JP4948761B2 - Pesticide spraying method - Google Patents

Description

The present invention relates to a method for spraying a pest control agent.

Conventionally, as a method for spraying pesticides such as insecticides and insecticides, carbon dioxide gas is obtained by dissolving the pesticide in liquefied carbon dioxide (liquefied carbon dioxide) and injecting the liquefied carbon dioxide into the air as a propellant. Along with this, there is known a method of spraying pesticides such as insecticides and insecticides. (For example, see Patent Document 1 and Patent Document 2)

This method sprays chemical-containing liquefied carbon dioxide into the atmosphere from the spray nozzle, and sprays pesticides such as insecticides and insecticides together with carbon dioxide gas by utilizing the rapid expansion when liquefied carbon dioxide vaporizes. Therefore, there are no flammability and environmental problems of solvents and sprays such as oily aerosol formulations, and it can be efficiently and uniformly dispersed in the atmosphere. It is well known as a method of uniformly spraying pesticides such as insecticides and insecticides over a wide space such as a house.

However, on the other hand, the method of spraying liquefied carbon dioxide together with carbon dioxide as a propellant is suitable for the purpose of spraying uniformly in a wide space because it is sprayed in a gaseous form, but in a relatively narrow range. When it is used only on limited spraying targets or spraying surfaces, it is sprayed directly against storage pests such as Kokuzo and Hiratakokunusutomodoki, sanitary pests such as cockroaches, fleas, house dust mites, bedbugs, etc. It is unsuitable for direct application to pests and their surroundings that inhabit a relatively narrow area as in the case, or locally in a limited place such as sterilization or fungicidal.

In addition, since liquefied carbon dioxide is injected as gaseous carbon dioxide, the pest control agent diffuses into the atmosphere together with carbon dioxide after spraying, and there is a problem that the sustainability of the effect on the spray surface is poor.

JP-A-2-258702 JP-A-3-21828

The present invention has been made in view of such circumstances, and there is no flammability or environmental problem, and it is simple and efficient for a limited target pest and its surroundings in a relatively narrow range. It is an object of the present invention to provide a method for spraying pest control agents such as insecticides and insecticides that have good and long-lasting effects.

The present invention provides a method for spraying a pest control agent characterized by spraying particulate carbon dioxide containing a pest control agent.

According to the method of the present invention, since the propellant is carbon dioxide, there is no flammability or environmental problem, and the pesticidal agent is sprayed as particulate carbon dioxide containing the pesticidal agent. Therefore, the pest control agent can be easily and efficiently applied as a topical application to a limited range or target pests, and the effectiveness of the pest control agent on the application surface is effectively maintained. An excellent effect is obtained.

The method of the present invention is a method for spraying a pest control agent comprising spraying particulate carbon dioxide containing a pest control agent.

In the method of the present invention, pesticidal agents are insecticides, insecticides, fungicides, fungicides, and the like that are well known as pesticidal agents, and carbon dioxide at the time of application of such pesticidal agents. Except that the form is particulate, various conditions such as the type of pest control agent to be applied and the drug content are carbon dioxide in the form of carbon dioxide when spraying the conventionally known pest control agent. This is the same as in the case of gas, and there is no particular change.

For example, the content of the pest control agent contained in the particulate carbon dioxide is usually 0.005 to 2% by weight, as in the case of a drug concentration generally applied when the medium is carbon dioxide. The range is preferably 0.05 to 1% by weight.

Moreover, since particulate carbon dioxide containing a pest control agent is usually prepared from liquefied carbon dioxide containing a pest control agent, the pest control agent applied to the present invention has the property of being dissolved in liquefied carbon dioxide. A pest control agent is preferably used.

The property of dissolving in liquefied carbonic acid differs depending on the type of pesticide to be applied, but does not necessarily mean the property of arbitrarily dissolving in liquefied carbonic acid, and can be adjusted to the desired drug content. It is sufficient that the solubility is as follows.

Specific examples of insecticides, insecticides, fungicides and fungicides that are pest control agents include, for example, 1-ethynyl-2-methyl-2-pentenyl chrysanthemate, 2,3,5,6-tetra Fluoro-4-methylbenzyl 2,2-dimethyl-3- (1-propenyl) cyclopropanecarboxylate, 2,3,5,6-tetrafluoro-4- (methoxymethyl) benzyl 2,2-dimethyl-3- (1-propenyl) cyclopropanecarboxylate, 2-methyl-3- (2-propynyl) -4-oxo-cyclopent-2-enyl chrysanthemate, α-cyano-3-phenoxybenzyl chrysanthemate, 2- ( 4-Ethoxyphenyl) -2-methylpropyl 3-phenoxybenzyl ether, 3-phenoxybenzyl chrysanthemer , O, O-dimethyl O-(3-methyl-4-nitrophenyl) phosphorothioate, ethyl alcohol, and 3-iodopropargyl n- butyl carbamate and the like. In addition, although these compounds include those containing optically active substances, it goes without saying that such optically active substances are also included in the present invention.

Pesticides such as insecticides, insecticides, fungicides, and fungicides are used alone or as a mixture of these depending on the purpose and application, and as a spray if necessary. Other commonly used additives may be used in combination as appropriate.

The method of the present invention is a method for spraying a pest control agent comprising spraying particulate carbon dioxide containing such a pest control agent. As a specific embodiment, the method is as described above. Examples thereof include a method using liquefied carbonic acid in which a pest control agent is dissolved in advance to have a predetermined concentration.

In order to dissolve the pest control agent in liquefied carbonic acid, for example, a predetermined amount of the pest control agent is put in a gas cylinder as a pressure vessel, and then a predetermined amount of liquefied carbonic acid is added thereto. Conventionally known methods are applied as they are.

The content of the pest control agent in the liquefied carbonic acid at this time is the same as the content of the pest control agent contained in the particulate carbon dioxide.

The specific method for spraying as particulate carbon dioxide containing a pest control agent is not particularly limited and is arbitrary, but a practical method is to dissolve a pest control agent filled in a pressure vessel. There is a method of spraying the liquefied carbon dioxide formed through a thin tube connected to the spray nozzle.

As is well known in the art, when liquefied carbonic acid dissolved in a pesticide filled in a pressure vessel is directly injected into the atmosphere, the liquefied carbonic acid containing the pesticidal agent is immediately vaporized. The above chemical contained in the liquefied carbon dioxide is dispersed in the air together with the carbon dioxide gas in the form of fine particles due to rapid volume expansion when the liquefied carbon dioxide is gasified.

On the other hand, in the case of the method of spraying via the thin tube connected to the above-mentioned injection nozzle, which is one specific implementation method of the present invention, the liquefaction containing the pest control agent injected from the injection nozzle. Carbon dioxide vaporizes while taking heat of vaporization inside the narrow tube and becomes carbon dioxide gas containing a pest control agent, but the inside of the narrow tube is blocked from the atmosphere except for the outlet, so the inflow of heat from the outside is inhibited, The temperature in the narrow tube is remarkably lowered due to the heat of vaporization, and the carbon dioxide gas containing the pest control agent is rapidly cooled in the narrow tube.

Due to the temperature drop in the narrow tube, the moisture in the air existing in the narrow tube and in the vicinity of the outlet of the narrow tube is cooled, and fine particulate icing with water as a core is formed. The carbon dioxide gas adhered and integrated with the pesticidal agent, and the frozen substances are appropriately combined with each other, and the carbon dioxide containing the pesticidal agent becomes particulate with the icing substance as a core, and is discharged from the capillary tube outlet. Will be sprayed.

In addition, if the temperature in the narrow tube is cooled below the solidification temperature of carbon dioxide due to various conditions such as the injection amount of liquefied carbonic acid, the spray speed, the diameter of the narrow tube, the length of the narrow tube, the shape of the thin tube, The carbon dioxide gas containing the pest control agent once vaporized is solidified in the form of particles, for example, snowflakes, to form solid carbonic acid. It can be dispersed as carbon dioxide from the outlet of the narrow tube.

In the present invention, the dispersion of particulate carbon dioxide refers to the dispersion of particulate matter in which carbon dioxide containing a pesticide is attached to and integrated with particulate icing with such moisture as the core, Carbon dioxide gas containing a pest control agent itself means dispersion of solid carbonic acid solidified in the form of particles, for example, snowflakes, but it is usually sprayed only as the former or as a mixture of the former and the latter. In many cases, the ratio of the two when sprayed as a mixture is arbitrary.

As an apparatus for carrying out such a method, for example, as shown in the schematic diagram of FIG. 1, a pressure vessel 1 filled with liquefied carbon dioxide dissolved with a pest control agent, and a pressure communication pipe 2 are used. There is a spraying device composed of an injection nozzle 3 connectable to the pressure vessel and a thin tube 4 connected to the injection nozzle.

Here, a pressure vessel (cylinder) filled with liquefied carbon dioxide obtained by dissolving a pest control agent other than the portion of the narrow tube 4 and an injection nozzle connectable to the pressure vessel through a pressure communication tube. The configuration is basically the same as that of a device that sprays a known particulate pesticide together with carbon dioxide.

As the pressure vessel, a metal cylinder such as steel or aluminum is usually used, and its size is appropriately selected depending on the filling amount of liquefied carbonic acid. About 5-7kg is filled.

Since pressure-resistant communication pipes are usually required to be flexible, pressure-resistant rubber pipes that are sometimes reinforced with synthetic fibers such as nylon fibers or polyester fibers or steel cords are often used.
The length of the pressure communication pipe is appropriately set depending on the purpose of use and is not particularly limited.
Further, the tube diameter is not particularly limited, and is appropriately determined depending on the size of the cylinder, the length of the communication tube, and the like.

For the injection nozzle 3, a conventionally known one that can be freely operated to open and close and open and close the opening / closing valve 8 of the flow path in the injection nozzle by a gripping operation of a hand lever, for example, is applied.
The size (hole diameter) of the spray nozzle of the spray nozzle 3 is usually 0.1 to 1 mm.

The thin tube 4 is closely connected so that the hollow portion 6 of the thin tube communicates with the flow path 7 in the injection nozzle 3 and the tip portion (injection port) 5 of the injection nozzle 3 is located in the thin tube hollow portion 6. Yes.

The connection method is arbitrary, and the inner week surface of the thin tube may be directly inserted into the outer peripheral surface of the tip portion of the injection nozzle, or may be screwed on both sides, or may be completely joined by welding or adhesion. Even in this case, it is preferable that the injection body from the injection port 5 be closely joined so as to circulate in the narrow tube without leaking to the outside.

As described above, the thin tube 4 is a hollow tube, and the material thereof is not particularly limited, such as metal or plastic. For example, a metal tube such as a steel tube, an aluminum tube, a copper tube or a stainless tube, a plastic such as a vinyl chloride tube or a polyethylene tube. In general, these are often used as straight pipes in which the center line of the flow path 7 in the jet nozzle and the hollow portion 6 of the narrow pipe is substantially in a straight line after being connected to the jet nozzle.

The thickness (thickness) of the thin tube 4 is not particularly limited as long as the thin tube 4 has rigidity sufficient to physically maintain the state where the thin tube is connected to the injection nozzle, but the method of the present invention is not limited. Utilizes the fact that the liquefied carbon dioxide sprayed from the spray nozzle vaporizes into carbon dioxide gas while taking heat of vaporization in the narrow tube, and at the same time the temperature inside the narrow tube is lowered by the vaporized heat that is taken away and the inside of the narrow tube is cooled rapidly. Therefore, the thickness to the extent that the cooling is not hindered by the inflow of heat in the atmosphere from the outer peripheral surface of the thin tube is appropriately determined according to the respective conditions such as the type of the material of the thin tube, the hollow diameter, the length of the thin tube, Usually, it is about 0.1 to 10 mm.

The inner diameter of the thin tube needs to be larger than the diameter of the injection port 5 of the injection nozzle, but if it is too large, the volume of the hollow portion becomes too large to obtain the effect as a thin tube and the cooling effect is insufficient. Therefore, in general, the maximum portion is 100 mm or less.

The inner diameter of the thin tube is larger than that of the injection port 5, and the same diameter may be provided from the connecting portion with the injection nozzle to the thin tube outlet, as shown in FIG. The portion may be increased stepwise, or the portion close to the injection port may be a trumpet shape and may have the same diameter from the outlet side of the narrow tube, and is set as appropriate.
Further, a protrusion or a concave portion may be appropriately provided on the inner wall of the thin tube hollow portion 6 to prevent the propelling gas from moving straight forward and to reduce the flow velocity thereof.

The length of the narrow tube varies depending on conditions such as the injection amount and pressure, the thickness of the narrow tube material, the inner diameter of the narrow tube, and the hollow shape in the narrow tube, but if it is too short, the vaporized carbon dioxide gas is sprayed out of the narrow tube as it is. Therefore, the length is usually not less than 50 mm, preferably not less than 80 mm.

On the other hand, if the length is too long, not only is the operation inconvenient, but the inside of the narrow tube is cooled too much, and the production rate of solid carbonic acid is too good. Usually, it is 500 mm or less, preferably 250 mm or less.

The liquefied carbon dioxide containing the pest control agent ejected from the spray nozzle using such a spraying device is vaporized while depriving the heat of vaporization in the narrow tube, and at the same time, the carbon dioxide gas itself due to the deprived heat of vaporization. Is cooled and solidified in the narrow tube, and can be sprayed from the outlet of the narrow tube so that particulate carbon dioxide containing a pest control agent is poured.

The spraying method varies depending on the infestation status of the target pests, fungi, fungi, the area to which the chemical is sprayed, the amount of liquefied carbon dioxide sprayed per unit time, etc. This is carried out by spraying liquefied carbon dioxide containing a pest control agent from an appropriate height above the surface to be sprayed, for example, a height of about 50 to 100 cm, with the thin tube outlet of the device directed toward the spray surface. The carbon dioxide containing the pest control agent in the form of particles can be intensively dispersed from the narrow tube outlet around a relatively limited surface to be dispersed, and can be dispersed by moving the narrow tube outlet. The surface can be moved and adjusted freely.

According to such a method, since the liquefied carbon dioxide, which is a propellant, is in the form of particulate carbon dioxide when sprayed, the target pest is injected at a higher pressure than when conventional gaseous carbon dioxide is jetted at a high speed. Without spraying or diffusing into the atmosphere immediately after injection and reducing the concentration of the drug, the pest control agent can be intensively sprayed in a limited area.

In addition, the pesticide contained in the particulate carbon dioxide that has poured onto the surface to be sprayed remains on the spray surface in the form of solid particles and is gradually released, so that the effectiveness of the insecticide / insecticide is effectively maintained. It will be.

EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, it cannot be overemphasized that this invention is not what is limited to this Example.

Example 1
<Production example>
14 g of 2,3,5,6-tetrafluoro-4-methylbenzyl 2,2-dimethyl-3- (1-propenyl) cyclopropanecarboxylate (compound 1) was placed in a steel cylinder having an internal volume of 10 liters. 7 kg of liquefied carbonic acid was filled into a carbon dioxide gas preparation. (Drug concentration: 0.2%)
An injection nozzle in which a stainless steel metal pipe having an inner diameter of 7 mm and a length from the injection port to the tip of 240 mm is attached to the tip of the nozzle through a pressure gauge and a pressure resistant rubber tube having an inner diameter of 5 mm and a length of 1.5 m. (Jet diameter: 0.2 mm) was connected to form a spraying device.

<Spreading process>
A filter paper for measuring the amount of adhering drug (Advantech No. 5B 8 × 8 cm) is placed on the floor surface of a peat gradient chamber having a length of 1.7 m, a width of 1.7 and a height of 2.1 m. (1) -No. (11) A glass petri dish of (A) to (D) arranged in a distributed manner at the position of (11) and further arranged at the position shown in FIG. Each head was placed and placed.
Thereafter, carbon dioxide gas composition is jetted from a height of 60 cm above the central portion, and particulate matter in which carbon dioxide containing an insecticide / insecticide is attached to and integrated with particulate icing with water as the core, and A mixture of carbon dioxide containing insecticide / insecticide and solid carbonic acid solidified in the form of snowflakes was sprayed for 30 seconds.
This spraying test was performed twice by changing the injection amount by adjusting the opening of the valve.

<Evaluation>
Ten minutes after spraying, it was confirmed that oxygen dioxide was sublimated or vaporized, and the test insects were taken out from the three petri dishes, transferred to another clean container, and determined for life or death.
In addition, add 20 new larvae to each of the original petri dishes from which the test insects were taken out, remove them one hour later, transfer them to another clean container, and determine whether they are alive or dead. confirmed.
The determination of life or death was made based on the movement and immobility 24 hours after the transfer to another container.
This evaluation was performed for each spraying process.

In addition, when the test insect was removed, the No. (1) -No. The filter paper of (3) is No. 1 hour later. (4) -No. The filter paper of (7) is No. 2 hours later. (8) -No. The filter paper of (11) was collected.
The collected filter paper was added with 5 ml of acetone to extract the drug, and the extract was subjected to gas chromatography analysis under the following conditions to measure the amount of drug attached, and the amount of drug attached per unit area was calculated based on the measured value. .

<Gas Chromatic Conditions>
Model: Shimadzu GC-14A
Detector: Hydrogen flame ionization detector (FID)
Column: 1.5% Silicon OV-17 Shimalite W
(AW-DMCS) 80/100 mesh, φ2.6mm × 1m
Column temperature: 160 ° C
Inlet temperature, detector temperature: 220 ° C
Carrier gas: nitrogen 50 ml / min, hydrogen 0.7 kg / cm ²
Air 0.7 kg / cm ²
Quantitative calculation method: Absolute calibration curve method

Table 1 shows the injection amount of the carbon dioxide preparation for each spraying test and the amount of drug adhered per unit area in each filter paper.
In addition, Table 2 shows the supine death rate (lethal rate) of the test insect for each spray test.
In Table 2, the supine lethality indicates the proportion of those who cannot be normally walked by observing after 24 hours, and the lethality is the proportion of those that do not respond at all even when a stimulus is applied. Indicates.

Example 2
2,3,5,6 instead of 2,3,5,6-tetrafluoro-4-methylbenzyl 2,2-dimethyl-3- (1-propenyl) cyclopropanecarboxylate (Compound 1) in Example 1 -Tetrafluoro-4- (methoxymethyl) benzyl 2,2-dimethyl-3- (1-propenyl) cyclopropanecarboxylate (Compound 2) was used in the same manner as in Example 1 except that a carbon dioxide preparation was prepared. The results shown in Tables 1 and 2 were obtained by carrying out the scattering treatment (once) and evaluation.

Example 3
Instead of 2,3,5,6-tetrafluoro-4-methylbenzyl 2,2-dimethyl-3- (1-propenyl) cyclopropanecarboxylate (Compound 1) in Example 1, α-cyano-3-phenoxy A carbon dioxide preparation was prepared, sprayed (one time), and evaluated in the same manner as in Example 1 except that 42 g of benzyl chrysanthemate (Compound 3) was used, and the results shown in Tables 3 and 4 were obtained.

As a result of the above, it was found that the drug can be sprayed almost intensively on the spray target surface, and its residual effect is excellent.

The conceptual diagram of the dispersion device applied to the method of this invention is shown. It is a conceptual diagram which shows the example of the joining state of the injection nozzle and a thin tube in the spraying apparatus shown in FIG. The arrangement | positioning state of the filter paper for a measurement in the case of the dispersion | spreading process in each Example of this invention is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure-resistant container 2 Pressure-resistant communication pipe 3 Injection nozzle 4 Narrow tube 5 Injection port 6 Narrow tube hollow part 7 Injection nozzle flow path 8 Injection nozzle on-off valve (1)-(11) Filter paper arrangement position (A)-(D) Glass petri dish placement position

Claims (3)

Moisture to particulate frost that core, you contain pesticide carbon dioxide is deposited, the method of application of pesticides, characterized in that spraying the particulate material that is integrated. The method for spraying a pest control agent according to claim 1, wherein the pest control agent is an insecticide, an insecticide, a fungicide, or a fungicide. By spraying liquefied carbonic acid dissolved in a pressure-resistant container through a thin tube connected to a spray nozzle, pesticides are formed on particulate icing with water as the core. you containing control agent carbon dioxide is deposited, spraying method of claim 1 pest control agent, wherein the spraying as a particulate material that is integrated.

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