JPS6317802A - Granular insecticide for application to water surface - Google Patents

Abstract

PURPOSE:A granular insecticide for application to water surface that is prepared by allowing a carrier to hold a combination of insecticidal ingredients hardly soluble or insoluble in water with a high-boiling solvent as a floating substance, thus being optimally used as an insecticide for controlling insect pests living around water surface, because it can effectively disperse in water. CONSTITUTION:The objective insecticide for application to water surface is prepared by allowing a solid carrier such as potassium chloride, talc, kieselguhr or the like, to hold insecticidal ingredients hardly soluble or insoluble in water, e.g., 2-(4-ethoxyphenyl)-2-methylpropyl 3-phenoxybenzyl ether, and a high boiling solvent of 1 or less density such as n-butyl laurate, di-2-ethylhexyl adipate as a floating substance. The application of the insecticide to water surface enables the active ingredients to disperse in water effectively and to manifest their effect efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a water surface application granule for agrochemicals.Specifically, the agrochemical is applied to the water surface to effectively disperse the active ingredient in the water,
This invention relates to granules that more effectively exhibit the effects of active ingredients.

In particular, the present invention relates to granules that can be applied to the water surface to control aquatic pests and pests that have a life cycle near the water, and that effectively disperse the active ingredients in the water and more effectively exhibit the effects of the active ingredients.

[Prior art]

Conventionally, many attempts have been made to effectively utilize insecticides in the form of granules. Recently, some insecticides have been put into practical use, and their widespread use, along with their usefulness, is attracting a lot of attention.Insecticides are inherently more acutely toxic than other pesticides, and their handling is difficult. Research into granules that are the safest to use has been conducted around the world for a long time.

The advantage of granules in this application method is that, even though they have low toxicity, with other formulations such as powders, the sprayer is exposed to considerable exposure to the sprayed chemicals, whereas in the case of granules, First of all, there is almost no danger, and currently in Japan, the main pesticides for paddy fields are powders, but since they use equipment such as pipe dusters, they have the disadvantage of not being able to do it alone when spraying. In contrast, granules can be applied by one person. An even bigger problem is when insecticides containing silkworm toxins are applied.

For such insecticides, this method of application using granules with little scattering is extremely advantageous. From this point of view, application in granules can be said to be a realistic and effective method of using insecticides even if they have an effect on other useful organisms.

In order to apply insecticidal granules to the water surface to control aquatic pests and pests that have a life cycle near water, it is important to find out how to effectively disperse the active ingredients into the water. In particular, when a poorly water-soluble active ingredient is made into granules for water surface application, how to release the active ingredient into water becomes a major problem.

Regarding granules for water surface application, methods include impregnating the grain core with emulsion and gradually releasing it into water, or diffusing it into water together with a carrier that has swelling properties and affinity for water, but both methods are sufficient. This is thought to be due to strong adsorption of the active ingredient to the soil, and a sufficient control effect cannot be obtained unless a larger amount than necessary is used.

From this point of view, research has been carried out on granulation, which utilizes active ingredients more efficiently. However, all of these methods have advantages and disadvantages, and they have not been put to practical use in reality.For example, methods such as foaming obsidian or making the granules float by holding the active ingredient in a light carrier that floats on water (
Special Publication No. 48-1181, 4T-1240, 48-1
No. 182, No. 44-8600, JP-A-55-13930
No. 8, No. 58-65203) is a method in which active ingredients are held in plastic granules with a specific gravity of 1 or less, and the granules themselves float (specially Publication No. 45-9560, 48-118
No. 0, No. 49-24222, JP-A-55-139308
However, the carrier is expensive and is made of a material that is difficult to biodegrade, which is a concern in terms of pollution. A method of coating a solid sedimentary substance with an active ingredient and a floating substance such as a waxy substance, plastic, or inorganic foam to suspend the active ingredient in water (Japanese Patent Publication No. 15613/1983, 58-26882)
Although the above-mentioned drawbacks are covered, the active ingredients are incorporated into plastics, waxy substances, inorganic foams, etc. used as floating substances, and the active ingredients are eluted from these materials. There are some drawbacks that are difficult to overcome. A method in which the active ingredient is suspended together with a film-forming substance retaining air when a water-soluble carrier is dissolved (Japanese Patent Laid-Open No. 60-142
No. 901) has the disadvantage that the active ingredient that has floated to the surface is held within the film and is blown away by the calm, resulting in a failure to apply it uniformly. Carbonates of alkali metals or alkaline earth metals and solid acids are used as part of the granules, and these react in water to generate carbon dioxide gas, which causes the granules to float and spread the active ingredients on the water surface. The method (Japanese Patent Publication No. 47-27930) does not allow carbon dioxide gas to be gradually generated due to moisture in the atmosphere during storage, and because solid acids are used, the activity is chemically unstable on the acidic side. The ingredients have drawbacks that make them inapplicable.

[Problem to be solved by the invention]

An object of the present invention is to provide granules for water surface application that effectively disperse in water an insecticidal active ingredient that is sparingly soluble or insoluble in water.

[Means and effects for solving the problems] The present inventors have solved the above problems (after various studies, they have succeeded in preparing granules for water surface application, which could not be expected from conventional known techniques, The invention has been completed.

That is, the present invention comprises (al solid carrier, (bl slightly water-soluble or water-insoluble insecticidal active ingredient, and fc) a high boiling point solvent that is poorly soluble or water-insoluble in water and has a specific gravity of less than 1. This is a water surface application school regulation for agricultural chemicals that is characterized by containing.

The present invention is to hold an insecticidal active ingredient in a carrier together with a high boiling point solvent, but in terms of utilizing floating substances, it is
This is similar to the technology described in Japanese Patent No. 26882.

However, in the technique described in Japanese Patent Publication No. 48-15613, polyurethane, polyethylene, perlite, etc. are used as floating substances, and in the latter case, waxy substances such as paraffin, stearic acid, rosin, and Japanese wax are used. On the other hand, the present invention is completely different in that the high boiling point solvent itself is used as the buoyant Th prize. In addition, in that water-soluble carriers can be used,
There is Publication No. 901, but the former uses a waxy substance to float as described above, and the latter makes a film-forming substance hold air and float due to its buoyancy. It is essentially different from granules that are suspended by utilizing the specific gravity of poorly soluble solvents. In other words, in the case of the former granule, when the granule is submerged in water, the material of the granule core is dissolved or dispersed in the water by the water that has penetrated from the coarse part of the waxy substance held heterogeneously on the surface of the granule nucleus. As a result, the kernels are lost and a shell of waxy material containing the active ingredient floats on the water surface. The latter also has a similar behavior in water, and once the granules are submerged in water, the granule cores are lost and an air-retaining film floats on the water surface together with the active ingredient. It is clear that a high boiling point solvent containing an active ingredient with a specific gravity less than 1, which is poorly soluble in water, separates from the carrier and floats on the water surface in water.

The water surface application granules for agricultural chemicals according to the present invention are granules prepared by holding an insecticidal active ingredient and a high boiling point solvent in a carrier. The high boiling point solvent referred to herein is required to have a specific gravity less than 1 and low water solubility. Its water solubility is
The solvent should have a pH of about 1,100 pp or less, but more preferably about 20 ppH or less, and should also have the property of sufficiently dissolving the insecticidal active ingredient.In the present invention, the properties of the solvent are important. It has its characteristics here. Specifically, isophorone and glycol ethers such as ethylene glycol monobutyl ether and diethylene glycol mobutyl ether have a specific gravity less than 1, but their water solubility is too high and therefore unsuitable.

Of course, ethylene glycol monophenyl ether and the like have a specific gravity greater than 1 and a high water solubility, making them unsuitable. Furthermore, phthalic acid alkyl esters, which are high boiling point solvents known as plasticizers, generally have extremely low water solubility, except for some lower alkyl esters. Therefore, the solvent can be selected depending on its specific gravity. That is, among phthalic acid alkyl esters, di-2-ethylhexyl phthalate is selected based on its specific gravity. Other alkyl esters such as adipic acid, maleic acid, fumaric acid, and sebacic acid have relatively low specific gravity, so they must be selected based on water solubility. In this sense, di-2-ethylhexyl ester derivatives satisfy this condition for most acids. The most suitable high-boiling point solvents include the following solvents with a specific gravity of less than 1 (low solubility in water), such as n-butyl laurate, di-2-ethylhexyl adipate, di-2-ethylhexyl maleate, Examples include di-2-ethylhexyl sebacate, di-2-ethylhexyl phthalate, di-n-octyl phthalate, but of course, the present invention is not limited to these as long as it is a high boiling point solvent that satisfies the above conditions. The characteristics of the granules are that when the carrier is dissolved or dispersed in water, the insecticidal active ingredient is dissolved together with the solvent.
By floating due to the low specific gravity of the solvent, the active substance is effectively dispersed in water and can be used effectively. Therefore, depending on the type of surfactant, the addition of surfactants may destroy the buoyancy of the solvent containing the active ingredient.
The expected insecticidal effect may not be obtained. However, depending on the type of surfactant, there are some that can actually enhance the effect.

It is a surfactant that has a specific gravity less than 1 and also has the property of spreading on the water surface.

The use of such surfactants poses no problem in the present invention.

The amount of solvent relative to the amount of active ingredient basically does not matter as long as the specific gravity of the active ingredient mixture is less than 1, but the effect of the solubility of the active ingredient in the solvent must be taken into account. Regarding the amount of solvent added Although it varies depending on the type of carrier used, it is usually used in an amount of 1 to 15% by weight based on the granules.

The insecticidal active ingredient that can be used in the present invention preferably has low water solubility. Since it is required to float with the solvent as mentioned above, its water solubility should be equal to or lower than that of the solvent used; however, the specific gravity of the insecticidal active ingredient need not be less than 1. (It is important that the specific gravity of the mixed solution of the solvent and the active ingredient is lighter than 1. If an active ingredient with a specific gravity heavier than 1 is used, the amount may be adjusted by adjusting the amount of the solvent.

Next, the solid carrier used in the granules according to the present invention may be water-soluble or water-dispersible, or even water-insoluble. Examples include potassium chloride, sodium chloride, sodium sulfate, ammonium sulfate, ammonium chloride, ammonium nitrate, urea, boron, sugar, and water-soluble polymers. Examples of water-dispersible carriers include clay, talc, calcium carbonate, diatomaceous earth, white carbon, bentonite, starch, and glass powder, and examples of water-insoluble carriers include river sand and brick pieces. These carriers may be used alone or in combination (but are not limited to these).

One method for preparing the granules of the present invention is to prepare or prepare granule cores in advance and coat them with a liquid material in which an insecticidal active ingredient is dissolved in a high boiling point solvent. The method of coating is
Conventional coating methods such as mixing or spraying a high-boiling solvent containing the active ingredient with the granule cores may be used; alternatively, the insecticidal active ingredient and the solvent may be mixed together when preparing the granule cores. ,
A method of granulating it into granules may also be used. As a method for preparing grain nuclei, the carrier may be used as it is, or it may be prepared by pulverization to a desired size, or in some cases, water-soluble or water-dispersible additives may be used. Granules are granulated to a desired size using excipients to form granule cores. Excipients include gums, dextrin, carboxymethyl cellulose, sodium alginate, starch, polyvinyl alcohol, and the like. The amount of excipient depends on the type of carrier used, but may be any amount necessary to form granule nuclei.Usually, 1 to 141% of the granule is used.

The micro-granule formulation is most suitable for controlling harmful pests that live near the water surface, such as the rice water weevil, the brown planthopper, the brown planthopper, the black leafhopper, and the black-spotted planthopper.

Further, the granules according to the present invention can also be used as mixed granules. At this time, there is no problem even if only one active ingredient requires the characteristics of the granule according to the present invention, or both active ingredients require the characteristics of the granule according to the present invention. The granules according to the present invention can be similarly applied to mixed granules with fungicides or herbicides.

〔Example〕

Next, Examples and Test Examples will be shown, but the present invention is not limited thereto.

Example 1 98 parts by weight of potassium chloride and 2 parts by weight of Celogen PR (manufactured by Daiichi Kogyo Seiyaku ■) were pulverized and mixed, water was added, granulated, and dried.
One part of 10 grain nuclei was obtained. To 96 parts by weight of this grain nucleus, 2-(
4-Ethoxyphenyl)-2-methylpropyl 3-phenoxybenzyl ether (hereinafter referred to as ethofenpro7x) was dissolved in 3.2 parts by weight of 2-ethylhexyl adipate. 100 parts by weight of granules containing 0.8% Fenbrox were obtained.

Example 2 96 parts by weight of a mixture of clay and talc (mixing ratio -7:3) and 2 parts by weight of Celogen 3H (manufactured by Daiichi Kogyo Seiyaku ■) were pulverized and mixed, water was added, granulated, and dried to obtain 100 parts by weight of grain nuclei. I got the department.

0.8 parts by weight of etofenprosox was added to 96 parts by weight of the granules and di-2-ethyl adipate 6 hexyl 3
．． A liquid substance dissolved in 2 parts by weight was impregnated to obtain 100 parts by weight of granules containing 0.8% of etofenpro-7x.

Example 3 88 parts by weight of potassium chloride, 10 parts by weight of sodium chloride, and 2 parts by weight of Agrigam PG-0720 (manufactured by Daiichi Kogyo Seiyaku ■) were pulverized and mixed, then water was added, granulated, and dried to obtain 100 parts by weight of grain nuclei. Obtained. 97 parts by weight of the grain kernels were impregnated with a liquid prepared by dissolving 0.5 parts by weight of ethofenbrox in 2.5 parts by weight of lauric an-butyl.
．． 100 parts by weight of granules containing 59'6 were obtained.

Example 4 47 parts by weight of potassium chloride, 47 parts by weight of clay, 2 parts by weight of Celogen PR (Daiichi Kogyo Seiyaku ■1, 2 parts by weight of phthalate)
3.5 parts by weight of ethylhexyl and 0.5 parts by weight of ethofenbrox are ground and mixed, added with water, granulated, and dried.
Granules containing 0.5% etofenbrox 1ooiit
I got the department.

Example 5 94 parts by weight of potassium chloride, 2 parts by weight of Celogen PR (manufactured by Daiichi Kogyo Seiyaku ■), 3 parts by weight of di-2-ethylhexyl adipate
．． Etofenpro 7
100 parts by weight of granules containing 0.5% of sugar were obtained.

Example 6 97 parts by weight of borax was impregnated with a liquid obtained by dissolving 0.5 parts by weight of etofenbrox in 2.5 parts by weight of di-2-ethylhexyl sebacate, and 0.5 parts by weight of etofenpro7
One part of granules containing 10% was obtained.

Example 7 Potassium chloride was made into granules using a preget machine, and 97 parts by weight of the granules were mixed with 0.5 parts by weight of ethofenbrofux and 2.5 parts by weight of di-2-ethylhexyl adipate. 8M and impregnated with this liquid to obtain 100 parts by weight of granules containing 0.5% etofenebrox.

Example 8 95.5 parts by weight of river sand and 0.5 parts by weight of etofenbrox
Granules 100 containing 0.5% etofenbrox were prepared by mixing 1.5 parts by weight of diatomaceous with a liquid obtained by dissolving 2.5 parts by weight of di-2-ethylhexyl adipate.
Parts by weight were obtained.

Example 9 A liquid prepared by dissolving 95.5 parts by weight of granular calcium carbonate and 0.5 parts by weight of etofenebrox in 2.5 parts by weight of di-2-ethylhexyl adipate was mixed with 1.5 parts by weight of white carbon. , 100 parts by weight of granules were obtained.

Example 10 98 parts by weight of potassium chloride and 2 parts by weight of Celogen PR (manufactured by Daiichi Kogyo Seiyaku ■) were pulverized and mixed, water was added, granulated, and dried.
100 parts by weight of grain nuclei were obtained. In 95.8 parts by weight of this grain nucleus,
Etofuenbrox 0.5 parts by weight and Tsurupol 315
3 (Surfactant manufactured by Toho Chemical Co., Ltd.) 0.2 parts by weight dissolved in 3.5 parts by weight of di-2-ethylhexyl adipate was impregnated with 100 parts by weight of granules containing 0.5% etofenbrox. I got it.

Comparative Example 1 98 parts by weight of potassium chloride and 2 parts by weight of Celogen PR (manufactured by Daiichi Kogyo Seiyaku ■) were pulverized and mixed, water was added, granulated, and dried.
One part of 10 grain nuclei was obtained. 96 parts by weight of the granules were impregnated with a liquid solution prepared by dissolving 0.8 parts by weight of etofenprosox in 3.2 parts by weight of ethylene glycol monobutyl ether, and 100 parts by weight of granules containing 0.8% etofenbrox were added. Obtained. The solvent ethylene glycol motsubutyl ether used in this test has a specific gravity less than 1, but has high water solubility.

Comparative Example 2 96 parts by weight of granules prepared in the same manner as in Comparative Example 1 were impregnated with a liquid solution prepared by dissolving 0.8 parts by weight of Ethofenebrox in 3.2 parts by weight of dibutyl phthalate. Dibutyl phthalate, the solvent used in the test to obtain 100 parts by weight of granules containing 1%, has a low water solubility but a specific gravity of 1 or more.

Comparative Example 3 To 96 parts by weight of grain nuclei prepared in the same manner as in Comparative Example 1, 0.8 parts by weight of etofenbrox and Hytenol NF-1 were added.
Granules 10 containing 0.8% etofenebrox were impregnated with a liquid obtained by dissolving 0.1 part by weight of 3 (manufactured by Daiichi Kogyo Seiyaku ■) in 3.1 parts by weight of di-2-ethylhexyl adipate.
Hitenol NF-1 used in the 0-piece test in which 1 piece of cap was obtained
3 is a nonionic surfactant.

In the examples and comparative examples, etofenbrox [2-(4-ethoxyphenyl)-2-methylpropyl 3-phenoxybenzyl ether] is used as the insecticidal active ingredient, but the present invention is limited to these. Similarly, compounds with low water solubility can be used in the granules of the present invention.

Next, examples of mixed granules will be shown.

Example 11. Mixed granules with insecticide 911 parts of potassium chloride, 4 parts of S,S''-2-dimethylaminotrimethylene bis(thiocarbamate) and 2 parts by weight of Celogen PR (manufactured by Dai-Nigyo N■) were ground. They were mixed, added with water, granulated, and dried to obtain 96 parts by weight of a base.In this base, 20.8 parts by weight of ethofen block was dissolved in 3.2 parts by weight of di-2-ethylhexyl adipate. 100 parts by weight of mixed granules were obtained.The insecticide S, S''-2-dimethylaminotrimethylene bis(thiocarbamate) used in this test was cloth plated as badan granules.

Example 12. Mixed granules with bactericide Potassium chloride 87.2 parts by weight, Etofen block 20
．． 8 parts by weight, 2 parts by weight of di-2-ethylhexyl adipate, 8 parts by weight of 3-allyloxy-1,2-benzisothiazole-1,1-dioxide as a bactericide, and 2 parts by weight of Celogen PR (manufactured by Daiichi Kogyo Seiyaku ■). The fungicide used in this test was Oryzemate, which was used as a water surface application agent against rice blast disease. It is commercially available under the name of ``Kanjiri''.

Test example 1. Paddy rice was planted in resin pots with a density of 1/10,000 are and flooded with water.
Here, 2 kg of granules prepared according to Example 1.11.12 and Comparative Examples 1 to 3 were applied to the water surface per 10 ares,
The pot was covered with a wire mesh cylinder over a period of time, and 20 female adult brown planthoppers were released into the pot. After 24 hours, the number of dead insects was counted to determine the mortality rate. The test results are shown in Table-1.

Table-1 Test example 2. Insecticide test test example 1 against black leafhopper
Adult female leafhoppers were released into pots prepared in the same manner as above, and the number of dead insects was counted to determine the mortality rate. The test results are shown in Table-2.

Table-2 Test example 3. Control test for N blast The application timing was 1, 4, and 6 days before inoculation with rice blast fungus. The control effect was determined by counting the number of lesions on the leaves one week after inoculation with the blast fungus. The test was performed in 5 replicates. The results are shown in Table 3, where the numbers indicate the average values for each area.

Table-3 11: Oryzemate granules (active ingredient-3-allyloxy-
1,2-benzisothiazole-1,1-dioxide) This test example is a test of the influence on the effect of other agents in mixed granules with other agents.

The granules tested were mixed granules with a rice blast killer and occlusive agent, and it was clear that they had no effect on the pesticidal effect as a fungicide.

〔Effect of the invention〕

If the granules of the present invention are used, as is clear from the results of the test examples, the effect of the insecticidal active ingredient, which is Bit soluble in water and has strong soil adsorption properties, can be effectively exerted when applied to the water surface. Harmful pests that can be targeted include, but are not limited to, the brown planthopper, the brown planthopper, the brown leafhopper, and the brown flycatcher.

Insecticidal active ingredients sometimes have an effect on other insects, but for example, the use of insecticidal active ingredients that are highly toxic to silkworms, bees, etc. is limited. However, the granules of the present invention have almost no effect on these beneficial insects, and the agriculturally useful insecticidal active ingredients can be sufficiently used.

Furthermore, the granules for water surface application of the present invention can also be mixed with other agricultural chemicals. In other words, mixed granules with pesticides and the like that can be applied to water surfaces to enhance their control effects can also be used as a mixture without reducing the effects of each other.

Claims (1)

[Scope of Claims] 1) (a) a solid carrier; (b) an insecticidal active ingredient that is sparingly soluble or insoluble in water; and (c) an insecticidal active ingredient that is sparingly soluble or insoluble in water and has a specific gravity of less than 1. Granules for water surface application for agricultural chemicals, characterized by containing a light high boiling point solvent. 2) The water surface application granules for agricultural chemicals according to claim 1, wherein the solid carrier is a water-soluble carrier. 3) The insecticidal active ingredient is 2-(4-ethoxyphenyl)-
The water surface application granule for agricultural chemicals according to claim 1, which is 2-methylpropyl 3-phenoxybenzyl ether.