JPH06247811A - Insecticidal composition - Google Patents

Abstract

PURPOSE:To obtain an insecticidal composition maintaining the insecticidal effect over a long period, especially effective for controlling wood injurious insects, etc., and reduced in toxicity. CONSTITUTION:A microcapsuled insecticidal composition comprising a carbamate insecticidal compound such as fenobucarb, propoxur, xylylcarb, metolcarb, isoprocarb or metoxadiazone capsuled with coating films having an average particle diameter of 5-80mum and an average particle diameter/film thickness of <200, and suitable for controlling wood injurious insects.

Description

Detailed Description of the Invention

[0001]

This invention relates to insecticidal compositions. More particularly, it relates to an insecticidal composition suitable for controlling wood pests.

2. Description of the Related Art Conventionally, various insecticidal compositions for controlling wood pests are known, but they are inexpensive and have a long-term residual effect in controlling wood pests. In addition, there is a need for compounds that do not have problems due to residual toxicity, such as organochlorine insecticides that have been used extensively in the past, and the development of effective insecticidal compositions that satisfy these conditions is desired. Was there.

[0002]

[Means for Solving the Problems] Carbamate insecticidal compounds are generally inexpensive, but when used for controlling wood pests such as termites and flat beetles, they impart a long-term residual effect and are a problem due to residual toxicity. It is necessary to devise so that there is not. In the present invention, the average particle size is 5 to 80 μm, preferably 10 to 80 μm, and the (average particle size / film thickness) value is 20.
The present invention provides a microencapsulated insecticidal composition (hereinafter referred to as the composition of the present invention) in which a carbamate insecticidal compound is included in a coating film having a coating amount of less than 0, preferably less than 100. The composition is particularly suitable for controlling wood pests.

The carbamate insecticidal compound used in the present invention is not particularly limited, but examples thereof include the compounds shown below. Fenobucarb; 2-Secondary butylphenyl N
-Methylcarbamate propoxur; 2-isopropoxyphenyl N-methylcarbamate xylylcarb; 3,4-xylyl N-methylcarbamate metolcarb; m-tolyl N-methylcarbamate isoprocarb; 2-isopropylphenyl N-methylcarbamate methoxadiazone; 5-methoxy- 3- (2-methoxyphenyl) -1,3,4-oxadiazole-2 (3
H) -one In addition, the carbamate-based insecticidal compound in the present invention includes a cyclic carbamate-based insecticidal compound such as methoxadiazone described above.

Various methods for microencapsulating an insecticidal compound are known, for example, JP-A-62-21550.
4, JP-A-62-215505 and JP-A-6-215505.
It is simple to use the interfacial polymerization method described in JP-A-3-22004, and the desired average particle size is (average particle size / film thickness).
It is easy to control the microencapsulation reaction so that a value can be obtained. Examples of the membrane material of the microcapsule include polyurethane, polyurea, polyamide, polyester, polycarbonate, polysulfonate, polysulfonamide and the like.

A more detailed description will be given by taking one of the methods for producing microcapsules of a polyurea film and a polyurethane film using the interfacial polymerization method as an example. Carbamate insecticidal compounds and polyisocyanates are mixed by adding solvents such as phenylxylylethane and methylnaphthalene, if necessary, and the resulting oil phase is poured into an aqueous phase containing a dispersant and stirred. While heating, a polyurea film is formed. It is also possible to form a polyurethane film by adding a polyhydric alcohol to the water phase before heating or before injecting the oil phase into the water phase. The film-forming reaction by the above-mentioned interfacial polymerization method is usually carried out at a temperature within the range of 40 to 80 ° C. for 1 hour or longer, preferably 1 to 48 hours. The obtained slurry can be used as it is as the composition of the present invention, but it is better to formulate it into a stable form which is easier to use.

[0006] As a specific formulation form, an aqueous suspension,
Powders, wettable powders, granules and the like, preferably aqueous suspensions are mentioned. The aqueous suspension is produced by adding a stabilizer such as a thickener, an antifreezing agent, an antiseptic and a specific gravity adjusting agent to the slurry obtained above. Examples of the thickener include xanthan gum, rhamsan gum, locust bean gum, carrageenan, natural polysaccharides such as welan gum, synthetic polymers such as polyacrylic acid sodium salt, semi-synthetic polymers such as carboxymethyl cellulose, aluminum magnesium silicate, and the like. Examples thereof include fine powders of mineral substances such as smectite, bentonite, hectorite and dry process silica, and substances having a thickening effect in water such as alumina sol. The amount of thickener added is
The amount is generally 10 parts by weight or less based on 100 parts by weight of the composition of the present invention, although it depends on the kind and the like. Examples of the antifreezing agent include propylene glycol and the like. The addition amount of the antifreezing agent is generally 20 parts by weight or less based on 100 parts by weight of the composition of the present invention. Examples of the antiseptic include those used in ordinary insecticidal preparations such as parahydroxybenzoic acid ester and salicylic acid derivatives, and examples of the specific gravity adjusting agent include water-soluble salts such as sodium sulfate and water-soluble fertilizers such as urea. Is mentioned. The content of the carbamate insecticidal compound in the composition of the present invention varies depending on the formulation form, but is generally 0.5 to 80% by weight, and particularly 0.5 to 50% by weight in the case of an aqueous suspension.

The composition of the present invention has an average particle size of microcapsules of 5 to 80 μm and an (average particle size / film thickness) value of 2
Although it is less than 00, the average particle diameter can be measured by using, for example, Coulter Counter TA-II type (manufactured by Coulter Electronics Co., Ltd., Nikkaki handling product). Further, it is easy to calculate the film thickness by the following formula.

[Equation 1] Here, D is the average particle size of the microcapsules, W _W is the weight of the membrane substance, W _C is the weight of the core substance, ρ _W is the density of the membrane substance, and ρ _C is the density of the core substance.

The composition of the present invention is particularly useful for controlling wood pests such as termites and flat beetles. When used for controlling termites, for example, the composition of the present invention or a diluted solution thereof is contained in an amount of 5 to 50 g / m ² as an active ingredient. Disperse the soil under the floor of the house or concrete surface. Alternatively, when used for xylem treatment, for example, the amount of active ingredient is 1 to 5 g /
About ² m ² is treated on the wood surface. When it is used for the control of flat beetle, it may be used as, for example, an insect-control plywood. As a specific example of the production of insect-repellent plywood, the composition of the present invention is mixed in an adhesive so that the amount of the active ingredient is about 10 to 1000 g per 1 m ^{3 of} plywood to prepare a paste for plate adhesion, and this paste is used. A method for obtaining a pest control plywood by laminating a single plate and pressurizing at a suitable temperature can be mentioned. Examples of the adhesive used include urea resin adhesives, melamine urea adhesives, modified phenolic resin adhesives, and alkali phenolic resin adhesives. Further, the composition of the present invention is effective not only for controlling wood pests but also for controlling unpleasant pests such as ants, horsetails, gudgeages, centipedes, wallworms, and pill bugs. In this case, for example, the composition of the present invention or a diluted solution thereof is contained in an amount of the active ingredient of about 1 to 50 g / m ² ,
It can be applied to unpleasant pests or habitats of unpleasant pests.

[0009]

EXAMPLES Next, the present invention will be described in more detail with reference to production examples, comparative examples and test examples. Production Example 1 Sumidur L-75 (Sumitomo Bayer Urethane Co., Ltd. aromatic isocyanate) 40 g and phenylxylylethane 1
After mixing 50 g with 150 g of Fenobucarb to make it uniform, add this to 400 g of an aqueous solution containing 17.5 g of gum arabic and 20 g of ethylene glycol, and add TK auto homomixer (homogenizer manufactured by Tokushu Kika Kogyo Co., Ltd.).
Was stirred and dispersed at room temperature (rotation speed: 5500 rpm) to obtain fine droplets. Then, the mixture was gently stirred at 60 ° C. for 24 hours to obtain a microcapsule slurry in which fenobucarb was encapsulated in a polyurethane film. 1 in the resulting slurry
260 g of an aqueous solution containing g of xanthan gum and 5 g of aluminum magnesium silicate was added to obtain a composition (1) of the present invention containing 15% by weight of fenocarb. The average particle size of the obtained microcapsules was 23.1 μm, and the (average particle size / film thickness) value was 70.

Production Example 2 The same procedure as in Production Example 1 was repeated except that 60 g of SUMIJUR L-75 was replaced with 40 g, and 280 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate was replaced with 260 g. Thus, a composition (2) of the present invention containing 15% by weight of fenocarb was obtained. The average particle size of the obtained microcapsules was 19.4 μm, and the (average particle size / film thickness) value was 48. Production Example 3 The same procedure as in Production Example 1 except that 220 g of an aqueous solution containing 80 g of Sumidule L-75 instead of 40 g and 1 g of xanthan gum and 5 g of aluminum magnesium silicate was used instead of 260 g were used. The composition (3) of the present invention containing Fenobucarb by weight was obtained. The average particle size of the obtained microcapsules was 21.1 μm, and the (average particle size / film thickness) value was 36.

Production Example 4 40 g of Sumidule L-75 and 150 g of phenylxylylethane were mixed with 150 g of fenocarb to homogenize the mixture, and this was mixed with 20 g of Gohsenol GL-05 (polyvinyl alcohol manufactured by Nippon Synthetic Chemical Industry Co., Ltd.). Add to 400 g of an aqueous solution containing 25 g of ethylene glycol,
K. Auto homomixer was used to stir and disperse at room temperature (rotation speed: 3700 rpm) to obtain fine droplets. Then 2 at 60 ℃
The mixture was gently stirred for 4 hours to obtain a microcapsule slurry in which fenobucarb was encapsulated in a polyurethane film.
260 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate in the obtained slurry.
Was added to obtain a composition (4) of the present invention containing 15% by weight of Fenobucarb. The average particle size of the obtained microcapsules was 8.1 μm, and the (average particle size / film thickness) value was 70.

Preparation Example 5 20 g of Sumidule L-75 and 150 g of phenylxylylethane were mixed with 150 g of fenocarb to make them uniform, and this was added to 400 g of an aqueous solution containing 15 g of gum arabic and 20 g of ethylene glycol. Using TK Autohomomixer, the mixture was stirred and dispersed at room temperature (rotation speed: 5500 rpm) to obtain microdroplets. Then 24 at 60 ℃
The mixture was gently stirred for a time to obtain a microcapsule slurry in which Fenobucarb was encapsulated in a polyurethane film. 280 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate was added to the obtained slurry to obtain a composition (5) of the present invention containing 15% by weight of fenocarb. The average particle size of the obtained microcapsules was 31 μm, and the (average particle size / film thickness) value was 141.

Production Example 6 A composition of the present invention containing 15% by weight of fenocarb was prepared by the same procedure as in Production Example 1 except that 15 g of gum arabic was used instead of 17.5 g and ethylene glycol 20 g was used instead of 25 g. 6) was obtained. The average particle size of the obtained microcapsules was 47.7 μm, and the (average particle size / film thickness) value was 70. Production Example 7 Sumidule L-75 20 g instead of 40 g, gum arabic 15 g instead of 17.5 g, 1 g of xanthan gum and 5 g of aluminum magnesium silicate were changed to 260 g and all were used except that 280 g was used. By the same operation as in 1, a composition (7) of the present invention containing 15% by weight of fenocarb was obtained. The average particle size of the obtained microcapsules was 21.5 μm, and the (average particle size / film thickness) value was 138. Production Example 8 40 g of Sumidule L-75 was mixed with 150 g of Fenobucarb which was heated and melted to make it uniform, and then 1
Add to 400 g of an aqueous solution containing 7.5 g of gum arabic and 30 g of ethylene glycol, stir and disperse at room temperature using a TK auto homomixer (rotation speed: 5500 rpm),
Microdroplets were obtained. Then, the mixture was gently stirred at 60 ° C. for 24 hours to obtain a microcapsule slurry in which fenobucarb was encapsulated in a polyurethane film. To the obtained slurry, 410 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate was added, and 15% by weight was added.
The composition (8) of the present invention containing the Fenobucarb of The average particle size of the obtained microcapsules was 19.7 μm,
The (average particle size / film thickness) value was 35.

Production Example 9 40 g of Sumidule L-75 and 150 g of phenylxylylethane were mixed with 150 g of Fenobucarb to make it uniform, and this was added to 400 g of an aqueous solution containing 17.5 g of gum arabic, and TK autohomomixer was added. Was stirred and dispersed at room temperature (rotation speed: 5500 rpm) to obtain fine droplets. Then, the mixture was gently stirred at 60 ° C. for 24 hours to obtain a microcapsule slurry in which fenobucarb was encapsulated in a polyurea film. 260 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate was added to the obtained slurry to obtain a composition (9) of the present invention containing 15% by weight of fenocarb. The average particle size of the obtained microcapsules was 21.3 μm, and the (average particle size / film thickness) value was 78.

Production Example 10 50 g of Sumidur N-75 (aliphatic isocyanate manufactured by Sumitomo Bayer Urethane Co.) and 1 of phenylxylylethane
After mixing 50 g with 150 g of Fenobucarb to make it uniform, add this to 400 g of an aqueous solution containing 17.5 g of gum arabic and 20 g of ethylene glycol, and stir-disperse at room temperature using a TK autohomomixer (rotation speed 5400 rpm), microdroplets were obtained. Then 24 at 60 ℃
The mixture was gently stirred for a time to obtain a microcapsule slurry in which Fenobucarb was encapsulated in a polyurethane film. To the resulting slurry, 250 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate was added to obtain a composition (10) of the present invention containing 15% by weight of fenocarb. The average particle size of the obtained microcapsules was 20.8 μm, and the (average particle size / film thickness) value was 69.

Production Example 11 The composition (2) of the present invention was added to 74.4 parts by weight of a urea resin for plywood.
8.7 parts by weight were added, and further 14.9 parts by weight of flour, 2
1.8 parts by weight of 0% by weight aqueous ammonium chloride and 0.2 parts by weight of water were added and mixed well to prepare an adhesive paste. 3 veneers with a moisture content of 7.5% by weight (18 cm x 18 cm, thickness 2 is 1.0 mm, one for the center is 2.5 mm), and the above-mentioned glue per 30.3 cm x 30.3 cm pasted with 30 g, 20 min cold pressed to (10kg / cm ²⁾ was added at room temperature, allowed to stand After depressurization for 30 minutes, further 115 to 125 ° C. for hot pressing (10 kg / cm
² ) was added for 90 seconds to produce plywood. At the time of manufacturing this plywood, no odor due to Fenobucarb was felt.

Comparative Example 1 The same procedure as in Preparation Example 1 was repeated except that 40 g of Sumidule L-75 was replaced with 40 g, and 290 g of an aqueous solution containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate was replaced with 260 g. Thus, a comparative composition (1) containing 15% by weight of Fenobucarb was obtained. The average particle size of the obtained microcapsules was 23 μm, and the (average particle size / film thickness) value was 273. Comparative Example 2 40 g of Sumidule L-75 and 150 g of phenylxylylethane were mixed with 150 g of Fenobucarb to homogenize it, and this was mixed with 40 g of Gohsenol GL-05 and 2
To 400 g of an aqueous solution containing 5 g of ethylene glycol was added, and the mixture was stirred and dispersed at room temperature using a TK Autohomomixer (rotation speed: 5000 rpm) to obtain microdroplets. Then 60
The mixture was gently stirred at 24 ° C. for 24 hours to obtain a microcapsule slurry in which Fenobucarb was encapsulated in a polyurethane film. Aqueous solution 2 containing 1 g of xanthan gum and 5 g of aluminum magnesium silicate in the obtained slurry.
60 g was added to obtain a comparative composition (2) containing 15% by weight of Fenobucarb. The average particle size of the obtained microcapsules was 2.7 μm, and the (average particle size / film thickness) value was 71.

Test Example 1 500 g of soil was treated with 50 g of a 1% by weight water-diluted solution of each composition shown in Table 1 below, the treated soil was placed in a petri dish, and 20 termite termite workers were released and 3 days later. Observed life and death. In addition, the treated soil under dark conditions of 40 ℃ 3
Similarly, for those stored for a month, 20 dead termite worker ants were similarly released, and life and death were observed 3 days later. The results are shown in Table 1.

[Table 1] As shown in the above table, the composition of the present invention is a composition effective for controlling termites over a long period of time.

Test Example 2 A box having a length of 50 cm, a width of 50 cm, and a depth of 30 cm was filled with soil so that the soil had a depth of 10 cm. L sprayed. Immediately after spraying and after storage at 40 ° C. for a predetermined number of days, 100 termite termite worker ants were released in each box, and life or death was observed on the next day. The results are shown in Table 2.

[Table 2]

Test Example 3 A glass petri dish having a diameter of 9 cm was treated with a water-diluted solution of each composition shown in Table 3 below so that the amount of active ingredient was 30 mg, and air-dried. After storing the dish at 40 ° C. for 2 weeks,
The residual ratio (%) was determined by measuring the amount of active ingredient remaining in the petri dish by gas chromatography. The results are shown in Table 3.

[Table 3]

Test Example 4 With respect to each composition shown in Table 4 below, acute oral toxicity was examined using ICR mouse (male). In Table 4, 3000mg
The mortality rate (%) when administering / kg is shown.

[Table 4] As shown in the table above, the composition of the present invention has reduced toxicity.

Test Example 5 The insect-repellent plywood obtained in Production Example 11 was cut into 8 cm × 5 cm pieces, an aluminum plate having 32 holes was stacked on the plywood plate, and the larva of Beetle beetle was put in each hole, and each hole was made with artificial feed. After burying, another insect-proof plywood (8 cm × 5 cm) obtained in Production Example 11 was placed on the aluminum plate. When the insect-repellent plywood was examined after storage for 2 months, no evidence of being bitten by the flaked flatworm was found.

[0023]

INDUSTRIAL APPLICABILITY The composition of the present invention is a composition with reduced toxicity capable of maintaining insecticidal efficacy for a long period of time and is effective for controlling wood pests and the like.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Seiji Inouchi 4-2-1 Takashi, Takarazuka-shi, Hyogo Sumitomo Kagaku Kogyo Co., Ltd. (72) Inventor Masao Ogawa 4-2-1 Takashi, Takarazuka-shi, Hyogo Sumitomo Chemical Co., Ltd.

Claims (4)

[Claims] 1. A microencapsulation characterized in that a carbamate insecticidal compound is encapsulated in a film having an average particle size of 5 to 80 μm and an (average particle size / film thickness) value of less than 200. Insecticidal composition. 2. The insecticidal composition according to claim 1, for controlling wood pests. 3. A carbamate insecticidal compound is fenobucarb, propoxur, xylylcarb, metolcarb,
It is 1 or more types chosen from an isoprocarb and a methoxadiazone, Claim 1 or Claim 2 characterized by the above-mentioned.
The insecticidal composition described. 4. The insecticidal composition according to claim 1, wherein the carbamate insecticidal compound is fenobucarb.