Pest control methods

Abstract

To provide a method for effectively controlling a pest in a space where the pest may enter for overwintering.SOLUTION: Holding means 2 holding a pest control agent having a transpiration property is prepared in a space R in which the room temperature rises from below the pest hibernation start temperature to above the pest activity start temperature. After that, the amount of the pest control agent that transpires from the holding means 2 into the space R is increased by raising the room temperature. Pests that have started to become active when the room temperature reaches or exceeds the activity start temperature are controlled with the pest control agent.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for controlling pests in space using a pest control agent having transpiration properties. [Background technology]

[0002] For example, a pest control method is known in which a pest control agent having vapor pressure of 2×10 at 30° C. is used to control pests in a space. -4 ~1×10 -2 The method describes a method of controlling pests in a space by releasing 0.01 to 40 mg of pest control agent at a concentration of mmHg per 8 tatami mats, causing the agent to adhere to the inner surfaces of floors and walls, and then allowing the pest control agent to re-evaporate.

[0003] On the other hand, for example, Patent Document 2 discloses a method of preventing the invasion of pests by applying a pest control agent selected from hardly volatile pyrethroid compounds. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-35569 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-155774 Summary of the Invention [Problem to be solved by the invention]

[0005] When using a pest control agent that evaporates at room temperature, as in Patent Document 1, there is the advantage that it can be evaporated throughout the entire space and be effective, but there is also the disadvantage that the agent may continue to be evaporated even when there are no pests in the space and be wasted, and as a result, the duration of its effectiveness is relatively short. Therefore, the method in Patent Document 1 is used when pests are discovered in a space or when it is thought that there is a high possibility that pests are present in the space.

[0006] On the other hand, when a hardly volatile pest control agent with low transpiration properties is used as in Patent Document 2, although there is an advantage in that the effect lasts for a relatively long time, there is a disadvantage in that the pest control agent does not transpire into the space, so it cannot be effective throughout the space, and is only effective in the area where it is applied.

[0007] Incidentally, some types of pests may enter spaces to overwinter and hibernate during the winter (when temperatures are low). In this regard, it may be possible to prevent pests from entering spaces using an intrusion prevention method such as that described in Patent Document 2, but in reality, it is often impossible to completely prevent pests from entering.

[0008] Even if pests are allowed to invade a space, if they are noticed immediately, there is a possibility that they can be exterminated by treating the space with the method described in Patent Document 1. However, if they are noticed too late, the pests will enter gaps to hibernate, making them difficult to find, and there is a high possibility that they will not be noticed. In this case, there is no opportunity to treat the space with the method described in Patent Document 1 in the first place.

[0009] Then, when the warm season arrives, pests emerge from hibernation and begin to become active all at once, but since you may not notice this right away, there is a risk that various pest damage will occur within the space without you even realizing it.

[0010] The present invention has been made in consideration of the above points, and its object is to provide a method for effectively controlling pests in spaces into which the pests may enter to overwinter. [Means for solving the problem]

[0011] To achieve the above object, a first aspect of the present disclosure can be premised on a pest control method for controlling pests in a space. A holding means for holding a transpiration-type pest control agent is prepared in a space where the room temperature rises from below the hibernation onset temperature at which target pests begin hibernation to above the activity onset temperature at which the hibernating pests begin to become active, when the room temperature is below the hibernation onset temperature. Subsequently, as the room temperature rises, the amount of the pest control agent transpire from the holding means into the space increases, and pests that begin to become active when the room temperature rises above the activity onset temperature are controlled.

[0012] That is, when the room temperature of the space is low and below the hibernation onset temperature, pests are hidden deep within gaps and other areas, and their activity is reduced, so even if a pest control agent is sprayed into the space, the effect is low. In this regard, according to the present disclosure, when the room temperature of the space rises and pests begin to become active and crawl out of gaps and other areas, the amount of pest control agent evaporating from the holding means increases, and the concentration of the pest control agent in the air within the space increases. In other words, the timing at which hibernating pests begin to become active can be synchronized with the timing at which the amount of pest control agent evaporating can be increased. This allows pests that have been hibernating in the space to be effectively controlled when they begin to become active. Furthermore, when the room temperature of the space is low, the amount of pest control agent evaporating from the holding means is lower than when the room temperature is high, thereby reducing unnecessary evaporation of the pest control agent when the control effect is low.

[0013] In a second aspect of the present disclosure, a vapor pressure at 30°C of 1 x 10 -5 ~1×10 -3 The pest control agent can be held by the holding means at a pressure of mmHg.

[0014] According to this configuration, a pest control agent having a vapor pressure within the above range hardly evaporates below the hibernation onset temperature, but evaporates moderately when the temperature reaches or near the activity onset temperature, thereby further enhancing the above-mentioned control effect.

[0015] In a third aspect of the present disclosure, the pest control agent is at least one of transfluthrin and metofluthrin.

[0016] In other words, by holding at least one of transfluthrin and metofluthrin in the holding means, the amount of transpired at temperatures below the hibernation onset temperature is extremely small, preventing unnecessary consumption of the drug, while at the same time, when the temperature reaches or near the activity onset temperature, a sufficient amount is transpired, providing high control efficacy.

[0017] In a fourth aspect of the present disclosure, the hibernation onset temperature may be 15°C, and the activity onset temperature may be 20°C.

[0018] In a fifth aspect of the present disclosure, the space may be a non-residential space where no human lives.

[0019] That is, spaces occupied by people are often kept at a certain temperature or higher even during the winter by heating devices or the like, so pests rarely hibernate in such spaces. However, in spaces not occupied by people, such as warehouses, the room temperature drops below the hibernation onset temperature during the winter, causing pests to hibernate. Then, with the arrival of spring, the room temperature rises and the pests become active, potentially causing pest damage to cargo in the warehouse. The method of the present disclosure is particularly suitable because it can be used in such spaces not occupied by people, thereby effectively controlling pests that have woken up from hibernation and become active.

[0020] In a sixth aspect of the present disclosure, when the temperature is below the hibernation onset temperature, the pest control agent is attached to the floor or the inner surface of the wall of the space, making the floor or wall the retention means, and as the room temperature rises, the amount of the pest control agent evaporating from the inner surface of the floor or wall is increased.

[0021] According to this configuration, the inner surfaces of the floors and walls that divide the space can be used as the holding means, so there is no need to provide a dedicated holding means to carry out the pest control method, and the pest control method can be carried out easily. In addition, since the inner surfaces of the floors and walls have a large surface area, the pest control agent can be efficiently evaporated from a large surface area.

[0022] In a seventh aspect of the present disclosure, the pest control agent is contained in an aerosol container, and the pest control agent is sprayed from the aerosol container toward the floor or the inner surface of the wall of the space, thereby adhering to the floor or the inner surface of the wall.

[0023] This configuration allows the pest control agent to be easily applied to a wide area of ​​the inner surface of the floor or wall.

[0024] In an eighth aspect of the present disclosure, when the room temperature inside the space and the temperature outside the space are below the hibernation initiation temperature at which pests to be controlled start hibernation, an impregnated body impregnated with the pest control agent is placed so that it is exposed to outside air taken in through an outside air intake hole provided in a wall partitioning the space. Thereafter, outside air is taken in through the outside air intake hole and the temperature outside the space rises, thereby increasing the amount of the pest control agent transpiration into the space from the impregnated body, and when the room temperature reaches or exceeds the activity initiation temperature of the hibernating pests, the pests that have started to become active are controlled.

[0025] That is, the temperature of the outside air taken in through the outside air intake hole fluctuates, for example, with the change of seasons, and may rise from below the hibernation start temperature to above the activity start temperature. As the temperature of the outside air taken in through the outside air intake hole increases, the amount of pest control agent transpiration from the impregnated body increases compared to when it is low. Furthermore, when the outside air temperature rises above the activity start temperature, the room temperature in the space also rises above the activity start temperature, thereby increasing the activity of pests. In other words, since the timing at which hibernating pests start to become active can be synchronized with the timing at which the amount of transpiration of the pest control agent is increased, when hibernating pests in the space start to become active, the pests can be effectively controlled. [Effects of the Invention]

[0026] As explained above, the amount of pest control agent evaporated into the space can be increased as the room temperature rises, so that pests can be effectively controlled in spaces where they may enter to overwinter. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a perspective view of a warehouse where pests are controlled by a pest control method according to a first embodiment of the present invention. [Figure 2] 1 is a graph showing the relationship between the amount of evaporation of a pest control agent and room temperature. [Figure 3] 1 is a graph showing the mortality rate of pests when metofluthrin is used. [Figure 4] 1 is a graph showing the mortality rate of pests when transfluthrin is used. [Figure 5] FIG. 6 is a cross-sectional view of a warehouse where pests are controlled by a pest control method according to a second embodiment of the present invention. [Figure 6] FIG. 10 is a cross-sectional view of a warehouse where pests are controlled by a pest control method according to a third embodiment of the present invention. [Figure 7] FIG. 10 is a cross-sectional view of a house in which pests are controlled by a pest control method according to a fourth embodiment of the present invention. [Figure 8]FIG. 10 is a perspective view of the bed of a truck in which pests are controlled by a pest control method according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that the following description of the preferred embodiments is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

[0029] (Embodiment 1) FIG. 1 shows a warehouse 1 in which pests are controlled by a pest control method according to a first embodiment of the present invention. In the first embodiment, a case will be described in which pests are controlled within a space R of the warehouse 1 by the pest control method. The warehouse 1 is composed of, for example, a floor 2, side walls 3, and a roof 4. The floor 2 may be made of any material, for example, concrete, wood, or steel plate. The side walls 3 are arranged to surround the floor 2 and extend upward. The material of the side walls 3 is also not important. A roof 4 is installed on top of the side walls 3. The roof 4 may be a ceiling. A space R is defined by the floor 2, side walls 3, and roof 4. The space R according to the first embodiment is a non-residential space where no one lives, and no heating appliances are installed.

[0030] The size, volume, shape, etc. of the warehouse 1 can be set as desired. The warehouse 1 may be fixed to the ground, or may be movable and installed on, for example, a railway vehicle, automobile, airplane, ship, etc. A movable warehouse 1 may be called, for example, a loading platform, a cargo room, a loading room, etc. In either case, it has a space R.

[0031] The room temperature (air temperature within space R) within space R of warehouse 1 fluctuates due to, for example, changes in the outside air temperature and the intensity of solar radiation. The outside air temperature and solar radiation may change depending on the season. For example, the room temperature within space R may fall below 15°C during winter and rise above 20°C from spring to autumn. If warehouse 1 is fixed, the room temperature within space R may rise from below 15°C to above 20°C as the seasons change. Note that, for example, the room temperature within space R of warehouse 1 may fluctuate over the course of a day due to diurnal fluctuations in the outside air temperature. However, it is unlikely that hibernating pests will become active due to such short-term temperature fluctuations alone. Therefore, in the present invention, it may be appropriate to consider the "room temperature" as the average room temperature over a certain period of time. For example, the average room temperature within space R of warehouse 1 over a day may be defined as the "room temperature."

[0032] Furthermore, the outside temperature and solar radiation may vary depending on the region, and the further away from the equator, i.e., the closer to the North and South Poles, the lower the outside temperature and the weaker the solar radiation. Therefore, even if the seasons do not change, if Warehouse 1 is mobile, the room temperature in Space R may rise from below 15°C to above 20°C when it is moved from a high latitude region to a low latitude region.

[0033] Items 5 are stored in space R of warehouse 1. Items 5 are tangible objects other than real estate, and are not particularly limited, but include, for example, household goods, medicines, electrical appliances, books, food, and beverages. These are usually stored in warehouse 1 in a packaged state such as a cardboard box. However, if the items 5 are, for example, furniture, building materials, automobiles, motorcycles, bicycles, etc., they may be stored in warehouse 1 in their original state (exposed) without any special packaging. Note that items 5 do not necessarily have to be stored in space R.

[0034] Warehouse 1 has openings such as entrances and exits for people to enter and exit, and ventilation holes (not shown), through which pests outside warehouse 1 can invade space R. Furthermore, when item 5 is brought into the warehouse, pests attached to item 5 can be brought into space R. This can occur, for example, when item 5 is furniture or the like and pests get into gaps or internal cavities in the furniture while it is temporarily stored outdoors in an unwrapped (exposed) state.

[0035] The pest control method is a method for controlling pests that have been brought into or invaded space R as described above. Control refers to preventing damage caused by pests and eliminating pests to prevent damage before it occurs, including killing the pests. Here, pest damage includes damage to items 5, such as pests soiling or biting items 5. It also includes damage to people, such as pests biting people who enter space R or causing discomfort to people who see pests active in space R. It also includes pests that begin to active in space R and then move outside warehouse 1, causing infectious diseases or agricultural damage to the surrounding area. Therefore, pest damage does not necessarily occur only within space R. Note that if it is sufficient to prevent pest damage only within space R, it is not necessary to kill the pests; for example, pests may be exterminated by driving them out of space R. However, since pest insects are less active during hibernation, they do not cause substantial damage during that period. In this regard, the present invention controls pest insects when they wake up from hibernation and start to become active, thereby effectively preventing pest damage.

[0036] Pests to be controlled by the pest control method are hibernating pests, such as Culex pipiens, flies, moths such as Lymantria dispar and pyralid moths, and stink bugs such as brown marmorated stink bugs, German winged green bugs, and spotted stink bugs. Most of these pests begin hibernation when the temperature drops below 15°C, so 15°C is the hibernation onset temperature. The hibernation onset temperature may vary depending on the pest to be controlled and can be set, for example, within a range of 12°C to 15°C. Furthermore, the temperature at which most hibernating pests begin to become active is 20°C or higher, so 20°C is the activity onset temperature. The activity onset temperature may vary depending on the pest to be controlled and can be set, for example, within a range of 20°C to 25°C. In other words, due to seasonal changes and long-distance migration, the room temperature in space R of warehouse 1 may rise from below the hibernation onset temperature of pests to above the activity onset temperature at which hibernating pests become active. Conversely, it may also fall from above the activity onset temperature to below the hibernation onset temperature.

[0037] In the pest control method, a pest control agent having volatility is used. Here, "volatility" means that the agent is solid or liquid at normal temperature and pressure, and has a vapor pressure that allows it to volatilize gradually. The vapor pressure at 30°C is 1 x 10 -5 ~1×10 -3 A pest control agent with a viscosity of mmHg is suitable for this control method. As the pest control agent, known insecticides can be used, and fragrances having a repellent effect can also be used. Specific examples of the pest control agent include pyrethroid compounds such as transfluthrin, metofluthrin, empenthrin, and profluthrin, with transfluthrin or metofluthrin being preferred. Only one of the pest control agents may be used, or two or more may be mixed or used in combination.

[0038] The pest control method includes a preparation step and a chemical vaporization step as multiple steps. In the preparation step, a holding means for holding a pest control agent is prepared in the space R of the warehouse 1 when the room temperature in the space R is below the hibernation initiation temperature. Examples of the holding means include the inner surface of the floor 2 or the side wall 3. Methods for holding the pest control agent in the holding means include, but are not limited to, spraying using an aerosol container or pump sprayer, applying using a brush or roller, or spraying using a shower container to attach a chemical solution containing the pest control agent to the inner surface of the floor 2 or the side wall 3.

[0039] As an example, a case where an aerosol container 6 is used will be described. This aerosol container 6 contains a pesticide, a solvent for dissolving the pesticide, and a propellant for spraying the pesticide and solvent. Examples of propellants include liquefied petroleum gas (LPG) and dimethyl ether (DME), and any one or more of these can be used alone or in combination. The propellant may contain nitrogen gas or carbon dioxide gas. Furthermore, the aerosol container 6 can be blended with a spreading agent, a volatilization regulator, a synergist, etc., as needed, which allows the efficacy and duration of the pesticide to be adjusted. The aerosol container 6 containing the pesticide can also be called an aerosol product.

[0040] The aerosol container 6 is provided with, for example, a spray nozzle and a spray button (not shown). A user holds the aerosol container 6 in their hand and presses the spray button to spray the pesticide from the spray nozzle. In the preparation process, when the temperature is below the hibernation onset temperature, the pesticide can be sprayed from the aerosol container 6 toward the inner surface of the floor 2 or side wall 3 of the space R, thereby adhering the pesticide to the inner surface of the floor 2 or side wall 3. In this case, the inner surface of the floor 2 or side wall 3 to which the pesticide is attached serves as a holding means. The pesticide may be attached to both the inner surfaces of the floor 2 and the side wall 3, or may be attached only to the floor 2, or may be attached only to the inner surface of the side wall 3. The pesticide may be attached to the entire surface of the floor 2, or only to a portion of the surface. Similarly, the pesticide may be attached to the entire surface of the inner surface of the side wall 3, or only to a portion of the surface. The pesticide may also be attached to the ceiling of the roof 4. In this case, the ceiling serves as the holding means.

[0041] Furthermore, the holding means prepared in the preparation step may be a member that is not fixed to the space R, such as a cloth or plate. In this case, the cloth or plate holding the pest control agent can be installed anywhere within the space R. In this case, the work of attaching the pest control agent to the holding means (cloth, plate, etc.) does not necessarily have to be performed inside the space R; the pest control agent may be attached to the holding means outside the space R, and then the holding means may be brought into the warehouse R. In this way, the holding means holding the pest control agent can be prepared by bringing the holding means into the warehouse R from outside.

[0042] The preparation step may be performed before the items 5 are brought into the warehouse 1, after the items 5 are brought into the warehouse 1, or in parallel with the bringing in of the items 5. However, when the pest control agent is attached to the holding means by spraying, applying, dusting, or the like within the warehouse 1, if there are items 5 nearby, the pest control agent may adhere to the items 5 and cause stains or dirt. From the viewpoint of avoiding this, it is preferable to perform the preparation step before the items 5 are brought into the warehouse 1.

[0043] From the perspective of efficiently evaporating the pest control agent into the space R in the chemical evaporation process described below, it is preferable that the holding means to which the pest control agent is attached in the preparation process be exposed to the space R during the chemical evaporation process. For example, if an item 5 is placed on the floor 2 after the pest control agent has been attached to the floor 2, the portion of the floor 2 in contact with the item 5 will not be exposed to the space R, and the pest control agent attached to that portion will not evaporate efficiently. Therefore, when the preparation process is performed before the item 5 is brought into the warehouse 1, it is preferable not to attach the pest control agent to the portions of the floor 2 or sidewall 3 that will come into contact with the item 5, and it is preferable to attach the pest control agent only to the portions that will not come into contact. Note that a gap of several centimeters between the item 5 and the floor 2 or sidewall 3 holding the pest control agent will not cause any problems with the evaporation of the pest control agent.

[0044] After the preparation step, a chemical transpiration step is carried out. That is, when the pest control agent is held in the holding means in the preparation step, the room temperature in space R is low, below the hibernation onset temperature, so the pest control agent held in the holding means hardly transpires. Thereafter, the room temperature in space R gradually rises with the change of seasons and the movement of warehouse 1. As the room temperature in space R rises, the temperature of the pest control agent held in the holding means rises, thereby increasing the amount of pest control agent transpires into space R from the holding means.

[0045] The effects of the pest control method described above will be explained below.

[0046] That is, when the room temperature in the space R is low enough to be below the hibernation onset temperature, pests hibernate by burrowing into, for example, gaps between items 5 or grooves and cracks in the sidewall 3. Since it is difficult to find pests in this state, it is not realistic to exterminate them one by one. Furthermore, even if the space R were treated with a pest control agent that evaporates at this room temperature, the pests would not be effectively controlled because they are deep in the gaps and their activity is reduced, and the evaporated pest control agent would be wasted.

[0047] In this regard, according to this embodiment, when the room temperature of space R is low, the amount of pest control agent that evaporates from the holding means is less than when the room temperature is high, so when the control effect is low (when pests are hibernating), the amount of pest control agent that evaporates into space R is small, and waste of the pest control agent is reduced.

[0048] Then, as the room temperature in space R rises and exceeds the activity initiation temperature, the hibernating pests begin to become active and crawl out from deep within gaps and the like. Furthermore, as the room temperature in space R rises, the amount of pest control agent evaporating from the holding means increases, increasing the concentration of the pest control agent in the air within space R. In other words, the timing at which hibernating pests begin to become active can be synchronized with the timing at which the amount of pest control agent evaporating can be increased. As a result, when pests hibernating within space R crawl out into space R, the concentration of the pest control agent in the air within space R can be increased, allowing the pests to be effectively controlled.

[0049] Next, the relationship between the transpiration rate of pesticides and temperature will be explained based on the graph shown in Figure 2. This graph shows how the transpiration rates of the pesticides Metofluthrin and Transfluthrin change with temperature. The horizontal axis of the graph represents room temperature (°C), which is approximately the same as the temperature of Metofluthrin and Transfluthrin. The vertical axis of the graph represents the transpiration rate ratio, which is the ratio when the transpiration rate at a room temperature of 25°C is set to 1. For example, a transpiration rate ratio of "2" means that the amount of transpiration is twice the amount at a room temperature of 25°C. The transpiration rates were measured at room temperatures of 35°C, 30°C, 27°C, 25°C, and 22°C. The measurement method involved impregnating a predetermined amount of pesticide into a nonwoven fabric and blowing it with a fan. The air that passed through the nonwoven fabric was then sucked downstream of the nonwoven fabric, and the pesticide contained in the air was collected by silica gel, and the amount collected was measured.

[0050] As can be seen from Figure 2, the transpiration rate of both Metofluthrin and Transfluthrin increases as the room temperature increases, and conversely, decreases as the room temperature decreases. The temperature at which the transpiration rate of Metofluthrin becomes 0 is 18.8°C, calculated by linear approximation, which is below the activity onset temperature mentioned above. The temperature at which the transpiration rate of Transfluthrin becomes 0 is 13.6°C, calculated by linear approximation, which is below the hibernation onset temperature mentioned above, but below the hibernation onset temperature, almost no Transfluthrin transpire.

[0051] As described above, metofluthrin and transfluthrin have moderate transpiration properties above the temperature at which pests are active, and hardly transpire below the temperature at which pests are inactive, particularly below the temperature at which hibernation begins, making them suitable as pest control agents for use in the above-mentioned pest control method. Note that, since the lower the temperature, the lower the transpiration property, and the higher the temperature, the higher the transpiration property, which is a general property of transpiration-prone substances, any pest control agent with a vapor pressure similar to that of metofluthrin or transfluthrin can be used in the pest control method of the present invention.

[0052] (Pest control test) Next, we will explain the test for determining the amount of pesticide required to actually control pests. Male and female brown marmorated stink bugs were prepared as test insects (pests to be controlled). Stink bugs are known to be highly resistant to pesticides (especially pyrethroid-based agents), so if a control agent is effective against stink bugs, it can be expected that it will also be highly effective against other pests such as mosquitoes, flies, and moths.

[0053] The test room is approximately 8 tatami mats (33 m 3) windless, constant temperature chamber. Test insects were placed in plastic cups and covered with a 16-mesh nylon net. The plastic cups containing the test insects were placed on the four corners of the floor of the test room. A fan-type transpiration device for transpiration of the pesticide (Metofluthrin) was installed in the center of the floor of the test room. The room temperature during the test was 25°C, and the test room was kept sealed without ventilation. During the test, the test insects were fed soybeans and water, and the condition of the test insects was observed for one week from the start of the test. The amount of Metofluthrin transpiration was 2.5 mg per hour (Test Example 1) and 5.0 mg per hour (Test Example 2).

[0054] As shown in Figure 3, after 4 days from the start of the test, the mortality rate exceeded 50% in both Test Examples 1 and 2, demonstrating that the control effect of Metofluthrin is sufficiently high. In particular, it can be seen that after 7 days at an evaporation rate of 5.0 mg / hr (Test Example 2), the mortality rate can be increased to 100%.

[0055] Based on the above, the minimum amount of Metofluthrin required to completely eliminate stink bugs is: 5.0mg / hr × 168hr (7 days) / 33m 3 = 25 mg / m 3 It is estimated that the amount of Metofluthrin required to completely eliminate stink bugs can be calculated by knowing the volume of the space R in which the pest control method is used. By holding at least this amount of Metofluthrin in a holding means and placing it in space R, it is possible to eliminate stink bugs when the room temperature in space R reaches or exceeds the activity initiation temperature and hibernating stink bugs begin to become active. Note that if the goal is not to completely eliminate stink bugs, for example, if it is sufficient to simply expel stink bugs from space R, the amount of Metofluthrin used can be less than the amount described above.

[0056] If another pesticide is used instead of metofluthrin, or if multiple pesticides are used in combination, the minimum amount of pesticide required to control stink bugs within space R can be calculated by conducting similar tests.

[0057] Next, a test will be described in which an aerosol container 6 containing transfluthrin as a pest control agent was used to confirm the stink bug control effect using the floor of a test room as a holding means.

[0058] The test room and test insects were the same as when the above-mentioned evaporation device was used. Note that because transfluthrin has a vapor pressure approximately twice that of metofluthrin, it is evaporated and consumed quickly, so twice the amount of metofluthrin (50 mg / m) was used. 3 ) of transfluthrin would be enough to eradicate 100% of the stink bugs. 3 The required amount of transfluthrin (50 mg / m) predicted from the volume of 3 ×33m 3 A total of 1.65 g of insecticides (1.65 g) was placed in an aerosol container 6. The entire contents of this aerosol container 6 was sprayed onto the floor of the test room to adhere it to the floor. The test insects were then placed in a plastic cup covered with a 16-mesh nylon net and placed in the test room. The room temperature during the test was 25°C, and the ventilation conditions were set to either no ventilation or six ventilations per hour.

[0059] The mortality rates of the test insects were calculated on the day the test began, and four and six days after the start of the test. The results are shown in the graph in Figure 4. In other words, without ventilation, the mortality rate was 100% on the day the test began, and with ventilation six times per hour, the mortality rate was 90% on the day the test began. This shows that by retaining the calculated required amount of pesticide (transfluthrin in this case) in the holding means (on the floor in this case), sufficient control effect against stink bugs active in the space can be achieved. Note that, because the effectiveness decreases when ventilation is performed, it is preferable to increase the amount of pesticide retained in the holding means beyond the amount mentioned above depending on the ventilation conditions.

[0060] Furthermore, as mentioned above, stink bugs are pests that are resistant to pesticides, so if a pesticide is effective against stink bugs, it will also be sufficiently effective against mosquitoes, flies, moths, and the like. For example, research by the present inventors has shown that a pesticide that is about 1 / 170 of the amount required for a pesticide to be effective against house mosquitoes, about 1 / 19 of the amount required for a pesticide to be effective against stink bugs, and about 1 / 4.5 of the amount required for a pesticide to be effective against stink bugs and gypsy moths. Therefore, if a pesticide is not targeted at stink bugs and only relatively weak pests such as mosquitoes, flies, or moths are targeted, the amount of pesticide can be reduced accordingly.

[0061] (Embodiment 2) 5 is a cross-sectional view of a warehouse 1 in which pests are controlled by a pest control method according to a second embodiment of the present invention. The second embodiment differs from the first embodiment in that the pest control agent is diffused into the space R by using the outside air taken in from outside. Hereinafter, the same parts as those in the first embodiment will be assigned the same reference numerals and their explanation will be omitted, and the different parts will be described in detail.

[0062] An outside air intake duct 11 is provided on the side wall 3 of the warehouse 1. The outside air intake duct 10 is installed so as to penetrate the side wall 3 in the thickness direction. An outside air intake hole 10a is formed within the outside air intake duct 10 to bring air from outside the warehouse 1 (outside air) into the warehouse 1. The upstream end opening of the outside air intake hole 10a faces the outside of the warehouse 1, while the downstream end opening of the outside air intake hole 10a faces the inside of the warehouse 1. A fan 11 and a motor 12 that drives the fan 11 are disposed within the outside air intake duct 10. A power circuit (not shown) is connected to the motor 12, allowing the motor 12 to be started and stopped at the desired timing and to rotate at the desired rotation speed. Although not shown, the warehouse 1 is also provided with an exhaust vent that opens appropriately when introducing outside air to ensure unhindered introduction of outside air. The pesticide may be impregnated into the impregnated body 13 in advance, taking into account the amount of pesticide that will be discharged from the exhaust port.

[0063] An impregnated body 13 impregnated with the pest control agent used in embodiment 1 is disposed downstream within the outside air intake hole 10a. The impregnated body 13 can be made of a breathable material such as a nonwoven fabric, a foam material, or a mesh material, and may be flat or pleated. By disposing the impregnated body 13 downstream within the outside air intake hole 10a, the impregnated body 13 can be installed so that it is exposed to the outside air taken in through the outside air intake hole 10a. Either the fan 11 or the impregnated body 13 may be disposed upstream in the air flow direction, and the impregnated body 13 may be disposed upstream of the fan 11 in the air flow direction.

[0064] The impregnated body 13 can be replaced with a new one. For example, if the impregnated body 13 is incorporated into a chemical cartridge, when the amount of impregnated pest control agent becomes low, the old chemical cartridge is replaced with a new chemical cartridge. The amount of impregnated pest control agent can be estimated based on the operating time of the fan 11.

[0065] In the preparation process of embodiment 2, when the room temperature inside space R and the temperature outside space R are below the hibernation onset temperature, the impregnated body 13 impregnated with a pest control agent is placed so that it is exposed to outside air taken in through the outside air intake holes 10a. Because the room temperature inside space R is below the hibernation onset temperature, the pests inside space R are in a hibernation state. Furthermore, because the temperature outside space R is below the hibernation onset temperature, even if outside air is introduced through the outside air intake holes 10a, the room temperature inside space R remains below the hibernation onset temperature. Furthermore, because the outside air below the hibernation onset temperature hits the impregnated body 13, the pest control agent hardly transpires.

[0066] In the subsequent chemical vaporization process, outside air is introduced through the outside air intake hole 10a. When the temperature outside the space R rises due to seasonal changes or the movement of the warehouse 1, outside air at or above the activity initiation temperature hits the impregnated body 13. This causes the temperature of the pest control agent impregnated in the impregnated body 13 to rise above the activity initiation temperature, thereby increasing the amount of pest control agent vaporized from the impregnated body 13 into the space R. Furthermore, by introducing outside air at or above the activity initiation temperature, the room temperature in the space R rises above the activity initiation temperature, causing pests to begin to become active. Therefore, in the case of embodiment 2 as well, the timing at which hibernating pests begin to become active can be synchronized with the timing at which the amount of vaporization of the pest control agent is increased, thereby enabling effective control of pests when they begin to become active in the space R.

[0067] The introduction of outside air through the outside air intake hole 10a may be performed continuously or only during the chemical vaporization process. When the introduction of outside air through the outside air intake hole 10a is performed continuously (i.e., when the fan 11 is constantly driven, even during winter), the impregnated body 13 is constantly exposed to airflow, which may result in some evaporation of the pesticide from the impregnated body 13 even during winter. Even in this case, if the outside air temperature is below the hibernation start temperature, the amount of evaporation of the pesticide is suppressed, thereby preventing unnecessary evaporation of the pesticide. However, to further prevent unnecessary evaporation of the pesticide, it is preferable to introduce outside air only during the chemical vaporization process (i.e., not driving the fan 11 during winter). A single warehouse 1 may have multiple outside air intake holes 10a and impregnated bodies 13. The outside air intake holes 10a and impregnated bodies 13 may also be installed on the ceiling. Furthermore, the holding means of the first embodiment and the impregnated body 13 of the second embodiment may be used in combination.

[0068] (Embodiment 3) 6 is a cross-sectional view of a warehouse 1 in which pests are controlled by a pest control method according to a third embodiment of the present invention. The second embodiment differs from the first embodiment in that a heating device 20 is installed. Hereinafter, the same parts as those in the first embodiment will be assigned the same reference numerals and their explanations will be omitted, and the different parts will be described in detail.

[0069] A heating device 20 is installed in the warehouse 1 to heat the air in the space R. The heating device 20 may be, for example, a stove, an electric heater, a heat pump air conditioner, or the like, and its type is not particularly limited. The heating device 20 may also be installed outside the warehouse 1. In this case, a duct can be provided to introduce the warm air sent from the heating device 20 into the space R. In winter, when the heating device 20 is turned off, the room temperature in the space R falls below the hibernation starting temperature. At this time, a preparation process is carried out to retain the pest control agent on, for example, the floor 2 or the inner surface of the side wall 3.

[0070] Since no one lives in the warehouse 1, the heating device 20 is usually kept off. Therefore, almost no pest control agent evaporates until the season changes to spring. However, if it is discovered that pests are likely to have entered the warehouse 1 and are hibernating, or if it becomes necessary to exterminate pests during the winter for some reason, the heating device 20 is activated to forcibly raise the temperature inside the warehouse 1 to above the temperature at which pests start to become active. This causes the pests to crawl out and increases the amount of evaporation of the pest control agent, thereby controlling the pests. Therefore, in the case of the third embodiment, the timing at which hibernating pests start to become active and the timing at which the amount of evaporation of the pest control agent is increased can be synchronized, so that when hibernating pests start to become active in the space R, the pests can be effectively controlled. In addition to the heating device 20 of the third embodiment, the impregnated body 13 of the second embodiment may be installed.

[0071] (Embodiment 4) 7 is a cross-sectional view of a house 30 in which pests are controlled by a pest control method according to a fourth embodiment of the present invention. The fourth embodiment differs from the first embodiment in that the present invention is applied to a house 30 inhabited by people. The differences from the first embodiment will be described in detail below.

[0072] The house 30 is, for example, a vacation home or the like that is uninhabited during the winter and inhabited only from spring to autumn. The house 30 has a floor 32, side walls 33, and a roof 34 that divide an interior space R1. Furniture 35A, electrical appliances 35B, and other items are placed in the interior space R1, and pests may get into the gaps or inside these items and hibernate, but they do not come out during the winter.

[0073] In the fourth embodiment, at the beginning of winter, the pest control agent stored in the aerosol container 6 is applied to the floor 32, the inner surface of the side wall 33, and the like. As the season changes to spring and the outdoor temperature rises, pests begin to become active when the temperature in the indoor space R1 rises above the activity start temperature. When the pests begin to become active, the amount of evaporation of the pest control agent increases, allowing the pests to be controlled. Therefore, when the warm season arrives and people move into the house 30, the pests have already been controlled, preventing pest damage.

[0074] (Embodiment 5) Fig. 8 is a perspective view of a truck bed 40 that controls pests using a pest control method according to a fifth embodiment of the present invention. The fifth embodiment differs from the first embodiment in that the present invention is applied to the truck bed 40. The differences from the first embodiment will be described in detail below. The vehicle body is omitted from Fig. 8.

[0075] 8 is a perspective view of a truck bed 40 seen from the rear of the vehicle; this truck is a long-distance truck. Bed 40 has a cargo compartment (space) R2 defined by a floor 42, side walls 43, and an upper wall 44. Cargo compartment R2 can be opened and closed by a door 46. Note that the present invention can also be applied to a container on a freight train or the cargo compartment of a long-distance transport ship, instead of a long-distance truck.

[0076] For example, a long-distance truck travels from a cold region where the outside temperature is below 15°C (hibernation temperature) to a warm region where the outside temperature is above 20°C (activity temperature). The temperature inside the cargo compartment R2 of such a long-distance truck changes in the same way as the outside temperature, rising from below the hibernation temperature to above the activity temperature. When the temperature inside the cargo compartment R2 is below the hibernation temperature, a pest control agent is stored on the floor 42, the inner surface of the side wall 43, the inner surface of the upper wall 44, etc. of the cargo compartment R2. There is a risk of pests hibernating inside the cargo compartment R2 when the temperature is below the hibernation temperature, but when the truck travels to a warmer region, the pests crawl out and the evaporation rate of the pest control agent increases, allowing the pests to be controlled, thereby preventing pest damage to cargo, etc.

[0077] Furthermore, in the fifth embodiment, an outside air intake hole 49 may be provided as in the second embodiment, and an impregnated body 48 impregnated with a pest control agent may be installed. In this case, when the room temperature inside the luggage compartment R2 and the temperature outside the luggage compartment R2 are below the hibernation start temperature, the impregnated body 48 is installed so that it is exposed to outside air taken in through the outside air intake hole 49 provided in the side wall portion 43.

[0078] Thereafter, outside air is taken in through the outside air intake holes 49, and the amount of pest control agent transpire into the cargo compartment R2 from the impregnated body 48 increases as the temperature outside the cargo compartment R2 rises. When room temperature R2 reaches or exceeds the temperature at which pests begin to become active, pests that have begun to become active can be controlled.

[0079] The above-described embodiment is merely illustrative in all respects and should not be interpreted as limiting. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention. For example, the present invention can be applied to attics, stores that are not used during the winter, garages, etc. [Industrial Applicability]

[0080] As described above, the pest control method according to the present invention can be used in spaces into which pests may enter to overwinter, for example. [Explanation of symbols]

[0081] 1 warehouse 2 Floor (holding means) 3 Side wall (holding means) 6. Aerosol containers 10a Outside air intake 13 Impregnated body R space

Claims

1. A pest control method for controlling pests in a space, comprising: When the room temperature inside the space and the temperature outside the space are equal to or lower than the hibernation initiation temperature at which the pests to be controlled start hibernation, an impregnated body impregnated with a transpiration-type pest control agent is placed so that it is exposed to outside air taken in through an outside air intake hole provided in a wall section that partitions the space, Then, outside air is taken in through the outside air intake hole, and the amount of pest control agent evaporated from the impregnated body into the space is increased by increasing the temperature outside the space, and the pests that have begun to become active when the room temperature reaches or exceeds the temperature at which the hibernating pests begin to become active are controlled in this pest control method.

2. The pest control method according to claim 1, Vapor pressure at 30°C is 1 x 10 -５ ~1 x 10 -３ A method for controlling pests, comprising retaining the pest control agent at a resistance of mmHg in the impregnated body.

3. The pest control method according to claim 2, The pest control method, wherein the pest control agent is at least one of transfluthrin and metofluthrin.

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