JP2711983B2 - Disinfection tablets - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tablet for disinfecting and disinfecting formed by mixing trichloroisocyanuric acid (hereinafter referred to as TICA) and granular calcium carbonate, and does not swell or disintegrate when contacted with water. An object of the present invention is to provide a disinfecting tablet which gradually dissolves from its surface and does not lower the pH of treated water.

[0002]

2. Description of the Related Art Solid chemicals that release active chlorine used in a circulating water system such as pool water or a closed water system such as water storage include advanced salad powder and chlorinated isocyanuric acid compounds. Among them, TICA is particularly widely used because it has a high active chlorine content, is completely dissolved when put into water, does not generate insolubles, and has excellent storage stability.

[0003] However, TICA has relatively low solubility at room temperature, and its tablet-compacted one has further poor solubility, so that it is difficult to maintain the expected active chlorine concentration, and sudden contamination of treated water occurs. In such a case, there is a problem that sufficient sterilization cannot be performed. When used in a circulating water system such as a pool or in a closed water system such as a reservoir, hydrochloric acid is generated by the decomposition of active chlorine, which accumulates and lowers the pH of treated water, causing corrosion and deterioration of piping and containers. It was causing trouble.

Some proposals have been made to solve these problems. For example, as a proposal for improving the dissolution rate of a solid drug, Japanese Patent Application Laid-Open No. 5-43407 discloses a method using tablets of dichlorisocyanurate hydrate having high solubility, and Japanese Patent Application Laid-Open No. 51-139628 discloses a method using dichloroisocyanur. JP-A-58-59904 discloses a method of using a tablet comprising TICA, cyanuric acid and an alkali metal salt or an alkaline earth metal oxide, and JP-A-1-128905 discloses a method using a TIC.
A tablet is disclosed which is obtained by mixing A with orthoboric acid and pressing the mixture.

On the other hand, in order to prevent acidification of treated water,
JP-A-59-67208 discloses a tablet containing TICA, isocyanuric acid and a magnesium salt or a calcium salt, and JP-A-1-132504 discloses a tablet prepared by adding sodium dichlorisocyanurate or a hydrate thereof to magnesium oxide, hydroxide. There has been proposed a tablet obtained by mixing and pressing one or more kinds of alkali compounds consisting of magnesium, calcium hydroxide and sodium carbonate.

Further, as a method for preventing a pH decrease in a circulating water system or a closed water system, JP-A-58-2055 has been proposed.
No. 81 proposes a method in which an agent formed by molding one or a mixture of two or more of hydroxides, carbonates and basic carbonates of alkaline earth metals is brought into contact with pool water.

[0007]

Tablets containing dichloroisocyanurate or a hydrate thereof as an active ingredient do not have sufficient storage stability at high temperatures and have a defect that the tablet may be disintegrated or swelled depending on use conditions. Was. When TICA is used in the form of a tablet formed by combining cyanuric acid with an alkali metal salt or orthoboric acid, the content of TICA decreases and a large number of tablets must be used. There was a problem that the compound of No. remained.

[0008] An object of the present invention is to reduce the pH of treated water even when repeatedly used in a circulating water system such as pool water or a closed water system such as water storage, dissolve tablets at an appropriate speed from the surface, and preserve the storage stability. It is intended to provide a composition tablet of TICA which is excellent in the above.

[0009]

Means for Solving the Problems The inventors of the present invention have repeatedly studied in view of such circumstances, and as a result, have obtained 100 parts by weight of TICA.
In contrast, 90% or more is in the range of particle size of 0.2 to 3 mm.
That by pressure-molding a composition containing the calcium carbonated 5-70 parts by weight, found that tablets capable of attaining the intended purpose can be obtained, thus leading to complete the present invention.

[0010] TICA used in the practice of the present invention
May be in the form of powder or granules, but granules are preferred in consideration of handling during tableting. In addition, as the calcium carbonate used in the practice of the present invention, 90% or more of the particles are those having a diameter of 0.2 to 3 mm, and particularly those obtained by pulverizing cold water stone to a particle diameter of 0.5 to 2 mm. Is preferred.

When calcium carbonate having a particle size of less than 0.2 mm is used, the dissolution rate is too high.
The tablet may dissolve earlier and disintegrate in water.
Conversely, when calcium carbonate having a particle diameter of more than 3 mm is used, it is difficult to uniformly mix it with TICA, and calcium carbonate particles remain insoluble in water, which is not preferable. Therefore, calcium carbonate used as a raw material
The particle size is less than 0.2mm or more than 3mm
If more than 10% is contained, the above trouble is remarkable.
Occurs.

When sodium carbonate or calcium hydroxide is used in place of calcium carbonate, these are more easily dissolved than TICA, so that they are easily disintegrated when tablets are put in water, and are stable during storage. It is not suitable for practical use because its properties are reduced.

The mixing ratio of TICA to calcium carbonate in the tablet for sterilization and disinfection of the present invention is such that calcium carbonate is 5 to 70 parts by weight, preferably 10 to 100 parts by weight of TICA.
The range is from 50 to 50 parts by weight. If the mixing ratio of calcium carbonate to TICA is less than 5 parts by weight, the pH of the treated water
The function of preventing the decrease is inferior, and if it exceeds 70 parts by weight, the dissolution rate of the tablet becomes too fast, and the storage stability is undesirably reduced.

In producing the tablet for sterilization and disinfection of the present invention, a commonly used dry blender and tableting machine can be used, and a small amount of stearate is used to improve the lubricity of the tablet. Tablets can be mixed after mixing them.

[0015]

The tablet for disinfection and disinfection of the present invention, when brought into contact with water, gradually dissolves the TICA on the tablet surface to generate active chlorine. This active chlorine finally changes into hydrochloric acid, but this hydrochloric acid reacts with calcium carbonate contained in the tablet and changes into calcium chloride, so that a decrease in pH of the treated water is suppressed. According to the present invention, the size of calcium carbonate is in the range of 0.2 to 3 mm in particle size, and calcium carbonate is blended in a ratio of 5 to 70 parts by weight with respect to 100 parts by weight of TICA. Most react with hydrochloric acid and can completely dissolve all ingredients in the tablet.
The present invention will be specifically described with reference to Examples and Comparative Examples.

[0016]

【Example】

(Examples 1 to 5 and Comparative Examples 1 to 6) Granular TICA1
To 00 parts by weight, calcium carbonate having a particle size as shown in Table 1 and magnesium stearate as a lubricant are uniformly mixed at respective mixing ratios. Using a continuous tableting machine having a mold of 50 mm in diameter,
Press molding under tableting conditions of 00 kg / cm ² and weigh 100
g of columnar tablets were obtained.

The above-mentioned cylindrical tablet is crushed using a mortar,
While measuring the available chlorine content, this pulverized product was put into a container containing 50 liters of tap water having an M-alkalinity of 55 mg / liter and pH 7.4 so that the available chlorine concentration became 135 mg / liter. A solution was prepared. The lid of this container was loosely closed and allowed to stand outdoors for one week, and then ozone gas was blown into the container to decompose the remaining available chlorine, and then the pH of the solution was measured. The amount of the crushed tablet, the effective chlorine content after standing, and the measured pH value of the tablet charged in tap water were as shown in Table 2.

[0018]

[Table 1]

[0019]

[Table 2]

A wire mesh is placed at the center (water depth 10 cm) of a plastic water tank (water depth 27 cm) containing 68 liters of water, and one tablet weighed in advance is placed on the wire mesh and allowed to stand for 2 days. The tablets were taken out, the weight was measured, and the reduction rate was determined from the measured values of the tablet weight before and after this test. The state of the tablets and the bottom of the water tank at the time of removal was visually observed. The results were as shown in Table 3.

[0021]

[Table 3]

[0022]

The tablet for disinfection and disinfection of the present invention dissolves gradually from the surface without disintegration or swelling when put into water, can supply active chlorine for a long time, and has passed for a long time. Since it does not lower the pH of the treated water later, it is extremely useful for disinfection of swimming pool water, septic tank drainage and various wastewater.

Claims (1)

(57) [Claims] Respect 1. A 100 parts by weight of trichloro isocyanuric acid, pressurizing the composition more than 90% was blended 5 to 70 parts by weight carbonated calcium <br/> Ru Ah in the range of particle sizes 0.2~3mm A tablet for sterilization and disinfection characterized by being formed by compression.