JP2929112B2 - Manufacturing method of hydrated granular pesticides - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION 1) Object of the Invention (1) Field of Industrial Application The present invention relates to a method for producing hydrated granular pesticides.

(2) Prior art In recent years, hydrated granules have come to be used as pesticide preparations that can be safely used without scattering fine powder and have excellent storage stability. As a method of obtaining this, hitherto, a water-insoluble or hardly soluble solid pesticidal active ingredient is heated and dried to reduce the average particle diameter to 3 μm or less by a wet pulverization method and to remove water used as a dispersion medium. Or,
Spray drying methods have been used.

(3) Problems to be Solved by the Invention However, in these methods, since heat is applied, some pesticidal active ingredients cause particle growth of the pesticidal active ingredient, and the finely pulverized particles return to the original size, or It becomes bigger than that and loses the biological effect,
Hydrated granules produced using an active ingredient having such a particle size cause problems such as not being able to obtain desired physical properties.

An object of the present invention is to provide a method for producing a hydrated granule which does not have such a problem.

2) Configuration of the Invention (1) Means for Solving the Problems The present inventors have developed a method for producing a hydrated granular pesticide having good physical properties, in which no particle growth of the pesticidal active ingredient occurs during the production process. We studied diligently. As a result, a suspension obtained by adding a water-insoluble or hardly soluble solid pesticidal active ingredient to water and a surfactant and wet-pulverizing the resulting mixture is freeze-dried, mixed with adjuvants, carriers, etc. The present inventors have found that a hydrated granular pesticide meeting the above object can be obtained by granulation, and have reached the present invention. As a result of further studies, the production method of the present invention is a method of freeze-drying a suspension obtained by wet-pulverizing a water-insoluble or hardly soluble solid pesticide active ingredient together with a surfactant, an auxiliary agent, a carrier, and the like, followed by granulation. Alternatively, it is also effectively manufactured by a method in which an auxiliary agent, a carrier, etc. are mixed with a suspension obtained by wet-grinding a solid agricultural chemical active ingredient insoluble or hardly soluble in water together with a surfactant, freeze-dried, and then granulated. I knew it could be done.

Therefore, the present invention includes these methods (to). The water-insoluble or hardly soluble solid pesticidal active ingredient that can be used in the present invention is not particularly limited. Examples include the following: However, the solid agrochemical active ingredient that is hardly soluble in water includes those having a solubility in water of about 1% by weight or less.

Examples of fungicides Basic copper chloride, cupric hydroxide, sulfur, zineb, maneb, manzeb, polycarbamate, ziram, thiuram,
Captan, diphortan, diclofluanid, TPN,
Fusaride, tolclofosmethyl, thiophanatemethyl, benomyl, iprodione, procymidone, PCNB, dazomet, chloroneb, triphenyltin hydroxide, dithianone, phenazine oxide, CNA, triazine, mepronil, probenazole, isoprothiolane, metasulfocarb, fluoroimide, triforine, triadimefon, 4-chlorobenzyl N- (2,4-dichlorophenyl) -2- (1,2,4-triazol-1-yl) ethanethioimidate and the like.

Examples of insecticides PMP, DMTP, CVMP, dimethylvinphos, salicion, N
AC, MTMC, MIPC, PHC, XMC, Pirimicarb, Bendicarb, CPCBS, Kelsen, Chloropropylate, Phenisobromolate, Tetradiphone, Quinomethionate, Amitraz, Benzomate, Binapacryl, Mesulfenphos, Bensultap.

Examples of herbicides MCPB, naproanilide, ioxinil, CNP, clomethoxynil, bifenox, MCC, phenmedipham, MBPMC, DCPA, napropamide, propizamide, DCM
U, Linuron, Siduron, Daimron, Simazine,
Atrazine, propazine, amethrin, promethrin,
Cyanadine, renacil, PAC, norflurazon, oxadiazon, pyrazolate, trifluralin, bethrosin, nitralin, pendimethalin, TCTP, amiproposmethyl, ACN, DBN, DCBN, acephenone, chlorphthalim, 2-｛(±) -2- [ 4- (3,5-dichloropyrrolidin-2-yloxy) phenoxy] propionyl {isoxazolidine, methyl 2-{[(4,6-dimethoxypyrimidin-2-yl) aminocarbonyl] aminosulfanylmethyl} benzoate, 3,7- Dichlor-
8-quinolinecarboxylic acid, ethyl-5- [3- (4,6-
Dimethoxypyrimidin-2-yl) -ureidosulfonyl] -1-methylpyrazole-4-carboxylate,
N- [2 '-(3'-methoxy) -thienylmethyl]-
N-chloroaceto-2,6-dimethylanilide, 1- (2
-Chlorobenzyl) -3- (α, α-dimethylbenzyl) urea, 2- [4- (2,4-dichloro-m-trioyl) 1,3-dimethylpyrazol-5-yloxy]-
4'-methylacetophenone and the like.

The active ingredient name is "Agrochemical Handbook 1985 Edition"
(Published by the Japan Plant Protection Association)

The surfactant used in the present invention can be used without particular limitation as long as it is generally used in agricultural chemical formulations. For example, nonionic surfactants include polyoxyethylene (hereinafter referred to as POE) alkyl ether, POE alkyl phenol ether, polyoxypropylene polyoxyethylene (block or random) alkyl ether, POE styrenated phenol ether, POE sorbitan fatty acid Esters, etc., and examples of the anionic surfactant include alkylbenzene sulfonate, naphthalenesulfonic acid formalin condensate, dialkyl sulfosuccinate, alkyl phosphate salt, POE alkyl sulfate salt, lignin sulfonate and the like.
Of course, these may be used alone or in combination of two or more.

The amount of these surfactants used varies depending on the nature of the pesticidally active ingredient to be used after wet pulverization, but generally it may be 10% by weight or less based on the amount of the pesticidally active ingredient.

The carrier of the present invention can be used as long as it is commonly used in agricultural chemical formulations. For example, clay, kaolin, sericite, zigrite, talc, acid clay, calcium carbonate, magnesium carbonate, diatomaceous earth, silica stone, minerals such as bentonite, water-soluble inorganic salts such as sodium sulfate, potassium chloride, ammonium sulfate, glucose, and lactose And sugars such as fructose and sucrose, enzyme-modified dextrins, starches such as acid-degraded starch, oxidized starch, pregelatinized starch and starch derivatives. These may be used alone or as a mixture of two or more.

Auxiliaries include surfactants, antioxidants, ultraviolet absorbers, hydrolysis inhibitors, foam inhibitors, disintegration spreaders, binders, and the like.

For the wet pulverization of the present invention, any wet pulverization apparatus usually used for pulverizing pesticides can be used. For example, Dynomill (Willy A. Bachofen AG wet grinder),
Sand glider (wet pulverizer manufactured by Igarashi Kikai Co., Ltd.),
Attritors (wet pulverizer manufactured by Mitsui Miike Seisakusho) and the like can be mentioned.

The lyophilization used in the present invention can be performed using a commercially available lyophilizer according to pressure and temperature conditions usually used for removing water. Although this method is not particularly limited, for example, the following method can be mentioned. That is, the suspension obtained by wet pulverization is put into a round-bottom flask, rapidly cooled to -10 ° C or lower with dry ice-acetone, and frozen. Freeze-dry the flask (VIRT
IS 10-147 MRBA) and reduce the pressure to 0.02 mmHg or less.
By returning to room temperature while maintaining the pressure at 0.02 mmHg,
Sublimates moisture. In this case, heating may be performed if necessary.

As the granulation method of the present invention, any granulation method usually used for the production of pesticide granules can be used. For example,
Extrusion granulation, tumbling granulation, crushing granulation, fluidized granulation, and the like can be given. The particle size and shape can be arbitrarily changed depending on the pesticidal active ingredient and the dilution method, and are not particularly limited.

(2) Examples Examples will be given below, but the present invention is not limited to these examples.

All parts in the examples are parts by weight.

Example 1 (Method A) POE nonylphenyl ether (surfactant) in 50 parts of water
After dissolving 2 parts, 50 parts of procymidone (a poorly water-soluble solid pesticidal active ingredient) is dispersed and wet-ground using a Dynomill to obtain a suspension having an average particle diameter of 0.6 μm. Put this suspension in a flask and dry ice-acetone at -10 ° C.
After quenching and freezing, freeze dryer (VIRTIS 10-147)
MRBA) and reduce the pressure to 0.02mmHg or less, and reduce the pressure to 0.02mmHg.
Return to room temperature while maintaining Hg to remove moisture. To 52 parts of the dried product, 5 parts of lignin sulfonate and 43 parts of enzyme-modified dextrin were added and mixed by a hammer mill, 10 parts of water was added, and the mixture was extruded and granulated by a granulator.
mm granules are obtained.

Example 2 (Method B) After dissolving 2 parts of POE sorbitan monolaurate (surfactant), 5 parts of ligninsulfonate and 43 parts of enzyme-modified dextrin in 200 parts of water, NAC (solid water-insoluble solid pesticide) was dissolved. (Active ingredient) 50 parts are dispersed and wet-pulverized using a dyno mill to obtain a suspension having an average particle diameter of 0.6 μm. This suspension was placed in a flask, quenched to -10 ° C. with dry ice-acetone and frozen, and then connected to a freeze dryer to obtain 0.02 mmHg.
The pressure is reduced as follows, and the temperature is returned to room temperature while maintaining the pressure at 0.02 mmHg to remove water. The dried product is mixed with a hammer mill, 10 parts of water is added to 100 parts of the dried product, and the mixture is extruded and granulated by a granulator. After drying, the mixture is sieved to obtain 0.3 to 0.7 mm granules.

Example 3 (Method C) After dissolving 2 parts of POE nonylphenyl ether sulfate salt (surfactant) in 50 parts of water, 5 parts of DCPA (poorly water-soluble solid pesticidal active ingredient) was dispersed, and the mixture was dispersed using a Dynomill. Wet pulverization gives a suspension with an average particle size of 0.6 μm. To this suspension, 5 parts of lignin sulfonate and 43 parts of enzyme-modified dextrin are added and mixed with stirring. Put this in a flask,
After rapidly cooling to -10 ° C with dry ice-acetone and freezing, the pressure is reduced to 0.02 mmHg or less by connecting to a freeze dryer, and the pressure is returned to room temperature while maintaining the pressure at 0.02 mmHg to remove water. The dried product was mixed with a hammer mill, and 100 parts of the dried product was extruded by adding 10 parts of water, granulated, dried, and sieved.
A granule of 3-0.7 mm is obtained.

3) Effects of the Invention (1) According to the production method of the present invention, a hydrated granular pesticide preparation having good physical properties and having no particle growth of the pesticidal active ingredient in the production process as compared with the conventional technique can be obtained. .

(2) Test Examples The usefulness of the present invention is proved by test examples.

The physical properties of the suspensions and hydrated granules prepared according to the examples were measured by the following methods.

(I) Average particle diameter after drying The average particle diameter of the wet-pulverized suspension and that obtained by drying and suspending by adding water again are measured using a Coulter Counter TA-II type (particle size distribution manufactured by Coulter Electronics Co., Ltd.). Measurement device).

(Ii) Dispersion particle size of hydrated granules Water is added to a stoppered cylinder, and the hydrated granules are added so as to be diluted 500 times. After the stopper is closed, the cylinder is inverted to sufficiently disperse the hydrated granules. The average particle size of the dispersion is measured with a Coulter Counter TA-II.

(Iii) Dispersibility of hydrated granules 50 hydrated granules were placed in a 200 ml stoppered cylinder filled with 150 ml of water.
Put in g for 1 minute. Invert 30 times vigorously after standing,
The state of dispersion was observed according to the following criteria.

Evaluation criteria of dispersion state ○: uniform dispersion △: not dispersed ×: aggregation The results are shown in Table 1.

Claims (3)

(57) [Claims] 1. A suspension obtained by adding a water-insoluble or hardly soluble solid pesticidal active ingredient to water and a surfactant, and wet-grinding the resulting mixture, freeze-drying the suspension, mixing it with adjuvants and carriers, and forming the suspension. A method for producing a hydrated granular pesticide, comprising granulating. 2. A suspension obtained by wet-grinding a solid agricultural chemical active ingredient insoluble or hardly soluble in water together with water, a surfactant, a carrier and, if necessary, an auxiliary, is freeze-dried, and then granulated. A method for producing hydrated granular pesticides. 3. A suspension obtained by wet-grinding a solid agricultural chemical active ingredient insoluble or hardly soluble in water together with water and a surfactant, mixing with a carrier and, if necessary, an auxiliary, freeze-drying the mixture, and then forming the mixture. A method for producing a hydrated suspension pesticide, comprising granulating.