Drug diffusion methods

Abstract

This invention provides a chemical diffusion method that allows for chemical treatment at wider application intervals using a conventional liquid transfer pump, and improves the effectiveness and workability of chemical treatment by improving the uniformity of chemical distribution in the soil. [Solution] A method for diffusing a chemical agent, comprising: an installation step of installing a void structure having voids through which a chemical agent can pass in the soil; a chemical injection port formation step of forming a chemical injection port for injecting the chemical agent from the ground surface into the void structure; and a diffusion step of injecting the chemical agent into the chemical injection port and diffusing the chemical agent into the soil around the void structure, wherein the void structure is made of a material with a thickness of 1 cm or more and a void ratio of 30% or more.

Description

Technical Field

[0001] The present invention relates to a method for drug diffusion, and particularly to a method for drug diffusion that uses an anti-termite drug for soil anti-termite treatment as a drug and can diffuse this drug into the soil.

Background Art

[0002] As a means for preventing termite damage to wooden houses, when a wooden house is newly built or several years after new construction, the foundation and base parts of the wooden house and the soil around these are treated with an anti-termite drug.

[0003] For example, a process of drilling holes in the tile joints of the entrance steps, concrete such as dog runs, etc. with a drill and then injecting an anti-termite drug (drilling and injection process) is generally performed.

[0004] In addition, there is an anti-termite treatment method in which a pipeline is installed in advance in the soil on the outer periphery of a building, and a drug is poured into the pipeline from an injection port (for example, Patent Document 1). With this anti-termite treatment method, the risk of damage to tile joints, concrete, etc. due to drill holes in the case of the drilling and injection process can be eliminated, and by providing an injection port at the end of the pipeline, the soil on the outer periphery of the building can be treated with an anti-termite drug.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the case of perforation injection treatment, depending on the soil type, the horizontal spread of the termite control agent in the soil is approximately 20 cm in radius from the injection point. Therefore, perforation injection treatment requires one location approximately every 30-50 cm, making the work efficiency of the termite control treatment poor. Furthermore, in the case of perforation injection treatment, the spread of the termite control agent in the depth direction in the soil is close to an inverted triangle shape with the injection point at the center of the base, and the penetration of the termite control agent into the soil becomes shallower the further away from the injection point, making uniform treatment in the soil difficult. In addition, there is a risk of damaging buried pipes under concrete such as tile joints in entrance halls or walkways, for each location where perforation injection treatment is performed.

[0007] Furthermore, a problem with Patent Document 1 is that the pipeline pipes have small holes spaced about 10 to 30 cm apart, and the termite control agent spreads into the soil through these holes. However, the resistance to pumping the termite control agent into the pipes is high, requiring a higher-pressure pump than the one used when directly treating the termite control agent in the soil. In addition, there is an inlet surrounded by a protective box on the ground, but if there is a problem with the inlet, the termite control agent cannot be pumped into the pipeline, making it impossible to perform the termite treatment itself.

[0008] The present invention aims to address the above-mentioned problems and provide a method for dispersing chemicals that allows for wider application intervals using a commonly used liquid transfer pump, and improves the effectiveness and workability of chemical treatment by ensuring more uniform dispersal of the chemicals in the soil. [Means for solving the problem]

[0009] To solve the above problems, the present invention provides a drug diffusion method comprising: an installation step of installing a void structure having voids through which a drug can pass in the soil; a drug injection port formation step of forming a drug injection port for injecting the drug from the ground surface into the void structure; and a diffusion step of injecting the drug into the drug injection port and diffusing the drug into the soil around the void structure, wherein the void structure is made of a material with a thickness of 1 cm or more and a void ratio of 30% or more.

[0010] The installation step may also be a step of installing the void structure in the soil at a depth of 5 cm to 80 cm from the ground surface, such that the thickness direction and vertical direction of the void structure are substantially parallel.

[0011] The installation step may also be a step of installing the void structure in the soil at a depth of 5 cm to 80 cm from the ground surface, such that the thickness direction and vertical direction of the void structure are substantially perpendicular to each other.

[0012] The aforementioned void structure may be a structure in which a plastic three-dimensional mesh molded product is covered with a nonwoven fabric sheet.

[0013] The aforementioned void structure may be a structure made of urethane foam.

[0014] The location where the aforementioned void structure is installed may be at least one of the following: in the soil beneath the entrance steps of the building, in the soil beneath the back entrance, in the soil beneath the entrance floor, or in the soil around the perimeter of the foundation. [Effects of the Invention]

[0015] According to the present invention, a high-pressure liquid transfer pump is not required, and chemical treatment can be performed at wider intervals using a conventional liquid transfer pump. Furthermore, by improving the uniformity of the chemical distribution in the soil, a chemical diffusion method can be provided that can improve the effectiveness and workability of chemical treatment. [Brief explanation of the drawing]

[0016] [Figure 1] These are photographs and schematic diagrams showing the results of evaluating the spread of the chemical agent when it was applied to the soil using the chemical diffusion method of Example 1. [Figure 2] These are photographs and schematic diagrams showing the results of evaluating the spread of a chemical agent when it was applied to the soil using the chemical diffusion method of Comparative Example 1. [Modes for carrying out the invention]

[0017] Hereinafter, the drug diffusion method according to the present invention will be described. Note that the present invention is not limited to the following examples.

[0018] The drug diffusion method includes the following installation process, drug injection port formation process, and diffusion process.

[0019] [Installation Process] This process is a process of installing a void structure in the soil. For example, the soil can be dug to form a hole with a predetermined depth and width, the void structure can be installed so that it is in the desired position, and then the void structure can be installed in the soil by covering the void structure with soil and filling it back.

[0020] Regarding how much soil to dig and what size of hole to dig, it can be appropriately adjusted according to the size of the void structure, the depth to be installed, etc.

[0021] In the installation process, for example, the void structure is installed so that the thickness direction and the vertical direction of the void structure are substantially parallel. By installing it in this way, the drug injected into the void structure spreads horizontally particularly in the soil, and the drug can penetrate and diffuse over a wide range. Substantially parallel includes a completely parallel state, but also includes the case where the void structure is installed with a slope of about 0 to 10 degrees from the horizontal state in consideration of the soil and the installation site conditions.

[0022] Also, the void structure may be installed so that the thickness direction and the vertical direction of the void structure are substantially perpendicular. In this case, the drug can penetrate deep into the soil. <(

[0023] Furthermore, the depth to which the chemical penetrates and diffuses in the soil is, for example, about 50 cm to 1 m from the surface, and the void structure is installed to correspond to that depth. In the installation process, for example, the void structure is installed in the soil at a depth of 5 cm to 80 cm from the surface. However, when the chemical penetrates and diffuses beneath the foundation of a building, the depth to which the chemical penetrates and diffuses will vary depending on the depth of the foundation, and the depth to which the void structure is installed will also vary.

[0024] In this process, for example, void structures can be installed by using excavation construction machinery such as shovels, pickaxes, and excavators as appropriate to dig holes and backfill them.

[0025] <Void structure> As a void structure, it must have a thickness of 1 cm or more and a void ratio of 30% or more that allows the chemical to pass through. If the thickness is less than 1 cm, the amount of chemical that can be contained in the void structure will be small, and the chemical may not be able to penetrate and diffuse sufficiently into the soil. There are no particular upper limits on thickness or void ratio, but for example, the upper limit of thickness can be set to 15 cm and the upper limit of void ratio to 80%.

[0026] As for the void structure, for example, a mat-type structure made of a plastic three-dimensional mesh molded product with a thickness of 20 mm to 50 mm, a width of 250 mm to 500 mm, and a length of 50 cm to 3 m can be used. Specifically, a three-dimensional mesh molded product with a void ratio of 80% or more, made by extruding polypropylene resin into fibers with a diameter of about 2 mm, can be used.

[0027] Furthermore, the aforementioned void structure may be a structure made of urethane foam. For example, a structure made of polyester urethane foam with 20 or fewer cells per 25 mm can be used. For example, it can be processed into a mat-type structure with a thickness of 20 mm to 50 mm, a width of 250 mm to 500 mm, and a length of 50 cm to 3 m, and used as a void structure.

[0028] Furthermore, the void structure can be in the shape of a mat or a tube, or a long steel wool pad or similar material can be processed into the desired shape and used as the void structure.

[0029] <Location of the air gap structure> The location for installing the void structure is anywhere there is soil to be treated with chemicals, and this location is not particularly limited. For example, at least one of the following locations could be the soil under the entrance steps of a building, the soil under the back door, the soil under the entrance floor, or the soil around the perimeter of the foundation.

[0030] [Process for forming drug injection port] This process involves creating an injection port for injecting chemicals into a void structure from the ground surface. Normally, void structures are buried in the soil, making it difficult to inject chemicals directly into them. Therefore, an injection port is created when it becomes necessary to inject chemicals, such as during the construction or renovation of a building. The injection port may be formed, for example, so that it opens at the center of the void structure.

[0031] For example, the simplest type of injection port intended for a chemical agent is a hole drilled in the concrete. If the injection port is to be prepared in advance, one could, for example, install a straw-like tube that reaches the void structure during concrete pouring, and seal the opening with silicone sealant until use. Alternatively, one could drill a hole from the buried location of the void structure at the time of use, and use the resulting hole as the injection port.

[0032] [Diffusion process] This process involves injecting the chemical into the chemical injection port and diffusing the chemical into the soil surrounding the void structure. The method of injecting the chemical is not particularly limited; it can be done by injecting the chemical through a pre-installed injection port or an injection port created by drilling using a chemical delivery pump, which is normally used in soil injection treatment.

[0033] When the chemical is injected into the chemical injection port, the injected chemical is dispersed into the soil surrounding the void structure via the void structure.

[0034] <Medicine> In terms of chemicals, termite control agents can be mentioned from the perspective of treating the soil to prevent termites. However, this is not the only option; if the purpose is insect control, insecticides can be mentioned, and if the purpose is soil improvement, soil conditioners can be mentioned.

[0035] As described above, the drug diffusion method of the present invention can be expected to have the following effects.

[0036] In the conventional method of perforation injection, the horizontal spread of the chemical in the soil is approximately 20 cm in radius from the injection site. Therefore, perforation injection is required at intervals of approximately 30-50 cm, resulting in poor workability for termite control. However, with the present invention, by adjusting the dimensions and size of the void structure, the horizontal spread of the chemical in the soil from each chemical injection site can be increased to a radius of 40 cm or more. This allows for fewer chemical injection sites than in the conventional method, and thus reduces the number of perforations.

[0037] By injecting the chemical agent into one location within the void structure, the chemical agent can be uniformly penetrated into the soil in the depth direction, compared to conventional methods that do not use void structures.

[0038] By burying the void structure, for example, between concrete and piping, the risk of accidentally damaging the piping during drilling can be reduced.

[0039] Regardless of where the chemical is injected into the void structure, the resistance to transporting the chemical is small, so a chemical transport pump used in normal soil injection treatments can be used.

[0040] In the case of Patent Document 1, since there is only a chemical injection port at the end of the pipeline, if there is a problem with the injection port, the termite control agent cannot be delivered to the pipeline, and the termite control treatment itself cannot be performed. However, in the present invention, as long as the agent reaches the void structure through drilling or the like, termite control treatment is possible.

[0041] The role of common nonwoven fabrics and open-cell foams (sponges, etc.) buried in the ground for termite control (for example, Patent Documents 1 and 2) is primarily considered to be both "retention" and "release" of the chemical agent. However, they are unsuitable for the purpose of "liquid delivery" of the chemical agent, which is the objective of this invention, because they are either too dense or too thin. On the other hand, in the case of the present invention, by employing a porous structure suitable for the liquid delivery of the chemical agent, the chemical agent can be diffused and penetrated more widely in the horizontal direction within the soil.

[0042] When a chemical agent is injected into a void structure, it spreads throughout the entire structure. As a result, the injected chemical agent diffuses and penetrates from the entire surface of the void structure into the soil, forming a chemical penetration layer over a wide area of ​​the soil. [Examples]

[0043] The present invention will be described in more detail below with reference to examples, but the present invention is not limited in any way to the following examples.

[0044] In the embodiment, the drug diffusion method of the present invention was implemented, and a drug permeable layer was formed in the soil to evaluate the diffusivity and permeability of the drug.

[0045] [Example 1] <Medications used> Ecolofen emulsion was used. Note that, unless specifically advertised as having soil-dispersible properties, the degree of soil dispersion of other termite control agents is similar to that of Ecolofen emulsion.

[0046] <Air gap structures used> A windproof and breathable mat was used. Its dimensions are 2 cm thick, 10 cm wide, and 65 cm long.

[0047] <Soil diffusion treatment of chemicals> The black soil was excavated to a depth of 5 cm from the surface, and a 2 cm thick void structure was installed so that the thickness direction of the void structure was parallel to the vertical direction, that is, so that the mat surface of the void structure was parallel to the horizontal direction. Then the void structure was backfilled with black soil (installation process). After that, a straw cut to approximately 5 cm was passed through the void structure vertically from the surface so as to be in contact with the center of the void structure to form one chemical injection port (chemical injection port formation process). Then, 2 L of chemical was injected into the chemical injection port and the chemical was diffused into the soil around the void structure (diffusion process).

[0048] Figure 1 shows photographs and schematic diagrams illustrating the evaluation of the spread of the chemical agent when it is applied to soil using the above-mentioned diffusion treatment. The photograph in Figure 1(a) shows a cross-section of the soil passing through the center of a void structure, taken from a hole dug in the soil 30 minutes after the diffusion process.

[0049] The schematic diagram shown in Figure 1(b) traces the outline of the soil that has changed color to a wet color due to the chemical in the photograph of this cross-section, and the area within this outline is designated as the chemical treatment layer, and the dimensions of the cross-sectional area of ​​the chemical treatment layer are measured. The triangular part is the chemical injection port 10, and a void structure 30 exists within the chemical treatment layer 20. The width 31 of the void structure 30 is approximately 65 cm, the infiltration depth 21 of the chemical treatment layer 20 is approximately 22 cm, the infiltration width 22 is approximately 80 cm, the infiltration depth 23 in the area where the infiltration width is approximately 75 cm or more is approximately 10 cm, and the symbol 40 indicates the ground line.

[0050] [Comparative Example 1] Except for not using a void structure and spraying the chemical without forming a chemical injection port by inserting the tip of the chemical injection nozzle into the ground surface, the chemical was diffused into the soil in the same manner as in Example 1, and a cross-section of the soil was photographed as shown in Figure 2 (Figure 2(a)), and a schematic diagram (Figure 2(b)) was created. The triangular part is the chemical injection port 50, the penetration depth 61 of the chemical treatment layer 60 is approximately 12 cm, the penetration width 62 is approximately 40 cm, the penetration depth 63 in the area with a penetration width of approximately 35 cm or more is approximately 3 cm, and the reference numeral 40 indicates the ground line.

[0051] [result] Comparing the results in Figures 1 and 2, it was found that diffusing the agent into the soil via the void structure allowed for wider diffusion of the agent compared to the case without the void structure. In the horizontal direction, the diffusion of the agent was approximately 80 cm for Example 1 and approximately 40 cm for Comparative Example 1, indicating that Example 1 diffused about twice as far as Comparative Example 1. In the vertical direction, the diffusion of the agent was approximately 22 cm for Example 1 and approximately 12 cm for Comparative Example 1, indicating that Example 1 penetrated and diffused into the ground about 1.8 times more than Comparative Example 1.

[0052] Furthermore, in Comparative Example 1, the spread of the drug in the depth direction within the soil took on a shape close to an inverted triangle with the injection point at the center of the base. The further away from the injection point, the shallower the penetration of the drug into the soil in the depth direction became, making uniform treatment in the soil difficult (Figure 2). On the other hand, in Example 1, a sufficient drug treatment layer was formed in the depth direction within the soil even at a distance from the injection point (Figure 1). [Industrial applicability]

[0053] Based on the above results, the present invention's method for dispersing chemicals allows for wider application intervals even when using a conventional liquid transfer pump, and improves the uniformity of chemical distribution in the soil, thereby enhancing the effectiveness and workability of chemical treatment, making it industrially useful. [Explanation of Symbols]

[0054] 10 Drug injection port 20 Chemical treatment layer 21 Penetration depth 22 Penetration width 23 Penetration depth 30 Cavity structure 31 width 40 Grand Line 50 Drug injection port 60 Chemical treatment layer 61 Penetration depth 62 Penetration width 63 Penetration depth

Claims

1. Installation process involves installing a void structure in the soil that has voids through which chemicals can pass, A drug injection port formation step is to form a drug injection port for injecting the drug into the void structure from the ground surface, The process includes a diffusion step of injecting the agent into the agent injection port and diffusing the agent into the soil surrounding the void structure, A method for diffusing a drug, wherein the aforementioned void structure is made of a material with a thickness of 1 cm or more and a void ratio of 30% or more.

2. The method for diffusing a drug according to claim 1, wherein the installation step is to install the void structure in the soil at a depth of 5 cm to 80 cm from the ground surface such that the thickness direction and the vertical direction of the void structure are substantially parallel.

3. The method for diffusing a drug according to claim 1, wherein the installation step is to install the void structure in the soil at a depth of 5 cm to 80 cm from the ground surface such that the thickness direction and vertical direction of the void structure are substantially perpendicular to each other.

4. The drug diffusion method according to claim 1, wherein the aforementioned void structure is a structure in which a plastic three-dimensional mesh molded product is covered with a nonwoven fabric sheet.

5. The method for diffusing a drug according to claim 1, wherein the void structure is a structure made of urethane foam.

6. The method for diffusing a chemical agent according to claim 1, wherein the location where the void structure is installed is at least one of the following: in the soil under the entrance steps of the building, in the soil under the back door, in the soil under the entrance floor, or in the soil around the perimeter of the foundation.

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