JP2000282097A - Melting type solid detergent composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a detergent composition capable of suppressing the hydrolysis of an anhydrous condensed phosphate, especially sodium tripolyphosphate over a long period even when formulated with an alkali metal hydroxide at a high concentration and a high temperature. SOLUTION: The characteristic of this melting type solid detergent composition is to have >=0.4 mm grain diameter of an anhydrous condensed phosphate in the detergent comprising water, an alkali metal hydroxide and the anhydrous condensed phosphate. An aqueous solution of an alkali containing the alkali metal hydroxide is maintained at 55-80 deg.C and the anhydrous condensed phosphate having >=0.4 mm grain diameter is mixed and dispersed therein while stirring the aqueous solution to produce the melting type solid detergent composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molten solid detergent and a method for producing the same. More specifically, the present invention provides:
For example, a melt-type solid that has a detergency on hard surfaces that is not inferior to conventional automatic dishwashing detergents, and that has low hydrolysis of condensed phosphates contained in high-concentration and high-temperature alkali metal hydroxides. The present invention relates to a cleaning agent and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, liquid or powder detergents have been used as detergents for hard surfaces, especially for automatic dishwashers. However, for example, in the case of a powder detergent,
If necessary, a method of taking out the cleaning agent from the container in which the worker is placed and putting it into the cleaning agent supply device is adopted, which is not only inefficient in work efficiency but also poses a problem such as danger to the human body, and furthermore, the use of powder cleaning agent. There are drawbacks such as that the detergent solution is not always constant due to the difference in the dissolution rate of the components.
In the case of a liquid detergent, the composition does not change over time, but in order to be a liquid, a large amount of water irrelevant to the detergency must be added, and the active ingredient is smaller than a powder detergent. There is a drawback that a sufficient cleaning effect cannot be obtained, and it is not suitable for the current situation where there is a strong demand for higher performance.

As one method for meeting the demand for higher performance, a method has been adopted in which the cleaning efficiency of the cleaning composition is increased by increasing the cleaning power. For example, U.S. Patent No. 3,166,513,
No. 3,535,285, No. 3,579,455, No. 3,700,599 and No.
As described in 3,899,436, alkali metal hydroxides are generally known to remove strong dirt from food and drink, and condensed phosphate, carbonated The main component is one to which a salt or the like is added, and further, a chlorine-containing compound such as chlorinated isocyanuric acid, an antifoaming agent, and the like are added thereto. As described in JP-B-59-4480 and JP-A-2-84500, for example, such a detergent composition is cast and filled in a plastic detergent container as a solid hydrate detergent. A cartridge type has been proposed. The solid detergent comprises about 50 to 75 parts by weight of a 50% to 75% by weight aqueous solution of an alkali metal hydroxide heated to about 55 to 65 ° C. in about 50 to 75 parts by weight of a sequestering agent (eg, sodium tripolyphosphate). This is a method in which 、 40 parts by weight are blended, and the obtained homogeneous solution is cooled and thickened while being mixed, and the thickened solution is poured into a container and solidified.

However, the above-mentioned solid detergent has poor solubility, and there is a risk that the required amount of detergent cannot be completely dissolved in a short period of time in the initial stage of supplying a new detergent, resulting in insufficient concentration. In addition, condensed phosphate, which is expected to have an excellent effect as a sequestering agent, particularly sodium tripolyphosphate, when condensed in a high concentration and high temperature alkali metal hydroxide as described above, the condensed phosphate rapidly It has been recognized that hydrolysis as a result results in a decrease in the performance as a detergent. This tendency is remarkable in a liquid detergent containing 25% by weight or more of an alkali metal hydroxide, and its solution has been awaited.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an anhydrous condensed phosphoric acid which is not adversely affected by the performance of a detergent even when incorporated in a high concentration and high temperature alkali metal hydroxide. It is an object of the present invention to provide a detergent which suppresses hydrolysis of salts, particularly sodium tripolyphosphate.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present invention has found that the use of anhydrous condensed phosphates, particularly sodium tripolyphosphate having a particle size of 0.4 mm or more, enables cleaning. It does not adversely affect the performance of the agent, and can inhibit the hydrolysis of sodium tripolyphosphate even when blended in a high concentration and high temperature alkali metal hydroxide, and also has a viscosity of 450 to 1 for the detergent.
It has also been found that by setting the molecular weight to 000 cps, the localization of sodium tripolyphosphate in a product can be prevented extremely efficiently, and the present invention has been completed. That is, the present invention provides, in the first invention, a detergent containing water, an alkali metal hydroxide and anhydrous condensed phosphate, wherein the particle diameter of the condensed phosphate is 0.4 mm or more. It is intended to provide a molten solid detergent composition characterized by the following. Further, the present invention provides, in the second invention,
Water, an alkaline aqueous solution containing at least an alkali metal hydroxide is maintained at 55 to 80 ° C., and an anhydrous condensed phosphate having a particle size of 0.4 mm or more is mixed with the aqueous solution while stirring the aqueous solution. An object of the present invention is to provide a method for producing a molten solid detergent composition characterized by dispersing an anhydrous condensed phosphate.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Water in the present invention is a solvent for forming a molten solid detergent, and the content thereof is as follows.
10-30% by weight is preferred. If it is less than 10% by weight, the dissolution and dispersibility of the alkali metal hydroxide is poor. If it exceeds 30% by weight, it is difficult to solidify the product, which has an adverse effect.

The alkali metal hydroxide used in the present invention is preferably a solid or granular alkali metal hydroxide such as flakes or the like, and examples thereof include sodium hydroxide and potassium hydroxide. The content of the alkali metal hydroxide is preferably 25 to 50% by weight. If the content is less than 25% by weight, it is difficult to solidify the product, and at the same time, the performance as a detergent is considered to be inferior.
If it exceeds 0% by weight, the viscosity of the product is affected, and the workability deteriorates.

As the anhydrous condensed phosphate of the present invention, those which are linearly and cyclically condensed and have a degree of condensation of 2 or more can be used. Specifically, for example, sodium tripolyphosphate, sodium hexametaphosphate, Sodium pyrophosphate and sodium trimetaphosphate and their potassium salts and the like can be used. Among them, sodium tripolyphosphate is most preferable because of its high water softening action and cleaning action. The condensed phosphate represented by sodium tripolyphosphate is preferably an anhydride. This is because the stability of the hydrated condensed phosphate is much better when comparing the anhydride with the hydrate (eg, hexahydrate of sodium tripolyphosphate), and its crystal It is presumed that water is made susceptible to alkali metal hydroxide.

In the present invention, it is important to use a condensed phosphate having a specific particle size. In addition, the particle size referred to in the present specification is measured by a method described in Examples described later, and is roughly as follows. That is, as an example, it is sieved with a 3.00 mm sieve, the one that remains on the sieve is “3.00 mm On”, the one that has passed through the sieve is “3.00 mm Pass”, and then “3.00 mm On”.
"Pass" is passed through a 2.00 mm (9.2 mesh) sieve, and what remains on the sieve is "2.00 mm On", and what passes through the sieve is "2.00 mm Pass".
Thereafter, 1.00 mm (16 mesh), 0.84 mm
(20 mesh), 0.59 mm (28 mesh),
In the order of 0.42 mm (36 mesh), 0.21 mm (70 mesh), 0.11 mm (145 mesh),
Pass ”is further passed through a fine sieve and“ 0.11
mm Pass ”. In addition, the ratio is weight%. In addition, “Xmm or more” when displaying the diameter means Xm
It refers to m On, but what is passed through a sieve coarser than Xmm and remains on the sieve also includes those combined. Also, "X
The expression “less than mm” means Xmm Pass, and includes those obtained by passing through a sieve finer than Xmm and passing through a sieve.

In the present invention, the particle size of the anhydrous condensed phosphate is 0.4 mm or more because it is contained in a high-concentration and high-temperature alkali metal hydroxide. That is, 0.4 mm
If it is less than, for example, exposure to a high temperature under a high concentration condition such as an aqueous solution of 25% by weight of sodium hydroxide, the hydrolysis reaction proceeds remarkably. In addition, the larger the particle size, that is, the smaller the surface area per unit volume or unit area, the less affected by the alkali metal hydroxide and the less likely hydrolysis occurs. Poor solubility when used in a dishwasher. Therefore, the particle size of the anhydrous condensed phosphate is preferably 2.00 mm or less. 2.0
When it exceeds 0 mm, it is difficult to uniformly disperse in a detergent, and adversely affects the solubility when used in an automatic dishwasher.

As described above, the particle diameter of the sodium tripolyphosphate contained in the high concentration and high temperature alkali metal hydroxide is preferably from 0.4 mm to 2.00 mm. Further, it is more preferably 0.600 to 2.00 mm, particularly preferably 1.00 to 2.00 mm. 0.4 ~
When the thickness is 0.600 mm, although the hydrolysis is suppressed, the viscosity of the slurry may be too high during the production, and the production may be difficult. If it is 1.00 to 2.00 mm, the hydrolysis is suppressed to 80% by weight or more, and the viscosity of the slurry tends to be in an appropriate range.

[0013] As described above, in the molten solid detergent composition of the present invention, sodium tripolyphosphate is blended at the above particle size, so that sodium tripolyphosphate precipitates and localizes in the detergent due to the specific gravity. Sometimes. Thus, in the present invention, as one form of the detergent composition, the viscosity of the intermediate when the anhydrous condensed phosphate is charged is 450 to 1000 cps, more preferably 600, when the detergent is produced.
When it is set to ８850 cps, localization of sodium tripolyphosphate in the product can be prevented extremely efficiently. In order to adjust the viscosity of the cleaning agent to the above, there is a change depending on the coagulant described below, but for example, a polymer thickener excellent in heat resistance and alkali resistance containing 1.5 to 7.5% by weight is contained. Is preferred. If the amount is less than 1.5% by weight, sedimentation and localization of sodium tripolyphosphate cannot be prevented. If the amount exceeds 7.5% by weight, the viscosity of the product becomes extremely high, which adversely affects workability.

Examples of the polymer thickener include polymers of polyacrylic acid and polyitaconic acid or salts thereof,
Copolymers of vinyl methyl ether-maleic anhydride and salts thereof, polypropylene glycol and the like can be mentioned, and preferably, sodium polyacrylate having a molecular weight of 100,000 to 400,000 is preferred.

The coagulant in the present invention is not particularly limited. For example, anhydrous sodium sulfate, anhydrous sodium carbonate and a mixture thereof can be used, and anhydrous sodium sulfate is particularly preferred. The content of anhydrous sodium sulfate is preferably 1.0 to 5.0% by weight, and 1.0% by weight.
If it is less than 5.0% by weight, the solidification of the product is difficult, and if it exceeds 5.0% by weight, the melting point of the product becomes high, adversely affecting the workability, and the performance when blended in a detergent, especially in an automatic dishwasher. Poor solubility.

In the present invention, any other components can be contained in addition to the above components. These components include, for example, surfactants and bleaching agents. The surfactant referred to here is not particularly limited, but a low foaming agent is preferable. For example, polyoxyethylene polyoxypropylene block copolymer, polyoxyethylene polyoxypropylene condensate of ethylenediamine, phosphate ester, polyoxyethylene It can be a polyoxypropylene alkyl ether or the like. The amount is not particularly limited as long as it does not cause excessive foaming,
2.0% by weight is preferred, and more preferably 0.5 to
1.5% by weight. The bleaching agent referred to herein is not particularly limited, but is, for example, a chlorine-based oxidizing agent such as sodium hypochlorite and chlorinated sodium isocyanurate, and an oxygen-based oxidizing agent such as sodium percarbonate and sodium perborate. Can be.

The molten solid detergent composition according to the present invention comprises:
For example, after dissolving a thickener and a coagulant as needed in water, an alkali metal hydroxide is added and mixed, and
Maintain at ° C. At this time, the viscosity at the temperature is 450
~ 1000cps, more preferably 600 ~ 850cp
Assuming that s, localization of sodium tripolyphosphate in the product can be prevented very efficiently. In order to adjust the viscosity at this time, for example, a polymer thickener excellent in heat resistance and alkali resistance is added in an amount of 1.5 to 7.5% by weight.
Can be contained. If it is less than 1.5% by weight, it is difficult to prevent sedimentation and localization of sodium tripolyphosphate,
If the content exceeds 7.5% by weight, the viscosity of the product becomes extremely high, which may adversely affect workability. In this aqueous alkali metal hydroxide solution, a condensed phosphate having a particle size of 0.4 mm or more is stirred until it is uniformly dispersed, and then solidified.

An example of the production method of the present invention is as follows.
After adding and dissolving 1.0 to 5.0% by weight of a coagulant (e.g., anhydrous sodium sulfate) to 0 to 30% by weight, alkali metal hydroxide (e.g., sodium hydroxide) 25 to 5%
Add 0% by weight and mix. At this time, since the aqueous solution rises to around 90 ° C. due to the heat of dissolution of the alkali metal hydroxide, stirring is continued while allowing the aqueous solution to cool to 55 to 80 ° C. while allowing it to cool. Next, the temperature of the aqueous solution is 55 to 8
After the temperature can be maintained at 0 ° C., 15 to 40% by weight of sodium tripolyphosphate having a particle size of 0.4 mm or more is added, and the mixture is stirred until it is uniformly dispersed. As described above, after the above essential components are completely mixed, this mixture is allowed to stand as it is or in a subdivided packaging container and left at room temperature, and solidifies in 1 to 2 hours. Is obtained.

[0019]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. The particle size of the anhydrous condensed phosphate was measured using a sieve shaker 300-M.
Particle size of 3.00 with M type (manufactured by Tsutsui Riken Kikai)
The mixture was sieved in 9 steps from mm to 0.11 mm and adjusted.
That is, a sieve having a size of 3.00 mm, the material remaining on the sieve was “3.00 mm On”, the material having passed through the sieve was further filtered with a sieve of 2.00 mm, and the material remaining on the sieve was rated “2.0 mm”.
0 mm On "and 1.00 mm, 0.84 m
m, 0.59 mm, 0.42 mm, 0.21 mm,.
What was sieved in the order of 11 mm and what was left on the sieve, respectively,
“1.00 mm On”, “0.84 mm On”, “0.
59mmOn "," 0.42mmOn "," 0.21m
mOn "and" 0.11 mmOn ", and those that passed through the sieve were" 0.11 mmPass ". In addition, sodium tripolyphosphate in each detergent was quantified by high performance liquid chromatography, and the change over time in the residual ratio of sodium tripolyphosphate was the pure content of sodium tripolyphosphate of each particle size before blending. The pure content obtained above of sodium tripolyphosphate of each particle size was divided by 100.
The fraction was defined as the residual rate.

(Example 1) To 25 L of water, 1.5 kg of anhydrous sodium sulfate was added as a coagulant to dissolve, and 42.5 kg of sodium hydroxide was added to mix and dissolve. Stirring was continued while cooling the aqueous solution until the temperature of the aqueous solution dropped to 55 to 80 ° C. Then, sodium tripolyphosphate 25 having a particle size of 2.00 mm or more and less than 3.000 was added.
kg and stirred until homogeneously dispersed. 500 g of this mixture was filled into small-sized packaging containers, left at room temperature for 2 hours, and solidified to obtain a molten solid detergent No. 1 of the present invention. The same operation was carried out except that the particle size of sodium tripolyphosphate was changed to that shown in Table 1, to obtain molten solid detergents Nos. 2 to 9 of the present invention. In Table-2,
The results of the residual ratio of sodium tripolyphosphate after mixing sodium tripolyphosphate of each particle size in the solid detergent prepared in Table 1 and stirring at 60 ° C. for 2 hours are shown. As described above, the hydrolysis of sodium tripolyphosphate has the smallest particle diameter of 2.00 mm or more, and the hydrolysis has significantly proceeded when the particle diameter of sodium tripolyphosphate is less than 0.2 mm.

[0021]

[Table 1]

[0022]

[Table 2]

Example 2 In the same manner as in Example 1, sodium tripolyphosphate sieved to each particle size was blended to prepare a solid detergent shown in Table 3. In Table-4, after blending sodium tripolyphosphate of each particle size in the solid detergent prepared in Table-3, at 60 ° C, 70 ° C, 80 ° C for 2 hours, 4 hours, 6 hours
The results of the residual rate of sodium tripolyphosphate after stirring for hours are shown. The measuring method was the same as in Example 1. The particle size of sodium tripolyphosphate is 0.1
In the case of blending 1 mm On, the hydrolysis proceeded remarkably by stirring at 60 ° C. for 2 hours, and also proceeded remarkably for 4 hours. However, 1.00 mm O
n, when 2.00 mm On was used, even when blended in a high concentration and high temperature alkali metal hydroxide, no rapid progress of hydrolysis was observed, and the change with time after 4 hours was 2 hours. Good results were obtained with little difference compared to the later.

[0024]

[Table 3]

[0025]

[Table 4]

Example 3 After 4.5 kg of anhydrous sodium sulfate was added as a coagulant to 17.9 L of water and dissolved, 2.8 kg of a thickener was added and dissolved. Then, 48.3 kg of sodium hydroxide was added and mixed and dissolved. Stirring was continued while cooling the aqueous solution until the temperature of the aqueous solution dropped to 60 ° C.
2, 30 RPM). Then, when the particle size is 2.0
25 kg of sodium tripolyphosphate, which is less than 0 mm 3.000, was added and stirred until it was uniformly dispersed. In addition,
At this time, the state of the molten solid detergent at the time of production was visually observed to determine whether or not the production was possible. The mixture is filled into small-sized packaging containers in 500 g portions, left at room temperature for 2 hours, solidified, and solidified to obtain the molten solid detergent No. 2 of the present invention.
1 was obtained. The presence or absence of sedimentation / localization of sodium tripolyphosphate was visually inspected, and the results are shown in Table 6. The same operation was performed except that the particle size of sodium tripolyphosphate and each component were changed to those shown in Table 5, to obtain molten solid cleaning agents Nos. 17 to 20, 22 to 27 of the present invention. Thus, the viscosity at the time of adding sodium tripolyphosphate is 600
When it is ８850 cps, the detergent can be obtained very satisfactorily without producing conditions or precipitation of condensed phosphoric anhydride. The production was impossible because the viscosity was too high to stir and the dispersion of sodium tripolyphosphate was insufficient.

[0027]

[Table 5]

[0028]

[Table 6]

[0029]

[Table 7]

* 1): State at the time of production ○: Good production possible ×: Not production possible * 2): Dispersibility of STPP ○: Good dispersion ×: No dispersion ○ ': Very slight localization But there is no problem as a product. -: The test was not completed.

[0031]

According to the present invention, it is possible to suppress the hydrolysis of condensed phosphates, particularly sodium tripolyphosphate, for a long period of time, despite being a high concentration and high temperature alkali metal hydroxide, Deterioration of the performance of the cleaning agent can be prevented.

Claims (14)

[Claims] 1. A cleaning agent comprising water, an alkali metal hydroxide and an anhydrous condensed phosphate, wherein the condensed phosphate has a particle size of 0.4 mm or more. -Type solid detergent composition. 2. The content of the alkali metal hydroxide is from 25 to
The molten solid detergent composition according to claim 1, which is 50% by weight. 3. The molten solid detergent composition according to claim 2, further comprising a thickener and / or a coagulant. 4. The molten solid detergent composition according to claim 1, wherein the anhydrous condensed phosphate is a tripolyphosphate. 5. The molten solid detergent composition according to claim 3, wherein the thickener is polyacrylic acid or a salt thereof. 6. The molten solid detergent composition according to claim 3, wherein the coagulant is anhydrous sodium sulfate. 7. (A) 10 to 30% by weight of water, (B) 25 to 50% by weight of an alkali metal hydroxide, (C) 15 to 40% by weight of an anhydrous condensed phosphate having a particle size of 0.4 mm or more. %, (D) thickener 1.5 to 7.5% by weight, (E) coagulant 1.0 to 5.0% by weight (however, (A) + (B)
+ (C) + (D) + (E) = 100). The molten solid detergent composition according to any one of claims 1 to 6, comprising: 8. An anhydrous condensed phosphate having a particle size of 0.4 mm or more while maintaining an aqueous solution containing at least water and an alkali metal hydroxide at 55 to 80 ° C. and stirring the aqueous solution. And dispersing the anhydrous condensed phosphate. A method for producing a molten solid detergent composition, comprising: 9. The method according to claim 8, wherein the aqueous alkali solution comprising at least water and an alkali metal hydroxide further contains a thickener. 10. The method according to claim 8, wherein the aqueous alkali solution containing at least water and an alkali metal hydroxide further contains a thickener and a coagulant. 11. The method according to claim 8, wherein the viscosity of the aqueous alkali solution is maintained at 450 to 1000 cps when the aqueous alkaline solution is maintained at 55 to 80 ° C.
A method for producing a molten solid detergent composition, comprising mixing an aqueous condensed phosphate having a particle size of 0.4 mm or more with stirring the aqueous solution and dispersing the anhydrous condensed phosphate. . 12. The method for producing a solid cleaning composition according to claim 8, wherein the anhydrous condensed phosphate is sodium tripolyphosphate. 13. The method according to claim 9, wherein the thickener is polyacrylic acid or a salt thereof. 14. The method for producing a molten solid detergent composition according to claim 10, wherein the coagulant is anhydrous sodium sulfate.