JPS6252721B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel oil-in-water suspension insecticidal and acaricidal composition. [In the formula, A represents an isopropyl group or a cyclopropyl group, and B represents a chlorophenyl group, bromophenyl group, tert-butylphenyl group, or 3,
4-methylenedioxyphenyl group, when B is a chlorophenyl group and A is an isopropyl group, R represents a fluorine atom, a chlorine atom or a bromine atom, and when B is a chlorophenyl group and A is a cyclopropyl group or B is a bromophenyl group, tert-
When it is a butylphenyl group or a 3,4-methylenedioxyphenyl group, R is a hydrogen atom, a fluorine atom,
Represents a chlorine atom or a bromine atom. ] A stable solution consisting of 1 to 50% by weight of one or more of the hydrophobic liquid insecticidal and acaricidal compounds shown below, 2 to 10% by weight of polyvinyl alcohol or gum arabic, an appropriate amount of a thickener, and residual water, The present invention also relates to a novel oil-in-water suspension insecticidal and acaricidal composition that is as effective as conventional formulations. Among the conventional pesticide formulations that are sprayed in liquid form, emulsions generally consist of a pesticide active ingredient, a synthetic surfactant, and a large amount of organic solvent. They often have drawbacks such as toxicity and irritation to plants and phytotoxicity to crops. On the other hand, powdered wettable powders are available as formulations that do not use organic solvents.
The fine powder scatters and is inconvenient to handle, and the high concentration and small amount of air spraying (300 ml per 10 ares)
ml or less) cannot be denied. For the above reasons, pesticide suspension compositions and aqueous emulsions in which hydrophobic pesticide ingredients are suspended and dispersed in fine particles using water as a base instead of organic solvents, powder carriers, etc. have been studied. . Since this type of composition is handled as a liquid, it does not generate dust when preparing the spray solution, and it is easy to handle quantitatively like a conventional liquid formulation. There are fewer problems with chemical damage to crops. However, in the suspension pesticide compositions that have been proposed so far, the hydrophobic pesticide active ingredient, which is the active ingredient, is mainly in solid form (Japanese Patent Application Laid-open No. 126635/1983,
JP-A-50-76236, JP-A-52-148625, U.S. Patent No. 4,071,617, etc.), oil-in-water type oil-in-water products using oily base materials generally have long-term stabilization of physical properties. It is considered difficult and has not been put into practical use. On the other hand, as an oil-in-water type agricultural chemical composition,
Publication No. 20520, Japanese Patent Application Laid-Open No. 1983-54547, Japanese Patent Application Publication No. 1972
There are aqueous emulsions such as those disclosed in Publication No. 122628, but these are solubilized types that use a large amount of general-purpose synthetic surfactants to reduce the particle size of the active ingredient to 0.1 μm or less, and have a large amount of interfacial Disadvantages such as high cost and toxicity due to the use of active agents have not been solved. The present inventors investigated the formulation of the compound represented by the above general formula () in order to compensate for the drawbacks of the conventional formulation form as described above, and as part of the study, a water-soluble polymer was used as a suspension aid. Various studies have been conducted on oil-in-water compositions. the result,
Among various water-soluble polymers, we found that polyvinyl alcohol or gum arabic is the most suitable as a suspension aid for the compound represented by the general formula (), and based on this knowledge, we further conducted various studies. The present invention has now been completed. That is, the present invention provides one or more hydrophobic liquid insecticidal and acaricidal compounds represented by the above general formula ().
50% by weight, more preferably 1-40% by weight, polyvinyl alcohol or gum arabic 2-10% by weight, plus appropriate amount of thickener, residual water. The present invention provides an insecticidal and acaricidal composition that has stable properties and is comparable in efficacy to conventional formulations.According to the present invention, organic solvents and synthetic surfactants that have been widely used in conventional formulations, such as Higher alcohol sulfate ester salt, higher alcohol sulfonate, alkyl sulfonate, aryl sulfonate, alkylaryl sulfonate and its formalin condensate, fatty acid ester compound, polyoxyethylene alkyl ether, polyoxyethylene alkyl A compound represented by the general formula () is mechanically dispersed and suspended as fine particles in an aqueous solution of polyvinyl alcohol or gum arabic without using aryl ether, polyoxyethylene phenylphenol derivatives, polyoxyethylene sorbitan alkylate, etc. To obtain a stable, highly effective, safe, and easy-to-handle insecticidal and acaricidal composition at a low cost by a simple operation such as stabilizing the fine particles by further adding an appropriate thickener. Can be done. Next, an outline of the manufacturing process of the composition of the present invention will be described. First, a predetermined amount of a hydrophobic liquid insecticidal and acaricidal compound represented by the general formula () is added to a 2 to 20% by weight aqueous solution of polyvinyl alcohol or gum arabic, heated to 60 to 70°C, and stirred with an ordinary stirrer. for example
Disperse and suspend using a TK homomixer (trade name of Tokushu Kika Kogyo Co., Ltd.) or a Shinagawa universal mixer (trade name of Sanei Seisakusho Co., Ltd.). The size of the insecticidal and acaricidal oil droplet particles suspended at this time is
Depending on the stirring intensity and the amount of polyvinyl alcohol or gum arabic added, the particle size will vary from approximately 1μ to 200μ.
Adjustment is possible within a range of μ. Finally, in order to prevent sedimentation of suspended particles and increase dispersion stability, an aqueous solution of a thickener is mixed in an appropriate proportion to obtain a suspended insecticidal and acaricidal composition that is stable for a long time. In the present invention, the insecticidal and acaricidal components include hydrophobic liquid compounds such as ceramic forms, optical isomers and/or geometric isomers of the compounds shown in the representative examples below, and mixtures containing these in arbitrary proportions. . Compound number Compound name (1) α-cyano-3-(4-bromophenoxy)
Benzyl 2-(4-chlorophenyl)isovalerate (2) α-cyano-3-(3-bromophenoxy)
Benzyl 2-(4-chlorophenyl)isovalerate (3) α-cyano-3-(4-chlorophenoxy)
Benzyl 2-(4-chlorophenyl)isovalerate (4) α-cyano-3-(4-fluorophenoxy)benzyl 2-(4-chlorophenyl)isovalerate (5) α-cyano-3-phenoxybenzyl 2-
(4-bromophenyl)isovalerate (6) α-cyano-3-phenoxybenzyl cyclopropyl-(4-chlorophenyl) acetate (7) α-cyano-3-phenoxybenzyl 2-
(4-tert-butylphenyl)isovalerate (8) α-cyano-3-phenoxybenzyl 2-
(3,4-methylenedioxyphenyl)isovalerate In the present invention, polyvinyl alcohol with a degree of polymerization of 1500 or less and a degree of saponification of 70 to 90 mol% is suitable, such as Gohsenol GL-
05 (Nippon Gosei Kagaku Kogyo Co., Ltd. product name, degree of polymerization
1000 or less, saponification degree of 86.5 to 89 mol%). Examples of thickeners include gum tragacanth,
Guar gum, sodium alginate, sodium carboxymethyl cellulose, sodium carboxymethyl starch, hydroxyethyl cellulose, methyl cellulose, polyacrylic acid and derivatives thereof can be used, and specific examples include commercially available Agrisol FL-100F and Agrisol FL-
104FA (product name of Kao Atlas Co., Ltd.), Primal ASE-60 (product name of Nippon Acrylic Co., Ltd.), Rheozik 250H (product name of Nippon Pure Chemical Co., Ltd.), Carbopol (product name of B, F, Gutsudoritsuchi Chemical Company) , Kerzan (trade name of Kelco Division of Merck Company), Begum (trade name of RT Vanderbilt Company), etc. The amount of these thickeners added is in the range of 0.1% to 20% by weight, but the optimum amount added varies depending on each thickener. The oil-in-water suspension insecticidal and acaricidal composition of the present invention obtained as described in detail above does not use any organic solvent, so it is flammable, has a bad smell from solvents, is toxic to humans, livestock, and small animals, is irritating, and does not contain any organic solvents. It is convenient in that there is no concern about chemical damage to the plants, it has good dilutability with water when preparing the spray solution, and it is easy to handle quantitatively like conventional liquid preparations. Next, the present invention will be explained in more detail using reference examples and examples. Reference Example 1 180 g of a 2% by weight aqueous solution of albumin, cellulose sulfate derivative, sodium alginate, carrageenan, polyvinylpyrrolidone, carboxymethyl cellulose, sodium lignin sulfonate, gelatin, gum arabic, and Gohsenol GL-05 was added with the hydrophobic substances listed in Table 1 below. Add 20 g each of liquid insecticidal and acaricidal ingredients (both racemic) and heat at 70°C using a TK homomixer until oil droplets of the insecticidal and acaricidal ingredients have a particle diameter of 1 to 100 μm (observed with a microscope). After dispersing them, each was sealed in a sealed glass container and kept at 60°C for 24 hours, and the dispersion stability of the insecticidal and acaricidal components was observed. The dispersion stability evaluation criteria are as follows. ○...No coalescence of oil particles is observed. △...Coalescence of oil-compatible particles is observed, but separation as an oil layer is not observed. ×...Oil-suitable particles coalesce and separate as an oil layer. The results are shown in Table 1.

【table】

[Table] Examples 1 to 7 Add 20 g of the insecticidal and acaricidal compounds listed in the table below to 40 g of a 10% by weight aqueous solution of Gohsenol GL-05, and stir for 5 minutes with a TK homomixer at 5000 rpm while heating at 70°C. did. Furthermore, by adding 40 g of a neutralized 25% by weight aqueous solution of Agrisol FL-100F at room temperature and mixing with gentle stirring for several minutes, 100 g of each oil-in-water suspension preparation with an active ingredient concentration of 20% by weight was obtained. Ta. The particle size range was 1 μm to 50 μm.

[Table] Example 8 The same operation as in Example 2 was carried out except that the rotation speed of the TK homomixer was changed to 2500 rpm, and (±)-α-cyano-3-(4-bromophenoxy) with an active ingredient concentration of 20% by weight was prepared. benzil
100 g of an oil-in-water suspension preparation of (±)-2-(4-chlorophenyl)isovalerate was obtained. Particle size width is 5
It was μ−150μ. Example 9 The same procedure as in Examples 1 to 7 was carried out except that 20 g of (±)-α-cyano-3-phenoxybenzyl (±)-2-(4-tert-butylphenyl)isovalerate was used. , (±)-α-cyano-3-phenoxybenzyl with an active ingredient concentration of 20% by weight.
100 g of an oil-in-water suspension of (±)-2-(4-tert-butylphenyl)isovalerate was obtained. The particle size range was 1μ to 60μ. Example 10 40 g of (±)-α-cyano-3-phenoxybenzyl (±)-2-(4-tert-butylphenyl)isovalerate, 10 g of Gohsenol GL-50
Example 1~
Perform the same operation as in step 7 to obtain an active ingredient concentration of 40% by weight.
100 g of an oil-in-water suspension preparation of (±)-α-cyano-3-phenoxybenzyl (±)-2-(4-tert-butylphenyl)isovalerate was obtained. The particle size range was 1 μm to 50 μm. Example 11 1 g of (±)-α-cyano-3-(4-bromophenoxy)benzyl (±)-2-(4-chlorophenyl)isovalerate, Gosenol GL-
40g of 5% aqueous solution of 05, Agrisol FL
Using 59 g of a neutralized 17% by weight aqueous solution of -100F, the same operations as in Examples 1 to 7 were carried out, and (±)-α-cyano-3-(4-
Bromophenoxy)benzyl (±)-2-(4-
100 g of an oil-in-water suspension preparation of chlorophenyl isovalerate was obtained. The particle size range was 1μ to 50μ. Example 12 20 g of (±)-α-cyano-3-phenoxybenzyl (±)-2-(4-tert-butylphenyl)isovalerate was added to 40 g of a 10% by weight aqueous solution of gum arabic.
g, and stirred for 5 minutes at 5000 rpm in a TK homomixer while heating at 70°C. Furthermore, 1% by weight of Rheozik 250H at room temperature.
Add 40g of the aqueous solution and mix with gentle stirring for several minutes, resulting in an active ingredient concentration of 20% by weight (±)-α
-cyano-3-phenoxybenzyl (±)-2
100 g of an oil-in-water suspension of -(4-tert-butylphenyl)isovalerate was obtained. The particle size range was 1μ to 70μ. Example 13 The stability of the composition of the present invention was tested using the composition obtained in Example 9. The results are shown in Table 2.

[Table] *Values based on content analysis values during preparation As is clear from the above table, the composition of the present invention is extremely stable both chemically and physically. Example 14 Three oil-in-water suspension preparations each having an active ingredient concentration of 20% by weight obtained in Examples 2, 6, and 9 (hereinafter referred to as compositions 2, 6, and 9, respectively). ) and three 20% by weight emulsions containing the same active ingredients as these oil-in-water suspension preparations (hereinafter referred to as control preparations 2, 6, and 9, respectively) at predetermined concentrations were added to Chinese cabbage on a turntable. to young plants of
Spray at a rate of 30 ml/2 pots, and after air drying, cut the leaves and put them in a polycup.
A group of 10 instar larvae were released, and the mortality rate on the second day was determined. The results are shown in Table 3.

[Table] As shown in the table above, it was confirmed that the composition of the present invention exhibited the same excellent efficacy as the control formulation at any dilution ratio. Example 15 The surfaces of tangerine leaves were brought into close contact with absorbent cotton moistened with water, and 20 adult female tangerine spider mites were released on the undersides of each tangerine leaf. This composition 2, 6, 9
and control formulations 2, 6, and 9 were diluted with water to make a 500 ppm solution, and 3 c.c. of the solution was sprayed on tangerine leaves, respectively. After 24 hours, the number of surviving insects was counted and the average mortality rate of each three replicates was determined. The results are shown in Table 4.

[Table] As shown in the table above, it was confirmed that the composition of the present invention exhibited the same excellent efficacy as the control formulation. Example 16 The mucous membrane irritation of the compositions of the present invention was investigated using Compositions 2, 6 and 9 as eye irritation in rabbits according to FDA guidelines [Federal Register, 37 , 8534 (1972)]. The results are shown in Table 5.

[Table] As is clear from the above results, it was confirmed that the composition of the present invention has no irritation.

Claims (1)

[Claims] 1. General formula [In the formula, A represents an isopropyl group or a cyclopropyl group, and B represents a chlorophenyl group, bromophenyl group, tert-butylphenyl group, or 3,
4-methylenedioxyphenyl group, when B is a chlorophenyl group and A is an isopropyl group, R represents a fluorine atom, a chlorine atom or a bromine atom, and when B is a chlorophenyl group and A is a cyclopropyl group or B is a bromophenyl group, tert-
When it is a butylphenyl group or a 3,4-methylenedioxyphenyl group, R is a hydrogen atom, a fluorine atom,
Represents a chlorine atom or a bromine atom. ] One or more of the carboxylic acid esters shown in
An oil-in-water suspension insecticidal and acaricidal composition comprising 50% by weight of polyvinyl alcohol or gum arabic, 2 to 10% by weight, a thickener, and residual water.