JPH115704A - Coated agrochemical granule and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain coated agrochemical granules capable of controlling release or elution of an agriculturally active ingredient by coating slightly soluble agrochemical granules with a resin coat consisting essentially of a thermosetting resin. SOLUTION: The surfaces of granules in which one or more kinds of a slightly soluble agriculturally active ingredient (e.g. 2-isopropoxyphenyl- Nmethylcarbamate) and one or more kinds of agrochemical carrier substance are compounded are coated with a coating material comprising a thermosetting resin (e.g. amide resin) and as necessary, wax-like substance (e.g. candelilla wax). The coating amount of the wax-like substance is preferably 0.001-40 wt.% based on the thermosetting resin. The coating ratio b×100/(a+b) [(a) is weight of uncoated agrochemical granules; (b) is weight of coating film]} of the coating material is preferably 5-30% from the viewpoint of elution control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a coated pesticide granule and a method for producing the same. Specifically, a pesticide granule coated with a coating material mainly composed of a thermosetting resin to control the release or dissolution (hereinafter, referred to as dissolution) of the poorly water-soluble pesticide active ingredient, and It relates to the manufacturing method. The coated pesticide granules of the present invention are particularly effective when used as herbicides.

[0002]

2. Description of the Related Art In recent agricultural environments in which the number of farmers is decreasing and the population is aging, labor saving in crop cultivation management has long been said to be urgent. Pest control, one of the most important tasks in cultivation management, can be broadly classified into cases where the target is a pest and a case of a weed. The current situation is that a control system is formed by spraying and applying several times. Agricultural spraying requires a lot of effort because of the frequency and variety of chemicals,
For example, in the case of paddy rice, an agent used for seed disinfection during seeding and germination, an agent for seedling blight, rice cultivation disease from seedling raising to young panicle formation stage to ear setting stage, rice weevil, leafhopper, planthopper, sheath blight, stink bug, etc. There are various chemicals for spraying, and weeds are sprayed with herbicides such as those for barnyard grass and broadleaf weeds.
It is currently applied. As described above, the types and the number of times of the control work are extremely large, which is an obstacle to constructing a labor-saving cultivation system.

[0003] Under such circumstances, the present inventors can only apply and apply various pesticides several times during the cultivation period, once at the time of sowing or at the time of transplanting seedlings. The control method was considered to be the ideal labor-saving control method when using chemicals. For this purpose, pesticide granules that have the function of dissolving pesticide active ingredients for the first time at the appropriate time when different types of pesticides are not eluted until necessary, is necessary. In other words, the period during which dissolution is suppressed for a certain period of time after application (hereinafter referred to as the “elution suppression period”), and the period after the elapse of a certain period from the start to the end of the dissolution of the pesticide active ingredient (hereinafter, the component elution period ), And a pesticide granule having a timed dissolution function and a so-called sustained release function is required.

Until now, the function of sustained release of pesticides has been performed by granulating the pesticides into granules. As a method for producing pesticide granules, generally, (1) a pesticide active ingredient, a binder and various auxiliary agents are added to mineral fine powder, kneaded with water, extruded from pores, cut, and dried. (2) impregnation method of impregnating inactive granules made of mineral substances etc. with liquid pesticide active ingredient, (3) inactive granules made of mineral substances etc. There are known three types of production methods, a coating method in which a pesticidal active ingredient is adhered to a surface with a binder, and the above method is appropriately selected depending on the field of use. However, in these pesticide granules, the pesticidal active ingredient is eluted in a short period of time. Therefore, it is impossible to establish the above-described ideal labor-saving control method due to the occurrence of phytotoxicity during application in such a method.

[0005] As a pesticide in which the active ingredient of a pesticide is controlled by a film, a coated granular pesticide whose release is gradually released by a thermoplastic resin film (Japanese Patent Publication No. 64-5002) has been proposed. In terms of sustained release, higher control than the above-mentioned conventional technology can be performed, but the timed dissolution function has not been achieved, and further, it is limited to easily water-soluble pesticide active ingredients, and the application range of the pesticide active ingredients is small. Things. In recent years, a coated pesticide granule in which a pesticide granule is coated with a multilayer coating composed of a highly water-swellable substance layer and an olefin polymer layer (Japanese Patent Application Laid-Open No. 6-9303), an alkali substance layer, an olefin resin and an alkaline water Coated pesticide granules obtained by coating pesticide granules with a multilayer coating comprising a mixture layer with a soluble polymer (Japanese Patent Application Laid-Open No. 6-9304), a mixture layer of an alkali substance layer, a condensation polymer and an alkali water-soluble polymer Coated pesticide obtained by coating a pesticide granule with a multi-layer coating (JP-A-6-72805), coated pesticide coated with a pesticide granule by a multi-layer coating consisting of a highly water-swellable substance layer and a condensation polymer layer Granules (Japanese Unexamined Patent Publication No.
No. 80514) has been proposed, but in practice, unless the active ingredient is a highly water-soluble agricultural chemical active ingredient, there is a possibility that the elution amount showing a medicinal effect cannot be secured while the agricultural chemical active ingredient remains in the core material inside the coating. In addition, since these coated pesticide granules are all coated with a thermoplastic resin, their dissolution function,
In particular, the elution suppression period tends to be long. Those having such characteristics are particularly effective when used for the purpose of sterilization, but have the problem that they cannot be used for applications requiring a dissolution inhibition period of several days.

[0006]

DISCLOSURE OF THE INVENTION The present inventors have intensively studied a coated pesticide granule in which the above-mentioned problems have been solved. As a result, it has been found that coating a poorly water-soluble pesticide granule with a thermosetting resin as the main component of the resin film results in a coated pesticide granule capable of advanced elution control. Completed the invention. As is apparent from the above description, an object of the present invention is to use a coating material containing a thermosetting resin as a main component and to select a processing method suitable for each of the coating materials to provide an advanced elution control function. The object of the present invention is to provide a coated pesticide granule having:

[0007]

The present invention provides the following (1) to
This is indicated by (10). (1) A pesticide granule in which at least one or more poorly water-soluble pesticide active ingredients are coated with a resin coating mainly composed of a thermosetting resin. (2) a resin film whose main component is a thermosetting resin;
2. The coated pesticide granule according to the above item 1, wherein the coated pesticide granule is a two- or more-layer coating comprising a coating containing a waxy substance as a main component. (3) The coated agricultural chemical granule according to any one of the above (1) or (2), wherein the thermosetting resin is a reaction product of an acid component and an amine component. (4) The coated pesticide granule according to any one of the above (1) or (2), wherein the thermosetting resin is a thermally modified alkyd resin. (5) The coated agricultural chemical granule according to any one of the above (1) or (2), wherein the thermosetting resin is a reaction product of a polyester component having an active terminal group and a polyisocyanate.

(6) A thermosetting resin is mainly added to the pesticide granule while flowing or tumbling the pesticide granule having an average particle diameter of 0.5 mm or more containing at least one or more poorly water-soluble pesticide active ingredients. Spray or drip coating material as a component,
A method for producing coated pesticide granules, comprising forming a cured film on the surface of the pesticide granules. (7) The surface of the coated pesticide granule obtained by the production method according to the above (6) is further coated by spraying or dropping a coating material containing a waxy substance as a main component. A method for producing pesticide granules coated with at least two layers. (8) The method for producing a coated agricultural chemical granule according to any one of the above (6) or (7), wherein the thermosetting resin is a reaction product of an acid component and an amine component. (9) The method for producing a coated pesticide granule according to any one of the above (6) or (7), wherein the thermosetting resin is a thermally modified alkyd resin. (10) The method for producing a coated pesticide granule according to any one of the above (6) or (7), wherein the thermosetting resin is a reaction product of a polyester component having an active terminal group and a polyisocyanate.

An embodiment of the present invention will be described in detail below. The coated pesticide granule of the present invention is a granule comprising one or more poorly water-soluble pesticidal active ingredients and one or more pesticide carrier substances, the surface of which is coated with a coating material. It is composed of a granular core composed of a component and a pesticide carrier substance, a thermosetting resin coating mainly composed of a thermosetting resin as a coating material, and, if necessary, a coating of a waxy substance.

The thermosetting resin film can easily produce various types of resin films by selecting the type of thermosetting resin at the time of film formation, and does not require the use of an organic solvent. In some cases, a waxy substance may be coated on the surface or the inner surface of the thermosetting resin layer for the purpose of imparting timed dissolution. Thereby, the wax-like substance fills the fine pores and the core of the pesticide granule serving as nuclei on the surface of the thermosetting resin film, so that the water resistance of the whole coating film can be increased. Also, various auxiliary components different from the brazing component can be added and dispersed. The dissolution rate can be adjusted by the type and amount of addition, and the dissolution of the pesticidal active ingredient can be started after a certain period. Further, by increasing or decreasing the amount of the auxiliary component added, the period up to the start of elution can be adjusted.

The term "timed dissolution" as used in the present invention means the ability to suppress dissolution for a certain period of time after application to a field and to dissolve quickly after a certain period. The time-dissolved coated pesticide granule is composed of a period during which dissolution is suppressed for a certain period after application to a field (elution suppression period) and a period from the start to the end of dissolution (component dissolution period). The timed elution function of the present invention comprises an elution inhibition period and a component elution period, and specifically, an elution inhibition period from application to a field until 10% by weight of the pesticidal active ingredient in the coating is eluted. And a component elution period of more than 10% by weight and up to 90% by weight, and the ratio of the elution suppression period / the component elution period can be specified to be 0.1 or more.

The thermosetting resin used in the present invention is not particularly limited, but includes thermosetting resins such as amide resin, imide resin, alkyd resin, urethane resin, urea resin, epoxy resin, and acrylic resin. it can. Of these, amide resins, imide resins, alkyd resins, and urethane resins are preferred. The thermosetting resin suitably used in the present invention, that is, an amide resin or an imide resin obtained by a reaction between an acid component and an amine component will be described in detail. Here, the acid component refers to a compound of an acid anhydride having two or more functions, a polyfunctional acid and an acid ester.
The polyfunctional acid may be a functional group such as an amino group or a hydroxyl group other than the carboxyl group. The acid ester is industrially preferably an ester of an acid and methanol or ethanol, and most preferably an acid anhydride having high activity in consideration of reactivity.

The amine component is not particularly limited, and refers to a compound having a bifunctional or higher functional amino group. Of these, a diamine is industrially preferable. Further, a resin having a structure in which an ether group is introduced into an acid component or an amine component for the purpose of imparting flexibility of the resin may be used. Products obtained by the reaction of these acid components and amine components include polyamides,
Examples include amide resins and imide resins such as polyimide, bismaleimide, polyamide imide, polyether imide, maleimide, and polyether amide. The reaction product of the acid component and the amine component can be used directly or in the form of a solution. As the solvent that can be used at this time, at least one kind may be selected from N-methyl-2-pyrrolidone, dimethylacetamide, dimethylfromamide, ethyl carbitol, butyl cellosolve, and the like. In addition, an acid component or an amine component having a monofunctional group can be added to control the molecular weight. Further, a siloxane compound having an active terminal having one or more functional groups may be added to the acid component and the amine component for the purpose of imparting hydrophobicity.

In addition, specific urethane resins and heat-modified alkyd resins are suitable as materials that can be used without a solvent. The specific urethane resin is a reaction product of a polyester component having an active terminal group and a polyisocyanate. The polyester having an active terminal group is a chain polyester compound having a hydroxyl group or a carboxyl group at the terminal group. The polyester compound having an active terminal group used in the present invention has a molecular weight of 200 to 8,000, preferably 50 to 8,000.
It is a liquid material of 0 to 3000, and an aliphatic polyester having a bifunctional group at both ends is most suitable to satisfy this. If the molecular weight exceeds the upper limit of 8000, the viscosity becomes high and it is difficult to react with the polyisocyanate. Also,
If the molecular weight is less than the lower limit of 200, after the reaction with the polyisocyanate, there are too many urethane bonds and the coating becomes brittle.
As the polyisocyanate, a commercially available product may be used. It is more effective to add a trifunctional or higher carboxylic acid compound and / or hydroxycarboxylic acid compound in order to enhance the curability.

Examples of the curing agent used include polyols such as pentaerythritol, glycerin, 1,4-butanediol, and diamines such as 1-butyl-2-ethyl-1,3-propanediol, and polyisocyanates.
Further, a solvent such as toluene or xylene can be used as needed.

The heat-modified alkyd resin includes phthalic anhydride,
Polybasic acids such as maleic anhydride and pentaerythritol,
It is a general heat-modified alkyd resin obtained by heating and condensing a polyhydric alcohol such as glycerin and a natural vegetable oil or a vegetable fat or a natural animal oil as a denaturant, and the type thereof is not particularly limited. Examples of the natural vegetable oil or vegetable fat include soybean oil, linseed oil, tung oil, surfflower oil, palm oil, palm oil, and the like, and examples of the natural animal fat include beef tallow.

The thermally modified alkyd resin has a molecular weight of 500
5,000 to 5,000 are preferably used. Molecular weight 500
Those below the lower limit of the above, the strength of the resin film generated by the reaction with the unsaturated oil is small, and the curing and drying speed is low,
Those exceeding the upper limit of 5000 have higher viscosity,
It becomes difficult to coat pesticide granules. Examples of the unsaturated oil having a conjugated double bond in the molecule include tung oil, dehydrated castor oil, and the like. The tung oil is mainly composed of eleosteric acid having a conjugated double bond. Dehydrated castor oil is rich in 9,11 linoleic acid having a conjugated double bond. These unsaturated oils have the effect of diluting the alkyd resin and lowering the viscosity, as well as cross-linking with the unsaturated oil or the alkyd resin in the presence of the metal soap itself to form a resin (solidify).

When a wax-like substance is used, the wax-like substance is a substance having a solid or semi-solid alkyl group at room temperature, and a substance melting at a temperature in the range of 40 ° C. to 130 ° C. is easy to handle. preferable. Examples of the waxy substance include, for example, vegetable waxes such as candelilla wax, carnauba wax, rice wax, wood wax, jojoba oil, beeswax, lanolin, animal waxes such as whale wax, montan wax, ozokerite, Mineral wax such as ceresin, paraffin wax, microcrystalline wax, petroleum wax such as betrolatam,
Synthetic hydrocarbons such as Fischer-Tropsch wax and polyethylene wax, modified waxes such as montan wax derivatives, paraffin wax derivatives and microcrystalline wax derivatives, hydrogenated waxes such as hardened castor oil and hardened castor oil derivatives, 12-hydroxystearic acid, stearic acid Examples include fatty acids such as amides, phthalic anhydrides, chlorinated hydrocarbons, acid amides, esters, ketones, and thermoplastic resins having waxy properties, but are not limited thereto.

The coating amount of the waxy substance is preferably 0.001 to 40% by weight based on the thermosetting resin, and if the coating amount is below the lower limit of 0.001% by weight, the effect of water resistance will be insufficient. If it is not exhibited, and if it exceeds the upper limit of 40% by weight, the film thickness of the whole coating film will be large, resulting in high cost. The method of coating the granules with the waxy substance is not particularly limited, but a method of spraying or dripping the molten waxy substance onto the granules is preferable. Further, an olefin resin may be added to the waxy substance. In this case, the addition of the olefin resin is expected to suppress the dissolution rate, but if the molecular weight is large, the dissolution tends to be extremely suppressed. Therefore, the molecular weight of the olefin resin is preferably 100,000 or less. Further, the addition amount of the olefin-based resin is preferably 0.1 to 20% by weight. If the addition amount is much more than 20% by weight, the film tends to be largely dependent on the temperature, and is less than 0.1% by weight. In this case, there is no point in adding the olefin resin.

A water-insoluble or hardly soluble inorganic fine powder can be added as an auxiliary component to the coating material. By increasing or decreasing the addition amount of the fine powder, a thermosetting resin which is a main component of the coating material can be saved, which is advantageous in cost. Examples of these fine powders include bentonite, talc, clay, metal oxides, siliceous materials, carbonates and sulfates of glass and alkaline earth metals. The water-insoluble or sparingly soluble inorganic fine powder has a particle size of 1 μm or more and 50 μm or more.
μm or less, and preferably 20 μm or less. These particle sizes may be determined in consideration of the thickness of the coating, and it is preferable that the particles are uniformly distributed in the coating from the viewpoint of complete coating. The amount of addition is not particularly limited, but is preferably 50% by weight or more and 90% by weight or less in terms of the content in the coating material because the cost of the coating material is reduced.

In order to prevent distortion of the film after film formation,
An anti-strain agent may be added to the coating material. Normal,
One or more of dipentene, methoxyphenol, cyclohexanone oxime, methyl ethyl ketoxime and the like can be used.

The coated pesticide granules of the present invention are those in which the surface of the pesticide granules containing the poorly water-soluble agricultural chemical active ingredient is coated, and the form of the pesticide granules used is preferably spherical. is there. The particle size is preferably 0.5 to 10 mm, more preferably 0.8 to 5 mm, and may be 10 mm or more. The production method of these granules can be carried out according to a known method, but generally, an extrusion granulation method in which a pesticidal active ingredient and a granulation aid are mixed and then extruded into granules is the simplest method. is there.

As the granulation aid, known substances can be used. In general, mineral carriers, vegetable carriers, slaked lime, urea, ammonium sulfate, salt and salt, chemical fertilizers, plastic foams and the like can be used. It can be added and mixed. Mineral carriers are bentonite, clay, kaolin, sericite, talc, acid clay, pumice, quartz sand, quartzite, calcium carbonate, zeolite, perlite, vermiculite, etc.Vegetable carriers are peach, sawdust, wood flour, pulp Flock,
Soy flour, corn stalk, starch and the like. As a binder used for granulation, gum arabic, carboxymethyl cellulose, hydroxyethyl cellulose, lignin sulfonates, polyvinyl alcohol, polyethylene glycol, surfactants, liquid paraffin, and the like,
Those having high water solubility are preferred.

The poorly water-soluble pesticidal active ingredient used in the present invention is not particularly limited, but mainly has an action of miticide, nematicide, etc. in addition to insecticide, sterilization, weeding, and plant growth regulation. . Furthermore, these include repellents and attractants, and the types thereof can be applied without limitation.

There are no particular restrictions on the type and combination of the poorly water-soluble pesticidal active ingredient. However, if the solubility in water is high, the concentration of the pesticidal active ingredient in the initial stage of dissolution becomes too high, adversely affecting agricultural crops, Is not preferred because of the loss of sustainability. In the present invention, poor water solubility is defined as water-insoluble or has a solubility in water of 5 ° C at 25 ° C.
The solubility is preferably 100 ppm or less, and more preferably 50 ppm or less if the safety against chemical damage is emphasized. Further, depending on the use, there is no problem even if a pesticidal active ingredient belonging to water-insoluble is used.

The poorly water-soluble agrochemical active ingredient is preferably in the form of a solid powder at room temperature. Specific examples of the agrochemical active ingredient which can be used in the present invention are shown below.
It is not limited to these.

For example, 1- (6-chloro-3-pyridylmethyl) -N-nitroimidazolidin-2-ylideneamine, O, O-diethyl-S-2- (ethylthio) ethyl phosphorodithioate, 1,3-bis (Carbamoylthio) -2- (N, N-dimethylamino) propane hydrochloride, 2,3-dihydro-2,2-dimethyl-7-benzo [b] furanyl = N-dibutylaminothio-N-methylcarbamate , (2-isopropyl-4-methylpyrimidyl-6) -diethylthiophosphate, 5-dimethylamino-1,2,3-trithiane oxalate, O, O-
Dipropyl-O-4-methylthiophenyl phosphate, ethyl = N- [2,3-dihydro-2,2-dimethylbenzofuran-7-yloxycarbonyl (methyl)
Aminothio] -N-isopropyl-β-alaninate,
1-naphthyl-N-methyl carbamate, 2-isopropoxyphenyl-N-methyl carbamate,

Diisopropyl-1,3-dithiolane-2
-Ylidene-malonate, 5-methyl-1,2,4-triazolo [3,4-b] benzothiazole, 1,2,2
Sodium salt of 5,6-tetrahydropyrrolo [3,2,1-ij] quinolin-4-one, 3-allyloxy-1,2-benzoisothiazole-1,1-dioxide, 2,4-dichlorophenoxyacetic acid or Dimethylamine salt, ethyl ester. 2-methyl-4-chlorophenoxyacetic acid sodium salt or ethyl, butyl ester; 2-methyl-4-chlorophenoxybutyric acid sodium salt or ethyl ester.

Α- (2-naphthoxy) propionanilide, S-1-methyl-1-phenylethyl piperidine-1-carbothioate, S- (4-chlorobenzyl)
-N, N-diethylthiocarbamate, 5-tert-butyl-3- (2,4-dichloro-5-isopropoxyphenyl) -1,3,4-oxadiazolin-2-one, 2- [4- (2,4-dichlorobenzoyl) -1,
3-dimethylpyrazol-5-yloxy] acetophenone, 4- (2,4-dichlorobenzoyl) -1,3-
Dimethyl-5-pyrazolyl-p-toluenesulfonate, 3-isopropyl-2,1,3-benzo-thiadiazinone- (4) -2,2-dioxide or its sodium salt, 2-chloro-4-ethylamino-6 Isopropylamino-s-triazine, 2-methylthio-4-ethylamino-6- (1,2-dimethylpropylamino)
-S-triazine, 2-methylthio-4,6-bis (ethylamino) -s-triazine, 2-methylthio-4,
6-bis (isopropylamino) -s-triazine, 1
-(Α, α-dimethylbenzyl) -3- (paratolyl)
Urea, methyl = α- (4,6-dimethoxypyrimidine-
2-ylcarbamoylsulfamoyl) -o-toluate, 2-benzothiazol-2-yloxy-N-methylacetanilide, 1- (2-chloroimidazo [1,2
-A] pyridin-3-ylsulfonyl) -3- (4,6
-Dimethoxypyrimidin-2-ylurea, S-benzyl = 1,2-dimethylpropyl (ethyl) thiocarbamate, 2-chloro-N- (3-methoxy-2-thenyl)-
2 ', 6'-dimethylacetanilide and the like can be mentioned.

The method for producing a coated pesticide granule of the present invention comprises coating spherical particles containing a poorly water-soluble pesticidal active ingredient with a resin mainly composed of a thermosetting resin. Without limitation, for example, dip coating,
Spray coating and the like. For the spray coating, the above-mentioned coating material is sprayed on the pesticide granules in a rolling state by a rotating drum or the like or in a flowing state by a jet flow device or the like to coat the surface thereof,
There is a curing method. When a coating material dissolved and dispersed using an organic solvent is used, after the coating is completed, the coating material is dried using air or a dry gas such as nitrogen gas, or naturally evaporated to dryness. In this drying step, the temperature of the drying gas may be from the ambient temperature to the boiling point of the organic solvent, and although it depends on the organic solvent used, it is preferably 20 to 130 ° C, and more preferably 50 to 120 ° C. Moreover, you may carry out under reduced pressure of 500 mmHg or less as needed.

From the viewpoint of elution control, the coating rate of the coating material is preferably 5 to 30% by weight, and if the coating rate is much lower than 5% by weight, the coating amount becomes insufficient and it becomes difficult to control the elution amount. %, The cost increases. Here, the coverage is the weight (a) of the uncoated pesticide granule.
Is the ratio of the weight (b) of the coating to the coated pesticide granules when the sum of the weight of the coating and the weight (b) of the coating is 100% by weight, and is determined by the formula [b × 100 / (a + b)].

When the thermosetting resin is used by dissolving it in an organic solvent, the solution concentration is suitably from 0.1 to 10% by weight, and among them, preferably from 3 to 7% by weight. The coating material solution is applied in a single layer or in multiple layers, depending on the required film thickness, but the organic solvent is dried off immediately after the application of each layer. When coating a solvent-free resin or wax-like substance, the coating can be performed in the same manner, in which case the reaction is not caused, and the liquid is liquefied at a temperature capable of realizing a low viscosity, and then applied. A coating is performed by performing a curing reaction. At the time of coating, if a pesticidal active ingredient which is easily decomposed or evaporated by heat is contained, it must be coated at a relatively low temperature accordingly.

[0033]

Hereinafter, the present invention will be described with reference to Examples.
The present invention is not limited by these examples.
In the following examples, “%” is “% by weight” unless otherwise specified. The coverage is the ratio of the weight (b) of the coating to the coated pesticide granules, where the sum of the weight (a) of the uncoated pesticide granules and the weight (b) of the coating is 100% by weight. b × 100 / (a + b)].

(1) Dissolution test method of coated pesticide granules in water The coated pesticide granules are put into a certain amount of water, immersed in water at a constant water temperature of 25 ° C., and after a certain period of time, the granules are taken out and coated. The pesticide granule and the aqueous solution are separated, and the pesticide active ingredient dissolved in the water is quantified. The concentration of the pesticidal active ingredient in the aqueous solution is measured using a high-performance liquid chromatograph (Waters 486 tunable UV / VIS detector) after elution with acetonitrile after solid phase extraction with a Sep-Pak cartridge (Waters) did.

Example 1 30 parts by weight of bentonite and 55 parts by weight of clay as granulation aids, and 15 parts by weight of 2-benzothiazol-2-yloxy-N-methylacetanilide (purity 90%) as a poorly water-soluble agrochemical active ingredient The mixture was uniformly mixed with a kneader, and water and kneaded. This mixture was extruded and granulated with a screw extrusion granulator (screen diameter 0.8 mmφ),
The granules were sized using a spherical sizing machine. Next, the granulated product was dried at 100 ° C. using a circulating hot air drier and sieved to obtain a pesticide granule having an average particle size of 0.8 to 1.4 mmφ containing 13% of the pesticide active ingredient. . Then, using the spouted bed coating apparatus shown in FIG. 1, 30 parts by weight of a 60% soybean oil-modified alkyd resin, 50 parts by weight of tung oil, 15 parts by weight of conjugated linoleic acid pentaerythritol ester, metal soap 2
A coating material consisting of parts by weight, 1 part by weight of a strain inhibitor and 2 parts by weight of talc was coated under the following coating conditions so as to have a coating rate of 10% by weight. Uncoated pesticide granules: 3 kg Hot air temperature: 85 ± 2 ° C. Hot air volume: 4 m ³ / min Spray flow rate: 0.2 kg / min The coating process starts when the temperature of the flowing pesticide granules reaches a predetermined temperature. After spraying for a predetermined time, drying was performed for a predetermined time to obtain a coated pesticide granule (coated particle 1).

Example 2 A waxy substance shown in Table 1 below was heated and melted to a melting point while flowing the coated particles 1 obtained in accordance with Example 1, and then the waxy substance was sprayed on the coated particles 1. Thus, a coated pesticide granule was prepared in which a coating consisting of a thermosetting resin layer and a wax layer was formed (the wax layer coverage was 5% by weight). The coverage of the wax layer is B × 100 / (A + B), where the weight (A) of the coated particles and the weight (B) of the wax layer.

Example 3 30 parts by weight of bentonite and 55 parts by weight of clay as a granulation aid, and 15 parts by weight of 2-benzothiazol-2-yloxy-N-methylacetanilide (purity 90%) as a poorly water-soluble agrochemical active ingredient Was mixed uniformly with a kneader and kneaded with water. This mixture was extruded and granulated by a screw extrusion granulator (screen diameter: 0.8 mmφ), and sized by a spherical granulator. Next, the granulated product was dried at 100 ° C. using a circulating hot air drier and sieved to obtain a pesticide granule having an average particle size of 0.8 to 1.4 mmφ containing 13% of the pesticide active ingredient. . Then, polyester diol NPH-4
50 (manufactured by Chisso Corporation, hydroxyl value 102 KOH-mg /
g; molecular weight 1000) 300 parts by weight and tolylene diisocyanate 55 parts by weight were mixed until uniform, and a liquid heated to 60 ° C. was prepared. Furthermore, heat to 80 ° C,
2-butyl-2-ethyl-1,3-propanediol 6
Parts by weight and 4 parts by weight of paraphenylenediamine were added, and the mixture was uniformly stirred in a short time. After 3200 parts by weight of the pesticide granule is put into a rotary dish-type rolling machine, it is rotated at 600 r / min, and the above heated liquid is dropped from 6 places at 10 ml / min.
After completion of the dropping, warm air was blown into the rotary dish-type rolling machine so that the particle temperature became 95 ° C., and the mixture was reacted while rotating at 850 r / min for 20 minutes to obtain coated pesticide granules (coated granules). 2).

Example 4 A waxy substance shown in Table 1 below was heated and melted to the melting point while flowing the coated grains 2 obtained in accordance with Example 3, and then the waxy substance was sprayed on the coated grains 2. Then, a coating consisting of a thermosetting resin layer and a wax layer was formed to produce a coated pesticide granule (the wax layer coverage was 5% by weight). The coverage of the wax layer is B × 100 / (A + B), where the weight (A) of the coated particles and the weight (B) of the wax layer.

FIG. 2 shows the results of a dissolution test in water of the coated pesticide granules obtained in Examples 1 to 4. As is clear from FIG. 2, it is understood that the coated pesticide granules obtained in Examples 1 to 4 are all excellent in the function of sustained release of the poorly water-soluble pesticide active ingredient. In particular, the coated pesticide granules obtained in Examples 2 and 4 can be produced without a solvent, and thus have high safety.

Example 5 30 parts by weight of bentonite, 55 parts by weight of clay as a granulation aid, and 15 parts by weight of 2-benzothiazol-2-yloxy-N-methylacetanilide (purity 90%) as a poorly water-soluble agricultural chemical active ingredient Was mixed uniformly with a kneader and kneaded with water. This mixture was extruded and granulated by a screw extrusion granulator (screen diameter: 0.8 mmφ), and sized by a spherical granulator. Next, the granulated product was dried at 100 ° C. using a circulating hot air drier and sieved to obtain a pesticide granule having an average particle size of 0.8 to 1.4 mmφ containing 13% of the pesticide active ingredient. . Then, using a 300 ml four-necked flask,
After adding 100 ml of diethylene glycol dimethyl ether, 18.9 g of α, ω-bis (3-aminopropyl) polydimethylsiloxane was dissolved, and the internal temperature was cooled to 10 ° C. while stirring with a stirrer.
6 g was added and reacted to obtain a thermosetting resin A. The obtained thermosetting resin A was diluted by adding diethylene glycol dimethyl ether so that the dissolution concentration was 5%.
The thermosetting resin A solution is poured into a rotary dish-type rolling machine using the pesticide granules described above and then rotated at 600 r / min, and the above heated liquid is dropped from 6 places at 10 ml / min. . After the completion of the dropping, warm air is blown into the rotary dish-type rolling machine so that the particle temperature becomes 120 ° C., and 850 r for 20 minutes.
The reaction was carried out while rotating at a rate of / min to obtain a coated pesticide granule having a coating material content (coating rate) of 10% after coating (coated granule 3).

Example 6 A waxy substance shown in Table 1 below was heated and melted to a melting point while flowing the coated particles 3 obtained in accordance with Example 5, and then the waxy substance was sprayed on the coated particles 3. Thus, a coated pesticide granule was prepared in which a coating consisting of a thermosetting resin layer and a wax layer was formed (the wax layer coverage was 5% by weight). The coverage of the wax layer is B × 100 / (A + B), where the weight (A) of the coated particles and the weight (B) of the wax layer.

Example 7 30 parts by weight of bentonite as a granulation aid, 55 parts by weight of clay, and 15 parts by weight of 2-benzothiazol-2-yloxy-N-methylacetanilide (purity 90%) as a poorly water-soluble agricultural chemical active ingredient Was mixed uniformly with a kneader and kneaded with water. This mixture was extruded and granulated by a screw extrusion granulator (screen diameter: 0.8 mmφ), and sized by a spherical granulator. Next, the granulated product was dried at 120 ° C. using a hot air circulating drier and sieved to obtain a pesticide granule having an average particle size of 0.8 to 1.4 mmφ containing 13% of a pesticide active ingredient. . Then, using a 300 ml four-necked flask,
After putting 100 ml of N, N-dimethylacetamide,
After 4.7 g of p-aminobenzoic acid was dissolved and the internal temperature was cooled to 7 ° C. while stirring with a stirrer, 18.9 g of benzophenonetetracarboxylic dianhydride was added and reacted to obtain a thermosetting resin B. . The obtained thermosetting resin B was diluted by adding diethylene dimethyl ether so that the dissolution concentration was 5%. The above-mentioned pesticide granule is added to the solution, and the solution is put into a rotary dish-type rolling machine, then rotated at 600 r / min, and the above-mentioned heated liquid is dropped from 6 places at 10 ml / min.
After completion of the dropping, hot air is blown into the rotary dish-type rolling machine so that the particle temperature becomes 120 ° C., and the mixture is reacted while rotating at 850 r / min for 20 minutes, so that the coating material content after coating (coating rate) ) To give a coated pesticide granule of 10% (coated granule 4).

Example 8 A waxy substance shown in Table 1 below was heated and melted to the melting point while flowing the coated grains 4 obtained in accordance with Example 7, and then the waxy substance was sprayed on the coated grains 2. Then, a coating consisting of a thermosetting resin layer and a wax layer was formed to produce a coated pesticide granule (the wax layer coverage was 5% by weight). The coverage of the wax layer is B × 100 / (A + B), where the weight (A) of the coated particles and the weight (B) of the wax layer.

COMPARATIVE EXAMPLE 1 30 parts by weight of bentonite and 55 parts by weight of clay as a granulation aid, and 15 parts by weight of 2-benzothiazol-2-yloxy-N-methylacetanilide (purity 90%) as a poorly water-soluble agricultural chemical active ingredient Was mixed uniformly with a kneader and kneaded with water. This mixture was extruded and granulated by a screw extrusion granulator (screen diameter: 0.8 mmφ), and sized by a spherical granulator. Next, the granulated product is dried at 100 ° C. using a circulating hot air dryer and sieved, and the average particle size containing 13% of a poorly water-soluble agrochemical active ingredient is 0.8 to 1.4 m.
Pesticide granules of mφ were obtained.

Comparative Example 2 90 parts by weight of clay, 5 parts by weight of polyvinyl alcohol (average degree of polymerization: 400 to 600, fully saponified type), 2-benzothiazol-2-yloxy-N-methylacetanilide as a poorly water-soluble agricultural chemical active ingredient (Purity 70%) Water was uniformly mixed and kneaded in a kneader at a ratio of 5 parts by weight. This mixture was fed to a screw extrusion granulator (screen diameter 0.8 m).
mφ), and granulated by a spherical granulator. Next, the granulated product is dried at 100 ° C. using a hot air circulating drier and sieved to obtain a pesticide granule having an average particle size of 0.8 to 1.4 mmφ containing 3.5% of the pesticide active ingredient. Obtained. Continued
Using the spouted bed coating apparatus shown in FIG. 1, the above pesticide granules were 20% by weight of ethylene-carbon monoxide copolymer (MI = 0.75, CO = 0.95% by weight) and 80% by weight of talc (average particle size 5 μm). % Of the coating material, and the coating rate was 20% by weight under the following coating conditions. Uncoated pesticide granules: 3 kg Hot air temperature: 80 ± 2 ° C. Hot air volume: 4 m ³ / min Spray flow rate: 0.2 kg / min The coating process starts when the temperature of the flowing pesticide granules reaches a predetermined temperature. Then, after spraying for a predetermined time, drying was performed for a predetermined time to obtain a coated pesticide granule.

FIG. 3 shows the results of an aqueous dissolution test of the pesticide granules obtained in Examples 5 to 8 and Comparative Example 1. This figure 3
As is clear from the above, all of the coated pesticide granules obtained in Examples 5 to 8 are excellent in the function of slowly releasing a poorly water-soluble pesticide active ingredient, and Examples 6 and 8 are particularly effective. It turns out that the function is excellent. In Comparative Example 2, the pesticidal active ingredient was not eluted even after 40 days. Water solubility is only 4pp
When a typical poorly water-soluble pesticide of about m is used, there is a particular concern that the pesticidal active ingredient remains in the coating.

[0047]

[Table 1]

[0048]

The coated pesticide granules of the present invention can achieve the following excellent effects. (1) Labor saving of pesticide spraying and application can be achieved by timed elution control. (2) In particular, in the case of a herbicide for paddy rice that requires control of the elution suppression period in units of several days, the range of the predetermined elution suppression period is 2 to 2.
It is a short period of about 10 days, and the component elution period is about 1 to 5 days. It is necessary to suppress the initial elution and elute as quickly as possible to avoid the risk of phytotoxicity and achieve labor saving. Technical issues can also be solved. (3) Since the main component of the coating is a thermosetting resin, it has excellent strength and is suitable for long-term storage. (4) Since the product can be produced without solvent, it is a safe manufacturing method.

[Brief description of the drawings]

FIG. 1 is a flow sheet diagram of a spouted bed.

FIG. 2 is a diagram showing elution characteristics of Examples 1 to 4.

FIG. 3 is a graph showing elution characteristics of Comparative Example 1 and Examples 5 to 8.

[Explanation of symbols]

 1. Spout tower 2. Spray nozzle 3. Pesticide granules 4. Hot air temperature 5. Coating material introduction pipe

Claims (10)

[Claims] 1. A pesticide granule comprising a pesticide granule containing at least one or more poorly water-soluble pesticidal active ingredients, coated with a resin coating mainly composed of a thermosetting resin. 2. The coated pesticide granule according to claim 1, wherein the resin coating is a two- or more-layer coating comprising a coating mainly composed of a thermosetting resin and a coating mainly composed of a wax-like substance. . 3. The thermosetting resin according to claim 1, wherein said thermosetting resin is a reaction product of an acid component and an amine component.
Item 10. The coated pesticide granule according to item 8. 4. The coated agricultural chemical granule according to claim 1, wherein the thermosetting resin is a thermally modified alkyd resin. 5. The coated pesticide granule according to claim 1, wherein the thermosetting resin is a reaction product of a polyester component having an active terminal group and a polyisocyanate. 6. A thermosetting resin is added to a pesticide granule while flowing or tumbling the pesticide granule having an average particle diameter of 0.5 mm or more containing at least one or more poorly water-soluble pesticide active ingredients. Spraying or dropping a coating material to form a cured film on the surface of the pesticide granule. 7. A method according to claim 6, wherein the surface of the coated pesticide granules obtained by the production method according to claim 6 is further coated by spraying or dropping a coating material mainly comprising a waxy substance. A method for producing pesticide granules coated with at least two layers. 8. The thermosetting resin according to claim 6, wherein the thermosetting resin is a reaction product of an acid component and an amine component.
4. The method for producing a coated pesticide granule according to claim 1. 9. The method for producing a coated pesticide granule according to claim 6, wherein the thermosetting resin is a thermally denatured alkyd resin. 10. The method for producing a coated pesticide granule according to claim 6, wherein the thermosetting resin is a reaction product of a polyester component having an active terminal group and a polyisocyanate. .