JPH0219081B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an appropriate termite prevention and control method for preventing or controlling termites that damage the wooden parts of houses. (Prior Art) Conventionally, methods for preventing and controlling termite damage to wooden parts such as flooring and pillars of houses include brushing, spraying, or foaming with termite control agents in the form of oil or emulsion. Termite control agents in the form of emulsions or granules have been applied to the soil, which is the habitat and passageway for termites, by spraying, foaming, scattering, etc. However, in order to achieve the desired control effect using this method, a large amount of termite control agent is required, and usually an amount of about 50 to 100 g of the active ingredient is applied per 1 m ² of soil surface. There is a risk of environmental pollution when such large amounts of chemicals are used, and recently, as a countermeasure, a method has been used in which termite control agents are contained in sheet-like carriers and spread on the soil surface under floors, foundations, etc. (Problem to be solved by the invention) However, with the method of laying sheets, it is difficult to work because it requires work in narrow spaces such as under the floor.
In addition, the work is complicated because the sheet must be cut to match the shape of the irregularly shaped subfloor or foundation, and there is a gap between the sheet and the foundation, making it difficult to obtain a complete termite prevention effect. It was hot. Another method is to spray a synthetic resin emulsion containing the chemical, but this method causes the emulsion to be absorbed into the soil before a dry synthetic resin film is formed on the soil surface, resulting in a large loss of chemical solution. However, there is also a drawback that it is difficult to obtain a homogeneous film due to the unevenness of the soil surface, and improvement of this problem has been desired. (Means for Solving the Problems) As a result of various studies conducted by the present inventors in order to eliminate the drawbacks of the conventional termite control methods as described above, the present inventors first applied a termite control agent of 50 g/m ² or more. We have discovered a method of uniformly spreading soil mixed with a termiticide in a thickness of 1 cm or more (Japanese Patent Application No. 35556/1983). The technology of this prior application had some issues in terms of work efficiency and occupational health for workers, so as a result of further research, we found that:
Found a method for forming a termite-controlling layer with a certain thickness or more on the surface layer of the soil by spraying a urethane prepolymer containing a termite-controlling agent onto soil moistened with water, causing the foam to penetrate and harden into the soil. Ta. The present invention was completed based on these new findings, and involves spraying a urethane prepolymer containing 0.5% or more of a termite control agent onto soil moistened with water.
The urethane prepolymer containing a termite control agent foams with water and penetrates into the soil, covering 1 to 2 cm of the surface of the soil as a hardened layer of foamed polyurethane, thereby preventing and controlling termites from feeding on the wooden parts of houses. The present invention provides a method. In the present invention, 0.5% by weight or more of a termite control agent is added, dissolved or suspended in the urethane prepolymer, and the termite control agent to be added is, for example, an organic chlorine compound such as chlordane, an organic phosphorus compound such as chlorpyrifos, or phoxim. Compounds, other antermicidal compounds that are relatively stable in the clay pot, such as boron, boron compounds such as borax, and dehydroacetic acid, can be used as appropriate. Urethane prepolymer can be used as is, but due to its high viscosity, paint thinner,
Alternatively, it may be diluted appropriately at any ratio up to 2 times dilution using an organic chlorine solvent, etc., and then sprayed. Before spraying the urethane prepolymer containing the termite control agent onto the surface of the soil using a sprayer, it is preferable to moisten the surface of the soil with water. The appropriate amount of water to be sprayed is in a ratio of 9:1 to 2:8, preferably 4:1 to 2:3 to the urethane prepolymer. In a dry state with a small amount of water sprayed, the urethane prepolymer does not fit well with the soil, making it difficult to harden it uniformly. The amount of urethane prepolymer treated per unit area of the soil surface is 1.5 to 2.0 Kg/ ^m2 , and the amount is 1 to 2 cm from the soil surface.
Polyurethane containing 0.5% termite control agent foamed with water penetrates and fills, forming a hardened layer. (Function) The termite prevention and control method of the present invention has the following advantages. That is, the isocyanate group of the urethane prepolymer reacts with water to form a urea bond, forming a strong urethane resin layer in the pot, so that termite prevention and control effects can be sustained over a long period of time. (b) In sheets containing termite control agents, if there is sand and gravel on the surface of the soil, gaps will be created, and gaps will also be created between the soil and the foundation, but according to the method of the present invention, the foam will penetrate and penetrate into the gaps between the soil and gravel. Fill. Therefore, the killing rate of underground termites is high, and the number of termites that penetrate the urethane resin layer and come out to the surface is small. C. The work is extremely easy as all you have to do is sprinkle water on the ground and then spray the urethane prepolymer with a sprayer.
In addition, worker safety is ensured in terms of occupational health. D. The drug dose is 7.5g ^per square meter of soil surface, which is effective.
The amount of chemicals required is less than 1/6 of the conventional method. (e) In addition to the low drug dose, the drug is solidified with a urethane resin layer, so there is no runoff of the drug, and environmental pollution can be prevented. Since the urethane resin layer blocks moisture, it has a moisture-proofing effect on houses. (Example) Examples of the termite prevention and control method of the present invention will be described below. Note that the present invention is not limited to the following examples. Example 1: Mix chlordane, a termite control agent, with urethane prepolymer, treat the surface of the soil to form a urethane resin layer, and check whether termites penetrate the urethane resin layer or not. A prevention and control effect test was conducted to determine whether the termites that appeared on the tree would damage the tree (penetration test). Test method: Spread 50 g of mountain soil to a uniform thickness on the bottom of a polyvinyl chloride vat (20 x 13 x 9 cm), and place a vinyl chloride cylinder (diameter 7 cm) on top of the soil in the center of the vat.
cm, height 12cm). Place 210g of potting soil (moisture content 20%) in this cylinder to a depth of 6cm.
to level the surface, and then spray 3 ml of water onto the surface of the potting soil to wet it. After that, 5.7 g of urethane prepolymer containing chlordane (1.5 Kg/m ²
(equivalent) was added dropwise evenly over the entire surface of the potting soil with a pipette and left for 3 days to form a urethane resin layer. A test piece of wood is placed on the urethane resin layer, and the termites released into the vat sneak under the cylinder, and after penetrating the urethane resin layer, the number of surviving termites and the degree of damage to the test piece of wood are determined. For comparison, an untreated area with only potting soil inside the cylinder was set up and investigated in the same manner. Test conditions: Test termite control agent Chlordane base Test soil Plant soil (20% moisture content) Test wood piece Pine (10 x 10 x 20 mm)

【table】

【table】 Test results:

[Table] Results: 1. In the 0.5% chlordane addition areas No. 2 and No. 5, punctures by termites were observed in the urethane resin layer, but the termites that appeared on the urethane resin layer were in a state of knockdown and caused damage to the wood chips. They die without doing anything. It is found to be effective in preventing wood chip damage. Furthermore, all of the termites living in the soil beneath the urethane resin layer are killed before they emerge to the surface, demonstrating sufficient termite control power. 2. In plots No. 3 and No. 6 containing 1% chlordane, there were no termites that came out on the urethane resin layer, and all of them died in the soil. Example 2: The preventive and control effects against termites were tested in the same manner as in Example 1 except that the termite control agent was changed from chlordane to phoxim. Test method: Same as Example 1. However, chlordane was replaced with phoxim. Test conditions: Test termite control agent Basilium-I-Conc 441
(Phoxim concentration 64.5%) Test soil Plant soil (moisture content 20%) Test piece of wood Pine (10 x 10 x 20 mm) Test termites Domestic termites 1 area 2 series Worker ants 300 soldiers 30 soldiers

【table】 Test results:

【table】

[Table] Results: 1 Phoxim 0.5% addition group No. 8 and No. 11 and 1
In both No. 9 and No. 12, all of the termites died in the soil without coming out onto the urethane resin layer, indicating that the termite control power was sufficient. Example 3: 0.5% termite control agent was added to and mixed with urethane prepolymer, and the formed urethane resin layer was brought into contact with termites to examine the presence or absence of termite killing effect (contact test). Test method: Put 10 g of potting soil into a 9 cm diameter shear dish, level it evenly, spray 5 ml of water on the surface of the potting soil to moisten it, and mix 0.5% termite control agent with 9.4 g (1.5 g) of urethane prepolymer. (equivalent to Kg/ ^m2 ) evenly over the entire surface with a pipette. After leaving it for 3 days to fully form a urethane resin layer, 20 worker termites per shear were released on the surface, and the number of dead insects over time was examined. Test conditions: Termite control agent tested Chlordane active substance, Basillium-I-Conc 441, sumithion active substance, chlorpyrifos active substance Test soil Plant soil (water content 20%) Test termite Household termite 1 area Double system Worker ants 20 Head

【table】

【table】 Test results:

[Table] (Effects of the Invention) As mentioned above, according to the method of the present invention, termites can kill any drug after 5 hours if the active ingredient is in the urethane resin layer with a dose of 7.5 g/ ^m2 . More than 70% of the insects lose their ability to act, and all of them die within a day, making the pesticidal effect extremely effective. Moreover, the fact that there are no eating marks on the urethane resin layer indicates that the pesticidal effect is exerted just by contact.

Claims (1)

[Claims] 1. A method for preventing and controlling termites, which comprises treating and curing the surface layer of soil containing moisture with a water-reactive curable urethane prepolymer containing a termite control agent to form a urethane resin layer.