WO2008021971A1

WO2008021971A1 - Method for supplying detergent to automatic washing machine, tablet detergent composition for automatic washing machine used therefor, and washing method using same

Info

Publication number: WO2008021971A1
Application number: PCT/US2007/075610
Authority: WO
Inventors: Takashi Yamazaki
Original assignee: JohnsonDiversey Inc
Current assignee: Diversey Inc
Priority date: 2006-08-10
Filing date: 2007-08-09
Publication date: 2008-02-21
Anticipated expiration: 2009-02-10
Also published as: JP2008044972A; JP5207161B2

Abstract

The present invention provides a method capable of supplying a detergent solution of a stable concentration to an automatic washing machine by using a detergent supply apparatus of inexpensive structure; a tablet detergent composition for an automatic washing machine that is used in the method and that excels in a dissolution characteristic, washing characteristic, storage characteristic and the like; and a washing method using the composition. A tablet detergent composition comprising (A) a metal salt of a saturated fatty acid, (B) a silicate, (C) an aminocarboxylic acid salt, and (D) a nonionic surfactant as essential components at specific content ratios is accommodated inside a casing of a detergent supply apparatus disposed in an automatic washing machine. Washing water or rinsing water sprayed inside the automatic washing machine is brought into contact with the tablet detergent composition, and a detergent solution of a high-concentration that has been dissolved is caused to flow into a washing tank of the automatic washing machine, and washing water of a desired concentration is prepared and supplied to wash the articles to be washed.

Description

METHOD FOR SUPPLYING DETERGENT TO AUTOMATIC WASHING MACHINE,

TABLET DETERGENT COMPOSITION FOR AUTOMATIC WASHING MACHINE

USED THEREFOR, AND WASHING METHOD USING SAME

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for supplying a detergent to an automatic washing machine suitable for washing hard surfaces such as metals, glass, ceramics, and plastics, to a tablet detergent composition for an automatic washing machine used in such method, and to a washing method using the same .

2. Description of the Related Art

Automatic dishwashing machines have been widely used for efficiently washing used dishes in hotels, restaurants, catering companies, hospitals, company cafeterias, and the like. Further, automatic washing machines have been used for washing not only dishes, but also food-related products such as utensils, vessels, trays, and containers in a variety of food production plants and food processing plants. In these automatic washing machines, powder detergents or liquid detergents have been supplied by appropriate detergent supply methods corresponding to the shape of the detergent.

For example, in the case of powder detergents, a washing operator takes a necessary amount of detergent from a detergent container and directly loads the detergent into the apparatus for supplying a detergent, or a plastic cartridge filled with 2 to 5 kg of detergent and having a mesh cap on the upper surface is loaded inversely into an apparatus for supplying a detergent, water is sprayed inside the cartridge, and the detergent is gradually dissolved. With the method by which the detergent is directly loaded, if the detergent is not handled correctly due to poor operation efficiency, there is a risk of the detergent with a large alkali content adhering to skin or a powdered detergent being inhaled. Further, although a cartridge-type powdered detergent is free from the risk of coming into direct contact with a human body, the powdered detergent is sometimes solidified under the effect of water sprayed inside the cartridge and solubility thereof is degraded. Yet another problem is that spread in dissolution rate can occur due to a difference in particle size distribution between the detergent components, the detergent solution of constant composition cannot be obtained, and the washing effect can vary.

Further, in the case of liquid detergents, because the detergent is directly supplied for use into the washing tank, the detergent does not come into direct contact with human body. In addition, because a detergent composition (starting solution) of a high concentration is prepared in advance, solubility with a high degree of uniformity can be obtained. However, because the amount of effective components in liquid detergents is lower than that in the powdered detergents, the liquid detergents are contained in thick polyethylene containers of a capacity (for example, 5 to 20 L) much larger than that of the containers for powdered detergents. As a result, problems arise when the containers are discarded.

On the other hand, in addition to powdered and liquid detergents, solid cartridge-type detergents have been suggested and actually marketed. Similarly to powdered cartridge-type detergents, such solid cartridge-type detergents are loaded reversely into a supply device during use, the detergent is dissolved from the surface thereof by hot water sprayed on the detergent surface from below, and the solution produced is supplied into a washing tank. However, because solid detergents manufactured by melt injection and solidification process have poor solubility, at an initial stage at which a detergent is again supplied to an automatic washing machine after a long time elapses since the completion of a washing operation, the necessary amount of detergent is not dissolved within a short interval and the detergent concentration is sometimes insufficient. Further, at certain temperature and pressure of water used to dissolve the detergent, undissolved detergent remains on the inner wall of container and handling at the time of discarding is sometimes difficult. Further, because thick plastic containers ensuring high safety are used for solid- cartridge-type detergents to enable the injection of high-concentration alkaline detergent compositions melted at 60 to 65°C, the production cost is high and problems are encountered when plastic containers are di scarded .

Further, when such powdered, liquid and solid cartridge- type detergents are supplied in the automatic dishwashing machine, because an apparatus for supplying a detergent using a concentration control method based on electric conductivity is employed, an electric conductivity sensor, an electromagnetic valve, a control device therefor, and a hose are necessary. As a result, problems are associated with ensuring the installation space for the apparatus for supplying a detergent and controlling the cost of the apparatus for supplying a detergent ,

Accordingly, a variety of detergents , methods for supplying a detergent into an automatic washing machine, and apparatuses for supplying a detergent have been suggested to resolve the above-mentioned problems inherent to the powdered, liquid, and solid cartridge-type detergents.

For example, a tablet detergent comprising tripolyphosphoric acid hexahydrate, an antifoaming surfactant, a polycarboxylate, and propylene glycol and making it possible to obtain a uniform dissolution rate {see Japanese Patent Publication Tokuhyo No. 9-503799) , a tablet-type detergent composition for an automatic dishwashing machine that is obtained by compression molding a group of particles including surfactant-containing particles and sugar alcohol-containing particles, demonstrates rapid solubility and sufficient detergent effect, and causes no adhesion of insolubles to dishes in any automatic dishwashing machine (see Japanese Patent Application Laid-open No. 2004-211073) , and a detergent tablet comprising an alkali metal metasilicate, a pentaalkali metal triphosphate, a chlorine compound, and a tableting enhancer and having uniform composition and wide-range solubility distribution (see Japanese Patent Application Published No. 4-55639) have been suggested.

Further, a detergent pack for dishwashing machines in which a granulated detergent is sealed in a non-wettable flexible film, and a large number of detergent elution holes that are less in size than the detergent granules are provided in the film surface (see Japanese Patent Application Laid-open No. 10-94511), and an apparatus for supplying a detergent in which a detergent that circulates inside a washing machine is taken in via an open section or hole provided in a lid covering the top of a container accommodating the detergent and the detergent is dissolved and supplied into the washing tank via a slit or hole provided in the side portion or bottom portion of the container (see Japanese Patents No. 3300347 and 3487695) have been suggested.

Further, an apparatus for supplying a detergent in which a washing water is taken in from an open section or a hole provided in the top portion of the apparatus and the detergent is dissolved and supplied into a washing tank via a slit or a through hole provided in the side portion of the apparatus, or the washing water overflows from the open section through which it is introduced and the dissolved washing solution is supplied into the washing tank has also been suggested (Japanese Patent Applications Laid-open No. 2002-10963 and 2003-10093) .

SUMMARY OF THE INVENTION

However, although the detergent described in Japanese Patent Publication Tokuhyo No. 9-503799 can maintain a constant dissolution rate due to a tablet shape thereof, the problem is that an expensive apparatus for supplying a detergent is necessary to supply such detergent into an automatic washing machine.

Further, when the detergents described in Japanese Patent Application Laid-open No. 2004-211073 and Japanese Patent Application Published No. 4-55639 are used in a system in which the detergent is charged for each single washing step, as in a household automatic dishwashing machine, solubility of the detergent can be controlled and the detergent can demonstrate a sufficient effect. On the other hand, where the tablet detergents are used in commercial automatic dishwashing machines, the detergent solution is prepared in a batch mode in a large-capacity washing tank and the detergent corresponding in quantity to the rinsing water flowing into the washing tank in the washing process has to be loaded in each operation cycle of the washing machine to maintain a constant concentration of detergent solution, this loading being a time-consuming and troublesome operation. Moreover, because the washing time in automatic dishwashing machines is shorter than that in household automatic dishwashing machines, the detergent cannot be completely dissolved within the washing interval and the detergent concentration is unstable. As a result, the detergent is unsuitable for commercial automatic dishwashing machines.

Further, in the detergent supply pack described in Japanese Patent Application Laid-open Mo, 10-94511, the detergent is in the form of granules and the detergent is sealed in a non-wettable flexible film having detergent elution holes. The pack is expanded or shrunk by using water pressure of washing water and a small amount of the detergent converted into a sol can be caused to elute only within the necessary interval through the detergent elution holes, thereby enabling the use of one pack for a several dishwashing cycles. The advantage of such pack is that the operation of loading the detergent for washing is facilitated and washing operation can be performed with good efficiency. However, the drawback is that when the type or washing conditions of automatic dishwashing machine are changed, the amount of dissolved detergent can be too large or insufficient and the concentration of detergent in the washing tank of the automatic dishwashing machine cannot be controlled to a desired level. In particular, the amount of detergent contained in the pack decreases gradually during use, and because the amount of the eluted detergent also changes according to the changes in the detergent amount, the detergent concentration is very difficult to maintain at a constant level at all times .

On the other hand, because the apparatuses described in Japanese Patents No. 3300347 and 3487695 are not provided with a function of adjusting the quantity of washing liquid flowing into the apparatus from an open section, the resultant drawback is that when the type or washing conditions of automatic dishwashing machine are changed, the amount of dissolved detergent can be insufficient and the concentration of detergent in the washing tank of the automatic dishwashing machine cannot be controlled to a desired level.

Further, the merit of the apparatuses described in Japanese Patent Applications Laid-open No. 2002-10963 and 2003-10093 is that the amount of dissolved detergent can be controlled by adjusting the opening degree of the open section or hole provided in the top section of the apparatus. However, the problem associated with the dissolved quantity changing according to the variations in the amount of detergent charged into the apparatus cannot be resolved.

The present invention was created with the foregoing in view and it is an object thereof to provide a method for supplying a detergent solution of stable concentration into an automatic washing machine by using an apparatus for supplying a detergent of inexpensive configuration, a tablet detergent composition for an automatic dishwashing machine that employs the aforementioned method and demonstrates excellent dissolution characteristic, washing characteristic, and storage characteristic, and a washing method using the tablet detergent composition.

In order to attain the above-described object, in accordance with the first gist of the present invention, there is provided a method for supplying a detergent to an automatic washing machine, comprising the steps of disposing inside the automatic washing machine an apparatus for supplying a detergent comprising a casing accommodating a tablet detergent composition having the following (A) to (D) components as essential components, and an open section for bringing washing water or rinsing water sprayed inside the automatic washing machine into contact with the tablet detergent composition located inside the casing and for causing the diluted detergent to flow out; causing gradual dissolution of the tablet detergent composition located inside the casing by the washing water or rinsing water sprayed inside the automatic washing machine; and causing a detergent solution of a high- concentration that has been thus dissolved to flow into a washing tank of the automatic washing machine, preparing washing water of a desired concentration, and supplying the prepared washing water to wash articles to be washed:

(A) a metal salt of a saturated fatty acid: 0.01 to 3 wt . % ;

(B) a silicate: 10 to 60 wt . % ; (C) an aminocarboxylic acid salt: 10 to 60 wt.%; and

(D) a nonionic surfactant: 0.1 to 5 wt.%.

In accordance with the second gist of the present invention, there is provided the above-described method for supplying a detergent to an automatic washing machine wherein the automatic washing machine is an automatic dishwashing machine .

In accordance with the third gist of the present invention, there is provided a tablet detergent composition for an automatic washing machine that is used in the method for supplying a detergent to an automatic washing machine according to the above first or second gist, the composition having the following (A) to (D) components as essential components :

(A) a metal salt of a saturated fatty acid: 0.01 to 3 wt . % ;

(B) a silicate: 10 to 60 wt.%;

(C) an aminocarboxylic acid salt: 10 to 60 wt.%; and

(D) a nonionic surfactant: 0.1 to 5 wt.%.

In accordance with the fourth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein the metal salt of a saturated fatty acid, which is the (A) component, is a metal salt of a fatty acid having 8 to 22 carbon atoms, and in accordance with the fifth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein the silicate, which is the (B) component, is at least one of an alkali metal metasilicate and a metal orthosilicate .

In accordance with the sixth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein the aminocarboxylic acid salt, which is the (C) component, is at least one of an ethylene diaminetetraacetate and nitrilotriacetate, and in accordance with the seventh gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein the nonionic surfactant, which is the (D) component, is a combination of (a) polyoxyethylene - polyoxypropylene alkyl ether and (b) at least one of an ethylene oxide - propylene oxide adduct of trimethylolpropane and an ethylene oxide - propylene oxide adduct of glycerin.

In accordance with the eighth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein the nonionic surfactant, which is the (D) component, is a combination of at least one of (a) and (b) according to claim 7 and (c) at least one of 2 , 4 , 7 , 9-tetramethyl-5-decyne-4 , 7- diol and polyoxyethylene acetylenic glycol ether, or derivatives or isomers thereof, the (c) being contained at 0.1 to 3 wt .% based on the entire detergent composition.

In accordance with the ninth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein a washing builder comprising at least one of a carbonate, a sulfate, and a bicarbonate is contained as an (E) component at

5 to 70 wt .% based on the entire detergent composition together with the (A) to (D) components, and in accordance with the tenth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein a high-molecular electrolyte polymer is contained as an (F) component at 0.1 to

6 wt .% based on the entire detergent composition together with the (A) to (D) components.

In accordance with the eleventh gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein a chlorine bleaching agent is contained as a (G) component at 0.1 to 4 wt .% based on the entire detergent composition together with the (A) to (D) components, and in accordance with the twelfth gist of the present invention, there is provided the above-described tablet detergent composition for an automatic washing machine wherein talc is contained as an (H) component at 0.1 to 5 wt . % based on the entire detergent composition together with the (A) to (D) components.

In accordance with the thirteenth gist of the present invention, there is provided a washing method comprising the steps of supplying a dissolved detergent to an automatic washing machine by the method for supplying a detergent to an automatic washing machine according to the above first or second gist, preparing washing water of a desired concentration inside a washing tank of the automatic washing machine, and using the prepared washing water for washing articles to be washed, and in accordance with the fourteenth gist of the present invention, there is provided the above- described washing method wherein the automatic washing machine is an automatic dishwashing machine.

Thus, with the method for supplying a detergent to an automatic washing machine in accordance with the present invention, a tablet detergent composition comprising specific components and having excellent uniform solubility is accommodated in a special apparatus for supplying a detergent of a type to be disposed inside an automatic washing machine, the apparatus for supplying a detergent is disposed inside an automatic washing machine, the tablet detergent composition is dissolved using washing water or rinsing water sprayed inside the automatic washing machine, and the resultant detergent solution is caused to flow into a washing tank of the automatic washing machine.

Therefore, with the method for supplying a detergent, the detergent composition can be evenly dissolved each time by intermittent contact between the washing water or rinsing water and the detergent composition, and concentration of the washing water prepared inside the washing tank can be maintained at a constant level .

The tablet detergent composition for an automatic washing machine used in accordance with the present invention demonstrates excellent tableting strength, does not break during transportation, and excels in washing performance, scale inhibition performance, and low foaming. Therefore, not only this tablet detergent composition is optimum for the method for supplying a detergent, but also makes it possible to obtain excellent washing effect at all times when washing is conduced with the detergent composition.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a schematic structural diagram illustrating an automatic dishwashing machine used in an embodiment of the present invention;

Fig. 2 is a view along A-A¹ arrow in Fig. 1;

Fig. 3 is an explanatory drawing of an apparatus for supplying a detergent used in the embodiment;

Figs. 4A and 4B are explanatory drawings illustrating modification examples of respective apparatuses for supplying a detergent;

Fig. 5 is a graph illustrating changes with time in concentration of the washing solution that is fed in an embodiment of the present invention;

Fig. 6 is a graph illustrating changes with time in concentration of the washing solution that is fed in another embodiment of the present invention; and Fig. 7 is a graph illustrating changes with time in concentration of the washing solution that is fed in yet another embodiment of the present invention.

DESCRIPTION QF THE PREFERRED EMBODIMENTS

The best mode for carrying out the invention will be described below in greater detail.

The tablet detergent composition for an automatic washing machine that is used in the method for supplying a detergent to an automatic washing machine in accordance with the present invention (abbreviated hereinbelow as "present detergent composition") contains the following (A) to (D) components as essential components :

(A) a metal salt of a saturated fatty acid;

(B) a silicate;

(C) an aminocarboxylic acid salt; and

(D) a nonionic surfactant .

The metal salt of a saturated fatty acid, which is the (A) component, is used to control solubility of the present detergent composition. It is especially preferred that a metal salt of a saturated fatty acids having 8 to 22 carbon atoms be used. Among such salts, metal salts of saturated fatty acids having 14 to 20 carbon atoms are preferred from the standpoints of lubrication performance during tableting and solubility control in automatic washing machines. Examples of such metal salts include calcium stearate, magnesium stearate, aluminum stearate, magnesium myristate, calcium myristate, aluminum myristate, magnesium palmitate, calcium palmitate, and aluminum palmitate. These salts may be used individually or in combinations of two or more thereof. Among then, calcium stearate and magnesium stearate are especially preferred from the standpoint of solubility control in automatic washing machines.

The compounding ratio of the (A) compound has to be set within a range of 0.01 to 3 wt . % based on the entire detergent composition. Thus, where the compounding ratio is less than 0.01 wt . % , the desired solubility control is lacking. On the other hand, a compounding ratio of more than 3 wt . % is unsuitable because strength of the tablet produced decreases and synergetic effect with other components and good stability in storage cannot be obtained. Setting this compounding ratio within a range of 0.05 to 2 wt . % is especially preferred from the standpoint of effect produced.

The silicate, which is the (B) component, is used to improve washing performance and contamination decomposition performance of the tablet detergent composition in accordance with the present invention. Silicates represented by Chemical Formula (1) below are especially preferred. From the standpoint of washing performance and contamination decomposition performance, silicates in which the below- described x : y is 1 : 2 to 3 : 1 are especially preferred. Examples of such silicates include sodium metasilicate, potassium metasilicate, sodium orthosilicate, potassium orthosilicate, sodium disilicate, potassium disilicate, layered sodium silicate, and layered potassium silicate; they can be used as anhydrous compounds or hydrates. They also may be used Individually or in combinations of two or more thereof From the standpoint of washing performance and balance with other components, sodium orthosilicate, potassium orthosilicate, sodium metasilicate, and potassium metasilicate are especially preferred. XM₂O • ySiO₂ ^■ zH₂O ... (1) (here, x, y are added mole numbers; z is 0 to 9) .

The compounding ratio of the (B) compound has to be set within a range of 10 to 60 wt . % based on the entire detergent composition. Thus, where the compounding ratio is less than 10 wt. %, the desired washing performance is lacking. On the other hand, a compounding ratio of more than 60 wt . % is unsuitable because the balance of the entire composition Is degraded and synergetic effect with other components of good stability in storage cannot be obtained. Setting this compounding ratio within a range of 15 to 35 wt . % is especially preferred from the standpoint of effect.

Examples of aminocarboxylic acid salt, which is the (C) component, include water-soluble alkali metal salts such as sodium salts and potassium salts, ethanolamine salts, and ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, iminodiacetic acid, diethylenetriaminepentaacetic acid, M-hydroxyethyl ethylenediaraineacetic acid, ethylenediaminetetrapropionic acid, methylglycinediacetic acid, triethylenetetraminehexaacetic acid, ethylene glycol diether diaminetetraacetic acid, hydroxyethyliminodiacetic acid, cyclohexane-1, 2- diaminetetracetic acid, and djenkolic acid, These compounds may be used individually or in combinations of two or more thereof .

Among these aminocarboxylic acid salts, sodium salt of ethylenediaminetetraacetic acid, potassium salt of ethylenediaminetetraacetic acid, sodium salt of nitrilotriacetic acid, and potassium salt of nitrilotriacetic acid are especially preferred, and from the standpoint of cost, sodium salts are especially preferred.

These water-soluble alkali metal salts of aminocarboxylic acids can be selected from commercial products, but for example, sodium salt of ethylenediaminetetraacetic acid can be appropriately prepared by adding sodium hydroxide (neutralization) to ethylenediaminetetraacetic acid. Thus, in the case of adding sodium hydroxide and potassium hydroxide, a mixture comprising sodium salt of ethylenediaminetetraacetic acid and potassium salt of ethylenediaminetetraacetic acid at any ratio can be obtained. Partial neutralization product can be also obtained.

The compounding ratio of the (C) compound has to be set within a range of 10 to 60 wt . % based on the entire detergent composition. Thus, where the compounding ratio is less than 10 wt. %, the desired washing performance is not demonstrated. On the other hand, a compounding ratio of more than 60 wt . % is unsuitable because the balance of the entire composition is degraded and also from the standpoint of cost and synergetic effect with other components. In terms of the effect produced, setting the compounding ratio within a range of 15 to 35 wt . % is especially advantageous.

Examples of suitable nonionic surfactant, which is the (D) component, include polyoxyethylene alkyl ethers, polyoxyethylene - polyoxypropylene alkyl ether, pluronic block polymers, reverse pluronic block polymers, ethylene oxide - propylene oxide adducts of polyhydric alcohols, and ethylene oxide - propylene oxide adducts of glycerin. These components are compounded with the object of improving washing ability, ability to prevent re-adhesion of oil of the article to be washed, and improvement of low-foaming ability. They may be used individually or in combinations of two or more thereof.

From the standpoint of the aforementioned washing performance, low- foaming ability, and ability to prevent re- adhesion of oil to the article to be washed, it is especially preferred that a combination of (a) polyoxyethylene - polyoxypropylene alkyl ethers and at least one of (b) ethylene oxide - propylene oxide adducts of trimethylolpropane and ethylene oxide - propylene oxide adducts of glycerin be used as the nonionic surfactant.

Examples of (a) polyoxyethylene - polyoxypropylene alkyl ethers include polyoxyethylene - polyoxypropylene alkyl ethers obtained by adding 1 to 40 mol ethylene oxide ("ethylene oxide" will be denoted hereinbelow by "EO" } and 1 to 50 mol propylene oxide ("propylene oxide" will be denoted hereinbelow by "PO") to a linear or branched alcohol having 6 to 24 carbon atoms. Examples of such compounds include those in which 1 to 20 mol EO and 1 to 20 mol PO are added to a linear or branched alcohol having 6 to 18 carbon atoms and the EO/PO weight ratio is within a range of 0.5 to 5, those in which 1 to 15 mol EO and 1 to 50 mol PO are added to a linear or branched alcohol having 6 to 18 carbon atoms and the EO/PO weight ratio is within a range of 0.05 to 1, and those in which 1 to 20 mol EO and 1 to 20 mol PO are added to a linear or branched alcohol having 6 to 18 carbon atoms and the EO/PO weight ratio is within a range of 0.5 to 5.

A compound obtained by adding 3 to 45 mol EO and 15 to 120 mol PO to trimethylolpropane is an example of ethylene oxide - propylene oxide adducts of trimethylolpropane (b-1) of compound (b) . A compound obtained by adding 3 to 45 mol EO and 15 to 120 mol PO to glycerin is an example of ethylene oxide - propylene oxide adducts of glycerin (b-2) representing one more example of compound (b) .

The (a) and (b) compounding ratio can be set appropriately, and it is preferred that this ratio be within a range of (a) : (b) = 9 : 1 to 5 : 5.

When the present detergent composition is applied to an automatic washing machine with a high pump water pressure that requires a better low- foaming performance, it is preferred that (c) at least one compound from among 2 , 4 , 7 , 9-tetramethyl- 5-decyne-4 , 7-diol and polyoxyethylene acetylenic glycol ether, or a combination of derivatives or isomers thereof be used as a nonionic surfactant, which is the (D) component, in combination with at least one from among the (a) and (b) described above. The number of added moles of polyoxyethylene in the polyoxyethylene acetylenic glycol ether is preferably 1 to 4, and from the standpoint of attaining the balance with other components and improving antifoaming ability, it is preferred that polyoxyethylene {1.3} acetylenic glycol ether (the number in the brackets (...) represents the number of the added moles) be used.

From the standpoint of washing performance and antifoaming ability, the following specific combinations of (a) , (b) , (c) are especially preferred.

(1) A combination of two components including (a) a polyoxyethylene - polyoxypropylene alkyl ether in which 1 to

20 mol EO and 1 to 20 mol PO are added to a linear or branched alcohol having 6 to 18 carbon atoms and the EO/PO weight ratio is within a range of 0.5 to 5 and (b~l) an ethylene oxide - propylene oxide adduct of trimethylolpropane (abbreviated hereinbelow as "polyhydric alcohol") obtained by adding 3 to 45 mol EO and 15 to 120 mol PO to trimethylolpropane.

(2) A combination of two components including (a) a polyoxyethylene - polyoxypropylene alkyl ether in which 1 to 20 mol EO and 1 to 20 mol PO are added to a linear or branched alcohol having 6 to 18 carbon atoms and the EO/PO weight ratio is within a range of 0.5 to 5 and (b-2) an ethylene oxide - propylene oxide adduct of glycerin obtained by adding 3 to 45 mol EO and 15 to 120 mol PO to glycerin.

(3) A combination of three components including (a) a polyoxyethylene - polyoxypropylene alkyl ether in which 1 to

20 mol EO and 1 to 20 mol PO are added to a linear or branched alcohol having 6 to 18 carbon atoms and the EO/PO weight ratio is within a range of 0.5 to 5, (b-1) an ethylene oxide - propylene oxide adduct of polyhydric alcohol obtained by adding 3 to 45 mol EO and 15 to 120 mol PO to trimethylolpropane, and (b-2) an ethylene oxide - propylene oxide adduct of glycerin obtained by adding 3 to 45 mol EO and 15 to 120 mol PO to glycerin.

(4) Combinations obtained by adding 2 ,4 , 7, 9-tetramethyl- 5-decyne-4, 7-diol and/or at least one polyoxyethylene acetylenic glycol ether of (c) as a nonionic surfactant to the above-described combinations (1) through (3) .

The compounding ratio of the nonionic surfactant that is the (D) compound has to be set within a range of 0.1 to 5 wt . % based on the entire present detergent composition.

Thus, where the compounding ratio is less than 0.1 wt . % , the desired washing performance is lost and low-foaming performance is not obtained. On the other hand, where the compounding ratio exceeds 5 wt.%, the balance of the entire composition is degraded, washing performance attained due to synergetic effective with other components is saturated, and such as addition is cost ineffective. Further, from the standpoint of the effect product it is especially preferred that this compounding ratio be set within a range of 0.5 to 3 wt.%.

When (c) is used as part of the (D) component, the compounding ratio thereof is preferably set within a range of 0.1 to 3 wt.% based on the entire present detergent composition. Thus, where the compounding ratio is less than 0.1 wt.%, there is a risk of losing the desired antifoaming performance, and where the compounding ratio exceeds 3 wt.%, the balance of the entire composition is degraded and the permeation effect with respect to contamination and the synergetic effect with other components reach a saturation level .

Further, in the present detergent composition, the below- described (E) a specific washing builder, (F) a high-molecular electrolyte polymer, (G) a chlorine bleaching agent, and (H) talc can be compounded as optional components with the (A) to (D) components, which are essential components.

Examples of the washing builder, which is the (E) component, is at least one carbonate, sulfate, and bicarbonate, specific examples including carbonates such as sodium carbonate and potassium carbonate, sulfates such as sodium sulfate and potassium sulfate, and bicarbonates such as sodium bicarbonate and potassium bicarbonate . Among them, sodium carbonate, sodium sulfate, and sodium bicarbonate are especially preferred from the standpoint of cost and stability in storage determined by the balance with other components. These compounds may be used individually or in combinations of two or more thereof .

When the (E) component is used, the compounding ratio thereof is preferably set within a range of 5 to 70 wt . % based on the entire present detergent composition. Thus, where the compounding ratio is less than 5 wt . % , the effect of using the washing builder is lost. On the other hand, where the compounding ratio is more than 70 wt.%, the balance of the entire composition is degraded and the synergetic effect with other components, good washing performance, and good stability in storage are typically difficult to obtain. From the standpoint of the effect produced, it is especially preferred that the compounding ratio be set within a range of 30 to 60 wt . % .

Preferred examples of the high-molecular electrolyte polymer that is the (F) component include polymers or copolymers comprising at least one acid from maleic acid and acrylic acid as a monomer and water-soluble alkali salts thereof. Specific examples of suitable polymers include maleic acid polymer, acrylic acid polymer, copolymer of maleic acid and acrylic acid, and water-soluble alkali metal salts thereof. Examples of water-soluble alkali metal salts include sodium salts, potassium salts, ammonium salts, and ethanolamine salts. Among them, sodium salts and potassium salts are preferred. It is especially preferred that sodium salt of polymaleic acid, sodium salt of polyacrylic acid, and sodium salt of a copolymer of acrylic acid and maleic acid be used.

The average molecular weight of maleic acid polymer, acrylic acid polymer, and water-soluble alkali metal salts thereof is preferably 600 to 15,000, more preferably 1,000 to 15,000. Further, the average molecular weight of copolymer of maleic acid and acrylic acid and water-soluble alkali metal salts thereof is preferably 1,000 to 100,000, more preferably 50,000 to 80,000. The water-soluble alkali metal salts of the polymers and copolymers may be completely neutralized salts or partially neutralized salts.

When the (F) component is used, the compounding ratio thereof is preferably set within a range of 0.1 to 6 wt . % based on the entire present detergent composition. Thus, where the compounding ratio is less than 0.1 wt.%, the effect of using the high-molecular electrolyte polymer is lost. On the other hand, where the compounding ratio is above 6 wt.%, the synergetic effect with other components, good washing performance, and good stability in storage are typically difficult to obtain. From the standpoint of the effect produced, it is especially preferred that the compounding ratio be set within a range of 0.5 to 3 wt . % .

Examples of the chlorine-containing bleaching agent, which is the (G) component, include isocyanuric acid salts such as sodium dichloroisocyanurate and trichloroisocyanurate . Among them, the compounds with an effective chlorine content ratio of 55 to 60 wt . % are widely marketed, and from the standpoint of cost, such compounds are preferred.

Where the chlorine-containing bleaching agent, which is the (G) compound, is used, the compounding ratio thereof is preferably set within a range of 0.1 to 4 wt . % based on the entire present detergent composition. Thus, where the compounding ratio is less than 0.1 wt.%, the effect of using the chlorine-containing bleaching agent is lost. On the other hand, when the compounding ratio exceeds 4 wt.%, the balance of the entire composition is degraded, further, the synergetic effect with other components and the desired bleaching and sterilization effect reach saturation. Furthermore, there is a risk that some food vessels that are the articles to be washed will be damaged during processing. From the standpoint of cost, it is especially preferred that the compounding ratio of the chlorine-containing bleaching agent be 1 to 3 wt.%.

No specific limitation is placed on talc, which is the (H) component, and any commercial product can be used. Among these products, those with an average particle size of 1 to 20 μm are preferably used because of an action preventing tablets from damage during tablet production. Where talc, which is the (H) component, is compounded, the compounding ratio thereof is preferably set within a range of 0.1 to 5 wt . % based on the entire tablet detergent composition. Where the compounding ratio is less than 0.1 wt. %, the effect of using the talc is lost. On the other hand, where the compounding ratio is more than 5 wt.%, there is a risk of the strength of the molded tablet decreasing significantly. From the standpoint of cost, it is especially preferred that the compounding ratio be set within a range of 1 to 3 wt.%.

Further, the present detergent composition can also use a solvent, a dye, a perfume, a metal corrosion inhibitor, a bactericidal agent, a deodorizer, an antistatic agent, and an antifoaming agent as additional components .

The present detergent composition is obtained by using the essential components (A) to (D) and, if necessary, optional components (E) to (H) . No specific limitation is placed on the method for manufacturing the present detergent composition and it can be manufactured, for example, by mixing the aforementioned components by using a powder mixing machine such as a Nauta mixer® or a ribbon mixer and then producing tablets in a tableting machine, or by granulating all the components or some of them with a granulator and then producing tablets in a tableting machine.

An extrusion granulator, a flow granulator, a rotary granulator, or a stirring rotary granulator can be advantageously used as the aforementioned granulator. A Spiral Flow (manufactured by Freund Industrial Co., Ltd.) and MuIti -Processor (manufactured by Powrex Co., Ltd.) are examples of flow granulators. Malmerizer (manufactured by Fuji Powdal Co., Ltd.) and CF Granulator (manufactured by Freund Industrial Co., Ltd.) are examples of rotary granulators. Henschel Mixer (manufactured by Mitsui -Miike Engineering Co., Ltd.), High-speed Mixer (manufactured by Fukae Industries Co., Ltd.}, and Vertical Granulator (manufactured by Powrex Co., Ltd.) are examples of stirring rotary granulators.

An apparatus basically comprising a mortar, pestles, and a compression device can be used as the aforementioned tableting machine. Where a pressure is applied between an upper pestle and a lower pestle in a mortar via a compression device, a tablet of a shape determined by the mortar and the pestles can be formed. A generally well-known single-punch tableting machine that produces tablets one by one and a rotary tableting machine of high production efficiency in which a plurality of molds are provided along a rotary round table can be used as the aforementioned tableting machine. Examples of single-punch tableting machines include a vertical powder molding machine and a tough press series manufactured by Kukusui Seisakusho, Ltd. , a P series and PT series manufactured by FETTE Co., Ltd., and a PH series and TRP series manufactured y KORSCH Co., Ltd. A method for supplying a detergent into the automatic washing machine in accordance with the present invention involves accommodating the above-described present detergent composition in a casing of a specific apparatus for supplying a detergent that is set so as to be disposed inside the automatic washing machine. More specifically, the apparatus for supplying a detergent is disposed inside the automatic washing machine, the present detergent composition is gradually dissolved by the washing water and rinsing water sprayed inside the automatic washing machine, and the dissolved high-concentration detergent solution is caused to flow into a washing tank of the automatic washing machine to prepare washing water of a desired concentration that is supplied for washing the article to be washed. The expression "high-concentration" as used hereinabove may be "high concentration" that is high to a degree necessary to prepare the washing water of a desired concentration by supplying the detergent solution into the washing tank and diluting it inside the washing tank.

An apparatus for supplying a detergent comprising a casing that accommodates the tablet-shaped present detergent composition and an open section for bringing the washing water or rinsing water sprayed inside the automatic washing machine into contact with the tablet-shaped detergent composition located inside the casing and also allowing the dissolved detergent to flow out can be used as the aforementioned apparatus for supplying a detergent.

An example of the apparatus for supplying a detergent is shown in Fig. 1. In this example, an apparatus 16 for supplying a detergent is disposed in an undercounter-type automatic dishwashing machine. The automatic dishwashing machine comprises a main body 1 and a boiler 2 for supplying rinsing water into the main body 1. In the upper stage inside the main body 1, dishes 6 that have to be washed are placed on a rack 7.

A pair of washing nozzles 5, 5 and a pair of rinsing nozzles 4, 4 are provided on both sides (above and below) the rack 7, and the rinsing water is supplied to the rinsing nozzles 4, 4 via a hot water pipe 11 extending from the boiler 2. A booster 3 and a rinsing pump 13 are provided in the intermediate zone on the hot water pipe 11.

A washing tank 8 in which an open section at the top surface is covered with a mesh-like strainer pan 9 is provided in the lower stage inside the main body 1. The washing water prepared inside the washing tank 8 is supplied to the washing nozzles S₁ 5 via a washing pipe 12 equipped with a washing pump 14. The reference numeral 15 stands for an overflow pipe for preventing the washing water located inside the washing tank 8 from rising above a certain height.

The apparatus 16 for supplying a detergent is disposed in one corner below the rack 7 carrying the dishes 6 inside the main body 1, as shown in Fig. 2 that is a sectional view along A-A¹ in Fig. 1. The position of the apparatus for supplying a detergent is set so as to be above a waterline 10 of the washing water inside the washing tank 8 and in the channel by which the washing water and rinsing water sprayed from the washing nozzles 5, 5 and rinsing nozzles 4, 4 flow down inside the washing tank 8.

The apparatus 16 for supplying a detergent, as shown in Fig, 3, is composed of an open-end cylindrical casing 21 and a lid body 22 that closes the open section in the top surface of the casing 21. The apparatus for supplying a detergent can be used upon loading the present detergent composition 20 into the casing 21.

Transverse open sections 23 are provided in two positions on a diagonal line in the lowermost portion of the side wall of the casing 21, and when the washing water and rinsing water sprayed from the washing nozzles S₁ 5 (see Fig. 1 and Fig. 2) and rinsing nozzles 4, 4 flow down to the washing tank 8, the water penetrates into the casing 21 through the open sections 23, comes into contact with the present detergent composition 20 located inside the casing and gradually dissolves the present detergent composition, thereby producing a detergent solution. The produced detergent solution exits to the outside of the casing from the same open sections 23 and flows into the washing tank 8.

Because the automatic washing machine performs washing according to a preset washing cycle by identical operations in each cycle, the total quantity of the circulation sprayed washing water and rinsing water is constant in each cycle, and the quantity of the washing water and rinsing water that flows in and out of the open sections 23 of the apparatus 16 for supplying a detergent and comes into contact with the present detergent composition 20 is also constant. Therefore, as long as a sufficient quantity of the detergent composition 20 is present inside the casing 21, the quantity of the detergent that is dissolved and supplied into the washing tank 8 can be maintained at a constant level. Based on this principle, a constant quantity of the present detergent composition 20 is automatically supplied by the apparatus 16 for supplying a detergent, and the automatic dishwashing is completed.

Explaining the washing operation in the automatic washing machine (see Fig. 1) in greater detail, first, dishes 6 are loaded onto the rack 7 and placed on the upper stage of the automatic washing machine. Then, once the switch of washing start is turned on, the washing pump 14 is driven and washing water from the washing tank 8 (washing water of a constant concentration is stored upon completion of the previous washing cycle) is supplied to the washing nozzles 5, 5 via the washing pipe 12.

The washing water is sprayed from the washing nozzles 5, 5 toward the dishes 6 on the rack 7, and the contamination that adhered to the dishes 6 is washed off. The contamination that falls down from the dishes 6 is received by a strainer pan 9, and only the washing water Is returned to the washing tank 8, circulated, and sprayed. At this time, part of the washing water enters the inside of the apparatus 16 for supplying a detergent from the open section 23, dissolves the present detergent composition 20 accommodated inside the casing 21, and produces a high-concentration detergent solution. This detergent solution flows out from the open section 23, flows into the washing tank 8, and is mixed with the washing water located in the washing tank 8 to produce homogeneous washing water.

Once washing ends and a predetermined time elapses thereafter, the rinsing pump 13 is driven and warm water from the boiler 2 is supplied to the booster 3 via the hot water supply pipe 11 to serve as rinsing water heated to 70 to 80⁰C and reaches the rinsing nozzles 4, 4 via the rinsing pipe 17. The rinsing water that is sprayed from the rinsing nozzles 4, 4 rinses the dishes 6, then passes through the strainer pan 9, and flows into the washing tank 8. This rinsing water is mixed with the washing water and is discharged to the outside from the overflow pipe 15. At this time, too, part of the rinsing water enters the inside of the apparatus 16 for supplying a detergent from the open section 23, dissolves the present detergent composition 20 accommodated inside the casing 21, and produces a detergent solution. The rinsing water containing the washing solution flows out through the open section 23 and flows into the washing tank 8 where it is mixed with the washing water located in the washing tank 8, thereby producing homogeneous washing water.

As the operation of the automatic dishwashing machine for repeatedly washing the dishes by the above-described series of steps is being conducted, the present detergent composition 20 located in the casing 21 is gradually dissolved from below, and the upper level of the present detergent composition 20 is lowered by an amount corresponding to the amount of the present detergent composition 20 of the lower part dissolved and consumed, and the portion facing the open section 23 is successively dissolved. By such a process, the present detergent composition 20 of the uppermost portion is moved down to a position facing the open section 23 and dissolved. Therefore, the detergent solution can be supplied into the washing tank 8 until the entire present detergent composition 20 located in the casing 21 is dissolved. Accordingly it is not necessary to replenish the present detergent composition 20 frequently. Moreover, a dissolved high-concentration detergent composition can be supplied into the washing tank 8 with good stability. Furthermore, because the concentration of the washing water prepared in the washing tank 8 can be maintained at a constant level, stable dish finishing can be attained .

Even when the operation conditions in the automatic dishwashing machine are changed, if the quantity of the washing water and the quantity of the rinsing water used for the articles to be washed increases or decreases, the dissolved quantity of the present detergent composition 20 also increases or decreases. The resultant advantage is that the detergent solution of constant concentration can be supplied at all times, without controlling the supplied quantity of the detergent.

It is not necessary for the apparatus 16 for supplying a detergent to have an open-end cylindrical shape as in the above-described examples, and the device can be of any appropriate shape such as a triangular tubular shape or quadrangular tubular shape. However, from the standpoint of easiness of loading the present detergent composition 20 and dissolving the composition inside the casing 21, it is preferred that the apparatus for supplying a detergent have a cylindrical shape as in the above-described example.

No specific limitation is placed on the disposition and shape of the open sections 23 provided in the casing 21, provided that the present detergent composition 20 accommodated inside the casing 21 can come into contact with the washing water or rinsing water sprayed inside the automatic dishwashing machine and that the detergent solution obtained as a result of this contact can flow out. The number of open sections 23 can be appropriately determined according to the type of the automatic dishwashing machine or the washing conditions. Further, the open sections 23 may be formed only in the lower section of the side surface of the casing 21, or they may extend from the lower section of the side surface to the bottom surface. Alternatively the open sections may be formed only in the bottom surface. However, it is preferred that at least one of the open sections 23 be in contact with the bottom surface.

Furthermore, the dissolution rate of the present detergent composition 20 inside the casing 21 differs depending on the type of the washing machine to which the apparatus 16 for supplying a detergent is attached and settings such as the temperature of the washing water and rinsing water. Therefore, it is especially preferred that the dissolved quantity of the detergent could be regulated by adjusting the quantity of washing water and rinsing water that flow into the open section 23. Any mechanism can be used for adjusting the opening degree. For example, a mechanism having a structure shown in Fig. 4A or Fig. 4B can be used.

Thus, in the mechanism shown in Fig. 4A, a casing 21 ^l is in the form of a bottomless cylinder, notches 31 serving as open sections of the same size and the open section 23 shown in Fig. 3 are formed in two locations at the lower edge of the casing, and a receptacle 32 in the form of a cylinder having a bottom section is provided so as to receive the lower section of the casing. The mutual arrangement of the receptacle 32 and the casing 21' can be adjusted in the circumferential direction. On the side wall of the receptacle 32, open guides 33 in the form of open sections that are larger in size than the open sections of the notches 31 are provided in two positions on both sides of the notches 31 of the casing 21' . With such a configuration, by rotating the casing 21' and the receptacle 32 relative to each other in the circumferential direction, arranging the open guide 33 of the receptacle 32 on the notch 31 of the casing 21', and thereby adjusting the size of the open section 23 ' that is produced by the casing and the receptacle, it is possible to adjust the quantity of washing water or rinsing water flowing into or from this portion and to adjust the dissolved quantity of the present detergent composition 20. Therefore, even when the type of the washing machine or the set conditions such as the temperature of washing water and rinsing water are changed, the concentration of the washing water inside the washing tank 8 (see Fig. 1) can be maintained at an optimum level at all times.

Further, in the configuration shown in Fig. 4B, an open section 23" provided in the lower part of the casing 21" is formed to be large in the vertical direction, a guide pipe 34 is provided at the outer circumference of the casing 21", and the position of the guide pipe 34 in the vertical direction with respect to the casing 21" can be adjusted. With such configuration, because the size of the open section 23" of the casing 21" is restricted according to the position of the guide pipe 34 in the vertical direction, it is possible to adjust the quantity of washing water or rinsing water flowing into or from this portion and to adjust the dissolved quantity of the present detergent composition 20. Therefore, even when the type of the washing machine or the set conditions such as the temperature of washing water and rinsing water are changed, the concentration of the washing water inside the washing tank 8 can be maintained at an optimum level at all times.

In the apparatus 16 for supplying a detergent (see Fig. 3} , the engagement method for the casing 21 and the lid body 22 that cover the open section in the upper surface thereof may be in any form, provided that washing water or rinsing water does not enter the casing from the engagement section. In addition to the fitting system such as described in the examples above, a screwing system using a thread or a system of a ladle lid can be used.

From the standpoint of endurance, chemical stability, moldability, and handleability, it is preferred that resin materials such as poly (vinyl chloride), acrylic resins, polyethylene, polypropylene, polycarbonates, ABS, and epoxy resins, or stainless steel such as SUS304, SUS316, SUS410, and SUS430 be used as the constituent materials of the casing 21 (also includes 21', 21" hereinbelow) , lid body 22, receptacle 32, and guide type 34 (see Figs. 3 and 4) .

Where the present detergent composition 20 located inside the apparatus 16 for supplying a detergent is consumed by the operation of the automatic dishwashing machine, the washing solution cannot be supplied to the washing tank 8 and the concentration of the washing water inside the washing tank 8 decreases, causing ineffective washing. Therefore, it is preferred that the casing 21 be made from a transparent material so that the remaining quantity of the present detergent composition 20 inside the casing 21 could be checked visually. Another advantageous approach involves coloring the inner side of the bottom surface of the casing 21 and/or inner surface of the receptacle 32 in a bright color different from that of the present detergent composition (usually of white color) 20, thereby making it possible to confirm easily from the outside that the entire present detergent composition 20 has been consumed.

The weight of the present detergent composition 20 accommodated inside the casing 21 of the apparatus 16 for supplying a detergent is preferably adjusted within a range of from 0.01 kg to 1 kg. Where the apparatus for supplying a detergent with a weight of the detergent composition of less than 0.01 kg is used in automatic dishwashing machines for commercial applications, in the case of a comparatively small undercounter-type machine (for example, with a washing tank capacity of 16 L, a quantity of rinsing water of 4 L/cycle, and a washing solution concentration of 0.1%), because the estimated average number of operation cycles per day is about 50 and the necessary amount of detergent corresponding to such operation is 150 g, the detergent in the apparatus 16 for supplying a detergent has to be frequently replenished and the operation can be troublesome. Where the weight is more than 1 kg, the surface area of the detergent increases. As a result, the surface area of the detergent that comes into contact with the washing water or rinsing water changes significantly depending on the reaming amount of the present detergent composition 20. This is inappropriate because the dissolution rate of the present detergent composition 20 is difficult to control .

Where the apparatus 16 for supplying a detergent is used, the specific gravity of the present detergent composition 20 is preferably within a range of 1.0 to 2.5. Thus, where a detergent composition has a specific gravity less than 1.0, the detergent composition in the apparatus 16 for supplying a detergent has to be frequently replenished and the operation can be troublesome. On the other hand, where the specific gravity is more than 2.5, the dissolution rate decreases and the control of solubility that is the object of the present invention sometimes cannot be attained.

No limitation is placed on the kind or type of the automatic dishwashing machine that is the object of supplying a detergent by using the present detergent composition 20 and the apparatus 16 for supplying a detergent. The examples of suitable automatic dishwashing machines include those of an undercounter type, a door type, a flight conveyor type, a flat conveyor type, and a rack conveyor type. Among them, the present invention can be advantageously used in undercounter- type and door-type automatic dishwashing machines. It goes without saying that the present invention can be applied not only to automatic dishwashing machines, but to a wide variety of automatic washing machines designed for washing various objects such as trays and baskets for conveying and also bottles and cans in supply processing plants. Embodiments

Embodiments of the present invention and comparative examples will be described below in greater detail, However, the present invention is not limited to the below-described embodiments . Embodiments 1 to 56, Comparative Examples 1 to 21

Starting materials for compounding that are shown in Tables 1 to 13 below {units of numerical values in the tables are %) were compression molded to obtain tablet detergents for an automatic dishwashing machine of Embodiments 1 to 56 and Comparative Examples 1 to 21. These tablet detergent compositions were evaluated in respect to eight items: stability in storage, dissolution ability, compressive strength, washing ability, low foaming ability, finishing ability after washing, effect on glass, and scale occurrence inhibition ability. The results are also shown in Tables 1 to 13 below. A method for manufacturing the tablet detergent composition for an automatic dishwashing machine, testing methods for each evaluation item, and evaluation criteria are described below. Manufacturing Method Starting material mixtures prior to compression molding were prepared by mixing starting materials by using a V-type mixer (DVI-I type, manufactured by Dalton Co . , Ltd.) to obtain a charge weight of 3 kg. Each mixing was performed for a mixing time of 10 min at a revolution speed of 30 rpm. A total of 150 g of the mixture prior to molding was placed into a tableting die with a diameter of 52 mm, and compression molding to a tablet shape was performed using a single-punch tableting machine {N60Ξ, manufactured by Okada Seiko KK) by applying a pressure of 117.6 X 10⁴ Pa (12 kgf/cm²) . [Stability in Storage] Test method

One tablet (150 g) of the prepared detergent composition was introduced into a polyethylene bottle with a capacity of 500 mL, placed into a thermo-hygrostat (IG-47M, manufactured by Yamato Kagaku KK) under an atmosphere at a temperature of 40⁰C and a humidity of 70%, and stored for 1 month under such conditions. The appearance thereof was visually observed and evaluated according to the following evaluation criteria. Evaluation criteria

O: No discoloration or deliquescence was observed after 1 month . x: Discoloration and deliquescence were observed after 1 month {significant dissolution of effective chlorine in chlorine bleaching agent compounded product) . [Dissolution ability]

One tablet of the prepared detergent composition was placed on a strainer pan of a commercial automatic dishwashing machine (JWA-400TUD, manufactured by Hoshizaki Denki KK) , and the machine was operated under the following operation conditions. The number of operation cycles of the washing machine required to dissolve completely the tablet detergent composition on the strainer pan was measured and evaluated according to the following evaluation criteria. Operation conditions Washing temperature: 6O⁰C. Washing time: 30 sec. Rinsing process : none . Evaluation criteria

0: Complete dissolution in more than 40 operation cycles. Δ: Complete dissolution in 30 to 40 operation cycles, x: Complete dissolution in less than 30 operation cycles. [Compressive strength]

Compressive strength in the radial direction of the prepared tablet detergent composition was measured according to JIS Z 8841-1993 (Methods for Measuring Strength of Granulated Materials: 3.1. Methods for Compressive Strength Testing) and evaluated according to the following evaluation criteria . Evaluation criteria O: Fracture strength exceeds 40 N.

Δ: Fracture strength is 20 N or more to 40 N or less. x: Fracture strength is less than 20 N.

[Washing ability] Test Method

The prepared tablet detergent composition was loaded in a commercial automatic detergent machine (DW-DR61, manufactured by Sanyo Electric Co., Ltd.) to obtain a detergent solution concentration of 0.1 wt . % and completely dissolved. The machine was then operated under the following operation conditions. A set of 10 ceramic plates serving as the below- described object of washing was washed, and washing performance was evaluated according to the following evaluation criteria. Beef tallow contaminant, contaminant of processed nonglutinous rice powder, and curry contaminant were prepared as test contaminants, and washing evaluation was performed with respect to these contaminants. Operation conditions Detergent concentration : 0.1 wt . % . Washing temperature: 60⁰C. Rinsing temperature: 80%.

Washing course: standard washing cycle (washing: 45 sec, rinsing: 15 sec) .

Hardness of tap water: 80 mg/L (as CaCO₃) . Beef tallow contaminant: refined beef tallow was used. Contaminant of processed nonglutinous rice powder: 75 parts by weight of water was added to 25 parts by weight of processed nonglutinous rice powder, the composition was boiled for 20 min under stirring, and the obtained paste-like product was used.

Curry contaminant: commercial retort curry (trade name: Bon Curry, manufacture by Otsuka Food Co., Ltd.) was used. Articles to be washed: the above-described standard contaminants were caused to adhere at 4 g/plate to ceramic plates with a diameter of 10 cm and dried for 1 h at normal temperature . Evaluation criteria

®: contaminant removal ratio is 90% or more.

O: contaminant removal ratio is 70% or more to less than 90%. Δ: contaminant removal ratio is 50% or more to less than 70%. x: contaminant removal ratio is less than 50%. [Low foaming ability] Test method

The prepared tablet detergent composition was loaded in a commercial automatic detergent machine {DW-DR61, manufactured by Sanyo Electric Co., Ltd.) to obtain a detergent solution concentration of 0.1 wt . % and completely dissolved. Then 30 g of a thoroughly kneaded hen egg (whole egg) was loaded and the machine was operated under the following operation conditions. Foaming of the washing liquid was visually evaluated according to the following evaluation criteria.

Operation conditions

Detergent concentration: 0.1 wt . % .

Washing temperature: 60⁰C.

Rinsing temperature: 80%.

Washing course: standard washing cycle (washing: 45 sec, rinsing: 15 sec) .

Hardness of tap water: 80 mg/L (as CaCO₃) .

Evaluation criteria

®: during operation, foam is at a height of less than 50 mm above the liquid surface; after completion of operation, the foam rapidly disappears.

O: during operation, foam is at a height of less than 50 mm above the liquid surface; after completion of operation, the foam disappears within 1 min.

Δ: during operation, foam is at a height of 50 mm or more above the liquid surface; after completion of operation, the foam disappears within 1 min. x: regardless of foam height during operation, the foam does not disappear and remains even 1 min after completion of operation. xx: immediately after the operation is started, a pump is filled with foam and operation is difficult. [Finishing ability after washing] Test Method The prepared tablet detergent composition was loaded in a commercial automatic detergent machine (DW-DR61, manufactured by Sanyo Electric Co., Ltd.) to obtain a detergent solution concentration of 0.1 wt . % and completely dissolved. The machine was then operation under the following conditions. A set of 10 glass cups serving as the below-described articles to be washed were washed and washing performance was evaluated according to the following evaluation criteria. Operation conditions Detergent concentration: 0.1 wt . % . Washing temperature: 60⁰C. Rinsing temperature: 80%.

Washing course: standard washing cycle (washing: 43 sec, rinsing: 15 sec) .

Hardness of tap water: 80 mg/L (as CaCO₃) .

Object of washing: cow milk was poured into glass cups with a capacity of 200 mL (manufactured by Sasaki Glass Co., Ltd.) and allowed to stay for 5 min. The milk was then discarded and the cups were dried in air for 30 min without rinsing. Evaluation criteria

®: no water spots were observed.

O: 1 to 2 water spots were observed.

Δ: 3 to 5 water spots were observed. x: 6 or more water spots were observed.

[Effect on Glass] Test method

A commercial tumbler glass with a capacity of 200 mL (manufactured by HOYA Co., Ltd.) was immersed under the following conditions into a detergent solution using the prepared tablet detergent composition. The state of the tumbler glass after the immersion was visually observed and evaluated according to the following evaluation criteria. Immersion conditions Detergent concentration: 0.1%. Immersion temperature: 60⁰C. Immersion time: 2 weeks. Evaluation criteria

<8>: neither discoloration nor erosion were observed on the tumbler glass surface.

O: tumbler glass surface was slightly discolored. Δ: significant discoloration of tumbler glass surface, x: significant erosion of tumbler glass surface. [Scale Occurrence Inhibition Ability] Test Method

The present detergent composition was diluted to 0.1% with artificial hard water (total hardness: 150 mg/L as CaCO₃) . A total of 50 mL of the solution was poured into a colorimetric tube with a capacity of 100 mL and held therein for 4 h at 60⁰C. The occurrence of scale was visually determined according to the following criteria. Evaluation criteria

®: no scale appeared.

O: practically no scale appeared.

Δ: scale appeared. x: scale adhesion was significant.

Components used in the compositions described in Tables 1 to 13 below and effective pure ingredients thereof (mass%) are described hereinbelow in greater details. Numerical values in the tables represent the state of each components as is. [A component] Metal salt 1 of saturated fatty acid:

Trade name: magnesium stearate (manufactured by Tannan Chemical Industries Co., Ltd., C = 18). Metal salt 2 of saturated fatty acid:

Trade name: calcium stearate (manufactured by Tannan Chemical Industries Co., Ltd., C = 18) . Metal salt 3 of saturated fatty acid:

Trade name: aluminum stearate (manufactured by Tannan Chemical Industries Co., Ltd., C = 18). Metal salt 4 of saturated fatty acid:

Trade name: calcium palmitate, Grade 1 reagent (manufactured by Kanto Chemical Co., Inc, C = 16) . Metal salt 5 of saturated fatty acid:

Trade name: magnesium myristate, (trial product, C = 14) . Metal salt 6 of saturated fatty acid: Trade name: magnesium caproate, {trial product, C = 6) . Metal salt 7 of saturated fatty acid:

Trade name: magnesium caprylate, (trial product, C = 8) . Metal salt 8 of saturated fatty acid:

Trade name: magnesium behenate, (trial product, C = 22) . Metal salt 9 of saturated fatty acid:

Trade name: calcium lignocerate, (trial product, C = 24} . [B component] Silicate 1

Sodium metasilicate pentahydrate .

Trade name: Dry Sodium Metasilicate 5 aq (manufactured by Koei Chemical Co., Ltd.). Silicate 2

Sodium metasilicate pentahydrate.

Trade name: Sodium Metasilicate Pentahydrate (manufactured by Sanbo Chemical Ind. , Ltd.) . Silicate 3

Sodium metasilicate nonahydrate.

Trade name: Metasilicate Nonahydrate (manufactured by Sanbo Chemical Ind., Ltd.) . Silicate 4

Sodium orthosilicate .

Trade name: Powdered Ortho (manufactured by Nippon Chemical Industrial Co., Ltd.). [C component] Aminocarboxylic acid salt 1 Ethylenediaminetetracetic acid, tetrasodium salt

Trade name: Trilon B (BASF Corp.). Aminocarboxylic acid salt 2

Sodium nitrilotriacetate .

Trade name: Trilon A92R (BASF Corp.). [D component] - (a) Nonionic surfactant 1

Polyoxyethylene (P = 15) polyoxypropylene (q = 9) linear alkyl (C = 14, 15} ether.

EO/PO weight ratio = 1.26.

(Trial product) Nonionic surfactant 2

Polyoxyethylene (P = 8) polyoxypropylene (q = 6) linear alkyl (C = 12, 13) ether.

EO/PO weight ratio = 1.01, cloud point = 31°C.

Trade name: Pepol AS-054C (manufactured by Toho Chemical Industry Co., Ltd.) . [D component] - (b) Nonionic surfactant 3

Trimethylolpropane EO, PO adduct represented by Chemical Formula (2) below.

Average molecular weight = 4,500, EO/PO weight ratio = 0.21.

(Trial product) [Formula 2]

[where k, n, p = 5.7 m, x, q = 20.8] Nonionic surfactant 4

Glycerin EO, PO adduct represented by Chemical Formula (3) below.

(Trial product) [Formula 3]

[where k + n + p = 18 m + x + q = 63j [D component] Nonionic surfactant 5

Polyoxyethylene polyoxypropylene block polymer (pluronic block polymer) .

EO/PO weight ratio = 0.67, average molecular weight 3,300.

Trade name: Epan 740 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). Nonionic surfactant 6

Polyoxyethylene polyoxypropylene block polymer (reverse pluronic block polymer) .

EO/PO weight ratio = 0.67, average molecular weight 2,800.

Trade name: Pluronic PRE 1740 (BASF Corp.). [D component] - (c) Nonionic .surfactant 7 Polyoxyethylene (1.3) acetylenic glycol ether. Trade name: Surfynol 420 (manufactured by Nisshin Chemical Industry Co., Ltd.) . Monionic surfactant 8

2,4,7, 9-Tetramethyl-5-decyne-4 , 7-diol .

Trade name: Surfynol 104 (manufactured by Nisshin Chemical Industry Co., Ltd.) . [E component] Washing builder 1

Sodium carbonate .

Trade name: Soda Ash {manufactured by Tosoh Corp.) . Washing builder 2

Anhydrous sodium sulfate.

Trade name: Neutral Anhydrous Glouber's Salt (manufactured by Shikoku Chemical Corp.) . Washing builder 3

Sodium bicarbonate.

Trade name: sodium bicarbonate (manufactured by Asahi Glass Co. , Ltd. ) . [F component] High-molecular electrolyte polymer 1

Sodium polyacrylate, molecular weight 4,500.

Trade name: Acusol 445ND. High-molecular electrolyte polymer 2 (F component)

Acrylic acid - maleic acid copolymer, sodium salt, molecular weight 70,000. Trade name: Acusol 497ND. [G component] Chlorine bleaching agent 1

Dichloroisocyanuric acid, sodium salt (effective chlorine concentration 60%) .

Trade name: Neochlor 6OG {manufactured by Shikoku Chemical Corp . ) . [H component] Talc 1

Average particle size 9.5 μm, bulk density 0.33 g/tnL .

Trade name: Crown Talc PP (Matsumura Sangyo Co., Ltd.) . Talc 2

Average particle size 2.5 μm, bulk density 0.19 g/mL.

Trade name: High Filler #12 {Matsumura Sangyo Co., Ltd.) . [Other] Metal salt 10 of unsaturated fatty acid

Magnesium oleate (trial product, C = 18).

Trade name: Acusol 497ND. [G component] Chlorine bleaching agent 1

Dichloroisocyanuric acid, sodium salt (effective chlorine concentration 60%) .

Trade name: Neochlor 6OG (manufactured by Shikoku Chemical Corp . ) . [H component] Talc 1

Average particle size 9.5 μm, bulk density 0.33 g/mL .

Trade name: Crown Talc PP (Matsumura Sangyo Co., Ltd.) . Talc 2

Average particle size 2.5 μm, bulk density 0.19 g/mL.

Trade name: High Filler #12 (Matsumura Sangyo Co., Ltd.) . [Other] Metal salt 10 of unsaturated fatty acid

Magnesium oleate (trial product, C = 18).

Table 1

Table 2

Table 3

Table 4

Table 5

Table 6

Table 7

Table 8

Table 9

Table 10

Table 11

Table 12

Table 13

The results presented in Tables 1 to 13 show that the embodiment products 1 to 56 demonstrate excellent performance with respect to all evaluation items, although some compositions are somewhat inferior to others in terms of some characteristics. By contrast, the comparative products 1 to 12 , which do not contain at least one essential component or contain all the essential components, but have the content ratio thereof outside the range of the present invention, show poor results with respect to several evaluation items and are difficult to use.

Further, the following three concentration measurement tests of detergent solution were carried out to evaluate concentration stability of detergent solutions supplied to the automatic dishwashing machine. [Test 1]

One tablet of the detergent composition of Embodiment 43 was loaded into the apparatus for supplying a detergent shown in Fig. 3, the automatic dishwashing machine was operated under the below-described conditions, and changes in the washing solution concentration with time were measured. Operation conditions Hot water temperature: 50⁰C.

Washing machine: JW-400 TUD (tank capacity 16 L), manufactured by Hoshizaki Denki KK.

Washing cycle: 1 cycle, washing 90 sec, interval 3 sec, rinsing time 7 sec. The loaded tablet detergent composition dissolved uniformly and gradually from the lowermost portion thereof, and the washing solution concentration inside the washing tank could be maintained at a predetermined concentration level (about 0.05 wt. %} up to a 54-th washing cycle in which the detergent composition was completely consumed. The results are shown in Fig. 5. [Test 2]

One tablet of the detergent composition of Embodiment 38 was loaded into the apparatus for supplying a detergent comprising a casing 21" shown in Fig. 4B, the automatic dishwashing machine was operated under the below-described conditions, and changes in the washing solution concentration with time were measured. Operation conditions

Opening degree of open section 23": completely open. Hot water temperature: 60⁰C.

Washing cycle: 1 cycle, washing 90 sec, interval 3 sec, rinsing time 7 sec.

The loaded tablet detergent composition dissolved uniformly and gradually from the lowermost portion thereof, and the washing solution concentration inside the washing tank could be maintained at a predetermined concentration level (about 0.12 wt. %) up to a 28-th washing cycle in which the detergent composition was completely consumed. The results are shown in Fig. 6. [Test 3]

Further, the opening degree of the open section 23" was set to 1/2. Then, washing was carried out such that other conditions were identical to those of Test 2. The loaded tablet detergent composition dissolved uniformly and gradually from the lowermost portion thereof, and the washing solution concentration inside the washing tank could be maintained at a predetermined concentration level (about 0.09 wt . %) up to a 36-th washing cycle in which the detergent composition was completely consumed. The results are shown in Fig. 7.

The results obtained demonstrate that with the method for supplying a detergent into an automatic washing machine in accordance with the present invention, the detergent solution can be fed with a stable concentration.

Claims

What Ia Claimed Is:

1. A method for supplying a detergent to an automatic washing machine, comprising the steps of: disposing inside the automatic washing machine an apparatus for supplying a detergent comprising a casing accommodating a tablet detergent composition having the following (A) to (D) components as essential components, and an open section for bringing washing water or rinsing water sprayed inside the automatic washing machine into contact with the tablet detergent composition located inside the casing and for causing the diluted detergent to flow out; causing gradual dissolution of the tablet detergent composition located inside the casing by the washing water or rinsing water sprayed inside the automatic washing machine; and causing a detergent solution of a high-concentration that has been thus dissolved to flow into a washing tank of the automatic washing machine, preparing washing water of a desired concentration, and supplying the prepared washing water to wash articles to be washed:

(A) a metal salt of a saturated fatty acid: 0.01 to 3 wt . % ;

(B) a silicate: 10 to 60 wt . % ;

(C) an aminocarboxylic acid salt: 10 to 60 wt.%; and

(D) a nonionic surfactant: 0.1 to 5 wt.%.

2. The method for supplying a detergent to an automatic washing machine according to claim 1, wherein the automatic washing machine is an automatic dishwashing machine.

3. A tablet detergent composition for an automatic washing machine that is used in the method for supplying a detergent to an automatic washing machine according to claim 1 or 2, the composition having the following (A) to (D) components as essential components:

(A) a metal salt of a saturated fatty acid: 0.01 to 3 wt .%;

(B) a silicate: 10 to 60 wt.%;

(C) an aminocarboxylic acid salt: 10 to 60 wt.%; and

(D) a nonionic surfactant: 0.1 to 5 wt.%.

4. The tablet detergent composition for an automatic washing machine according to claim 3, wherein the metal salt of a saturated fatty acid, which is the (A) component, is a metal salt of a fatty acid having 8 to 22 carbon atoms.

5. The tablet detergent composition for an automatic washing machine according to claim 3 or 4 , wherein the silicate, which is the (B) component, is at least one of an alkali metal metasilicate and a metal orthosilicate .

6. The tablet detergent composition for an automatic washing machine according to any one of claims 3 to 5, wherein the aminocarboxylic acid salt, which is the (C) component, is at least one of an ethylene diaminetetraacetate and nitrilotriacetate .

7. The tablet detergent composition for an automatic washing machine according to any one of claims 3 to 6, wherein the nonionic surfactant, which is the (D) component, is a combination of (a) polyoxyethylene - polyoxypropylene alkyl ether and (b) at least one of an ethylene oxide - propylene oxide adduct of trimethylolpropane and an ethylene oxide - propylene oxide adduct of glycerin.

8. The tablet detergent composition for an automatic washing machine according to claim 7, wherein the nonionic surfactant, which is the (D) component, is a combination of at least one of (a) and (b) according to claim 7 and (c) at least one of 2 , 4 , 7 , 9-tetramethyl-5-decyne-4 , 7-diol and polyoxyethylene acetylenic glycol ether, or derivatives or isomers thereof, the (c) being contained at 0.1 to 3 wt . % based on the entire detergent composition.

9. The tablet detergent composition for an automatic washing machine according to any one of claims 3 to 8, wherein a washing builder comprising at least one of a carbonate, a sulfate, and a bicarbonate is contained as an (E) component at 5 to 70 wt . % based on the entire detergent composition together with the (A) to (D) components .

10. The tablet detergent composition for an automatic washing machine according to any one of claims 3 to 9, wherein a high-molecular electrolyte polymer is contained as an (F) component at 0.1 to 6 wt . % based on the entire detergent composition together with the (A) to (D) components.

11. The tablet detergent composition for an automatic washing machine according to any one of claims 3 to 10, wherein a chlorine bleaching agent is contained as a (G) component at 0.1 to 4 wt . % based on the entire detergent composition together with the (A) to (D) components.

12. The tablet detergent composition for an automatic washing machine according to any one of claims 3 to 11, wherein talc is contained as an (H) component at 0.1 to 5 wt . % based on the entire detergent composition together with the (A) to (D) components.

13. A washing method, comprising the steps of: supplying a dissolved detergent to an automatic washing machine by the method for supplying a detergent to an automatic washing machine according to claim 1 or 2 ; preparing washing water of a desired concentration inside a washing tank of the automatic washing machine; and using the prepared washing water for washing articles to be washed.

14. The washing method according to claim 13, wherein the automatic washing machine is an automatic dishwashing machine .