JPS6330281B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention provides (1) (a) a powder of a water-soluble carrier or a mixture of the powder and grain nuclei of the water-soluble carrier; (b) an inorganic or (2) (a), (b) and Molding the mixture containing (c),
(d) is retained in the granules obtained by drying, or (3) the grain nuclei of the water-soluble carrier in (a) are mixed with the aqueous solution in (b).
Either the water-soluble carrier powder of (a) and (d) are coated with a mixture and dried, or the grain cores are coated with the water of (c) and the water-soluble carrier powder (a) is coated with a mixture of (a) and (d). b) and (d) are coated and dried, or (4) the grain nuclei of the water-soluble carrier in (a) are coated with the aqueous solution in (b).
(d) can be retained in the granules obtained by coating with powder of the water-soluble carrier of (a) and drying, or by using water of (c) instead of using the aqueous solution of (1). ) powder and (b)
The present invention relates to a water surface-floating agricultural chemical granular composition (hereinafter referred to as the present granule), which is obtained by coating (a) on the granule core and drying the resulting granules to retain (d). When this granule is dropped into water (such as in a paddy field), the water-soluble carrier dissolves in water, and the poorly water-soluble or water-insoluble pesticide active ingredient is released into the air in the granule. The purpose is to float on the surface of water together with a retentive inorganic or organic film-forming substance, thereby making it possible to efficiently use agricultural chemical active ingredients. Conventionally, when many granules for water surface application containing poorly water-soluble pesticide active ingredients are applied to the water surface, they are submerged in water, and after reaching the soil surface, the active ingredients are released little by little into the water, or bentonite is used. It was made to diffuse the active ingredient onto the soil surface together with a water-insoluble carrier such as clay, but with swelling and affinity for water. Therefore, the active ingredients are highly adsorbed into the soil, and in order to control agriculturally harmful organisms on or in the water, it is necessary to drop more active ingredients than necessary, and it is also easily affected by water depth, so it is difficult to improve the soil. There was room. From this point of view, floating granules have been studied as a method for more efficiently utilizing active ingredients. For example, the active ingredient is held in a light carrier that floats on water, such as foamed obsidian, pumice, or calcined perlite, and if necessary, a water repellent such as a higher fatty acid is treated to make the granules themselves float on water. Method (Special Publication No. 1181, Special Publication No. 1181, Special Publication No. 1240, Special Publication No. 1977, Special Publication No. 1240, Special Publication No. 1977)
No. 1182, Special Publication No. 1986-8600, No. 139308 of Special Publication No. 1987-139308
(Japanese Patent Publication No. 58-65203), a method of retaining the active ingredient in plastic granules with a specific gravity of 1 or less and making the granules themselves float on water (Japanese Patent Publication No. 1180-1980, Japanese Patent Publication No. 1180-1989,
−24222 No. 45-9560, Unexamined Patent Publication No. 1977-
139308), the core is a solid sedimentary substance, and its outer surface is coated with a substance that floats on water, such as a waxy substance, plastic, or inorganic foam, together with an active ingredient, so that the active ingredient is released from the core together with a floating carrier in water. method of making it float on the water surface (Special Publication No. 48-15613, Special Publication No.
58-26882), alkali metal or alkaline earth metal carbonates and solid acids used in some of the granule materials react in water to produce carbon dioxide gas, which causes the granules to float. A method of spreading active ingredients on the water surface (Japanese Patent Publication No. 47-27930) has been disclosed. However, each method has advantages and disadvantages, and none of them have been put into practical use. In this method, since the granules are made lighter, the advantage of granules, which is that they can be easily and uniformly dispersed without being affected by wind, is lost.
In this method, the carrier itself is made of plastic, which is expensive, and the material generally has poor biodegradability, so there are concerns about pollution. Although this method compensates for the above disadvantages, the active ingredient is incorporated into floating plastics, waxy substances, adsorbent inorganic foams, etc., and the elution of the active ingredient from these materials is suppressed. Therefore, there is a drawback that the active ingredient does not spread sufficiently on the water surface. In this method, the granules float to the surface and spread the active ingredient on the water surface, but
Since a mineral carrier is used as the material, some of the active ingredients will disintegrate and settle again while being adsorbed, so the active ingredients may not be fully utilized.
In addition, there is a risk that carbon dioxide gas will gradually be generated due to atmospheric humidity during storage, and since it requires the use of a solid acid, it is difficult to apply it to active ingredients that are chemically unstable on the acidic side. There are drawbacks. The inventors of the present invention have considered the above points and have conducted intensive research, and as a result, they have found that uniform spraying on the water surface is less affected by wind.
We have developed this granule that floats on the water surface, where once submerged in water, the active ingredient floats up along with some of the ingredients and spreads over the water surface. When this granule is applied to the water surface, it is temporarily submerged in water because it has a specific gravity of 1 or more. Next, the water-soluble carrier in the granules is dissolved in water, and at this time, most of the air contained in the granules forms a three-dimensional structure formed by the air-retentive film-forming material after the water-soluble carrier has escaped. (a type of network structure or hollow structure), exerts a buoyant force, and floats up together with the agricultural chemical active ingredient that is sparingly soluble or insoluble in water. The air-retaining film-forming material used here retains the air contained in the entire grain and floats to the surface.
The specific gravity itself may be 1 or more, and is fundamentally different from the granules of Japanese Patent Publication No. 48-15613 and Japanese Patent Publication No. 26882-1982 mentioned above. The active ingredient floating on the water surface is trapped on the water surface because the substance used as an air retention agent ultimately dissolves in the water, and it exerts its medicinal effect quickly and efficiently. Furthermore, by containing a surfactant if desired, the active ingredient diffuses from the water surface into the water, creating an efficient granule with less adsorption of the active ingredient to the soil than a settling type granule that diffuses from the soil surface. You can also do that. The granules of the present invention are manufactured in detail by the following methods. In other words, a water-soluble carrier powder, a water-soluble carrier powder and granules (hereinafter referred to as (a)), an air-retentive inorganic or organic material having a water dissolution rate lower than that of the water-soluble carrier. Film-forming substances (hereinafter referred to as (b)), water (hereinafter referred to as (c)), and sparingly water-soluble or water-insoluble pesticide active ingredients (hereinafter referred to as (d))
After kneading (a), (b), (c), and (d) using ), then molded into granules and watered with
Either (d) is retained in the granules obtained by drying and removing (c), or (a), (b), (c), and (d) are kneaded and dried to obtain granules. After kneading and drying a), (b), and (c), (d) is retained in the resulting granules, or the granules of the water-soluble carrier in (a) are mixed with the aqueous solution in (b).
Either coat with a mixture of the powder of the water-soluble carrier in (a) and (d) and dry it, or coat the granules of the water-soluble carrier in (a) with the aqueous solution in (b).
(d) is retained in the granules obtained by coating with the water-soluble carrier powder of (a) and drying. In addition, in the above methods ~, when kneading (a), (b) and/or (d) with water (c), water (c)
may not be used alone, but may be used in the form of an aqueous solution in which (b) is dissolved in advance. In addition, in the method of and, instead of using the aqueous solution of (b), water (c) is used to coat the grain nuclei with the water-soluble carrier powder of (a), (b) and (d), and then dried. You can also
Alternatively, (d) may be retained in granules obtained by coating (a) water-soluble carrier powder and (b) on granule cores using water (c) and drying. What is common to ~ above is that (a), (b), (c), and (d) are mixed to obtain granules, and finally water (c) is mixed from this granule.
is dried and removed. During the above-mentioned mixing and when water (c) is removed, air is taken into the granules, and this air is retained by the air-retaining auxiliary agent with the three-dimensional structure, causing the granules to float. Let it happen. If the material remains in powder or granular form that does not maintain this three-dimensional structure, such properties will not occur. Specifically, such a three-dimensional structure is first formed by ~. For example, in the case of methods that do not use water (c), such as compression molding using a tablet machine, there is no buoyancy even if the same raw materials are used, and the same water-soluble Even if the powder of the carrier and the air-retaining film-forming substance are coated with an oily substance instead of water (c), the floating property as in the present invention does not occur. In addition, methods for retaining poorly water-soluble or water-insoluble agricultural chemical active ingredients in this granule include mixing or adsorbing it into a water-soluble carrier powder in advance, or adsorbing it to the granules after drying. good. Specific examples of the water-soluble carrier powder used in the present invention include powders of urea, ammonium sulfate, ammonium nitrate, ammonium chloride, potassium chloride, ammonium bicarbonate, sodium sulfate, borax, sodium carbonate, sugars, etc. , these may be used alone or in combination, and are not limited to these. Further, examples of the grain core of the water-soluble carrier include granules having the same components as the powder of the water-soluble carrier described above. The powder and granule cores of the water-soluble carrier are characterized by their air retention (b)
Although it depends on the air retention capacity of
It is recommended to use 60 to 99.4% by weight, preferably 70 to 98% by weight. Next, the air-retentive organic or inorganic film-forming substances (b) that can be used in this granule include gum arabic, xanthan gum, dextrin, sodium salt of carboxymethyl cellulose, sodium alginate, modified starch, and polyvinyl alcohol. , polyethylene oxide, sodium silicate, potassium silicate, sodium polyacrylate, etc., these may be used alone or in combination of two or more, and the water-soluble carrier used is not limited to these. It is necessary to select and use a material that has a water dissolution rate slower than that of . In this way, selecting and using a film-forming substance that has a slower dissolution rate in water than the water-soluble carrier is important because, as mentioned above, when the present granules are applied to the water surface, as the water-soluble carrier is removed in the water,
This is an essential requirement for the three-dimensional network structure formed by the film-forming substance to hold the air pressurized and enclosed in the granules that expand and produce, and for the granules to exhibit levitation force. Further, these (b) are preferably used in an amount of 1 to 30% by weight, particularly preferably 1 to 10% by weight, based on the granules. In addition, when manufacturing this granule, be sure to use water.
(c) is necessary, but the amount used is 3
-25% by weight, preferably 5-15% by weight. Next, the agricultural active ingredients that can be used in this granule include any poorly water-soluble or water-insoluble ingredients with a water solubility (at 20°C) of 1% or less and which are active in controlling harmful organisms when applied to the water surface. For example, it has the activity of controlling insects, weeds, and diseases that harm useful plants in the fields of agrochemicals, horticulture, and fisheries, as well as insects, algae, and the like that occur in facilities that use water. Specifically, O,O-diethyl O-(2-isopropyl-4-methyl-6-pyrimidyl) thiophosphate (Diazinon) O,O-dimethyl O-(4-nitro-m-tolyl) thiophosphate (Sumithion) S-[1,2-bis(ethoxycarbonyl)ethyl]O,O-dimethyl dithiophosphate (Marathon) O,O-dimethyl thiophosphate O-(4-methylthio-m-tolyl) (Bisito) Phosphoric acid O-2 -Chlor-1-(2,4-dichlorophenyl)vinyl O,O-diethyl (vinifate) O,O-dipropyl-O-(4-methylthiophenyl) phosphate (Kayafuos) S-[α-(ethoxy) dithiophosphate carbonyl)benzyl]O,O-dimethyl (elsan) O,O-diethyl dithiophosphate S-(2-ethylthioethyl) (dicyston) O,O-diethyl thiophosphate O-(5-phenyl-3-isoxadyl) ( Calphos) O-sec-butylphenyl methylcarbamate (Batsusa) O-isopropoxyphenyl methylcarbamate (Sunside) O-cumenyl methylcarbamate (Mipsin) α-cyano-3-phenoxybenzyl 1- (p
-ethoxyphenyl)-2,2-dichlorocyclopropanecarboxylate (cycloprothrin) 4-[(4-chloro-O-tolyl)oxy]ethyl butyrate (MCP in water) 2,4-bis(ethylamino) -6-Methylthio-1,3,5-triazine (simetrine) S-p-chlorobenzyl diethylthiocarbamate (Saturn) 5-tert-butyl-3-(2,4-dichloro-
5-isopropoxyphenyl)-1,3,4-
Oxadiazol-2(3H)-one (Lonestar), O,O-diisopropyl thiophosphate S-benzylthiophosphate (Kitazine P), 3-isopropoxy-2-methylbenzanilide (mepronil), etc. 0.1 to 20% by weight of this granule,
It is preferably used in an amount of 0.5 to 15% by weight, but a mixture of each active ingredient may be used, and the active ingredients are not limited to those listed here. The condition for this granule to float is that the specific gravity becomes 1 or less while retaining air as the water-soluble carrier escapes from the water, and the air-retentive film-forming substance and agricultural chemical active ingredient must be within the range that satisfies this condition. However, as long as this condition is met, auxiliary agents such as solvents, surfactants, and water-insoluble or poorly water-soluble carriers can be added. The surfactants mentioned here are mainly used to diffuse active ingredients into water and spread on the water surface, and are usually nonionic surfactants used in agricultural and horticultural emulsions and wettable powders. Anionic surfactants, cationic surfactants, and amphoteric surfactants may be selected and used depending on the active ingredient. Solvents are mainly used to dissolve the active ingredient and reduce its viscosity, and to make it easier for the active ingredient to spread on the water surface.Solvents include, but are not limited to, dioctyl phthalate, methylnaphthalene, and dioctyl adipate. , butylbenzyl phthalate, dibutyl phthalate, tricresyl phosphate,
High boiling point solvents such as butyl oleate are preferred. Further, as the water-insoluble or slightly water-soluble carrier, clay, talc, white carbon, bentonite, etc. are preferable. The above organic solvent or surfactant is
For example, when mixing (a), (b), (c), and (d) in the method of It can be blended when making the granules hold (d). This granule is particularly suitable for harmful insects that live near the water surface, such as harmful insects such as the brown flycatcher, rice weevil, brown leafhopper, and black leafhopper, weeds such as leafhopper, duckweed, and sagebrush, and disease-causing fungi such as caterpillar disease and sheath blight. Suitable for controlling pests. For example, if an active ingredient with a high vapor pressure such as the insecticide diazinon is used, it will efficiently show a gas effect on black leafhoppers, brown leafhoppers, etc. on the water surface, and active ingredients with a strong contact effect like propaphuos will show a gas effect on waterborne leafhoppers such as rice water weevils. It is particularly effective against organisms that move between rice and water.
Furthermore, when an active ingredient with herbicidal power is used, it is effective against the above-mentioned weeds that frequently come into contact with water systems. Next, some examples and test examples will be shown, but the present invention is not limited to these. still,
"Part" indicates part by weight, and "%" indicates weight %. Example 1 10 parts of a 30% aqueous solution of sodium silicate was added to 97 parts of anhydrous sodium sulfate powder, kneaded, and granulated using an extrusion granulator with a screen of 0.9 mm in diameter.
Dry to obtain 12-32 mesh granules. 5 parts of diazinon was adsorbed onto 95 parts of the granules to obtain a product containing 5% diazinon. Example 2 50 grains of anhydrous sodium sulfate with 12 to 28 meshes
After coating 50 parts of pentahydrate sodium borate powder with 10 parts of sodium silicate aqueous solution diluted to 25%,
Granules were obtained by drying. Furthermore, 5 parts of diazinon was adsorbed onto 95 parts of the granules and sieved through 12 to 32 meshes to obtain a product containing 5% diazinon. Example 3 0.5 parts of xanthan gum, 1.5 parts of sodium polyacrylate, and 98.0 parts of potassium chloride were uniformly mixed and ground, and 10 parts of water was added and kneaded.
After granulation using an extrusion granulator with a 0.9 mm diameter screen, it is dried to obtain 12 to 32 mesh granules. Add 50 parts of dioctyl adipate to 98 parts of this granulate.
A product containing 1% cycloprothrin was obtained by adsorbing 2 parts of cycloprothrin diluted to 1%. Example 4 Simetrine 1.5 parts Sodium salt of carboxymethyl cellulose
After uniformly mixing and pulverizing 3.0 parts of sodium chloride and 94.5 parts of sodium chloride, adding 10 parts of water and kneading, the mixture was granulated using an extrusion granulator with a diameter of 0.9 mm and dried.
Obtain 12 to 32 mesh granules. By adsorbing 1 part of MCP in water to 99 parts of this granular material, 1% MCP in water is obtained.
A product containing 1.5% simetrine was obtained. Example 5 3 parts of xanthan gum and 97 parts of potassium chloride were uniformly mixed and ground, and 10 parts of water was added and kneaded.
After granulation using an extrusion granulator with a screen of 0.9 mm in diameter, it is dried to obtain 12 to 32 mesh granules. 5 parts of dioctyl phthalate to 90 parts of this granule
After adsorbing 5 parts of mepronil, a product containing 5% of mepronil was obtained by coating 5 parts of mepronil. A control example used in the test of the above example is described below. Control Example 1 (Compared to Examples 1 and 2) 92 parts of limestone grains of 12 to 32 meshes were coated with 5 parts of diazinon along with 3 parts of white carbon to obtain granules containing 5% diazinon. Control Example 2 (Compared to Example 3) Two parts of cycloprothrin diluted to 50% with dioctyl phthalate were adsorbed on 98 parts of pumice of 12 to 32 meshes to obtain granules containing 1% of cycloprothrin. Control example 3 (relative to Example 4) Simetrine 1.5 parts Bentonite 20.0 parts Talc 75.0 parts Sodium ligninsulfonate 2.0 parts Sodium dodecylbenzenesulfonate
After kneading 0.5 parts with 17 parts of water and granulating it using an extrusion type granulator with a screen of 0.9 mm in diameter, it was dried and
A sieved granulate was obtained at ~32 meshes. This particulate matter
Adsorb 1 part of MCP in water to 99 parts to make MCP1 in water.
%, cymetrine 1.5% granules were obtained. Control example 4 (relative to Example 5) Mepronil 5.0 parts Bentonite 20.0 parts Clay 72.5 parts Sodium ligninsulfonate 2.0 parts Sodium dodecylbenzenesulfonate
0.5 part was mixed with 17 parts of water, granulated using an extrusion granulator with a screen of 0.9 mm in diameter, and then dried.
Sieve through ~32 meshes to obtain granules containing 5% mepronil. Using the above Examples and Control Examples, the results of tests against the brown planthopper, rice weevil, duckweed, and rice sheath blight fungus will be described below. Test Example 1 Test against the brown planthopper The granules of the present invention (Examples 1 and 2) and the granules of Control Example 1 as a comparison were applied from above water to rice plants planted in magnetic pots of 1/50,000 are. The pot was covered with a glass cylinder, 20 female adult brown planthoppers were released into the pot, and the pot was covered with a wire mesh. After 24 hours, the number of dead insects was counted and the mortality rate (%) was determined. Water was replenished every day so that the water depth in the pot was 1 cm, 3 cm, and 5 cm.

[Table] Test Example 2 Test against rice weevil Rice grains of the present invention (Example 3) and Control Example 2 were applied to rice planted in a pot of 1/50,000 are.
The granules were applied over water, the rice plants were covered with a wire mesh cylinder at regular intervals, 20 adult rice weevils were released into the cylinder, the lid was covered with a wire mesh, and the number of dead insects was counted after 24 hours. The mortality rate was calculated.

[Table] Test Example 3 Test on duckweed Water was poured into a 1/2000 are plastic bucket to a depth of 5 cm, and duckweed was added to cover about half of the surface area of the water. 4) and as a comparison, the granules of Control Example 3 were applied, and the herbicidal index was determined for each fixed period.

[Table] Death test example 4 Test against rice sheath blight The granules of the present invention (Example 5) and the granules of Control Example 4 were applied from above water to rice plants planted in porcelain pots with an area of 1/50,000. After 5 days, the rice sheath blight fungus previously cultured in a barley medium was inoculated onto the base of the rice plant, maintained at around 28°C, and after 5 days, the disease index was calculated according to the following criteria. Morbidity level 0: Healthy 1: Small or incomplete lesion formation is observed. 3: Large or clear lesions are observed. 5: Large or clear lesions are observed and are spreading further upwards of the damaged area. Morbidity index per pot = (0×n ₀ +1×n ₁ +3×n ₃ +5
×n ₅ )/(n ₀ +n ₁ +n ₃ +n ₅ )×5×100 (however, n ₀ , n ₁ , n ₃ , and n ₅ indicate the number of stems at each disease severity level.)

[Table] After being dropped into water, all of the test examples sank, but then floated to the surface, showing a higher pesticidal effect than the control example.

Claims (1)

[Scope of Claims] 1 (a) a powder of a water-soluble carrier or a mixture of the powder and grain nuclei of the water-soluble carrier; (b) an inorganic substance having a water dissolution rate lower than that of the water-soluble carrier; or an organic film-forming substance; (c) water; and (d) a poorly water-soluble or water-insoluble pesticide active ingredient. ) is molded into a mixture,
(d) is retained in the granules obtained by drying, or the grain cores of the water-soluble carrier (a) are mixed with the aqueous solution (b).
The powder of the water-soluble carrier of (a) is coated with a mixture of the powder of the water-soluble carrier of (a) and (d) and dried, or the water of (c) is used on the grain core to form the powder of the water-soluble carrier of (a). (b) and (d) are coated and dried, or the grain nuclei of the water-soluble carrier (a) are coated with the aqueous solution of (b).
The granules obtained by coating with a powder of the water-soluble carrier of (a) and drying may retain (d), or the water of (c) may be used instead of the aqueous solution of (b). ) powder and (b)
1. A water surface floating agricultural chemical granular composition, characterized in that it is obtained by coating (a) on the granule cores and drying the resulting granules to retain (d). 2 Organic solvent or surfactant (a), (b), (c), (d)
It is formulated when mixing, molded and dried or
(d) to the granules obtained by mixing (a), (b), and (c), molding, and drying
The water-floating agricultural chemical granular composition according to claim 1, which is obtained by blending the water surface-floating agricultural chemical granular composition when retaining the following.