JP2000063894A - Detergent composition for automatic dishwasher - Google Patents

Abstract

(57) [Abstract] [Object] To obtain a detergent composition suitable for an automatic dishwasher, particularly for home or business use. Each of them has high detergency, excellent cleaning effect, and excellent microbial degradability. [Constitution] An alkali salt and a general formula (Wherein M is H, Na, K or an alkanolamine), which comprises glutamate diacetic acid or a salt thereof as an essential component, and has a pH value of 1% by weight aqueous solution of 9 or more. .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detergent composition used in an automatic dishwashing machine, and more particularly to a detergent composition for home or business use, which has a particularly high cleaning power.
Moreover, after washing, water spots on the tableware surface,
It does not leave stains on the film and has an excellent cleaning effect,
The present invention also relates to a detergent composition for an automatic dishwasher, which is also excellent in biodegradability.

[0002]

2. Description of the Related Art Cleaning agents for automatic dishwashers are supplied to household or commercial automatic dishwashers, and sprayed onto the surface of the dishware to be washed which has stains to decompose or solubilize the stains. By doing so, the dishes are washed.

Such a detergent is usually composed of an alkali agent such as an alkali metal hydroxide and a sequestering agent (builder). Of these, the alkaline agent mainly achieves decomposition and solubilization of stains, and the builder removes factors such as calcium and magnesium that deteriorate the cleaning effect to enhance the cleaning property.

[0004] As this type of detergent, conventionally known is one in which sodium hydroxide as an alkaline agent and a phosphate salt as a builder, such as sodium tripolyphosphate, potassium pyrophosphate, etc. are blended. However, the use of phosphate is very difficult due to environmental concerns.

On the other hand, in recent years, small household automatic dishwashers have become widespread. In this case, in particular, there is a demand for a cleaning agent that is highly safe, has excellent cleaning properties, and is also highly environmentally adaptable.

As a cleaning agent used in this kind of household automatic dishwashing machine, an alkali metal hydroxide and a sequestering agent such as polycarboxylic acid salt, aminocarboxylic acid salt and oxycarboxylic acid salt (builder) have hitherto been used. ) And a detergent are known.

Specific examples of the builder include ethylenediamine tetraacetate (EDTA) and nitrilotriacetate (N
TA), polyacrylates, acrylic acid / maleic acid copolymer salts, malates, citrates and the like.

However, the detergent containing such a builder is inferior in detergency because the sequestering ability of the builder is not sufficient, and further the microbial degradability is also poor.

[0009] Further, not only is the dishwasher for business use used in hotels, restaurants, etc. increased in size year by year, but automation has been advanced to save labor and improve efficiency. In such a washing machine, the cleaning agent is concentrated in one place and is supplied into the washing tank with a predetermined stroke.

However, since most conventional cleaning agents are powdery, it is troublesome to manually measure the powdery cleaning agent, dissolve it in water to form an aqueous solution having a predetermined concentration, and then supply it into the cleaning tank in a predetermined stroke. I was forced to do some kind of operation. Therefore, in order to eliminate such troublesome operations and promote systemization and automation of dishwashing, development of a liquid detergent is required.

As a liquid automatic dishwashing detergent, conventionally, a detergent containing an alkali metal hydroxide and a water-soluble builder is known.

As the water-soluble builder, polycarboxylic acid salts, aminocarboxylic acid salts and the like are used. Specifically, ethylenediaminetetraacetate (EDTA), nitrilotriacetate (NTA), polyacrylate, acrylic acid /
Examples thereof include maleic acid copolymer salts.

However, like the above, these liquid detergents are inferior in detergency due to insufficient sequestration ability of the builder by the builder, and are also poor in microbial degradability.

[0014]

Therefore, an object of the present invention is to provide a detergent composition for an automatic dishwasher, which is excellent in safety in use and has high detergency. It is another object of the present invention to provide a detergent composition for an automatic dishwasher, especially for household use, which has an excellent cleaning finish effect and is also excellent in microbial degradability and has improved the above-mentioned drawbacks existing in the known art.

Further, the object of the present invention is to provide an excellent cleaning finish effect, an excellent microbial decomposability, and a liquid state, which is an improvement of the above-mentioned drawbacks in the known art, particularly for commercial dishwasher cleaning. To provide an agent composition.

[0016]

In order to achieve the above object, according to the detergent composition of the present invention, which is particularly suitable for household automatic dishwashers, an alkaline salt and a general formula are used.

[Chemical 2] (In the formula, M is H, Na, K, or an alkanolamine), and glutamic acid diacetic acid or a salt thereof is contained as an essential component.
The H value is 9 or more.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

(I) A detergent composition suitable for an automatic household dishwasher. As described above, this composition contains an alkaline salt and glutamic acid diacetic acid or a salt thereof as essential components, and exhibits a pH value of 9 to 11 in a 1% by weight aqueous solution.

The above-mentioned alkali salt is a component that mainly achieves decomposition and solubilization of stains. Specifically, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, orthosilicic acid, metasilicic acid, Alkali silicates consisting of sodium or potassium salts such as sesquisilicic acid, carbonates such as sodium carbonate, sodium hydrogencarbonate (sodium bicarbonate), potassium carbonate, and ethanolamines such as monoethanolamine and diethanolamine. Is mentioned. Especially in this, sodium hydroxide,
Alternatively, it is preferable to use sodium hydroxide in combination with another alkali salt.

The content (blending amount) of the alkali salt in the total composition is preferably 20 to 70% by weight, more preferably 30.
˜65% by weight. This is less than 20% by weight, especially 10
When the content is less than 10% by weight, the alkaline buffering capacity becomes low, and therefore, the pH of a 1% by weight aqueous solution of the obtained composition is 9-11.
Difficult to maintain in the range of. Further, even if it is used in an amount of 65% by weight or more, particularly 70% by weight or more, the cleaning effect is not significantly improved.

When an alkali hydroxide such as sodium hydroxide or potassium hydroxide is used as the alkali salt, its content is 5% by weight or less in the whole composition in order to ensure safety. It is preferable.

Further, the above-mentioned glutamic acid diacetic acid or a salt thereof (GLDA) is a component (builder) that enhances the detergency by removing factors such as calcium and magnesium that reduce the detergency effect. Has a general formula of, for example, L-glutamic acid diacetate (L-GL
DA), especially L-GLDA sodium salt.

The above-mentioned GLDA is synthesized by a known Strecker reaction or dehydrochlorination condensation of glutamic acid, preferably L-glutamic acid, obtained by fermentation of starch, saccharides and the like, by a known Strecker reaction.

The content (blending amount) of GLDA is 1 to 30% by weight, preferably 2 to 25% by weight, based on the total composition. If it is 1% by weight or less, no sufficient improvement in cleaning property can be expected, and if 30% by weight or more is used, the cleaning effect is not significantly improved.

The detergent composition thus obtained is a weak alkaline solution having a pH value of 9 to 11 in a 1% by weight aqueous solution, has little harm to the human body and is highly safe. It can be said that the detergent is suitable for a dishwasher. From the viewpoint of ease of use, it is preferable that such a household cleaning agent is in a solid state such as powder, granules, tablets, and paste, but it may be liquid. To form a powder, a bulking agent such as sodium sulfate is used as a balance.

(II) A detergent composition suitable for an automatic dishwasher for business use. As described above, this composition is a liquid containing an alkali salt and glutamic acid diacetic acid or a salt thereof as essential components and having a pH value of a 1% by weight aqueous solution of 12 or more.

The alkali salt is a component for decomposing and solubilizing stains as described above, and is specifically the same as the above-listed components, but it is particularly water-soluble and highly alkaline. It is preferable to use an alkali metal oxide salt or a silicic acid alkali salt, and among them, sodium hydroxide is particularly preferable. If the content of alkali silicate salt is high, silicic acid will adhere to the surface of tableware such as glass and pottery to cause fogging, and the gloss of the pottery will decrease. Absent.

The content (blending amount) of the above-mentioned alkali salt is preferably 10 to 25% by weight, more preferably 12 to 20% by weight, based on the total composition. Below 10% by weight,
It is difficult to maintain the pH of a 1% by weight aqueous solution of the resulting composition at 12 or more, and at 25% by weight or more, the stability of the liquid composition is slightly inferior, but this is not a problem in practical use.

Further, the above-mentioned glutamic acid diacetic acid or its salt (GLDA) is a component (builder) which enhances the detergency by removing factors such as calcium and magnesium which deteriorate the detergency effect, as described above. The compound has the general formula shown in Chemical formula 2, specifically, as described above, L-glutamic acid diacetate (L-GLDA), particularly L-GLD.
A sodium salt may be mentioned. Note that this synthesizing method is similar to that described above.

The content (blending amount) of GLDA is 1 to 35% by weight, preferably 2 to 30% by weight, based on the total composition. If it is 1% by weight or less, sufficient detergency cannot be obtained, and if it is 35% by weight or more, it is difficult to prepare a stable liquid composition.

The detergent composition thus obtained has a pH value of a 1% by weight aqueous solution of 12 or more and is strongly alkaline,
Since it is a liquid, the cleaning effect is extremely high, and it is possible to omit troublesome operations such as powder.
It can be said that the cleaning agent is suitable for an automatic dishwasher for business use in hotels, restaurants and the like.

The above-mentioned detergent compositions (I) and (II)
Any of these may further contain gluconic acid or a salt thereof, and the synergistic effect with glutamic acid diacetic acid or a salt thereof (GLDA) can further enhance the cleaning effect. This content is 0.1-4.3 with respect to 1 part by weight of GLDA.
Parts by weight, preferably 0.5 to 4 parts by weight. This is 0.1
If it is less than 10 parts by weight, the synergistic effect of GLDA is not observed, and if it is more than 4.3 parts by weight, it becomes difficult to prepare a stable liquid composition. Here, sodium gluconate is preferred as the salt of gluconic acid.

The above-mentioned detergent compositions (I) and (II) further contain either one or both of a polycarboxylic acid alkali salt and a phosphonic acid alkali salt, so that the stains removed thereby can re-apply to the dish surface. Contamination can be prevented and the finish after dishwashing can be improved, and scale deposition in the dishwashing tank can also be prevented. This content is 0.02% by weight or more in the entire composition. If this content is 0.02% by weight or less, the above effect cannot be obtained.

The polycarboxylic acid alkali salt is not particularly limited, but an alkali metal salt of a copolymer of acrylic acid and maleic acid is preferable in view of solubility in an alkaline aqueous solution and cleaning effect, and a molecular weight of 2, 000-5,
000 is preferable.

The phosphonic acid alkali salt is a compound having a nitrogen atom in the molecule or a compound having a phosphonoalkylcarboxylic acid structure, but the former compound having a nitrogen atom in the molecule is preferable.

Detergent compositions (I) and (I
In addition to the above-mentioned components, all of I) further suppress chlorine foaming agents such as hypochlorite and the like, oxygen bleaching agents such as sodium percarbonate, and foaming of the cleaning liquid in the automatic dishwashing machine. It is also possible to add an optional amount of a surfactant to be eliminated, fats and oils, starch, or an enzyme that decomposes protein.

When the detergent composition (I) of the present invention is used at a concentration of about 0.5 to 2% by weight, the pH value of a 1% by weight aqueous solution is within the range of 9 to 11. It is necessary to adjust the amount of alkali salt so that If the pH value is 9 or less, the detergency is significantly reduced, and
When it is 1 or more, it becomes a hot alkaline aqueous solution, which is not safe in handling during use.

From the above findings, specific preferable composition ratios of the detergent composition (I) of the present invention are as follows, by way of example.

[0039]     GLDANa salt 2-25% by weight     Sodium carbonate 5-30〃     Sodium bicarbonate 16-40〃     Sodium gluconate 0-4〃     Sodium polycarboxylate 0.02〃     Sodium metasilicate 0-10〃     Sodium sulfate residue (balance)

The detergent composition (I) according to the present invention is diluted with water to prepare a 0.5 to 2 wt% detergent aqueous solution, which is adjusted to a liquid temperature of 60 to 80 ° C. for household use. Dishwashing is performed by spraying the dishes from the washing liquid jet nozzle of the automatic dishwasher.

Regarding the detergent composition (II) of the present invention, when it is used at a concentration of about 0.5 to 1% by weight, a 1% by weight aqueous solution is adjusted to have a pH value of 12 or more by adding an alkali salt. It is necessary to adjust the amount. If the pH value is 12 or less, the detergency is significantly reduced.

From the above findings, the cleaning composition of the present invention (I
Specific preferred composition ratios of I) are as follows, as an example.

[0043]     GLDANa salt 2-30% by weight     Sodium hydroxide 12 ~ 20〃     Sodium metasilicate 0-5 〃     Sodium gluconate 0.5-4 〃     Sodium polycarboxylate (Copolymer of acrylic acid and maleic acid.                               Molecular weight 3,000) 0.02% by weight     Water tap water balance (balance)

The detergent composition (II) according to the present invention is diluted with water to prepare a 0.5 to 1% by weight aqueous detergent solution, which is adjusted to a liquid temperature of 50 to 80 ° C. Dishwashing is performed by spraying the dishes from the washing liquid jet nozzle of an automatic dishwasher for business use such as restaurants.

The cleaning composition (II) according to the present invention can be applied to various containers used in the food industry, chemical industry, etc., and further, cleaning tanks, devices, workplaces, etc., tank vehicles and containers. It is also applied to the cleaning of vehicles such as vehicles. In this case, the detergent composition (II) of the present invention
Is diluted to an appropriate concentration according to the purpose to prepare a desired washing solution, and washing is performed by a washing method such as immersion washing, jet washing, brush washing and spray washing.

[0046]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 A 1% by weight aqueous solution of each sample composition shown in Table 1 was used as a test sample, and the pH of each sample was measured.
A detergency test was conducted and the results are shown in Table 1. The water used for dilution is artificial hard water having a calcium carbonate hardness of 80 ppm. The pH was measured by measuring the pH value of each sample at room temperature with a pH meter.

The washability test was carried out on each sample as an automatic dishwasher by National Dishwasher [Matsushita Electric Industrial Co., Ltd.]. Part No. NP-5800M], cleaning temperature 5
It was carried out by washing the following two types of objects to be washed under the conditions of 5 ° C., washing time of 10 minutes, and rinsing time of 2 minutes.

Washed item 1: 3 g of artificial dirt [1: 1: 1 (weight) mixture of beef tallow, egg and flour] was adhered and left at room temperature for 1 day. Five pieces of each sample aqueous solution were prepared.

Washed article 2: 1 at room temperature after soaking in commercial milk
An air-dried glass cup. 1 for each sample solution
I prepared 0 each.

Each of the components shown in Table 1 is a pure content equivalent amount. GLDA-4a is sodium glutamate diacetate, sodium hydroxide, sodium carbonate, sodium gluconate, and sodium sulfate are first-class reagents, and sodium metasilicate is a first-grade reagent of nonahydrate. In addition, sodium polycarboxylate is a product name “Sokaran CP12S” manufactured by BASF (a copolymer of maleic acid and acrylic acid,
As the sodium phosphonate having a molecular weight of 3,000), the product name "Diquest 2006" manufactured by Nippon Monsanto Co., Ltd. was used. The nonionic surfactant has a purpose of defoaming effect, and a polyoxyalkylene ether type nonionic surfactant [Adecanol B-2030 manufactured by Asahi Denka Kogyo Co., Ltd.] was used.

With respect to the effect of the washability, in the case of the article to be washed 1, the surface of the ceramic dish after washing and rinsing was visually observed, evaluated according to the following criteria, and the evaluation result was divided by the number of repetitions to give an average evaluation. I asked.

"A": Dirt is completely removed. Moreover, redeposition of dirt is not seen, and the finishing effect after cleaning is excellent. "○": Dirt is completely removed. However, a slight amount of redeposition of dirt was observed, and although the effect of cleaning and finishing the surface of the pottery dish was not perfect, it was not a problem. "△": Dirt is completely removed. However, a little redeposition of dirt was observed, and although the effect of cleaning and finishing the surface of the pottery dish was not sufficient, it was not a serious problem. “X”: Dirt removal is not complete. Dirt remains on the surface of the ceramic dish after washing.

In the case of the item to be washed 2, the surface of the cup after washing and rinsing was visually observed and evaluated according to the following criteria.
The evaluation result was divided by the number of repetitions to obtain the average evaluation.

"◯": No water spots, streaky stains, stain film, and gloss on the glass surface. “Δ”: Water spots and streaky stains were slightly observed, and the gloss of the glass surface was slightly inferior, but it was not a problem. "X": Many water spots and streaky stains were observed, and the gloss of the glass surface was inferior.

The evaluation test of "solution stability" is as follows. "○": The sample solution is uniform and transparent. “X”: Separation, crystallization, solidification, etc. are observed in the sample solution.

[0057]

[Table 1]

The following can be seen from Table 1. The sample Nos. 1 to 14 of the present invention all have a pH value of 9 to 1
It is within the range of 1 and is excellent in handling safety.

Further, in all of the sample Nos. 1 to 14 of the present invention, the criterion for judging the cleaning property is "⊚" to "Δ", the cleaning power is high and the cleaning finishing effect is also excellent.

On the other hand, the sample No. 1 of the comparative example does not contain an alkali salt, so that the pH value of the 1% aqueous solution is as low as 9 or less and the detergency is poor. Further, the comparative sample No. 2 does not contain GLDA-4Na, and therefore is also inferior in cleanability.

Example 2 A 1% by weight aqueous solution of each sample composition shown in Table 2 was used as a test sample, and the pH value of each sample was measured and the undiluted solution of each sample composition was observed. The results are shown in Table 2. The water used for dilution is artificial hard water having a calcium carbonate hardness of 80 ppm.

The pH value is measured by measuring the pH of each sample at room temperature.
It was performed by measuring the value with a pH meter. In addition, the appearance of the undiluted solution of the composition was observed at room temperature, at a low temperature of -5 ° C,
After being left at a high temperature of ° C for 1 week, the appearance of the sample was visually observed to evaluate the "solution stability" of the sample.

The washability test was carried out on each sample as an automatic dishwasher by National dishwashing dryer [Matsushita Electric Industrial Co., Ltd.]. Part No. NP-5800M], cleaning temperature 8
Under the conditions of 0 ° C., a washing time of 60 seconds, and a rinsing time of 60 seconds, the same items to be washed 1 and 2 as those in Example 1 were obtained.
Was washed. Each of the components in Table 2 is the same as that in Table 1, and is the pure equivalent amount as in Table 1. The evaluation criteria are also the same as in Table 1.

[0064]

[Table 2]

The following can be seen from Table 2. Each of the example samples Nos. 1 to 12 according to the present invention has a pH value of 12 or more and is excellent in cleanability, and all are uniform and transparent, and are excellent in solution stability of the sample.

On the other hand, the comparative sample No. 1 is GLDA-4Na.
Is not included, and the pH value of the 1% aqueous solution is 12 or less, the cleaning property is poor. Moreover, although the pH value of each of the comparative sample Nos. 2 to 4 was maintained at 12 or more, the GLDA-
Since it does not contain 4Na, it is also inferior in detergency. Further, since Comparative Samples Nos. 3 and 4 have a high sodium hydroxide content, separation, crystallization, solidification, etc. are observed in the samples and the solution stability is poor.

[0067]

As described above, since the detergent composition (I) according to the present invention maintains a weak alkali having a pH of 9 to 11, it is excellent in handling safety during use and has high detergency. Furthermore, it has an excellent washing finish effect and an excellent solution stability, and is particularly suitable for use in household automatic dishwashers.

Further, the detergent composition (I
I) Since it maintains a strong alkali having a pH of 12 or more, it has a very high detergency and an excellent cleaning finish effect, and exhibits a liquid state, which is particularly suitable for use in a commercial dishwasher.

Further, in the above-mentioned detergent compositions (I) and (II), since the main components are easily decomposed by microorganisms, the waste liquid is decomposed by microorganisms after the disposal, which also contributes to environmental protection. preferable.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shin Saito             Akira 2-3 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa             Wadenko Co., Ltd.Uchikawasaki Factory (72) Inventor Toru Yamamoto             Akira 2-3 Chidori-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa             Wadenko Co., Ltd.Uchikawasaki Factory F-term (reference) 4H003 AC06 BA09 BA15 BA17 DA19                       EA12 EA15 EA16 EA21 EB08                       EB13 EB14 EB24 EB30 EB32                       FA03 FA21 FA28

Claims (10)

[Claims] 1. An alkali salt and a compound of the general formula: (In the formula, M is H, Na, K, or an alkanolamine), and glutamic acid diacetic acid or a salt thereof is contained as an essential component.
A detergent composition for an automatic dishwasher, which has an H value of 9 or more. 2. The composition according to claim 1, wherein the content of the alkali salt is 20 to 70% by weight in the total composition, and the content of glutamic acid diacetic acid or a salt thereof is 1 to 1 in the total composition.
30% by weight, 1% by weight of the aqueous solution has a pH value of 9 to 11, and the composition is in the form of powder, granules, tablets or pasty solids, mainly for household automatic dishwashing. A cleaning composition for an automatic dishwasher according to claim 1, which is suitable for a machine. 3. The composition according to claim 1, wherein the content of the alkali salt is 10 to 25% by weight in the total composition, and the content of glutamic acid diacetic acid or its salt is 1 to 5 in the total composition.
The automatic dishwashing according to claim 1, which is 35% by weight, the pH value of the 1% by weight aqueous solution is 12 or more, and the composition is in a liquid state, which is mainly suitable for an automatic dishwasher for commercial use. Machine cleaning composition. 4. The method according to claim 1, wherein the alkali salt is one or more selected from the group consisting of alkali metal hydroxide, alkali carbonate, alkali silicate and ethanolamines. A cleaning composition for an automatic dishwasher according to any one of 1. 5. The detergent composition for an automatic dishwasher according to claim 2, wherein when the alkali salt is an alkali hydroxide salt, the content is 5% by weight or less in the entire composition. object. 6. The cleaning composition for an automatic dishwasher according to claim 1, further comprising gluconic acid or a salt thereof. 7. The automatic tableware according to claim 6, wherein the content of gluconic acid or a salt thereof is 0.1 to 4.3 parts by weight with respect to 1 part by weight of glutamic acid diacetic acid or a salt thereof. Detergent composition for washing machine. 8. The cleaning composition for an automatic dishwasher according to claim 1, further comprising an alkali salt of polycarboxylic acid and / or an alkali salt of phosphonic acid. object. 9. The content of the polycarboxylic acid alkali salt and / or the phosphonic acid alkali salt in claim 8 is 0.02 weight percent or more in the entire composition.
The cleaning composition for an automatic dishwasher according to 1. 10. The cleaning composition for an automatic dishwasher according to claim 8, wherein the alkali salt of polycarboxylic acid is an alkali metal salt of a copolymer of acrylic acid and maleic acid.