JPS60142901A - Granular agricultural chemical composition floating on water surface - Google Patents

Abstract

PURPOSE:The titled composition consisting of powder of a water-soluble carrier or a mixture of the powder with a grain nucleus, an inorganic or organic film- forming material having a lower water dissolution rate than that of the above- mentioned carrier and a slightly water-soluble agricultural chemical active constituent. CONSTITUTION:A composition consisting of (A) 70-98wt% powder of a water- soluble carrier, e.g. urea, ammonium sulfate potassium chloride, borax or sugar, or a mixture of the powder with a grain nucleus, (B) 1-10wt% inorganic or organic film-forming material, e.g. gum arabic, dextrin or sodium polyacrylate, having a lower water dissolution rate than that of the above-mentioned carrier and (C) 0.5-15wt% slightly water-soluble agricultural chemical active constituent having <=1% water-solubility (at 20 deg.C) and 5-15wt% water. The composition once sinks in water on application to water surface, but the carrier dissolves to float the components (C) with (B) and exhibit the chemical effect with high efficiency.

Description

Detailed Description of the Invention The present invention provides (al) a powder of a water-soluble carrier or a mixture of the powder and the core of a water-soluble aggregate; (bl) a water-soluble group velocity lower than that of the water-soluble carrier; The present invention relates to a water-floating agrochemical granular composition (hereinafter referred to as the present granule) characterized by containing an inorganic or organic film-forming substance having the following properties and a poorly water-soluble or water-insoluble agrochemical active ingredient (C1).

When this granule is dropped into water (such as in paddy fields), the water-soluble carrier dissolves in the water, allowing the poorly water-soluble or water-insoluble pesticide active substance to retain the air in the granule. The object of this invention is to float on the surface of water together with an inorganic or organic film-forming substance that retains air, thereby making it possible to efficiently use agricultural chemical active substances.

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 ingredient is highly adsorbed to the soil, and in order to control agriculturally harmful organisms on the water surface or in water, more active ingredient than necessary must be dropped, and it is also easily affected by water depth. There was room for improvement.

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, the granules themselves are immersed in water by treatment with a water repellent such as higher fatty acids. Floating method (Special Publication No. 48-1181, Special Publication No. 47-1240, Special Publication No. 48-1182, Special Publication No. 4
4-8600) JP-A-55-139308, JP-A-58-65203) ■ A method of retaining active ingredients in plastic granules with a specific gravity of 1 or less and making the granules themselves float on water (Japanese Patent Publication No. 48-1180) , Special Publication No. 49-24222
No., Special Publication No. 4.5-9560, Japanese Patent Publication No. 1393-1983
08) ■Solid sedimentation, using a substance as a core, coating the outer surface with a substance that floats in water such as a waxy substance, plastic, or inorganic foam together with an active substance, and removing the active substance from the core together with a floating carrier in water. Method of detaching and floating on the water surface (Special Publication No. 48-1!5613, Special Publication No. 58-26882)
The carbonates and solid acids of alkali metals or alkaline earth metals used in some of the materials of the 0 granules react in water to produce carbon dioxide gas, which causes the granules to float to the surface and release the active ingredients to 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.

That is, in method (2), the granules are light, so the advantage of granules, which is that they can be easily and evenly spread without being affected by wind, is lost.

Method (2) is expensive because the carrier itself is made of plastic, and it is also a material that generally has poor biodegradability, so there are concerns about pollution. Method (2) compensates for the drawbacks of (2) and (2) above, but the active ingredient is incorporated into floating plastics, waxy substances, adsorbent inorganic foams, etc., and the active ingredient cannot be eluted from these materials. The disadvantage is that the active ingredients do not spread sufficiently on the water surface because the water is suppressed.

In the method (2), the granules float to the surface and spread the active ingredients on the water surface, but because a mineral carrier is used repeatedly, some of the active ingredients remain adsorbed and disintegrate and settle again.
In some cases, the active ingredients cannot be fully utilized. In addition, there is a risk that carbon dioxide gas will gradually be generated due to atmospheric humidity during storage, and because it requires the use of solid acids, it is difficult to apply it to active ingredients that are chemically negative and unstable. There are drawbacks.

The inventors of the present invention have conducted extensive research considering the above points, and have found that uniform spraying on the water surface is less affected by wind, and that once submerged in water, the active ingredient floats to the surface together with some of the materials and spreads to the water surface. We have developed this granule that floats on the surface of water.

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 granule dissolves in water, and at this time most of the air contained in the granule is a three-dimensional structure (a type of network structure or hollow structure) formed of an air-retentive film-forming substance after the water-soluble carrier has been removed.
It is held in the water, exhibits a floating blade, and floats up along with the agricultural chemical active ingredients that are sparingly soluble or insoluble in water. The air-retentive film-forming substance used here retains the air contained in the whole grain and floats, so its own specific gravity may be 1 or more.
The granules of No. 613 and Japanese Patent Publication No. 513-26882 are fundamentally different. 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 as desired,
The active ingredient diffuses into the water from the water surface, making it possible to create a more efficient granule packaging in which the active ingredient is less adsorbed to the soil than sedimentary granules that diffuse from the soil surface.

The granules of the present invention are manufactured in detail by the following methods (1) to (2).

That is, a water-soluble carrier powder, or a water-soluble carrier powder and grain nuclei (hereinafter referred to as al), an air-retentive inorganic or organic film having a water-soluble group velocity lower than that of the water-soluble carrier. Using a forming substance (hereinafter referred to as (1)), a poorly water-soluble or water-insoluble agricultural chemical active ingredient (hereinafter referred to as CL), and water, (after kneading CL and water, Either molding into granules and drying to remove water, or kneading (al, +1)l and water, molding into granules, drying and removing water, and making the resulting granules retain (cl). , ■ (al 1 F')l, fcl and water are kneaded and dried to obtain granules, or ■ (at, (bl and water are kneaded and dried, then (cl 'l Either the grain nuclei of the water-soluble carrier of (al) are coated with a mixture of powder of the water-soluble carrier of (at) and (cl) using an aqueous solution of (bl) and dried. The granules of the carrier are coated with powder of a water-soluble carrier of (al) using an aqueous solution of (bl) and dried to retain (cl).

In addition, in the above methods ■ to ■, when kneading (al, (bl) and/or (cl) with water, water may not be used alone, but may be used in the form of an aqueous solution in which (bl is dissolved in advance). .

In addition, in methods (1) and (2), instead of using an aqueous solution of (l), water is used to prepare a powder of a water-soluble carrier of (al), (
The grain cores may be coated with bl and (cl and dried, or the granules obtained by coating the grain cores with powder of a water-soluble carrier of (at and drying) may be coated with (cl) using water. It may be retained.

What is common to the above ■～■ is [”' + (bl + (
Granules are obtained by mixing Cl and water, and finally water is removed from the granules by drying. During the above-mentioned mixing and when water is removed, air is taken into the granules, and this air is retained by the air-retentive adjuvant having the three-dimensional structure and causes the granules to float.

If the material remains in powder or granular form that does not maintain such a three-dimensional structure, such properties will not occur. Specifically, such a three-dimensional structure is first formed by (1) to (2).

For example, in the case of a method that does not use water, such as compression molding using a tablet machine, there is no buoyancy even if the same raw materials are used; Coating bodies and air-retentive film-forming materials with oily substances instead of water does not result in the floating properties of the present invention.

In addition, as a method for retaining 'poorly water-soluble acids or water-insoluble pesticide active ingredients in this granule, it is possible to mix or adsorb them in the powder of a water-soluble carrier in advance, or they can be adsorbed to the granules after drying. However, in the method of adsorption to granules, it is necessary to dissolve the crystalline active ingredient in a solvent in advance.

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. They 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 core of the water-soluble carrier is approximately 60% of the present granules, although it depends on the air-holding ability of the air-holding adjuvant.
It is preferable to use up to 99.4% by weight, preferably 70 to 98% by weight.

Next, examples of air-retaining organic or inorganic film-forming substances that can be used in this granule include gum arabic,
xanthan gum, dextrin, sodium salt of carboxymethyl cellulose, sodium alginate, starch,
Examples include, but are not limited to, polyvinyl alcohol, potassium silicate, sodium polyacrylate, etc., but those with a water solubility slower than the aqueous group velocity of the carrier powder used must be selected and used. No. Further, the above-mentioned auxiliary agents are used in an amount of 1 to 30 weight percent, preferably 1 to 10 weight percent, relative to the present granule.

In addition, water is absolutely necessary for producing the present granules, and the amount used is 3 to 25% by weight, preferably 5 to 15% by weight, based on the present granules.

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 agriculture, horticulture, and fisheries, as well as bollus and algae that occur in facilities that use water.

Specifically, 02O-diethyl thiophosphate (2-isopropyl-
(4-methyl-6-pyrimidyl), ■ (Diazinon) Thiophosphoric acid 0. O-dimethyl 0-(4-nitro-m-tolyl) (Sumithion) S-[111,2-bis(ethoxycarbonyl)ethyl]0,0-dimethyl dithiophosphate■ ゛(Marathon) 0,0-dimethyl thiophosphate 0-(4-methylthiom
0-2-chloro-1-(2,4-dichlorophenyl)vinyl phosphate 0.0-diethyl(hinifer) IJ y 0.0-dipropyl-0-'( 4-Methylthiophenyl) (Kayaphos) dithiophosphoric acid S-Cα-(ethoxycarbonyl)hensyl) 0.0-dimethyl(ersan) dithiophosphoric acid 0,0
-diethyl 5-(2-ethylthioethyl) (didistone) thioline eo, o-diethyl 0-(5-phenyl 13-
inoxadyl)(calphos)methylcarbamine e O
” 5ec-Butylphenyl (Bassa) O-isopropoxyphenyl methylcarbamate (Sunside) O-dichlor methylcarbamate (Mibucin) α-cyano-3-phenoxybenzyl 1-(p-ethoxyphenyl) -2,2-dichlordi Cyclopropanecarboxylate (cycloprothrin) 4-[(4-chloro-0-tolyl)oxy]■Ethyl butyrate (MCP in water) 2.4-bis(ethylamino)-6-methylthio1.3. 5-triazine (cymetrine) diethylthiocarbamic acid s-p-chlorbenzyl (Saturn) 5-tert-butyl-3-(2,4-dichloro-5
-inpropoxyphenyl) -1,3,4-oxadiazol-2(3H)-one (Ronsu), 0,0-diisopropyl S-benzi thiophosphate (Kitadine P), etc. It is used in an amount of 0.1 to 20% by weight, preferably 0.5 to 15% by weight, based on the granules, but each active ingredient may be mixed and used, and the active ingredients are limited to those listed here. not.

The condition for this granule to float is that the specific gravity is 1 or less while retaining air, and the air-retentive film-forming substance and agricultural chemical active ingredient must be used within this range. As long as it satisfies the above requirements, auxiliary agents such as solvents, surfactants, and water-insoluble or poorly water-soluble carriers may also be included. Activates nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants that are normally used in agricultural and horticultural emulsions and irrigation agents. You can choose and use it according to the ingredients.

Solvents are mainly used to dissolve the active ingredient, reduce viscosity, and make it easier for the active ingredient to spread on the water surface, and are not particularly limited, but include dioctyl phthalate, methylnaphthalene, and butylbenzyl. High boiling point solvents such as phthalate, dibutyl phthalate, tricresyl phosphate are preferred.

Further, as the non-aqueous or poorly water-soluble carrier, clay, talc, bentonite, etc. are preferable.

This granule is especially suitable for harmful insects such as agricultural pests that live near the water surface, such as the brown flycatcher, rice weevil, brown leafhopper, black leafhopper, green leaf beetles, and medium-sized leafhoppers.
Suitable for controlling weeds such as Japanese cabbage. For example, if an active ingredient with a high vapor pressure such as the insecticide diazinon is used, it will have an efficient gas effect on the black leafhopper, brown leafhopper, etc. on the water surface, and an active ingredient with a strong contact effect like gropaphos will have a gas effect on the rice weevil, etc. It is especially effective for rice plants that float on water and for organisms that move back and forth in 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 only.

In addition, "1 part" indicates a part by weight, and "%" indicates a weight %.

Example 1゜Diazinon 5 parts Sodium silicate °) Rum 3 parts Anhydrous sodium sulfate 92 parts were uniformly mixed and ground, and 8 parts of water was added and kneaded.
．． After granulation using a 9m screen extrusion granulator,
Dry and sieve with 12-32 mesh diazinon 5%
Obtained a product containing.

Example 2 50 parts of anhydrous sodium sulfate granules of 12 to 28 menshies were coated with 10 parts of a sodium silicate aqueous solution prepared by diluting 50 parts of pentahydrate sodium borate powder to 25%, and then dried to obtain granules. Ta. Furthermore, 5 parts of diazinon was added to 95 parts of this granular material.
A portion was adsorbed and sieved through 12 to 32 meshes to obtain a product containing 5% diazinon.

Example 3 3 parts of gum arabic 97 parts of ammonium sulfate were uniformly mixed and pulverized, 10 parts of water was added and kneaded. ~32 mesh granules are obtained.

2 parts of cycloprothrin diluted to 50% with dioctyl phthalate was adsorbed onto 98 parts of the granules to obtain a product containing 1% cycloprothrin.

Example 4 Simetrine 1.5 parts Gum arabic 3.0 parts Sodium chloride 94.5 parts were mixed and pulverized uniformly, and 10 parts of water was added and kneaded.
Granulate with an extrusion granulator with a diameter of 0.9 mm, and after drying
Obtain ~32 mesogranules. 1 part of MCP in water was adsorbed to 99 parts of the granules to obtain a product containing 1% MCP and 1.5% cymetrine in water.

A control example used in the test of the above example is described below.

Control example 1. (For Examples 1 and 2) Diazinon 5 was added to 92 parts of limestone grains of 12-32 mesh.
1 part was coated with 3 parts of white carbon to obtain granules containing 5% diazinon.

Control example 2. (For Example 3) 98 parts of 12 to 32 mesh pumice and 7 dioctyl
-) Two parts of cycloprotrin diluted to 50% were adsorbed to obtain granules containing 1% cycloprotrif.

Control example 3. (For Example 4) Simetrine 1.5 parts Bentonite 20.0 parts Merck 75.0 parts Sodium ligninsulfonate 2.0 parts Sodium dodecylbenzenesulfonate 0.5 parts were kneaded with 17 parts of water, and the diameter After granulation using an extrusion type granulator with a 0.9 size screen, it was dried to obtain sieved granules with 12 to 32 meshes. 1 part of MCP in water was adsorbed onto 99 parts of the granules to obtain granules containing 1% MCP and 1.5% cymetrine in water.

The results of tests conducted on the brown planthopper, rice weevil, and duckweed using the above-mentioned examples will be described below.

Test example 1. Test against the brown planthopper The granules of the present invention (Example J
, 2) and as a comparison, 10 grains of Control Example were applied from above the water, and at regular intervals, a glass cylinder was placed over the bot, and 20 female adult brown planthoppers were released into each cylinder, and the lid 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 bot was 1 cm and 3 crn and 15 crn.

Test results Test example 2 Test against rice weevil Granules of the present invention (Example 3)
For comparison, Control Example 20 granules were applied over water, and the rice plants were covered with a wire mesh cylinder at regular intervals, and 20 adult rice weevils were released into the cylinder.The rice plants were then covered with wire mesh and died after 24 hours. We counted the number of insects and determined the mortality rate.

Test Results Test Example 37 Test on duckweed, carried out after pouring water into the throat of a 1/20.00 are plastic tube to a depth of 5 cm, and placing duckweed in such a way that about half of the surface area of the water was covered. Example 40
Granules and Control Example 30 granules were applied for comparison, and the herbicidal index was determined for each fixed period.

Weed killing index No evidence of death of duckweed Weed killing index Less than 0.20% 1 About 20-40% 2 About 40-'60% 3 About 60-80% 4 About 80% or more 5 Completely dead 6 Any test Both examples sank once after being dropped into water, but then floated to the surface, showing a higher pesticidal effect than the control example.

Patent applicant Nippon IC Yaku Co., Ltd.

Claims (1)

Scope of Claims: (II (al) a powder of a water-soluble carrier or a mixture of the powder and grain nuclei of a water-soluble carrier, (bl) an inorganic material having a water-soluble group velocity lower than that of the water-soluble carrier; or a water-floating agricultural chemical granular composition characterized by containing an organic film-forming substance and (C1m) a water-soluble or water-insoluble agricultural chemical active ingredient.