JP2009079000A - Pesticide granules with improved water release - Google Patents

Abstract

The present invention provides an agrochemical granule capable of eluting an agrochemical active ingredient having a water solubility of 5 ppm or less at 20 ° C. into water in a short time.
[Solution] (a) Agrochemical active ingredient having water solubility at 20 ° C. of 5 ppm or less, (b) Apparent specific gravity of 0.02 to 0.20, particle size of 100 to 2000 μm, and floating rate after 2 hours. 70% or more water-floating carrier, (c) tripolyphosphate, (d) alkylbenzene sulfonate, and (e) other agrochemical pesticide particles having improved elution into water Agent.
[Selection figure] None

Description

  The present invention relates to an agrochemical granule having improved solubility of an agrochemical active ingredient having a water solubility at 20 ° C. of 5 ppm or less.

  In recent years, from the viewpoint of environmental protection and the like, it has been studied to reduce the application amount of agrochemical granules to paddy fields from 3-4 kg per 10a to a low application rate of 1-0.5 kg. However, in the case of a low application rate, the number of grains per unit area decreases, so that it is difficult to uniformly spread the pesticidal active ingredient throughout the paddy field. In particular, in the case of an pesticidal active ingredient with extremely low water solubility, the pesticidal active ingredient is not eluted in water, or even if it is eluted, the pesticidal active ingredient is adsorbed to the soil and the active ingredient's original effect is fully exerted. May not be possible.

  As a measure for solving such a problem, for example, an agrochemical granule containing lignin sulfonate and tripolyphosphate (Patent Document 1) having excellent disintegration property, an agrochemical dissolved in a water-insoluble organic solvent and supported on a carrier Pesticide granules (Patent Document 3), dialkyl sulfosuccinate salt and lignin sulfonate containing an anionic surfactant which is a granule (Patent Document 2), tripolyphosphate, α-olefin sulfonate and a solid carrier Pesticide granules supported on a calcined pumice (Patent Document 4), Emulsions dissolved in water emulsification-imparting base and impregnated in water-containing silicon dioxide impregnated with water-containing silicon dioxide impregnated dispersible agricultural chemical granules for paddy fields ( Patent Document 5), a pesticide comprising calcined pumice coated with a water-soluble polymer, polyoxyethylene sorbitan (or sorbitol) fatty acid ester and other oily surfactant Agents (Patent Document 6), water-soluble salts of copolymers of isobutylene or diisobutylene and maleic acid or maleic anhydride, sulfonate-based dispersants, and agricultural chemical granules containing calcium carbonate (Patent Document 7) Are known. However, the pesticide granule for paddy field containing these elution promoters has insufficient solubility in water in a short period of time when the pesticidal active ingredient is a poorly water-soluble component having a water solubility of 5 ppm or less. There is a disadvantage that there are cases.

  Moreover, in order to improve the dispersion and release of an agrochemical active ingredient in water, an agrochemical granule using foamed shirasu, calcined vermiculite, foamed perlite or cork as a carrier has been proposed (Patent Document 8). Since this granule floats on the water surface, it has a drawback that it is easily affected by wind and the like.

JP-A-6-298602 JP-A-9-12406 Japanese Patent Laid-Open No. 10-109904 JP 11-31004 A Japanese Patent Laid-Open No. 11-43402 JP 2000-319106 A JP 2003-306403 A JP-A-8-99802

  The object of the present invention is that when applied to paddy fields, the pesticide active ingredient is highly soluble in water in a short time and can exhibit a sufficient pesticide effect, and the water solubility at 20 ° C. is 5 ppm or less. It is to provide an agrochemical granule containing a water-soluble agrochemical active ingredient.

  As a result of intensive investigations to achieve the above-mentioned object, the present inventors have determined that an agrochemical active ingredient having a water solubility at 20 ° C. of 5 ppm or less is a water surface having a specific apparent specific gravity, particle size, and floating rate. Pesticides with floating carriers, tripolyphosphates, alkylbenzene sulfonates and other carriers can improve the dissolution into water, and the agrochemical activity can be dissolved in water in a short time, thus providing a sufficient effect. It has been found that a granule can be obtained, and the present invention has been completed.

  Thus, the present invention comprises (a) an agrochemical active ingredient having a water solubility at 20 ° C. of 5 ppm or less, (b) an apparent specific gravity of 0.02 to 0.20, a particle size of 100 to 2000 μm, and floating water after 2 hours Improved elution in water characterized by containing a water-floating carrier having a rate of 70% or more, (c) tripolyphosphate, (d) alkylbenzene sulfonate and (e) other carrier An agrochemical granule is provided.

  Hereinafter, the agrochemical granule of the present invention will be described in more detail.

BEST MODE FOR CARRYING OUT THE INVENTION

  In the present invention, the agrochemical active ingredient (a) includes generally agrochemically active ingredients such as herbicides, plant growth regulators, insecticides, fungicides and the like. A pesticidal active ingredient hardly soluble in water having a solubility of 5 ppm or less, particularly 3 ppm or less is targeted.

  As herbicides, for example, phenoxy acid, carbamate, acid amide, acetanilide, urea, sulfonylurea, pyrimidyloxybenzoic acid, triazine, diazine, diazole, bipyridium, dinitroaniline, Aromatic carboxylic acid-based, imidazolinone-based, fatty acid-based, organophosphorus-based, amino acid-based, diphenyl ether-based, nitrile-based herbicides can be mentioned, and plant growth regulators include, for example, ethylene-based, auxin Plant growth regulators, such as a plant, cytokinin, and gibberellin.

  Examples of insecticides include organic phosphorus, carbamate, chloronicotinyl, phenylpyrazole, nereistoxin, and benzoylphenylurea insecticides, natural insecticides, acaricides, and nematicides. An agent etc. can be mentioned.

  As the disinfectant, for example, inorganic copper, organic copper, inorganic sulfur agent, organic sulfur agent, organic phosphorus, benzimidazole, dicarboximide, acid amide, triazole, imidazole, methoxyacrylate, Examples include strobilurin-based, anilinopyrimidine-based, dithiolane-based, quinoxaline-based, aminopyrimidine-based, phenylpyrrole-based, triazine-based, cyanoacetamide-based, gnidine-based bactericides, antibiotic-based bactericides, and natural bactericides. .

  More specifically, as the pesticidal active ingredient (a), for example, benzofenap, benzobicyclone, cumylron, mefenacet, fentrazamide, bromobutide, chromemeprop, eprocarb, pyributicalb, cihalohopbutyl, fenfentrol, pyrazolate, pyrazoxifene, pyri Examples include minobacmethyl, oxadichromemephone, pentoxazone, pyridalyl, etofenprox, fipronil, carbosulfuran, cycloproton, buprofezin, bensultap, dichromedin, tifluzamide, carpropamide, etc., especially benzophenap, benzobicyclon, and cumyluron. It is.

  Furthermore, for example, it is described in documents such as “Agricultural Chemicals Handbook 2005” (issued in October 2005 by the Japan Plant Protection Association), “The Pesticide Manual Threshold Edition” (issued by the British Crop Protection Council 2003), 20 Agrochemicals whose solubility in water at 5 ° C. is 5 ppm or less can also be used as the agrochemical active ingredient (a) of the present invention. These pesticidal active ingredients can be used alone or in combination of two or more.

  The content of the pesticidal active ingredient (a) in the pesticidal granules of the present invention is not particularly limited and can be changed according to the type of the pesticidal active ingredient, but generally based on the weight of the pesticidal granules. It can be 0.1 to 80% by weight, preferably 0.5 to 50% by weight.

  The water surface-floating carrier (b) used in the granule of the present invention has an apparent specific gravity of 0.02 to 0.20, particularly 0.04 to 0.09, a particle size of 100 to 2000 μm, particularly 250 to 1000 μm and Solid powder having a floating rate of 70% or more, particularly 90% or more after 2 hours, such as foamed shirasu, fired vermiculite, foamed pearlite, cork, etc., and these are used alone or in combination of two or more. be able to. The content of the water-floating carrier (b) in the granules of the present invention is not particularly limited, but is generally 0.1 to 8% by weight, preferably 0.1 to 5% by weight, based on the weight of the agricultural chemical granules. %. Here, the “apparent specific gravity” is a value measured by the method according to the Ministry of Agriculture and Water Notification No. 71 of February 3, 1960, and the “grain size” is the method according to the method of Notification No. 750 of the Ministry of Agriculture and Water on July 25, 1982. It is a measured value, and the “floating rate” is a constant amount of particles placed in a container containing distilled water and stirred, and then the weight of the floating particles is measured and the particles used in the measurement are measured. This is the ratio of suspended particles to weight.

  In the present invention, the tripolyphosphate (c) is used for the purpose of improving the dissolution of the agrochemical active ingredient (a), which is hardly soluble in water and the disintegration of grains, into the water. Examples of the form include alkali metal salts such as sodium salt and potassium salt of tripolyphosphoric acid, and these tripolyphosphates can be used alone or in combination of two or more. The content of the tripolyphosphate (c) in the granules of the present invention is not particularly limited, but is generally 0.1 to 10% by weight, preferably 0.5 to 5% by weight, based on the weight of the agricultural chemical granules. It can be.

  In the present invention, the alkylbenzene sulfonate (d) is used for the purpose of improving the dispersibility in water of the pesticidal active ingredient (a), which is hardly soluble in water, and usually has a cationic surface activity. Alkylbenzene sulfonates having 5 to 50 carbon atoms in the alkyl moiety and their blends, which are used as agents, can be used. Specifically, for example, dodecylbenzene sulfonate, polyoxyalkylene allyl phenyl ether Examples thereof include sulfate ammonium salt / alkylbenzene sulfonate, polyoxyethylene alkyl ether / sorbitan fatty acid ether / alkylbenzene sulfonate, and the like. Examples of the salt form include alkali metal salts such as sodium salt and potassium salt, and ammonium salts. These alkylbenzene sulfonates can be used alone or in combination of two or more. The content of the alkylbenzene sulfonate (d) in the granules of the present invention is not particularly limited, but is generally 0.1 to 10% by weight, preferably 0.2 to 5% by weight, based on the weight of the agricultural chemical granules. %.

In the present invention, the carrier (e) other than the above includes water-soluble and water-insoluble solid powders usually used as carriers in the field of agrochemical formulation. Specifically, examples of the water-soluble carrier include , Potassium chloride, urea, ammonium sulfate, sodium sulfate, sodium bicarbonate, glucose, sucrose, fructose, lactose, etc. Examples of water-insoluble carriers include clay, bentonite, talc, calcium carbonate, sodium carbonate, and sieg. Inorganic carriers such as wright, sericite, acid clay, quartzite, diatomaceous earth, pumice, zeolite, vermiculite, white carbon, perlite, attapulgite; organic carriers such as octenyl succinate starch ester, glucose, maltose, sucrose, lactose it can. These carriers can be used alone or in combination of two or more. The content of these carriers (e) is not particularly limited, but is generally 0.1 to 90% by weight, preferably 1 to 70% by weight, based on the weight of the agricultural chemical granules.

  In addition to the above-described components, the agrochemical granule according to the present invention includes, as an optional component, for example, for the purpose of improving the control effect and / or widening the types of pests or weeds to be controlled. Thus, if necessary, other agrochemical active ingredients, surfactants, binders, adjuvants and the like can be included.

  Examples of the other pesticidal active ingredients include pesticidal active ingredients that can be used as herbicides, insecticides, fungicides, etc., having a solubility in water at 20 ° C. of more than 5 ppm, preferably 10 ppm or more.

  The above surfactants are used for the purpose of accelerating the wetting and disintegration of grains, the suspension and dispersion of agrochemical active ingredients in water, or the granulation properties when granulating powder raw materials to prepare granules. An anionic surfactant, a cationic surfactant, a nonionic surfactant, a silicone-based surfactant, or a fluorine-based surfactant can be used for the purpose of improving the resistance.

  Examples of the anionic surfactant include alkyl naphthalene sulfonate, naphthalene sulfonate formalin condensate, dialkyl sulfosuccinate, lignin sulfonate, α-olefin sulfonate, polystyrene sulfonate, and alkyl ether sulfate salt. , Polyoxyethylene alkyl ether sulfate salts, fatty acid salts, isobutylene-maleic acid copolymer salts, styrene-maleic acid copolymer salts, polyacrylic acid salts, and the like. Acid salts, dialkyl sulfosuccinates, alkyl naphthalene sulfonates, lauryl sulfates and the like. Nonionic surface activity includes polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene still phenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl amine and the like.

  The above-mentioned binder is usually used for the purpose of imparting hardness to the granules when granulating powder raw materials to prepare granules, for example, starch, reduced starch saccharified product, dextrin, cellulose, Methyl cellulose, ethyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl starch, pullulan, sodium alginate, ammonium alginate, guar gum, locust bean gum, gum arabic, xanthan gum, gelatin, casein, polyvinyl alcohol, polyethylene glycol, ethylene / propylene block polymer, poly Examples include sodium acrylate.

  Examples of the auxiliary agent include stabilizers such as antioxidants, ultraviolet ray inhibitors and crystal precipitation inhibitors; antiseptics such as sorbic acid, potassium sorbate, p-chloro-m-xylenol, and butyl p-oxybenzoate. Antibiotics; pH adjusters such as citric acid, phosphoric acid, and magnesium carbonate.

  The above-mentioned optional components can be used alone or in combination of two or more, and the blending amount in the granules of the present invention is not particularly limited, but is usually 0.1 based on the weight of the agricultural chemical granules. -80% by weight, preferably 0.5-50% by weight.

  The agrochemical granule of the present invention can be prepared by a granulation method usually used in the formulation of agrochemicals. Examples of the granulation method include extrusion granulation method, rolling granulation method, and rolling fluid granulation. Method, fluidized bed granulation method, compression granulation method, stirring and mixing granulation method, coating granulation method, tableting method and the like, generally, extrusion granulation method is preferred, specifically, For example, it can be granulated as follows. Agrochemical active ingredient (a) having a water solubility at 20 ° C. of 5 ppm or less, water surface-floating carrier (b), tripolyphosphate (c), alkylbenzenesulfonate (d) and other carriers (e), and any of the aforementioned The ingredients (at least one of other agrochemical active ingredients, surfactants, carriers, binders and adjuvants) are mixed, the mixture is hydro-kneaded, and the extrusion hole diameter (screen diameter) is 0.3 to 5 mm. Granulate with an extrusion granulator adjusted within the range. The obtained granules are sized with a Malmerizer, dried, and sieved to obtain the agrochemical granules of the present invention.

  The agrochemical granule of the present invention obtained by the above granulation method can usually have an average particle size in the range of 0.5 to 3 mm, preferably 0.5 to 2.0 mm.

  The agricultural chemical granules provided by the present invention can be applied to paddy fields in the same manner as ordinary agricultural chemical granules. Application to paddy fields can be performed using, for example, hand granulation, human-powered or powered granulation, a wireless induction unmanned helicopter, or the like.

  The application amount to the paddy field is not particularly limited, and is generally 100 g to 3 kg per 10 a, preferably 200 g to 1 kg per 10 a from the labor-saving viewpoint.

  EXAMPLES Hereinafter, although an Example and a test example demonstrate this invention further more concretely, this invention is not limited only to these Examples and a test example.

Example 1
4. Pyraclonil base 2.19% by weight, benzobicyclon base 2.21% by weight, benzophenap base 8.64% by weight, polyoxyalkylene allyl phenyl ether sulfate ammonium salt / alkylbenzenesulfonic acid metal salt combination product 0% by weight, carboxymethyl cellulose 8.0% by weight, octenyl succinic acid starch ester 15.0% by weight, sodium tripolyphosphate 10.0% by weight, cork 3.0% by weight and calcium carbonate 45.96% by weight in a mixing container. The mixture is mixed for 5 minutes with a universal mixer, and 13% by weight of water is added to 100% by mass of the mixture, and then kneaded for 5 minutes. This kneaded product is granulated with a basket type granulator (produced by Hata Iron Works Co., Ltd.) equipped with a 1.2 mm diameter screen, the granulated particles are dried, and the obtained particles are sieved (2. 38 to 0.21 mm) to obtain an agrochemical granule.

Example 2
1.95% by weight of Pyraclonil base, 15.5% by weight of Cumyllon base, 1.3% by weight of sodium dodecylbenzenesulfonate, 4.0% by weight of propylene glycol monophenyl ether, 2.0% by weight of sodium tripolyphosphate, Cork 2.0% by weight, 30.0% by weight bentonite and 43.25% by weight calcium carbonate are weighed in a mixing container and mixed for 5 minutes in a universal mixer. 12% by weight of water is added to 100% by weight of this mixture. After the addition, knead for an additional 5 minutes. This kneaded product is granulated with a basket type granulator (produced by Hata Iron Works Co., Ltd.) equipped with a 1.2 mm diameter screen, the granulated particles are dried, and the obtained particles are sieved (2. 38 to 0.21 mm) to obtain an agrochemical granule.

Comparative Example 1
4. Pyraclonil base 2.19% by weight, benzobicyclon base 2.21% by weight, benzophenap base 8.64% by weight, polyoxyalkylene allyl phenyl ether sulfate ammonium salt / alkylbenzenesulfonic acid metal salt combination product 0% by weight, carboxymethyl cellulose 8.0% by weight, octenyl succinic acid starch ester 15.0% by weight, sodium tripolyphosphate 10.0% by weight and calcium carbonate 48.96% by weight are weighed in a mixing vessel Mix for 5 minutes, add 13.0% by weight of water to 100% by weight of the mixture and knead for 5 minutes. This kneaded product is granulated with a basket type granulator (produced by Hata Iron Works Co., Ltd.) equipped with a 1.2 mm diameter screen, the granulated particles are dried, and the obtained particles are sieved (2. 38 to 0.21 mm) to obtain an agrochemical granule.

Comparative Example 2
1.95% by weight of Pyraclonil base, 15.5% by weight of Cumyllon base, 1.3% by weight of sodium dodecylbenzenesulfonate, 4.0% by weight of propylene glycol monophenyl ether, 2.0% by weight of sodium tripolyphosphate, bentonite 30.0 wt% and calcium carbonate 45.25 wt% were weighed into a mixing vessel, mixed for 5 minutes with a universal mixer, 12 wt% water was added to 100 wt% of this mixture, and then for another 5 min Knead. This kneaded product is granulated with a basket type granulator (produced by Hata Iron Works Co., Ltd.) equipped with a 1.2 mm diameter screen, the granulated particles are dried, and the obtained particles are sieved (2. 38 to 0.21 mm) to obtain an agrochemical granule.

  Next, the agricultural chemical granules prepared in Examples 1 and 2 and the agricultural chemical granules prepared in Comparative Examples 1 and 2 were evaluated by the methods described in the following test examples.

Test example 1 (water dissolution test)
In a 500 ml beaker, 250 ml of 3 degree hard water at 20 ° C. is added, and 20 mg of each agricultural chemical granule prepared above is added. Take 1 ml from the center of the beaker after 0.5, 2 and 24 hours. In addition, after collecting water after 24 hours, 1 ml of water is collected by sufficiently dispersing the agrochemical active ingredient with an ultrasonic wave together with the beaker. The concentration of the pesticidal active ingredient in these collected samples was measured by liquid chromatography, and the elution rate in water was calculated using the following formula (1). The results are shown in Table 1.
Elution rate in water (%) = (Ct / Cx) × 100 (1)
Where
Ct is the concentration of the pesticidal active ingredient 0.5 hours, 2 hours and 24 hours after spraying,
Cx is the concentration of the pesticidal active ingredient when the beaker is fully dispersed with ultrasound.

  According to the results of Table 1 above, benzobicyclon, benzophenap and cumylron, which are pesticidal active ingredients having a water solubility of 5 ppm or less in the granules of Example 1 and Example 2, are shown in Comparative Example 1 and Comparative Example 2. Compared with the same component in the granule, it is observed that it is quickly eluted in water.

Test example 2 (herbicidal test)
Fill the paddy soil in 1/2000 ares, add appropriate amount of water and chemical fertilizer and knead. After clear water, plant 3 urikawa tubers and appropriate amount of firefly seeds. Transplanted. The pot was kept flooded at a depth of 5 cm and placed in a glass chamber with an average temperature of 25 ° C. Then, when firefly started to emerge, each agrochemical granule of the example or the comparative example was processed into a pot so as to have a predetermined dose per 10 ares. Three weeks after the treatment, weeding effects of weeds and phytotoxicity against rice were investigated. The evaluation of the herbicidal effect is shown in the following 6 stages according to the state of the untreated section and the growth inhibition rate (%).
0: 0% to less than 20%,
1: 20% to less than 40%,
2: 40% to less than 60%,
3: 60% or more and less than 80%,
4: 80% to less than 100%,
5: 100%

Moreover, the evaluation of the phytotoxicity against rice is shown in the following 6 stages as compared with the state of the untreated section.
0: Normal growth,
1: Slight harm,
2: Small harm,
3: Harm,
4: Major harm,
5: Complete death

The results are shown in Table 2.

  According to the results in Table 2 above, the granule of Example 1 has a higher herbicidal effect on Urikawa and Firefly as compared to the granule of Comparative Example 1, and the granule of Example 2 is Comparative Example 2. Higher herbicidal effect was observed in firefly than in other granules. In addition, no phytotoxicity was observed on rice with any of the reagent agents.

Claims (5)

  (A) Agrochemical active ingredient whose water solubility at 20 ° C. is 5 ppm or less, (b) Apparent specific gravity is 0.02 to 0.20, particle size is 100 to 2000 μm, and floating rate after 2 hours is 70% or more. An agrochemical granule having improved water-dissolving properties, comprising a water surface-floating carrier, (c) tripolyphosphate, (d) alkylbenzene sulfonate, and (e) another carrier.   The agrochemical active ingredient (a) is at least one selected from benzophenap, benzobicyclon, and cumylron, and the content thereof is 0.1 to 80% by weight based on the weight of the agrochemical granule. Agrochemical granules described in 1.   The water-floating carrier (b) is at least one selected from foamed shirasu, calcined vermiculite, foamed perlite and cork, and the content thereof is 0.1 to 8% by weight based on the weight of the agricultural chemical granule. Item 3. Agrochemical granule according to item 1 or 2.   The agrochemical granule according to any one of claims 1 to 3, wherein the average particle size is 0.5 mm to 3 mm.   The agrochemical granule according to any one of claims 1 to 4, which is applied to a paddy field.