From the viewpoint of further improving the stability of dichloroisocyanuric acid and / or a salt thereof which is the component (e) of the present invention, the component (d) is preferably an anhydride.

<(E) component>
(E) It contains dichloroisocyanuric acid and / or a salt thereof (hereinafter referred to as component (e)). Examples of the salt of dichloroisocyanuric acid include sodium salts.

<Powder cleaning composition for automatic cleaning machine>
The powder cleaning composition for an automatic cleaning machine of the present invention contains the above components (a) to (e), and may further contain other components.

  Content of (a) component in the powder cleaning composition for automatic washing machines of this invention is 8-44.9 mass% from a viewpoint of a scale adhesion inhibitory effect and cost. 10 mass% or more is preferable from a viewpoint of a washability and a scale adhesion inhibitory effect. Moreover, from a viewpoint of cost, 40 mass% or less is preferable, and 30 mass% or less is more preferable.

  Moreover, content of the (b) component in the powder cleaning composition for automatic washing machines of this invention is 15-56.9 mass%. From the viewpoint of detergency, the lower limit is 15% by mass or more, preferably 17% by mass or more, and more preferably 19% by mass or more. The upper limit is 56.9% by mass or less, preferably 50% by mass or less, and more preferably 40% by mass or less from the viewpoint of the scale adhesion inhibiting effect.

  Moreover, content of the (c) component in the powder cleaning composition for automatic washing machines of this invention is 25-66.9 mass% from a viewpoint of detergency. The upper limit is preferably 50% by mass or less, and more preferably 40% by mass or less, from the viewpoint of the scale adhesion inhibiting effect.

  Moreover, content of the (d) component in the powder cleaning composition for automatic washing machines of this invention is 10-50 mass% from a viewpoint of a scale adhesion inhibitory effect. 20-40 mass% is preferable from a viewpoint of a scale adhesion inhibitory effect, and 20-30 mass% is more preferable.

  Moreover, content of the (e) component in the powder cleaning composition for automatic washing machines of this invention is 0.1-10 mass%. From a viewpoint of a bleaching effect, 0.5-10 mass% is preferable, and 1-5 mass% is more preferable.

  Further, the water content in the powder cleaning composition for an automatic cleaning machine of the present invention is 5% by mass or less. (E) 4 mass% or less is preferable from a viewpoint of stability of a component, 3 mass% or less is more preferable, 2 mass% or less is further more preferable, and 1 mass% or less is still more preferable. This amount of water is the amount of water in the composition, and is the total amount of water present in the composition in the form of free water (free water), dissolved water, bound water, hydrated water and the like. The water content may be measured by any method as long as it can measure the amount of water present in the composition in these embodiments. For example, it can be measured by the Karl Fischer method (JIS K 0068). Moreover, when the water content can be calculated from the blended raw material, the value may be adopted. In addition, about the compound (hydrate) which contains hydration water, such as (b) component and (d) component, let the quantity including the hydration water be the quantity of those compounds.

  Moreover, as for the powder cleaning composition for automatic washing machines of this invention, mass ratio (b) / (c) of content of (b) component and content of (c) component is 0.5-2.3. It is. From the viewpoint of detergency, it is preferably 0.5-2, more preferably 0.6-1.5, and even more preferably 0.65-1.

  In addition, the total content of the component (b) and the component (c) in the powder cleaning composition for an automatic cleaning machine of the present invention is preferably 40 to 60% by mass from the viewpoint of detergency, and 45 to 55% by mass. Is more preferable.

  In the powder cleaning composition for an automatic cleaning machine of the present invention, the mass ratio of the content of the component (a) and the total content of the components (b) and (c) [(b) + (c) ] / (A) is preferably 3 to 10 and more preferably 5 to 8 from the viewpoints of detergency and scale suppression.

  In addition, the total content of the component (a) and the component (d) in the powder cleaning composition for an automatic cleaning machine of the present invention is preferably 30 to 50% by mass from the viewpoint of an effect of suppressing the scale adhesion. % By mass is more preferable, and 35 to 40% by mass is even more preferable.

  In addition to the components (a) to (e), the powder cleaning composition for an automatic cleaning machine of the present invention, if necessary, mirabilite, surfactant, enzyme, antifoaming agent, antiseptic, rust inhibitor, Bactericides, antibacterial agents, pigments, fragrances, hydrotropes and the like can be blended.

  Moreover, the powder cleaning composition for automatic washing machines of this invention can also contain organic chelating agents other than (d) component [henceforth (d ') component]. As component (d ′), (d′ 1) aminocarboxylates such as trisodium methylglycine diacetate and tetrasodium L-glutamate diacetate, (d2) hydroxycarboxylates such as disodium malate and sodium tartrate And one or more selected from the group consisting of trisodium methylglycine diacetate and tetrasodium L-glutamate diacetate are preferable. In the case where the component (d ′) is contained, the content in the composition is preferably 10 to 50% by mass, more preferably 20 to 40% by mass, and more preferably 20 to 30% by mass from the viewpoint of the effect of suppressing the scale adhesion. .

  As the surfactant blended in the powder cleaning composition for an automatic cleaning machine of the present invention, a nonionic surfactant, an anionic surfactant, a cationic surfactant, or an amphoteric surfactant may be used depending on the purpose. However, a nonionic surfactant is preferable from the viewpoint of detergency.

  Nonionic surfactants that can be used in the present invention are not particularly limited. For example, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, polyoxyalkylene dialkyl ether, polyoxyethylene alkenyl ether, polyoxyethylene Alkylene alkyl phenyl ether, Pluronic block polymer, Tetronic block polymer, Reverse pluronic block polymer, Reverse tetronic block polymer, Sucrose fatty acid ester, Sorbitan fatty acid ester, Polyethylene glycol fatty acid ester, Glycerin fatty acid ester, Polyglycerin fatty acid ester , Propylene glycol fatty acid ester, polypropylene glycol fatty acid ester, coconut fatty acid die Nolamide, lauric acid diethanolamide, lauric acid mytilinic acid diethanolamide, myristic acid diethanolamide, oleic acid diethanolamide, palm kernel fatty acid diethanolamide, alkyl glucosides, amine oxides, etc., especially from the viewpoint of detergency Polyoxyethylene polyoxypropylene alkyl ethers, pluronic block polymers, tetronic block polymers, reverse pluronic block polymers, and reverse tetronic block polymers are preferred. These nonionic surfactants may be used alone or in combination of two or more.

  The content of the nonionic surfactant is preferably from 0.1 to 10% by mass, and more preferably from 0.5 to 5% by mass from the viewpoint of the balance between detergency and other components and economic efficiency.

  The powder cleaning composition for an automatic cleaning machine of the present invention is used in an automatic cleaning machine for hard articles. Here, the hard article is an article mainly including a member having a hard surface, and includes an article having a size, shape, and material suitable for cleaning by an automatic washing machine. Moreover, the soft member may be partially contained. Specific examples of the hard article include tableware, cooking utensils, and plastic containers. Moreover, the automatic washing machine can use suitably the apparatus suitable for the automatic washing | cleaning of these hard articles. Moreover, the automatic washing machine can use suitably the apparatus suitable for the automatic washing | cleaning of these hard articles.

  Moreover, the powder cleaning composition for automatic washing machines of this invention can be made into what is called a phosphorus-free type composition which does not contain the compound containing phosphorus.

  The powder cleaning composition for an automatic cleaning machine of the present invention has a pH (JIS K 3362) at 25 ° C. of a 0.1% by weight aqueous solution of 10 to 13, more preferably 11 to 12, indicating that the cleaning property and the substrate It is preferable from the viewpoint of damage.

  A powder cleaning composition for an automatic cleaning machine having the composition shown in Table 1 was prepared, and the scale adhesion inhibiting ability, cleaning ability, and effective chlorine residual ratio were evaluated by the following methods. The results are shown in Table 1. In Table 1, the pH at 25 ° C. of a 0.1% by mass aqueous solution of the composition was measured according to JIS K 3362 and is also shown.

[1] Evaluation of scale inhibition ability <Test conditions>
Washing machine used: Automatic dishwasher (SANIJET SD113EA6) manufactured by Nippon Washing Machine Co., Ltd.
Washing temperature: 65 ° C
Cleaning time: 40 seconds Rinsing temperature: 85 ° C
Rinsing time: 10 seconds Cleaning concentration: 0.10% by mass
Water used: 6 ° dH hard water (adjusted with calcium chloride)

<Evaluation method>
Ten test pieces (100 mm × 130 mm) of SUS304 were placed in a washing rack, and after washing, rinsing and air drying at room temperature 1000 times under the above test conditions, the appearance of the test piece was evaluated according to the following evaluation criteria. Was visually determined. Table 1 shows the average value of 10 sheets.

<Evaluation criteria>
6: Glossy with no difference compared to before test 5: Slightly discolored but no scale attached, glossy 4: Discolored but no scale adhered, glossy 3: Part of the scale is attached, but glossy 2: The whole is covered with scale, and there is no gloss 1: The whole is covered with scale, and there is no gloss and the surface is rough. Is preferably 4 points or more that are judged to be glossy.

[2] Evaluation of detergency <Preparation of heat-denatured oil>
500 g of rapeseed oil was put into a 1 L four-necked flask, stirred and mixed at 180 ° C. for 15 hours while blowing air at a flow rate of 2 L / min, and cooled at 25 ° C. for 24 hours to obtain heat-modified oil. To this heat-denatured oil, 0.1% of Sudan IV was added and colored red.

<Production of model dirt>
The above-mentioned colored heat-denatured oil (5 g) was uniformly applied in a circular shape having a diameter of about 10 cm with a brush to the center of a new 20 cm diameter polypropylene dish, and used as a model soil for evaluation of the cleaning property.

<Evaluation method>
62 g of the powder cleaning composition for an automatic washing machine shown in Table 1 was put into a washing tank (62 L) of an automatic dishwashing machine (SANIJET SD113EA6) manufactured by Nippon Washing Machine Co., Ltd. and dissolved in warm water at 65 ° C. Four polypropylene dishes coated with model dirt were set on a dedicated rack, washed with a cleaning solution at 65 ° C. for 45 seconds, and then rinsed with 85 ° C. rinsing water for 10 seconds. The polypropylene dish was taken out from the dedicated rack, and the washability was visually judged by 10 researchers according to the following criteria, and the score was averaged to give an evaluation score.

<Criteria for cleaning performance>
7: No staining marks are observed on any of the four polypropylene dishes, and the dirt is removed. 6: Most stains are observed only on one of the four polypropylene dishes. 5; Most of the stains are removed to the extent that a slight coloring mark is observed on two of the four polypropylene dishes. 4; A slight coloring mark is shown on three of the four polypropylene dishes. Most of the dirt has been removed 3); almost all the dirt has been removed to the extent that slight staining marks are observed on all four polypropylene dishes 2; all four polypropylene dishes have been removed Color marks are observed, and about half of the dirt remains; all four polypropylene dishes have color marks, and most of the dirt remains. If the score is 5 or more Good.

[3] Evaluation of Effective Chlorine Residual Rate The cleaning composition is filled with 2 kg of a bag-like container (material: nylon / PET laminate film) and shape (flat bag, capacity of about 3 L) and sealed, at 40 ° C., The effective chlorine concentration after storage for 30 days at a relative humidity of 80% was measured, and the effective chlorine residual rate after storage was determined from the initial effective chlorine concentration. This evaluation is an evaluation of storage stability assuming storage in the form of a pouched product.
Effective chlorine residual rate (%) = (effective chlorine concentration after storage / initial effective chlorine concentration) × 100
The effective chlorine residual rate is preferably 60% or more, and more preferably 70% or more.

-Sodium polyacrylate: weight average molecular weight 4,000, Socaran PA25CL Granules (manufactured by BASF Japan Ltd., effective content 92 mass%, water content 8 mass%) [Raw material information is from BASF Japan Ltd. product catalog. The mass% in a table | surface is based on the compounding quantity with a product presence. ]
Acrylic acid-maleic acid copolymer: sodium salt [acrylic acid / maleic acid (molar ratio) = 70/30, weight average molecular weight = 70,000, effective content 92 mass%, water content 8 mass%]
Nonionic surfactant: propylene oxide / ethylene oxide / propylene oxide / block polymer [weight average molecular weight 3,100, propylene oxide / ethylene oxide ratio = 80/20, Pluronic RPE 2520 (manufactured by BASF Japan Ltd.): raw material information is BASF Japan According to the product catalog. The mass% in a table | surface is based on the compounding quantity with a product presence. ]
-Sodium metasilicate-Anhydrous salt: SiO ₂ / Na ₂ O molar ratio 1.0
Sodium metasilicate pentahydrate: SiO ₂ / Na ₂ O molar ratio 1.0
- sodium metasilicate · nonahydrate: SiO ₂ / Na ₂ O molar ratio 1.0

Claims (7)

(A) A homopolymer of acrylic acid and a salt thereof, and at least one polymer selected from a copolymer of acrylic acid and maleic acid and a salt thereof (hereinafter referred to as component (a)) is 8 to 44.9% by mass,
(B) 15 to 56.9% by mass of a silicate [hereinafter referred to as component (b)] selected from an alkali metal metasilicate and an alkali metal orthosilicate
(C) 25-66.9% by mass of an alkali metal carbonate (hereinafter referred to as component (c)),
(D) 10-50% by mass of an alkali metal salt of citric acid (hereinafter referred to as component (d)), and
(E) dichloroisocyanuric acid and / or a salt thereof (hereinafter referred to as (e) component) is 0.1 to 10% by mass
Containing
The mass ratio (b) / (c) of the component (b) to the component (c) is 0.5 to 2.3,
The water content is 4 % by mass or less,
A powder cleaning composition for an automatic cleaning machine for hard articles.   2. The powder cleaning composition for an automatic cleaning machine for hard articles according to claim 1, wherein the total content of the component (b) and the component (c) is 40 to 60% by mass.   The powder cleaning composition for an automatic cleaning machine for hard articles according to claim 1 or 2, wherein the component (b) is an anhydride.   (C) Component is an anhydride, The powder cleaning composition for automatic washing machines of the hard article of any one of Claims 1-3.   The total content of the component (a) and the component (d) is 30 to 50% by mass. The powder cleaning composition for an automatic cleaning machine for hard articles according to any one of claims 1 to 4.   (D) Component is an anhydride, The powder cleaning composition for automatic washing machines of the hard article in any one of Claims 1-5.   (D) A component is trisodium citrate, The powder cleaning composition for automatic washing machines of the hard article of any one of Claims 1-6.