JPH0118902B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for stably storing chlorinated isocyanuric acid in a closed container. Traditionally, chlorinated isocyanuric acid has been used as a disinfectant,
Known as an active ingredient in disinfectants, bleaches, etc., chlorinated isocyanuric acid alone or as a composition with other auxiliary ingredients has been commercialized in the form of powder, granules, granules, tablets, etc. However, these drugs containing chlorinated isocyanuric acid usually require a considerable period of time for transportation, storage, etc. after being produced in a factory, for example, over a year in some cases, before being used. During storage, chlorinated isocyanuric acid is likely to decompose, resulting in unfavorable situations such as a decrease in the available chlorine content in chlorinated isocyanuric acid and damage to the container due to gas generation. This happens often, and a countermeasure is strongly desired. However, this does not mean that such countermeasures have not been taken before, and various proposals have been made, but none of them are satisfactory. For example, based on the hypothesis that decomposition of chlorinated isocyanuric acid during storage is due to contact with water that seeps into the container through the container wall, a proposal was made to make the container completely isolated from outside air. However, when put into practice, metal containers tend to corrode, and accidents often occur in which holes develop in sealed containers during storage, or containers are deformed or damaged by internal pressure from generated gas. There is a theory that the cause of this is due to water remaining in the product chlorinated isocyanuric acid without being removed.
Regardless of the validity of this theory, it is no exaggeration to say that it is impossible to completely remove residual moisture from the product chlorinated isocyanuric acid in the industrial production of chlorinated isocyanuric acid. . For this reason, there are many other proposals for stabilizing the chlorinated isocyanuric acid product or its composition drug using a stabilizer. For example, there is a proposal to cover the surface of chlorinated isocyanuric acid with paraffin wax or polyvinyl alcohol film.
The effect is not sufficient, and when chlorinated isocyanuric acid is used for pool disinfection, it is undesirable because it supplies oil into the pool water.
Another proposal is to add and mix potash alum to chlorinated isocyanuric acid and then store it, but the effect is not sufficient and in some cases, the chlorinated isocyanuric acid may be mixed during storage. This is not a safe and practical method as it may accelerate decomposition. Another proposal is to add and mix limonene to chlorinated isocyanuric acid and then store it, but the effect is not as satisfactory as above, and on the contrary, the chlorinated isocyanuric acid becomes yellow during storage. This is not a practical method as it may lead to In addition, there have been proposals for stabilization by adding and mixing sodium carbonate, toluenesulfonamide, benzenesulfonamide, etc. to chlorinated isocyanuric acid, but these methods do not have sufficient stabilizing effects as described above. The present invention is a method for preserving chlorinated isocyanuric acid that does not have the disadvantages of the above-mentioned conventional methods. As a result of experimental research by the present inventors, a small amount of boric anhydride or metaboric acid is It was completed by the new discovery of the fact that acids can be stored extremely stably. An object of the present invention is to provide a method for preserving chlorinated isocyanuric acid or a composition containing the same in a closed container for a long period of time by suppressing decomposition and gas generation thereby. Such a method for storing chlorinated isocyanuric acid or a composition containing the same according to the present invention is such that when storing chlorinated isocyanuric acid or a composition containing the same in a closed container, chlorine is not added to the container. 0.03 to 5% by weight based on isocyanuric acid
of boric anhydride or 0.3 to 10% by weight of metaboric acid. The chlorinated isocyanuric acid to be preserved in the present invention includes trichlorinated isocyanuric acid, dichlorinated isocyanuric acid, etc.
Some industrial products contain less than 1% water. In addition, compositions containing chlorinated isocyanuric acid include the above-mentioned chlorinated isocyanuric acid and auxiliary agents depending on the purpose of use, such as boric acid as a molding lubricant, extenders, blowing agents, etc.; dichlorinated isocyanuric acid Examples include sodium salts, potassium salts, and blends with hydrates thereof. These are powdered,
It may be in either granular or tablet form. Examples of the airtight container in the present invention include conventionally used containers, such as metal containers, plastic containers, containers made of a plastic bag and a paper outer box, and the like. Boric anhydride used in the present invention is represented by the chemical formula B ₂ O ₃ , and metaboric acid is represented by the chemical formula HBO ₂ , and these may be in the form of powder, granules, or tablets. Furthermore, it can also be used in the form of granules, fibers, films, sheets, plates, etc. of plastic compositions containing about 16 to 66% by weight of boric anhydride or metaboric acid in thermoplastic plastics. It will be done. The effective amount of boric anhydride for stably preserving chlorinated isocyanuric acid is 0.01% by weight or more, and 20% by weight based on chlorinated isocyanuric acid.
Above this, the stabilizing effect does not increase even though it is used. A preferred practical range is 0.03 to 55% by weight.
In addition, the effective amount of metaboric acid is 0.1% by weight or more,
More than 20% by weight is unnecessary. In practice, 0.3 to 10
% by weight is a preferred range. In the present invention, as an embodiment in which the above-mentioned chlorinated isocyanuric acid or the composition containing the same and the above-mentioned boric anhydride or metaboric acid are made to coexist in a closed container, first, the chlorinated isocyanuric acid or the composition containing the same is allowed to coexist in the closed container. and boric anhydride or metaboric acid may coexist as a homogeneous mixture. The above-mentioned homogeneous mixture can be easily obtained by using a conventional powder or granule mixing device. This homogeneous mixture is in the form of a powder, but depending on the intended use, it may be further stored in the form of granules, granules, or tablets. This homogeneous mixture is extremely stable during storage, and when used for practical consumption after storage, it is suitable for applications where there is no problem even if boric anhydride or metaboric acid is present, such as for sterilizing pool water. Well, it can be supplied into the pool water. Another embodiment of coexistence is a mode in which chlorinated isocyanuric acid or a composition containing the same and boric anhydride or metaboric acid are allowed to coexist so as not to come into contact with each other in a closed container. As a preferable example, a package containing boric anhydride or metaboric acid tablets or powdered or granular boric anhydride or metaboric acid in an air-permeable and non-leakable bag is placed in a sealed container. A method of installing and enclosing granules, films, fibers, sheets, or plates of a composition containing about 16 to 66% boric anhydride or metaboric acid in a thermoplastic plastic in a cavity in a closed container. Further, a bag, container, etc. made from the plastic composition film or sheet described above is filled with chlorinated isocyanuric acid or a composition containing the same, and this package is further stored in an airtight container. Examples include a method to do so. This method of allowing chlorinated isocyanuric acid or a composition containing it to coexist is advantageous when it is undesirable for boric anhydride or meth to accompany the chlorinated isocyanuric acid or a composition containing it. Preferred examples of the thermoplastic plastic include polyolefin resins such as ethylene polymers, copolymers, propylene polymers and copolymers, vinyl chloride polymers and copolymers, and vinyl resins. As described above, the method of the present invention can be easily carried out in either a mixed state or an unmixed state, depending on the purpose of use of chlorinated isocyanuric acid or a composition containing the same, and can produce extremely stable chlorinated isocyanuric acid. It also makes it possible to preserve compositions containing the same, and has extremely high industrial utility. The present invention will be described in more detail below with reference to Reference Examples, Examples, and Comparative Examples, but the technical scope of the present invention is not limited thereto. Before describing the Examples, first, the storage stability test method will be explained. Test method A (method for measuring the amount of decomposition gas generated) A sample is placed in a three-neck glass container with an internal volume of 500 ml, the first port is sealed with a rubber stopper, and the second and third ports are sealed with glass valves. Attach the stopper, close the valve, and store it in a constant temperature room at 35℃ for 10 days. after that,
Connect a dry nitrogen gas pipe to the second port, and connect it to the third port.
Connect the pipe leading to 50ml of 0.5% caustic soda aqueous solution, open both valves immediately after the above storage period ends, introduce dry nitrogen from the second port, and guide the exhaust from the third port to the caustic soda aqueous solution, causing decomposition. It absorbed gas. After aeration, add 0.2 g of potassium iodide to the caustic soda aqueous solution, and titrate with a 1/10N sodium thiosulfate aqueous solution using starch as an indicator under acidic conditions of acetic acid to determine the amount of available chlorine absorbed in the caustic soda aqueous solution. I asked for it. This effective chlorine amount was taken as the total amount of chlorine gas and nitrogen chloride gas generated from trichloroisocyanuric acid. Test method B (Measurement of state changes in sealed containers) A sample was placed in a medium-low pressure polyethylene bag with a film thickness of 0.15 mm, length of 200 mm, and width of 250 mm, sealed by welding, and oil-soluble ink was applied to the bag surface. Then, put the contents in a 3mm thick cardboard outer box and store it for 40 minutes.
The product was stored in a constant temperature and humidity chamber at 80% relative humidity for 40 days, and the stability was determined by observing the expansion of the bag and the fading of the ink. Reference Example 1 After storing 20g of trichloroisocyanuric acid with a moisture content of 0.43% and a particle size of 0.5 to 1.4mm according to Test Method A, the amount of decomposition gas generated was measured.
It was 0.74 mg. Example 1 20 g of the same trichloroisocyanuric acid powder used in Reference Example 1 and boric anhydride powder with a particle size of 0.05 to 0.15 mm were uniformly mixed in the amounts listed in Experiment Nos. 1 to 7 in Table 1, and the The amount of decomposed gas generated after storage was measured according to Test Method A, and the results shown in Table 1 were obtained. Example 2 Instead of boric anhydride in Example 1, particle size
Experiments Nos. 8 to 14 in Table 1 were conducted in the same manner as in Example 1 except that 0.05 to 0.15 mm of metaboric acid was used, and the amount of decomposed gas generated after storage was measured. The results listed in Table 1 were obtained. Obtained.

[Table] Reference Example 2 The amount of decomposition gas generated from trichlorosisocyanuric acid was measured in the same manner as Reference Example 1, except that the storage period in Test Method A was changed to 7 days instead of 10 days, and it was 0.71 mg. Ta. Reference Example 3 The amount of cracked gas generated was measured in the same manner as in Reference Example 2, except that dichloroisocyanuric acid with a water content of 0.23% and a particle size of 0.2 to 0.07 mm was used instead of trichloroisocyanuric acid in Reference Example 2. Tokoro 0.24
It was mg. Example 3 A polyethylene bag with ventilation holes of 20 mm and 40 mm in length and width was filled with the same amount of boric anhydride as used in Example 1 as shown in Experiment Nos. 15 and 16 in Table 2. Reference Example 2 except that it was suspended from the lower part of the first rubber stopper of the device in Test Method A using a polyethylene thread.
When trichloroisocyanuric acid was stored in the same manner as above, the amount of decomposed gas generated was measured, and the results shown in Table 2 were obtained. Example 4 The same procedure as Example 3 was carried out except that the same dichloroisocyanuric acid used in Reference Example 3 was used in the amount shown in Experiment Nos. 17 and 18 in Table 2 instead of trichloroisocyanuric acid. When the amount of decomposed gas generated after storage was measured, the results shown in Table 2 were obtained.

[Table] Reference Example 4 When 200 g of trichloroisocyanuric acid, the same as that used in Reference Example 1, was tested according to Test Method B, the ink mark on the outer surface of the polyethylene bag was significantly decolored. It was difficult to decipher. In addition, the cardboard outer box was also severely embrittled. Example 5 200 g of trichloroisocyanuric acid and boric anhydride, the same as those used in Example 1, were prepared from Experiment No. 19 in Table 3.
22 were mixed uniformly, and the changes in the state of the polyethylene bag and cardboard outer box were measured according to Test Method B, and the results shown in Table 3 were obtained.

[Table] represents changes in.
Example 6 100 parts by weight of medium-low pressure polyethine and 100 parts by weight of boric anhydride were melt-kneaded and then formed into a sheet with a thickness of 0.15 mm, and a bag with a length of 200 mm and a width of 250 mm was prepared using this sheet. This bag was filled with 200 g of trichloroisocyanuric acid, the same as that used in Example 1, and changes in the condition of the storage bag and cardboard box were measured according to Test Method B above, except that the storage period was 20 days. However, the decolorization of the ink was slight, and the embrittlement of the cardboard was also slight. Comparative Examples 1 to 4 Carboxymethyl cellulose (CMC) with moisture content of 2.0% and particle size of 0.04 to 0.07 mm, moisture content of 0.15%, particle size
Isocyanuric acid from 0.05 to 0.10 mm, particle size from 0.07 to
0.15mm anhydrous sodium carbonate, reagent limonene,
After preparing the same benzenesulfonamide and uniformly mixing the amounts listed in Table 4 with 20 g of the same trichloroisocyanuric acid used in Example 1, the following test method When the amount of decomposed gas generated was measured, the results listed in Table 4 were obtained.

[Table] Comparative Examples 5 to 7 Moisture content 0.32 instead of boric anhydride in Example 1
Example 1 except that orthoboric acid with a particle diameter of 0.04 to 0.10 mm was used in the amount listed in Table 5, and the storage period was 7 days.
After preparing and storing a homogeneous mixture of 20 g of trichloroisocyanuric acid and orthoboric acid in the same manner as above, the amount of cracked gas generated was measured, and the results shown in Table 5 were obtained.

[Table] As shown above, it has been found that when a small amount of boric anhydride or metaboric acid is stored together with chlorinated isocyanuric acid in a closed container, chlorinated isocyanuric acid can be stored extremely stably. It will be done.

Claims (1)

[Scope of Claims] 1. When storing chlorinated isocyanuric acid or a composition containing the same in a closed container, 0.03 to 5% by weight of boric anhydride or 0.3% by weight based on the chlorinated isocyanuric acid is stored in the container. A method for preserving chlorinated isocyanuric acid, characterized by coexisting ~10% by weight of metaboric acid. 2. The preservation method according to claim 1, wherein the boric anhydride or metaboric acid is in the form of powder, granules, or tablets. 3. The preservation method according to claim 1, wherein boric anhydride or metaboric acid is allowed to coexist as a mixture with chlorinated isocyanuric acid or a composition containing the same. 4. The preservation method according to claim 1, wherein boric anhydride or metaboric acid is allowed to coexist with chlorinated isocyanuric acid or a composition containing it without contacting it. 5. The preservation method according to claim 1, wherein boric anhydride or metaboric acid is allowed to coexist in the thermoplastic plastic as a plastic composition containing 16 to 66% by weight of boric anhydride or metaboric acid. 6. The preservation method according to claim 5, wherein the plastic composition is in the form of granules, fibers, films, sheets, or plates.