TWI542282B - Producing method of water dispersible granule - Google Patents

Description

Method for producing water-dispersible granules

The present invention relates to a water-dispersible granule which has excellent water disintegratability and dispersibility even after storage at a high temperature.

The present application claims priority based on Japanese Patent Application No. 2008-216745, filed on Jan. 26,,,,,,,,,,,

Among the pesticide preparations, the water-dispersible granules are increasingly demanding because of their convenience in use, safety, and space saving during transportation, and water-dispersible granules containing various active ingredients of pesticides are currently being developed.

The water-dispersible granules are usually prepared by adding a humectant, a dispersing agent, a binder, an extender and the like to the active ingredient of the pesticide (agrochemical), and then granulating the granules into granules.

The water-dispersible granules are usually diluted with water and suspended for about 10 to 10,000 times. Water-dispersible granules are required to rapidly disintegrate and disperse after being put into water, and there have been many proposals for improving disintegration and dispersibility. If the disintegration property or the dispersibility is not good, there is a problem that the active ingredient of the pesticide in the water is separated and unevenly distributed, which causes a side effect on the crop.

It is difficult to directly granulate the active ingredient of the liquid at the normal temperature and the active ingredient of the low-melting pesticide. Therefore, a method of mixing the active ingredient of the pesticide with a large amount of inactive substances has been proposed, and a solution of the active ingredient of the pesticide is adsorbed to the carrier. Method of preparation (Non-Patent Document 1).

In addition, the following two have been proposed: a granule hydrate obtained by mixing granulation of a liquid pesticide active ingredient at a normal temperature, a saccharide, a burned product of a wet method, bentonite, and an anionic surfactant. (Patent Document 1); or a water-dispersible property obtained by adding a wet method and an anionic surfactant to a pesticidal active ingredient having a melting point of 70 ° C or less, and further adding a solvent and a water-soluble carrier for granulation Granules (Patent Document 2).

The water-dispersible granules proposed in the above-mentioned materials exhibit good disintegratability and dispersibility when they are put into water immediately after granulation or after storage at a low temperature. However, after being stored in a warehouse without a temperature adjustment device and causing prolonged exposure to a high temperature environment, there may be a problem that disintegration and dispersibility are lowered, and the active ingredients of the pesticide are separated in the water, resulting in uneven distribution. .

As an example of the improvement of disintegration property and dispersibility, it has been proposed to granulate a mixture of a pesticidal active ingredient having a melting point or a softening point of 70 ° C or less, a N-deuterated amine salt as a dispersing agent, and an adsorption carrier. The water-dispersible granule obtained (Patent Document 3). However, some countries have restrictions on the use of N-deuterated amine salts, so the water-dispersible granules described above cannot be used in countries where this restriction is used.

Patent Document 1: Japanese Patent Laid-Open Publication No. 2007-39440

Patent Document 2: Japanese Patent Laid-Open No. 3-163006

Patent Document 3: Japanese Patent Laid-Open Publication No. 2005-104959

Non-Patent Document 1: Japanese Pesticide Society pesticide preparation. Compilation of the Society of Applied Research, Guide to Pesticide Preparation, and Corporate Legal Persons Issued by the Japan Plant Epidemic Prevention Association, October 30, 1997, p. 22-24.

An object of the present invention is to provide a water-dispersible granule which has excellent water disintegratability and dispersibility even after storage at a high temperature and which has a side effect of suppressing the drug, and which contains a pesticide having a melting point or a softening point of 70 ° C or less. ingredient.

The inventors of the present invention conducted various studies to solve the above problems, and found that a premixed preparation was prepared by mixing an active ingredient of a pesticide having a melting point or a softening point of 70 ° C or less with acidic white carbon, and then premixing the mixture and alkaline. A white carbon, a polycarboxylic acid-based surfactant, and a saccharide having a molecular weight of 400 or less are mixed and granulated, whereby an excellent water disintegratability and dispersibility even after storage at a high temperature can be obtained. A water-dispersible granule whose side effects are inhibited. The present invention has been completed based on this finding and further research.

That is, the present invention is a water-dispersible granule comprising a pesticidal active ingredient having a melting point or a softening point of 70 ° C or less, acidic white carbon, basic white carbon, a polycarboxylic acid-based surfactant, and a molecular weight of 400 or less. Sugar.

In the water-dispersible granule of the present invention, the saccharide is preferably at least one selected from the group consisting of glucose, sorbitol, lactose, sucrose, and maltose. Further, the above-mentioned pesticide active ingredient is preferably Iminoctadine albesilate.

In addition, the present invention relates to a method for producing a water-dispersible granule comprising the steps of: mixing a pesticidal active ingredient having a melting point or a softening point of 70 ° C or less with acidic white carbon to prepare a premixed preparation; Alkaline white carbon, a polycarboxylic acid-based surfactant, and a saccharide having a molecular weight of 400 or less are mixed; and the obtained mixture is granulated.

The water-dispersible granule of the present invention has excellent water disintegratability and dispersibility even after storage at a high temperature. That is, disintegration and dispersibility are not lowered even after prolonged exposure to a high temperature environment even after storage in a warehouse without a temperature adjustment device. In addition, since it has excellent disintegration and dispersibility in water, the active ingredients of the pesticide in the water are not easily separated, and uneven distribution can be suppressed. As a result, the side effects of the drug are suppressed. The water-dispersible granule of the present invention can be applied to agricultural and horticultural pesticides.

The water-dispersible granule of the present invention contains a pesticidal active ingredient having a melting point or a softening point of 70 ° C or less, acidic white carbon, basic white carbon, a polycarboxylic acid-based surfactant, and a saccharide having a molecular weight of 400 or less.

[Pesticide Active Ingredients]

The agricultural chemical active ingredient used in the water-dispersible granule of the present invention has a melting point or a softening point of 70 ° C or less. The active ingredient of the pesticide may be a compound for general pesticides such as a bactericide, an insecticide, an acaricide, a plant growth regulator, a herbicide, a rodenticide, an antibacterial agent, an antifungal agent, an anti-algae agent or the like. These compounds may be used alone or in combination of two or more.

Examples of the active ingredient of the agricultural chemical having a melting point of 70 ° C or less include 2-(1,2-dimethylpropylamine)-4-ethylamino-6-methylthio-1,3,5-triazine (Dimethametryn, Common name love to kill, melting point: 65 ° C), S, S-dimethyl-2-(difluoromethyl)-4-isobutyl-6-(trifluoromethyl)-3,5-pyridinedicarboxylate Sulfurate (Dithiopyr, common name: flurazepam, melting point: 65 ° C), 2,3-dihydroxy-3,3-dimethylbenzofuran-5-ylethane benzene sulfonate (Benfuresate, common name grass Yellow, melting point: 32~35°C), butyl (R)-2-[4-(4-Cyano-2-fluorophenoxy)phenoxy]propionate (Cyhalofop-butyl, common name: butyl safflower, melting point: 50 ° C), S-1 -Methyl-1-phenethylpiperidine-1-thiocarbonate (Dimepiperate, commonly known as piperidane, melting point: 38.8 to 39.3 ° C) and the like. Further, as an active ingredient of a pesticide which is liquid at normal temperature, for example, 2-chloro-2',6'-diethyl-N-(2-propoxyethyl)-acetamidobenzene (Pretilachlor, commonly known as Pula Grass), S-benzyl-N-(1,2-dimethylpropyl)-N-ethylthiocarbamate (Esprocarb, commonly known as chlorpyrifos).

Examples of the active ingredient of the agricultural chemical having a softening point of 70 ° C or less include, for example, 1,1'-iminobis(exenyl)difluorene. Tris (alkylbenzene sulfonate) (Iminoctadine albesilate, commonly known as gram cumene benzene sulfonate, softening point 55 ~ 60 ° C) and so on.

Among these, chrome alkanebenzenesulfonate is more suitable for the water-dispersible granule of the present invention.

The water-dispersible granule of the present invention may also contain an active ingredient of a pesticide having a melting point and a softening point exceeding 70 °C. The active ingredient of the pesticide may be a compound for general pesticides such as a bactericide, an insecticide, an acaricide, a plant growth regulator, a herbicide, a rodenticide, an antibacterial agent, an antifungal agent, an anti-algae agent or the like. These compounds may be used alone or in combination of two or more.

Examples of the active ingredient of the pesticide having a melting point and a softening point of more than 70 ° C include, for example, 2-isopropylphenyl-N-methylamine formate (MIPC, common name: extinction, melting point: 88 to 93 ° C), 3, 5 -Xylphenyl-N-methylamine formate (XMC, common name: chlorpyrifos, melting point: 99-100 ° C), 3-(4-t-butyl-2-ethoxyphenyl)-2-( 2,6-difluorophenyl)-4,5-dihydroxyoxazole (Etoxazole, common name: chlorpyrifos, melting point: 101-102 ° C), O-3-tert-butylphenyl-6-methoxy- 2-Pyridyl (methyl) thiocarbamate (Pyributicarb, commonly known as oxadicarb, melting point: 85.7-86.2 ° C), 5-(2,4-dichlorophenoxy)-2-nitrobenzyl Formate (Bifenox, common name Bifino, melting point: 84 ~ 86 ° C), 1- (α, α-dimethylbenzyl)-3- (p-tolyl) urea (Dymron, commonly known as T. chinensis, Melting point: 203 ° C), N, N-diethyl -3-trimethylsulfonyl-1H-1,2,4-triazole-1-carboxamide (Cafenstrole, common name oxacillin, melting point: 114-116 ° C), methyl-α-(4, 6-Dimethoxypyrimidin-2-yl)amine,carboxamidosulfonyl]-o-toluic acid ester (Bensulfuron-methyl, common name: speed-free, melting point: 185-188 ° C), 2-bromo-N -(α,α-dimethylbenzyl)-3,3-dimethylbutyramine (Bromobutide, common name bromfenol, melting point: 180.1 ° C), 1-(2-chloroimidazole [1,2- a] Pyridin-3-ylsulfonyl)-3-(4,6-dimethoxypyridin-2-yl)urea (Imazosulfuron, commonly known as Essence, melting point: 183-184 ° C), 1-{[ O-(cyclopropylcarbonyl)phenyl]aminosulfonyl}-3(4,6-dimethoxy-2-pyrimidinyl)-urea (Cyclosulfamuron, commonly known as sulfonate, melting point: 149.6~153.2 °C) , methyl (E)-2-methoxyimino [α-(o-tolyloxy) O-tolyl] acetate (Kresoxim-methyl, commonly known as Kexinxin, melting point: 101.6~102.5 °C), Methyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate (Azoxystrobin, commonly known as Atomine, melting point :116°C), 5-{[2-amino-5-O-(aminocarbonyl)-2-deoxy-L-xylosyl]amino}-1,5- Deoxy-1-[3,4-dihydroxy-5-(hydroxymethyl)-2,4-dioxa-1(2H)-pyrimidinyl]-β-D-furfuranosyl acid (Polyoxin, common name Granules, melting point: 160 ° C or higher, bis (dimethyl thiocarbamyl) disulfide (Thiram, common name, melting point: 155 ~ 156 ° C), N- (2,3-dichloro- 4-hydroxyphenyl)-1-methylcyclohexanecarbamamine (Fenhexamid, common name Cycloheximide, melting point: 153 ° C), zinc ion coordination manganese ethylene bisdithiocarbamate (Mancozeb, common name Zinc-manganese, melting point: 192 ° C or higher, 3-(3,5-dichlorophenyl)-N-isopropyl-2,4-dioxazolidine-1-carboxamide (Iprodione, common name Common, melting point: 134 ° C), 3 '-isopropoxy-2-methylbenzamide Benzene (Mepronil, commonly known as chlorpheniramine, melting point: 92 ~ 93 ° C), (1RS, 2SR, 5SR; 1RS, 2SR,5SR)-2-(4-chlorobenzyl)-5-isopropyl-1-(1H-1,2,4-triazol-1-ylmethyl)cyclopentanol (Ipconazole, a common name inoculum) Azole, melting point: 91~119 ° C).

In the water-dispersible granule of the present invention, the melting point or softening point is 70 ° C or less The active ingredient of the drug is preferably from 0.1 to 50% by mass based on the total amount of the water-dispersible granule.

The amount of the pesticidal active ingredient having a melting point or a softening point of more than 70 ° C is usually 10% by mass or less, preferably 5% by mass or less based on the total active ingredient of the agricultural chemical.

[acid white carbon]

The acidic white carbon used in the water-dispersible granule of the present invention, in the amorphous cerium oxide powder, has a pH of usually 6 to 7, preferably 6 to 7.5. The average particle diameter d _{50 of the} acidic white carbon obtained by the laser diffraction method is usually from 1 to 500 μm, preferably from 10 to 100 μm. The particle size can be adjusted by pulverization or the like.

Examples of commercially available products of acid white carbon include CARPLEX #80 (product name / DSL Japan), CARPLEX XR (product name / DSL Japan), CARPLEX FPS-3 (product name / DSL Japan) ), CARPLEX CS-8 (product name / DSL Japan), NIPSIL NS-K (product name / manufactured by Nippon Paint Co., Ltd.), NIPSIL NS-KR (product name / manufactured by Nippon Paint Co., Ltd.), TOKUSIL NSK (product) Name / TOKUYAMA company, TOKUSIL P (product name / TOKUYAMA company).

The amount of the acid white carbon is preferably from 1 to 50% by mass, more preferably from 10 to 30% by mass based on the total amount of the water-dispersible granules.

[alkaline white carbon]

The alkaline white carbon used in the water-dispersible granule of the present invention, in the amorphous cerium oxide powder, the pH of the 1% suspension is usually 8 to 14, preferably 9 to 13, more preferably 10 ~12. The average white particle diameter d _{50 of} the alkaline white carbon obtained by the laser diffraction method is usually 2 to 100 μm, preferably 5 to 20 μm. The particle size can be adjusted by pulverization or the like.

As an example of a commercial product of alkaline white carbon, CARPLEX #100 (product) Name / DSL Japan company), CARPLEX # 1120 (product name / DSL Japan company), TOKUSIL AL-1 (product name / TOKUYAMA company), NIPSIL NA (product name / Nippon Industrial Co., Ltd.), NIPSIL G300 ( Product name / manufactured by Nippon Paint Co., Ltd.), DUROSIL (product name / DSL Japan company), EXTRUSIL (product name / DSL Japan company).

The amount of the alkali white carbon is preferably from 0.1 to 50% by mass, more preferably from 1 to 20% by mass, based on the total amount of the water-dispersible granules.

[Polycarboxylic acid surfactant]

The polycarboxylic acid-based surfactant used in the water-dispersible granule of the present invention is a polymer surfactant mainly having a carboxylic acid as a structural unit. The molecular surfactant preferably has a molecular weight of from 1,000 to 50,000. Examples of the polycarboxylic acid-based surfactant include (1) a polymer of an ethylenically unsaturated monocarboxylic acid; (2) an ethylenically unsaturated monocarboxylic acid and an ethylenically unsaturated dicarboxylic acid or an anhydride thereof. a polymer; (3) an ethylenically unsaturated monocarboxylic acid or an ethylenically unsaturated dicarboxylic acid or an anhydride thereof, and a polymer composed of a olefin having 2 to 6 carbon atoms; (4) an ethylenically unsaturated monocarboxylic acid Or an ethylenically unsaturated dicarboxylic acid or an acid anhydride thereof, a polymer composed of an aromatic vinyl compound, and the like.

Examples of the ethylenically unsaturated monocarboxylic acid include acrylic acid, methacrylic acid, and crotonic acid.

Examples of the ethylenically unsaturated dicarboxylic acid include maleic acid, fumaric acid, and itaconic acid.

Examples of the alkene having 2 to 6 carbon atoms include ethylene, propylene, butylene, isobutylene, and diisobutylene.

Examples of the aromatic vinyl compound include styrene, α-methylstyrene, vinyltoluene, and p-methylstyrene.

Specific examples of the polycarboxylic acid-based surfactant include polyacrylic acid and propylene. a copolymer of acid and maleic acid, a copolymer of isobutylene and maleic anhydride, a copolymer of acrylic acid and itaconic acid, a copolymer of methacrylic acid and itaconic acid, maleic acid and a copolymer composed of styrene, a copolymer of maleic acid and diisobutylene, and the like. In addition, examples of the salt include alkali metal salts such as lithium, sodium, and potassium; alkaline earth metal salts such as calcium and magnesium; and amine salts and ammonium salts such as monomethylamine, monoethylamine, and dimethylamine.

The salt of the copolymer of isobutylene and maleic anhydride is exemplified by ISOBAN 600SF35 (product name: KURARAY Co., Ltd.); and the salt of the copolymer of isobutylene and maleic anhydride is Toxanon GR31A (product name / Sanyo Chemical Co., Ltd.) As a polyacrylate, BOYSS 530 (product name / Kao company) can be mentioned; as polyacrylic acid ammonium, BOYSS 532A (product name / Kao company) can be mentioned; as a copolymer of acrylic acid and maleic acid, salt can be mentioned. BOYSS 520 (product name / Kao company) or BOYSS 521 (product name / Kao company); as a copolymer of maleic acid and alkene, NEWKALGEN WG-5 (product name / manufactured by Takeshi Oil Co., Ltd.), S - SMA3000 (product name / manufactured by ARCO CHEMICAL Co., Ltd.), S-SMA1000 (product name / manufactured by ARCO CHEMICAL Co., Ltd.), S-SMA1440H (product name / manufactured by ARCO CHEMICAL Co., Ltd.), POLYSTAR OMP (product name / manufactured by Nippon Oil & Fats Co., Ltd.), POLYSTAR OMA (product name / manufactured by Nippon Oil & Fats Co., Ltd.), POLYSTAR SMX (product name / manufactured by Nippon Oil & Fats Co., Ltd.), POLYSTAR SM-1015 (product name / manufactured by Nippon Oil & Fats Co., Ltd.), POLYSTAR A-1060 (product name / manufactured by Nippon Oil & Fats Co., Ltd.) ), Sokalan CP-5 (product name / BASF company), Sok Alan CP-7 (product name / BASF company), Sokalan CP-9 (product name / BASF company), Sokalan CP-10 (product name / BASF company), GEROPON T/36 (product name / Rhone Poulenc company ), GEROPON TA/72 (product name / manufactured by Rhone Poulenc Co., Ltd.), GEROPON SC/213 (product name / manufactured by Rhone Poulenc Co., Ltd.), or Sorpol-7248 (product name / manufactured by Toho Chemical Co., Ltd.).

The amount of the polycarboxylic acid-based surfactant is not particularly limited, and is usually 0.5 to 10% by mass, preferably 1 to 7% by mass based on the total amount of the water-dispersible granules.

[carbohydrate]

Examples of the saccharide used in the water-dispersible granule of the present invention include monosaccharides having a molecular weight of 400 or less, and disaccharides and derivatives thereof. Preferable examples thereof include glucose, galactose, mannose, fructose, maltose, sorbitol, lactose, sucrose, and mannitol. More preferably, glucose, sorbitol, lactose, sucrose, and maltose are mentioned. These saccharides may be used singly or in combination of two or more.

The amount of the saccharide having a molecular weight of 400 or less is not particularly limited, and is usually 1 to 15% by mass, preferably 2 to 10% by mass based on the total amount of the water-dispersible granules.

The water-dispersible granule of the present invention may further contain a wetting agent, an extender, and a binder other than the above. In this case, the blending ratio of the above constituent components is preferably maintained within the above range.

Examples of the wetting agent include sodium alkylnaphthalenesulfonate, sodium alkylsulfate, sodium alkylbenzenesulfonate, sodium alkylsulfonated succinate, and polyoxyethylene alkyl aromatic ether.

Examples of the extender include mica, calcium carbonate, kaolin, clay, bentonite, diatomaceous earth, zeolite, erbium, acid white clay, talc, magnesium carbonate, titanium oxide, ammonium sulfate, sodium sulfate, urea, and the like.

Examples of the binder include carboxymethylcellulose, polyvinyl alcohol, polyvinylpyrrolidone, dextrin, soluble starch, and the like.

The shape of the water-dispersible granule of the present invention varies depending on the preparation method, conditions, and the like, and is usually amorphous, cubic, rectangular, trigonal, conical, or cylindrical. Ball shape, dumbbell shape, ellipsoid shape, egg shape, convex lens shape, concave lens shape, plate shape, and the like. Among them, it is preferably amorphous, cylindrical, spherical or ellipsoidal. Further, the size of the water-dispersible granules is preferably 0.1 to 5 mm in the maximum length portion.

The particle size of the water-dispersible granule of the present invention is preferably from 50 μm to 2000 μm. The range, more preferably, is in the range of 100 μm to 800 μm. Wherein, the particle diameters do not need to make all the particles into the particle diameters within the ranges, as long as the particle diameter (i.e., the mode particle diameter) of the most particles in the total particle size distribution is within the ranges. Further, only particles of a desired particle size can be obtained by classification.

[Method for producing water-dispersible granules]

The water-dispersible granule of the present invention may use a pesticidal active ingredient having a melting point or a softening point of 70 ° C or less, acidic white carbon, basic white carbon, a polycarboxylic acid-based surfactant, and a sugar having a molecular weight of 400 or less, and It is produced by a known method.

For example, an active ingredient or an acid having a melting point or a softening point of 70 ° C or less can be used. White carbon, basic white carbon, polycarboxylic acid surfactant, and a sugar having a molecular weight of 400 or less, and optionally a wetting agent (dialkylsulfonated succinate, etc.), an extender, and The binder and the solvent (water, alcohol, etc.) added as the case may be simultaneously mixed, extruded, and dried to be produced. Further, after drying, it is also possible to perform granulation such as grinding.

In addition, when the active ingredient of the pesticide is in a liquid state at a normal temperature, the component other than the active ingredient of the pesticide may be extruded in the same manner as described above to obtain a granule, and the granule may be absorbed into the liquid active ingredient of the pesticide. Manufacturing.

As a method of obtaining the water-dispersible granule of the present invention, the following method is preferred: The preparation method comprises the following steps: the active ingredient and the acidity of the pesticide having a melting point or a softening point of 70 ° C or less Mixing white carbon to obtain a premixed preparation; mixing the premixed preparation, basic white carbon, polycarboxylic acid type surfactant, and saccharide having a molecular weight of 400 or less; and granulating the obtained mixture . After granulation, it may be further dried, pulverized, and classified as appropriate.

(premixing step)

The active ingredient of the pesticide having a melting point or a softening point of 70 ° C or less is mixed with acidic white carbon. A premixed preparation was thus prepared.

For the mixing of the pesticidal active ingredient and the acidic white carbon, for example, a mixer such as a ribbon mixer, a Nauter mixer, a mixing granulator or the like can be used.

The active ingredient of the pesticide can be directly used by mixing the raw material itself with acidic white carbon, or by dissolving the raw material itself in a solvent to prepare a solution, and mixing the solution with acidic white carbon for use.

Examples of the solvent for dissolving the active ingredient of the agricultural chemical include alcohols such as methanol and ethanol; ketones such as acetone and methyl ethyl ketone; aromatic hydrocarbons, fatty acid esters, phthalic acid esters, and vegetable oils.

When the active ingredient of the pesticide is used in the form of a liquid (when the raw material of the active ingredient of the pesticide itself is a liquid or when the solution is prepared as described above), the active ingredient of the pesticide is easily adsorbed to the acidic white carbon. In addition, when the active ingredient of the pesticide is mixed with the acidic white carbon, it can be aggregated into a lump.

Further, the solvent may be removed by mixing the active ingredient of the pesticide with acidic white carbon by heating or decompression.

The mixture obtained by mixing the active ingredient of the pesticide with the acidic white carbon may be pulverized as appropriate. The pulverizing means is not particularly limited, and examples thereof include a dry pulverizer such as a fine pulverizer, a hammer mill, a ball mill, and a jet mill.

(formal mixing step)

Next, an alkaline white carbon, a polycarboxylic acid type surfactant, a saccharide having a molecular weight of 400 or less, and optionally a wetting agent and other additives are added to the premixed preparation. The mixing means is not particularly limited, and may be appropriately selected from those listed in the means for use in the premixing step. When the mixture is officially mixed, the active ingredients of the pesticide can be further added. The active ingredients of the pesticide added in the formal mixing may be the same as or different from those added during the pre-mixing.

The mixture may be comminuted after formal mixing. The pulverization means is not particularly limited, and may be appropriately selected from those listed in the means for use in the premixing step.

(Add water mixing step)

After the mixing step, the mixture can be kneaded while being moistened with water. The method of adding water can use well-known conditions and means. For example, methods such as dropping, spraying, or spraying. A kneading machine can be used for mixing. Examples of the kneading machine include a nano-type mixer, a rotary belt mixer, a Henschel mixer, and a kneader. Among these, a kneader is preferred.

The water added in the kneading is not particularly limited. Examples thereof include purified water such as tap water, industrial water, distilled water, ion exchange resin treated water, reverse osmosis membrane (RO) treated water, and ultrafiltration membrane (UF) treated water; natural materials such as groundwater, well water, and river lake water. water. The amount of water added during kneading is usually from 3 to 70% by weight, preferably from 5 to 60% by weight, based on the mixture. The kneading time varies depending on the scale of manufacture and the type of kneading machine, and is preferably from 3 minutes to 60 minutes, preferably from 5 minutes to 20 minutes.

(granulation step)

Next, the obtained kneaded material was granulated. Examples of the granulator include a basket granulator; a horizontal extruder, a twin doom granulator, a single doom granulator, a granulator, and the like. , compression granulators such as wheel presses. Among these, it is preferred to use a squeezing granulator. The extruded particle size varies depending on the raw material used and/or the amount of water added, and is preferably 0.2 to 2.0 mm, more preferably 0.5 to 1.2 mm.

(drying and granulating steps)

The granules obtained by the above method can be directly used as the water-dispersible granules of the present invention, and can also be dried, sized or classified as the water-dispersible granules of the present invention as the case may be.

The drying step is not particularly limited as long as the water added in the kneading step or the like can be removed without causing chemical changes in the composition. The drying temperature and drying time vary depending on the amount of water added and the device used. The temperature can usually be set to room temperature to 100 ° C, preferably 40 ° C to 90 ° C, and the time can usually be set to 2 minutes to 3 hours. Good for 10 minutes to 1 hour. Examples of the dryer include a ventilating belt dryer, a stirring dryer, a fluidized bed dryer, a vibration dryer, and a bed dryer.

The granulator is not particularly limited as long as it can obtain an appropriate particle diameter. For example, a screw extruder such as a meat grinder (made by Hiroshima Co., Ltd.) or an extrusion granulator (FUJIPAUDAL Co., Ltd.), or a Rotor Prex (ROATPLEX, manufactured by Hosokawa Micron Co., Ltd.) may be mentioned. ) such as a grinder, a ball granulator, a fine pulverizer, etc., such as a solid pulverizer or a roll granulator (manufactured by GRANULATOR Co., Ltd., Japan).

The classifier is not particularly limited. For example, a rotary screen or an electromagnetic vibrating type screening machine can be cited.

[Method of application of water-dispersible granules]

The water-dispersible granule of the present invention can be applied to crops, soil, or the like by a spray machine or the like after being dispersed and diluted in water. The dilution ratio of water varies depending on the type, content, and application purpose of the active ingredient of the pesticide in the water-dispersible granule, and is usually 10 to 10,000 times, preferably 50 to 8,000. The ratio is preferably 500 to 4000 times.

The water used for dilution and suspension is not particularly limited, and either soft water or hard water can be used. Examples thereof include purified water such as tap water, industrial water, distilled water, ion exchange resin treated water, reverse osmosis membrane (RO) treated water, and ultrafiltration membrane (UF) treated water; natural materials such as groundwater, well water, and river lake water. water. As the hard water, for example, the so-called CIPAC standard water D (342 ppm (Ca ²⁺ : Mg ²⁺ = 4:1)) by the CIPAC (Collaborative International Pesticide Analytical Council) method is exemplified, but is not limited thereto. .

[Package form of water-dispersible granules]

The water-dispersible granules of the present invention may be used in aluminum bags, paper bags, cartons, bottles, etc., and are generally used in containers or packages of granules or wettable powders. In order to avoid moisture, it is preferably an aluminum bag or an aluminum-plated paper bag, a polymer bag, a PET bottle or the like. Further, the water-dispersible granules packaged in the water-soluble cartridge can be filled in a bag for preventing such moisture, thereby preventing moisture from being stored, improving safety, and improving usability during dilution.

Example

The present invention will be specifically described below by way of examples and comparative examples, but the present invention is not limited to the examples.

(Example 1)

50 parts by mass of the alkylbenzenesulfonate (softening point: 60 ° C) was dissolved in 50 parts by mass of methanol. This solution was mixed with acidic white carbon (manufactured by Sasano Yeon Pharmaceutical Co., Ltd., product name "CARPLEX XR", 50 parts by mass, and heated at 50 ° C to remove methanol. The obtained powdery mixture was sprayed with a jet mill (Nippon Pneumatic Mfg). The product name "Supersonic Jet Mill PJM" manufactured by Co., Ltd. was pulverized to obtain granules (premixed preparation) containing 50% of alkane sulfonate.

3.4 parts by mass of cyflufenamid (common name cycloheximide, manufactured by Nippon Soda Co., Ltd., melting point: about 62 ° C), 40 parts by mass of the above premixed preparation, and basic white carbon (product name "CARPLEX # 1120" manufactured by DSL Japan Co., Ltd.) 25 parts by mass, 25 parts by mass of sodium polycarboxylate (product name "NEWKALGEN WG-5" manufactured by Takeshi Oil Co., Ltd.), 5 parts by mass of sorbitol, and dioctyl sulfosuccinate (made by Takeshi Oil Co., Ltd., product name "NEWKALGEN EX -70" (containing 30% benzoic acid)) 3 parts by mass and 13.6 parts by mass of potassium chloride were pulverized by an air pulverizer (manufactured by Nisso Engineering Co., Ltd., product name "ULMAX"). 46.5 parts by mass of water was added thereto and kneaded, and extrusion granulation was carried out using a 0.7 mm sieve, followed by drying at 50 ° C in a fluidized bed dryer (FREUND/Okawara Seisakusho Co., Ltd., FLOW COATER (FLO-1)), followed by drying for 30 minutes. After rescreening, the fraction remaining on the sieve of 0.15 to 0.50 mm was screened to obtain a water-dispersible granule.

(Comparative Example 1)

The same operation as in the first embodiment was carried out except that the acid white carbon (product name "CARPLEX # 80" manufactured by DSL Japan Co., Ltd.) was used instead of the alkaline white carbon (manufactured by DSL Japan Co., Ltd., product name "CARPLEX #1120"). , obtaining water-dispersible granules.

(Comparative Example 2)

The water-dispersible granules were obtained in the same manner as in Example 1 except that the amount of sorbitol was changed to 0 parts by mass and the amount of potassium chloride was changed to 18.6 parts by mass.

(Comparative Example 3)

The same operation as in Comparative Example 2 was carried out except that the acid white carbon (product name "CARPLEX # 80" manufactured by DSL Japan Co., Ltd.) was used instead of the alkaline white carbon (manufactured by DSL Japan Co., Ltd., product name "CARPLEX # 1120"). , obtaining water-dispersible granules.

The water-dispersible granules obtained in the examples and the comparative examples were subjected to the following methods. evaluation of. These results are shown in Table 1.

(evaluation of self-dispersibility)

In a test tube containing 100 mL of water so that the distance from the water surface to the bottom is about 180 mm into a 30 mL test tube, 100 mL of hard water of 3 degrees is charged according to the pesticide step inspection method, and water-dispersible granules are slowly added thereto to observe the water. The state in which the dispersible granules sink to the bottom is determined by the following criteria.

○: The water-dispersible granules began to disintegrate between the bottoms of the contact tubes.

×: The water-dispersible granules did not completely disintegrate between the bottoms of the contact tubes.

○ indicates self-dispersibility; × indicates no self-dispersibility; ○~× indicates substantially self-dispersibility, but some particles have no self-dispersibility. ×~○ indicates that there is substantially no self-dispersibility, but some of the particles have self-dispersibility.

(evaluation of disintegration)

In a test tube containing 100 mL of water so that the distance from the water surface to the bottom was about 180 mm, 30 mL of hard water was charged according to the pesticide step inspection method, and the water-dispersible granules were slowly added thereto. After 30 seconds passed, the test tube was inverted and restored at a frequency of 2 seconds, and the number of inversions (referred to as the number of disintegrations) until the water-dispersible granules completely disintegrated was measured. The less the number of disintegration reversals, the better the disintegration.

(Settling amount (dispersibility))

After the number of times of disintegration inversion was measured, the test tube was further reversed and restored 30 times at a frequency of 2 seconds. The amount of sedimentation (mL) was measured after 30 minutes from the end of the reverse operation of the reverse. The smaller the amount of sedimentation, the more excellent the dispersibility.

(High temperature storage test)

The water-dispersible granules obtained in the examples and the comparative examples were placed in a constant temperature room at 54 ° C for 14 days. The self-dispersibility, disintegratability, and sedimentation amount were evaluated in the same manner as described above for the water-dispersible granules after the high-temperature storage for 14 days.

As shown in Table 1, the water-dispersible granules of the conventional formulation have self-dispersibility at the time of completion of production, and are excellent in disintegration property in water and dispersibility. However, in the case of storage after high temperature, the self-dispersibility disappears, and the disintegratability and dispersibility are lowered.

On the other hand, the water-dispersible granule of the present invention maintains self-dispersibility even after storage at a high temperature, and the degree of reduction in disintegratability and dispersibility is also small.

Since the water-dispersible granule of the present invention does not reduce disintegration and dispersibility even after storage at a high temperature, it can be applied to agricultural and horticultural pesticides.

Claims (1)

A method for producing a water-dispersible granule comprises the steps of: preparing an active ingredient of a pesticide having a melting point or a softening point of 70 ° C or less and an acid white having an average particle diameter d ₅₀ of 1 to 500 μm obtained by a laser diffraction method; After mixing the carbon to obtain a premixed preparation; the premixed preparation, the basic white carbon having an average particle diameter d ₅₀ of 2 to 100 μm and a polycarboxylic acid having a molecular weight of 1,000 to 50,000 obtained by a laser diffraction method The surfactant is mixed with a saccharide having a molecular weight of 400 or less; and the resulting mixture is granulated.