JP3114321B2 - Flying dipteran hygiene pest control agent - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flying dipteran hygiene pest control agent.

[0002]

2. Description of the Prior Art Conventionally, in indoor residual spraying such as control of flying dipteran hygiene pests, particularly malaria mosquito control, organic chlorine such as DDT is used. Compounds and organophosphorus compounds have been used. However, in the case of organochlorine compounds, there is a problem of persistence in the environment, and in the case of organophosphorus compounds, there is a problem that the insecticidal effect is lost in a short period of time. Development of a mold is desired.

[0003]

In view of such a situation,
The present inventors have conducted intensive studies to find a control agent having a high residual effect on flying dipteran hygiene pests such as flies and mosquitoes. As a result, the organophosphorus insecticide was micro-coated with a polyurethane-based or polyurea-based coating. Encapsulation, at which time the average particle size of the microcapsules is 1 to 40 μm
Further, it has been found that the residual effect is particularly improved when the film thickness is controlled to be 0.01 μm to 0.08 μm and (average particle diameter / film thickness) is 400 to 1000, and the present invention has been completed. That is, the present invention provides a polyurethane-based film or a polyurea-based film having an average particle size of 1 to 40 μm, a film thickness of 0.01 to 0.08 μm, and a (average particle size / film thickness) ratio of 400 to 1000. Provided is a microencapsulated flying dipteran hygiene pest control agent (hereinafter referred to as the control agent of the present invention), which contains an organophosphorus insecticide compound in a coating film. Among the control agents of the present invention, those having an average particle size of the microcapsules of 5 to 30 μm are particularly preferable from the viewpoint of insecticidal efficacy.

In the control agent of the present invention, microencapsulation is carried out, for example, by dispersing a hydrophobic solution containing a polyfunctional isocyanate and an organophosphorus insecticide compound in an aqueous solution containing a water-soluble polymer as a suspending and dispersing agent. After suspending in the form of droplets, the reaction can be carried out by causing a polymerization reaction with water or a polyhydric alcohol having two or more hydroxyl groups. Then, after the microencapsulation reaction, the obtained microcapsule dispersion is diluted with pure water so as to have a predetermined concentration, and a dispersion stabilizer is added if necessary.
The pesticidal composition of the present invention can be produced as a stable slurry-type preparation. Examples of the water-soluble polymer as a suspending / dispersing agent include natural polysaccharides such as gum arabic, semi-synthetic polysaccharides such as carboxymethylcellulose and methylcellulose, synthetic polymers such as polyvinyl alcohol, and fine powders of minerals such as magnesium and aluminum silicate. Are used alone or in combination of two or more. When the suspension dispersibility is weak, the suspension dispersibility can be improved by adding a known surfactant described in "Synthetic surfactant" written by Hiroshi Horiguchi (published by Sankyo Publishing Co., Ltd., 1972). Can be better. Examples of the polyfunctional isocyanate include toluene diisocyanate, hexamethylene diisocyanate, an adduct of toluene diisocyanate with trimethylolpropane, a self-condensate of hexamethylene diisocyanate, Sumidur L (manufactured by Sumitomo Bayer Urethane Co., Ltd.), and Sumidur N (Manufactured by Sumitomo Bayer Urethane Co., Ltd.). Organophosphorus insecticide compounds include fenitrothion, cyanophos, salithione, phoxime, chlorpyrifos, chlorpyrifos-methyl, propetamfos, pyridafenthion, isofenfos,
Examples thereof include thiophos, dimethoate, malathion, fenthion, and diazinon, and of course, a mixture with another insecticide can be used. The content of these active ingredients is usually 1 to 1 with respect to the total weight of the pesticidal composition of the present invention.
It is 50% by weight, preferably 2 to 40% by weight. If necessary, BHT (2,6-di-
A stabilizer such as tert-butyl-4-methylphenol), an antifreezing agent, a preservative and the like can also be added. As the composition of the hydrophobic solution, a mixture of the polyfunctional isocyanate and the organophosphorus pesticide can be used directly when the two are dissolved, but when they are not mutually soluble, they are mixed with water. It is desirable to select a material capable of dissolving the polyfunctional isocyanate and the organophosphorus insecticide compound in a difficult organic solvent, and use a homogeneous mixture of the three (polyfunctional isocyanate, organophosphorus insecticide compound, solvent). Organic solvents used for this purpose include, for example, hydrocarbons such as xylene, toluene, alkylbenzene, hexane and heptane, chlorinated hydrocarbons such as chloroform, ketones such as methyl ethyl ketone and cyclohexanone, diethyl phthalate, n-butyl acetate and the like. And the like. Examples of the polyhydric alcohol having two or more hydroxyl groups include ethylene glycol, propylene glycol, butylene glycol, hexanediol, heptanediol, dipropylene glycol, triethylene glycol, glycerin, resorcinol, hydroquinone, and the like. As the dispersion stabilizer of the microcapsule slurry, the water-soluble polymer as the above-mentioned suspension dispersant can be used as it is, but if necessary, natural polysaccharides such as xanthan gum and locust bean gum, carboxymethylcellulose Or a mixture of two or more semi-synthetic polysaccharides, synthetic polymers such as sodium polyacrylate, and mineral fine powders such as magnesium-aluminum silicate may be used as a thickener. The amount added
Usually, it is in the range of 0.1 to 20% by weight.

[0005] The average particle size of the microcapsules is determined by the type and concentration of the water-soluble polymer used as the suspending and dispersing agent and the strength of mechanical stirring during suspension and dispersion. For the measurement of the average particle size, for example, a Coulter counter model TA-II type (manufactured by Nikkaki Co., Ltd.) can be used. The film thickness of the microcapsules changes depending on the volume ratio between the core material and the film material, and can be determined by an approximate expression such as Equation 1. That is, assuming that the weight of the core material of the microcapsule is Wc, the weight of the membrane material is W _w , the density of the membrane material is ρ _w , the density of the core material is ρ _c , and the average particle size of the core material is d.

(Equation 1) Becomes The film thickness referred to in the present invention is a value calculated using this formula.

[0006] The control agent of the present invention is a flying dipteran hygiene pest,
That is, flies such as house flies, house flies, and pine trees, mosquitoes such as Culex pipiens, chikaeka, Aedes albopictus, and mosquitoes such as Aedes albopictus, blackflies such as blue foxtail flies, butterfly flies such as fly flies, and flyfishes such as smeltfishes and glypts, etc. It is effective for such as. When the control agent of the present invention is used as a control agent for flying dipteran hygiene pests, the amount of application depends on the type of pest, but the amount of the active ingredient is 10 mg / m ² to 2000.
It is preferable to spray a water diluent so as to be mg / m ² . Further, the application amount of the water diluent is preferably 10 ml / m ^{2 to} 100 ml / m ² .

[0007]

EXAMPLES The present invention will be described in more detail with reference to Production Examples and Test Examples, but the present invention is not limited thereto. Production Example 1 3.5 g of Sumidur L (same as above) was added to 200 g of fenitrothion and stirred until a homogeneous solution was obtained. This was mixed with an aqueous solution containing 5% by weight of gum arabic as a suspending and dispersing agent.
0 g and T.P. K. Using an auto homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.)
Stirred for a few minutes. The number of revolutions was 5000 rpm. Then
After dropping 6 g of ethylene glycol into the reaction system,
The reaction was carried out for 24 hours with gentle stirring in a constant-temperature water bath at ℃ to obtain a dispersion of microencapsulated material. To this was added 300 g of a thickener aqueous solution containing 2.0 g of xanthan gum and 4.0 g of magnesium-aluminum silicate, and further adjusted to 1000 g by adding ion-exchanged water, and the content of the active ingredient was 20% by weight of fenitrothion. A microcapsule slurry was obtained. The average particle size of the obtained microcapsules was 20.3 μm, the film thickness was 0.050 μm, and the ratio (average particle size / film thickness) was 406. Production Example 2 The same operation as in Production Example 1 was carried out except that ethylene glycol was not added, to obtain a fenitrothion microcapsule slurry having an active ingredient content of 20% by weight. The average particle size of the obtained microcapsules is 20.9 μm, and the film thickness is 0.047 μ.
m, the ratio of (average particle diameter / film thickness) was 445. Production Example 3 The same operation as in Production Example 1 was carried out except that the amount of Sumidule L (same as above) was changed to 2.5 g, to obtain a fenitrothion microcapsule slurry having an active ingredient content of 20% by weight. The average particle size of the obtained microcapsules is 19.9 μm,
The film thickness was 0.035 μm, and the ratio (average particle diameter / film thickness) was 569. Production Example 4 The same operation as in Production Example 1 was carried out except that the amount of Sumidur L (same as above) was 2.5 g, and ethylene glycol was not added, to obtain a fenitrothion microcapsule slurry having an active ingredient content of 20% by weight. Was. The average particle size of the obtained microcapsules was 19.5 μm, the film thickness was 0.031 μm, and the ratio (average particle size / film thickness) was 629. Comparative Example 1 The same operation as in Production Example 1 was performed except that the amount of Sumidule L (the same as described above) was changed to 11.0 g, to obtain a fenitrothion microcapsule slurry having an active ingredient content of 20% by weight. The average particle size of the obtained microcapsules is 20.5 μm,
The film thickness was 0.158 μm, and the ratio (average particle size / film thickness) was 130. Comparative Example 2 The same operation as in Production Example 1 was carried out except that the amount of Sumidur L (same as above) was changed to 1.0 g and ethylene glycol was not added, to obtain a fenitrothion microcapsule slurry having an active ingredient content of 20% by weight. Was. The average particle size of the obtained microcapsules was 21.3 μm, the film thickness was 0.014 μm, and the ratio (average particle size / film thickness) was 1521. Test Example 1 An active ingredient of 1 g / m ² was placed on a 15 x 15 cm unglazed plate (absorbent plate)
The water dilution of each sample was sprayed from a distance of 60 cm with a spray gun so that After air-drying, 10 adult female Culex pipiens were tested on a predetermined day, covered with a petri dish having a height of about 1 cm, and forcedly contacted with the treated surface for 2 hours. After 2 hours, the test insects were collected in a plastic cup, fed, and the mortality one day later was determined. Using the same treated surface, the same operation was performed at intervals of 2 to 3 weeks, and the residual effect was examined. (3 repetitions) The results are shown in Table 1.

[Table 1]

[0008]

The control agent of the present invention has excellent insecticidal activity against flying dipteran hygiene pests.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takaaki Ito 4-2-1 Takashi, Takarazuka-shi, Hyogo Sumitomo Chemical Industries Co., Ltd. (72) Inventor Shigenori Tsuda 4-2-1 Takashi, Takarazuka-shi, Hyogo Sumitomo (56) References JP-A-64-13003 (JP, A) JP-A-62-215504 (JP, A) JP-A-53-149179 (JP, A) JP-A-62-67003 ( JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) A01N 57/00 A01N 25/28 A01N 25/12 101

Claims (1)

(57) [Claims] (1) An average particle size is 1 to 40 μm and a film thickness is 0.1 μm.
A microcapsule characterized in that an organophosphorus insecticide compound is encapsulated in a polyurethane-based coating or a polyurea-based coating having a ratio of (average particle diameter / film thickness) of from 0.01 to 0.08 μm and (average particle diameter / film thickness) of from 400 to 1000. Flying Diptera sanitary pest control agent