JPH0892018A - Oxidizing water for microbicide and its production - Google Patents

Abstract

PURPOSE: To produce an oxidizing water for microbicide capable of effectively protecting a plant from microbial damage and preventing the accumulation of chlorine in soil since it contains essentially no chlorine. CONSTITUTION: This oxidizing water is produced by supplying hydrogencarbonate-containing water into an anode chamber of a water electrolysis apparatus and electrolyzing it. One or plural kinds are selected from among sodium hydrogencarbonate, potassium hydrogencarbonate and ammonium hydrogencarbonate as the hydrogencarbonate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing oxidative water for sterilization for sterilizing microorganisms that cause plant diseases in agriculture, forestry, horticulture and the like, and oxidative water for sterilization obtained by the method.

[0002]

2. Description of the Related Art It is said that there are about 1,000 or more kinds of plant disease fungi, and the reduction of agricultural yield due to them is said to be about 20%. The damage from forestry and gardening has not been estimated, but the amount is greater than expected. In addition, healthy growth of turf is a top priority at golf courses, and the vast area of the golf course is covered with plants, so the amount of work required to protect the plants from pests is extremely large.

A large number of organic synthetic pesticides have been developed as a method for preventing or reducing damages caused by plant pathogenic fungi in agriculture, forestry, horticulture and golf courses, and have great effects on food production and environmental greening. However, synthetic organic pesticides are not universal, and in recent years, the idea of comprehensive pest control has been proposed in which disease control is carried out by combining various methods such as agricultural control methods and biological pesticides.

In order to develop a disease control method other than organic synthetic pesticides, tap water is supplied to the anode chamber of a water electrolysis apparatus in which an anode chamber and a cathode chamber are formed through an ion exchange membrane or a diaphragm to electrolyze. Oxidized water produced by the above has been developed and put into practical use as a fungicide for plants. Oxidized water is generated by simply energizing an anode and a cathode, which are arranged with an ion exchange membrane or a diaphragm interposed in the anode chamber and the cathode chamber, and has a pH of 2.7 or less, a redox potential of 1000 mV or more, and dissolved oxygen. 20 to 30 ppm, available chlorine 30 to 40 pp
It has a general physical property of m.

[0005]

However, in order to achieve this physical property and to improve the stability of the oxidizing water and improve and maintain the sterilizing power, the oxidizing water contains chlorides such as sodium chloride and potassium chloride. Has been added. Potassium is used by plants as one of the three major nutrients, but chlorine is not used and accumulates in soil, causing a problem of salt damage.

[0006] The present invention solves the above problems in oxidizing water for sterilization, can effectively protect plants from the damage of microorganisms, is substantially chlorine-free and accumulates chlorine in soil. It is an object of the present invention to provide a sterilizing oxidized water capable of preventing the above and a method for producing the same.

[0007]

In the method for producing oxidative water for sterilization of the present invention, water containing hydrogen carbonate is supplied to the anode chamber of a water electrolysis apparatus and electrolyzed to produce oxidized water. To do. The structure and material of the electrodes of the electrolyzer for producing oxidized water are not particularly limited. Electrodes generally used for producing alkaline ionized water, deoxygenated water, ozone or ozone water can be used. The basic structure of the electrode is titanium on both the positive and negative electrodes with a cation exchange membrane such as Nafion in between.
Stainless steel, or a platinum-plated material grid, expand, punched plate, perforated plate, etc. are laminated or adhered in multiple layers, and a current collector is attached to one or more laminated plates or multilayer plates, and then plastic, Store in a case made of aluminum or stainless steel. Carbon-based materials can also be used for the electrodes.

The structure and material of the negative and positive electrodes are determined by the desired physical properties of the oxidizing water. At the time of electrolysis, a voltage of 3 V or more is applied between the anode and the cathode which are arranged with the ion exchange membrane or the diaphragm sandwiched in the anode chamber and the cathode chamber of the water electrolysis apparatus formed through the ion exchange membrane or the diaphragm. Energize by applying voltage. By electrolysis, oxidized water having a pH of 2.7 or less and an oxidation-reduction potential (ORP) of 1000 mV or more can be obtained.

At this time, while supplying a small amount of tap water or ion-exchanged water to the cathode chamber, 10 ppm of hydrogen carbonate is fed to the anode chamber.
A suitable oxidizing water can be produced by supplying a solution containing 0 to 2000 ppm and electrolyzing at a voltage between electrodes of 4 to 25V. The water supplied to the cathode chamber is preferably ion-exchanged water in order to prevent the calcium salt and magnesium salt contained in the water from depositing on the surface of the metal material forming the cathode. When tap water is used, the cations in the bicarbonate solution supplied to the anode chamber pass through the cation exchange membrane and move to the cathode side, and due to hydroxide ions generated by electrolysis of tap water, etc. The pH of the cathode water rises remarkably, and calcium or magnesium ions and carbonate ions or hydroxide ions contained in tap water in trace amounts cause their salts to deposit on the surface of the cathode constituent material. The deposited substance raises the internal resistance between the electrodes, which makes long-term continuous operation impossible. Therefore, when tap water is used, it is necessary to periodically wash it with a dilute acetic acid solution or to elute it by polarity conversion in order to remove the substance containing calcium carbonate as a main component deposited on the cathode surface.

As another name for the hydrogen carbonate, there are acid carbonate and bicarbonate. Examples of hydrogen carbonate to be added include sodium hydrogen carbonate, potassium hydrogen carbonate, and ammonium hydrogen carbonate. All of these compounds have been or have been used as pharmaceuticals or food additives. However, potassium hydrogen carbonate, which has been used as an antacid, has not been used at present because of its toxicity.

Sodium hydrogencarbonate is most preferred because of its price, ease of electrolysis, and bactericidal activity. The addition amount is preferably as small as possible from the viewpoint of cost, treatment of cathode water, and avoiding unnecessary accumulation of foreign matter in soil, and 100 to 2000 ppm is preferably added. 30
The range of 0 to 1000 ppm is more preferable. The voltage between electrodes is controlled according to the change in internal resistance between the electrodes due to the deposition of salts on the surface of the cathode.

[0012]

By the electrolysis, oxidized water having a pH of 2.7 or less and an oxidation-reduction potential (ORP) of 1000 mV or more is obtained. This oxidized water contains virtually no sodium or chlorine, and when used for sterilization of plant pathogens in agriculture, forestry, horticulture, and golf courses, it accumulates chlorine, sulfate, or nitrate in the soil. Without this, for example, the powdery mildew of cucumber or the red rot fungus of Pythium parasitic on turf can be sterilized.

[0013]

【Example】

(Example 1) Oxidized water produced from a solution containing 500 ppm of sodium hydrogen carbonate A Nafion membrane was used as a cation exchange membrane of a water electrolysis apparatus, and three punched plates made of titanium were used as an anion and an anode. The current collectors were welded to one sheet and then laminated to each other so as to adhere to each other. In a transparent vinyl chloride case, an anode chamber and a cathode chamber were separated by a cation exchange membrane, and the anode and the cathode were housed in the anode chamber and the cathode chamber so as to be in close contact with both sides of the cation exchange membrane.

500 pp of sodium hydrogen carbonate in tap water
5 l of the added solution was prepared in a beaker. The solution was supplied to the anode chamber having an electrode area of 100 cm ² at a flow rate of 1 l / min, and electrolyzed for 45 minutes at a voltage between electrodes of 6 V and a current of 10 A. The solution was circulated during the electrolysis. The physical properties of the obtained oxidizing water are pH 2.7, ORP 1080 mV, N
The amount of a ion was 18 ppm.

Bent grass turfgrass seeds were sown in a 70 mm × 70 mm × 25 mm plastic vat, allowed to grow at room temperature, and then prepared at a cutting height of 10 mm as a test sample. Soil-borne Pythium red rot cultivated with sand as a medium was used as a test bacterium, and a specified amount of the test bacterium was uniformly sprinkled and inoculated on a bentgrass test specimen. Two hours after inoculation of the test bacteria, 30 ml of the oxidizing water produced by the above method was evenly sprayed on the test sample in a shower shape at a temperature of 28 ° C and a relative humidity of 100.
The cells were statically cultivated for 3 days in a constant temperature and constant temperature incubator maintained at%.

After 3 days, the sterilizing power of the oxidizing water was visually inspected.
It was measured by the diseased area percentage of bentgrass. Table 1 shows the test results. (Comparative Example 1) Oxidized water produced only from tap water Sodium hydrogen carbonate was not added to tap water, and otherwise the same operation as in Example 1 was carried out.

The physical properties of the obtained oxidizing water are pH 2.8 and O.
RP1040 mV. Table 1 shows the test results. (Comparative Example 2) Oxidized water produced from a solution containing 500 ppm of sodium chloride 500 ppm of sodium chloride was added to tap water, and otherwise the same operation as in Example 1 was carried out.

The physical properties of the resulting oxidized water were pH 2.6, O.
RP1070 mV and Na ion 170 ppm.
Table 1 shows the test results. (Comparative Example 3) Tap water in which 500 ppm of sodium hydrogen carbonate was added only 500 ppm of sodium hydrogen carbonate was added to tap water, but electrolysis was not performed. Otherwise, the same operation as in Example 1 was carried out.

The test results are shown in Table 1.

[0020]

[Table 1]

[0021]

As described above, according to the method for producing oxidizing water for sterilization of the present invention, plants can be effectively protected from the damage of microorganisms, and the plants can be effectively contained in soil without containing chlorine. Oxidized water for sterilization that can prevent the accumulation of chlorine can be obtained.

Front page continued (72) Inventor Tomokazu Fuchida 4-31 Hondamachi, Kawachinagano-shi, Osaka, Japan Agricultural Chemicals Co., Ltd. (72) Inventor Taku Hirooka 4-31 Hondamachi, Kawachinagano, Osaka, Japan

Claims (3)

[Claims] 1. A method for producing sterilizing oxidized water, which comprises supplying water containing a hydrogen carbonate to an anode chamber of a water electrolysis apparatus and electrolyzing the water to produce oxidized water. 2. The sterilizing agent according to claim 1, wherein the hydrogen carbonate is one or more hydrogen carbonate selected from sodium hydrogen carbonate, potassium hydrogen carbonate and ammonium hydrogen carbonate. Method for producing oxidizing water. 3. Oxidized water for sterilization produced by the method according to claim 1 or 2.