JP4993842B2 - High concentration granule wettable powder for herbicidal use - Google Patents

Description

The present invention relates to a high-concentration granular wettable powder for herbicidal which is excellent in dispersibility and suspension in water and is safer and easier to handle.

In recent years, a safer and easier-to-handle agricultural chemical formulation has been attracting attention due to environmental problems of agricultural chemicals and a shortage of agricultural workers. Therefore, there is a demand for safe and easy-to-handle agents for farm workers. By reducing the amount of organic solvents and increasing the concentration of active ingredients in the agent, it is safe and high in concentration. The method is taken. Furthermore, the high-concentration agent requires less amount when sprayed than the low-concentration agent, and is excellent in transportation and storage. Examples of agents that satisfy these requirements include wettable powders, granular wettable powders, flowable agents, emulsion agents, and suspoemulsion agents.

A wettable powder is a powder in which active ingredients, surfactants (wetting agents, dispersants) and extenders are mixed, and a wide range of agrochemicals can be formulated at a high concentration, thus reducing transportation and storage costs. . However, since it is fine powder, powdering occurs when handling or opening the package, there is a risk that the operator may be exposed to the chemicals, and the measuring work is inconvenient. A flowable agent is obtained by suspending a solid active ingredient in water, and an active ingredient, a surfactant, and a thickener previously ground are used. The flowable agent does not use an organic solvent and is free from powdering like a wettable powder, so it is safe and easy to measure for the operator. However, because of its relatively high viscosity, it is inconvenient to take out from the container, and there is a problem of disposal of used containers due to adhesion in the container, and the total weight of the agent increases due to the inclusion of water. There are problems that transportation becomes inconvenient, and solid matter settles down during storage for a long period of time, making it difficult to use. Emulsion is an active ingredient insoluble in water added to an emulsifier and emulsified and dispersed as fine particles in water. Suspoemulsion disperses a suspension in which a solid active ingredient is dispersed and a liquid active ingredient. However, both have the same disadvantages as the flowable agent described above.

In recent years, granule wettable powder has attracted attention in order to solve the above problems. Granule wettable powder is a granular preparation that rapidly disintegrates and disperses when introduced into water. Also called dry flowable, it is a granulated solid content of wettable powder or flowable. As a general feature of granule wettable powder, it is granulated and safe for workers, and its apparent specific gravity is large, so packaging is small and advantageous for transportation and storage. Compared to wettable powder It is easy to handle because of its good fluidity, and it is possible to prepare a high concentration preparation.

On the other hand, paying attention to the relationship between the formulation and the herbicide active ingredient as shown above, taking DCMU [3- (3,4-dichlorophenyl) -1,1-dimethylurea] as an example , DCMU is widely used as a herbicide regardless of agricultural land (field, paddy field) and non-agricultural land (park, railway, residential land), and is used as a powder, granule, fine granule, flowable, wettable powder, etc. ing. Among them, DCMU high concentration agents include wettable powders and flowable agents (sol agents). However, both of these agents have the disadvantages described above, and they are liable to settle after being suspended in water, and the precipitates are likely to aggregate, which has caused nozzle clogging of the sprayer. These disadvantages are not limited to DCMU, and are common features in the case of herbicidal active ingredients having highly cohesive properties.

When making a granular wettable powder using a herbicide active ingredient having high cohesive properties such as DCMU, this point must be particularly noted. That is, the rapid solidification of the solid content after the agent is dispersed in water and the ease of aggregation of the precipitates are barriers to commercialization. Therefore, the development of a new formulation such as a granular wettable powder that has solved these disadvantages is awaited.

As a method for solving these problems, a method has been proposed in which an active ingredient of a herbicide is pulverized to make it difficult to settle, and a coagulation property is reduced by adding a large amount of inorganic substances (for example, Patent Document 1). In order to use a large amount of salt and mineral, on the contrary, the amount of herbicide active ingredient added must be reduced, so that a high concentration could not be realized.

JP-A-57-81403

Granule wettable powder is a granulated solid content of wettable powder and flowable powder. In general, the content of a solid active ingredient can be up to about 90%. However, the active ingredient content often has to be reduced due to the properties of the active ingredient. That is, when the cohesiveness of the active ingredient is high or the melting point is low, it must be formulated by adding timely materials. Therefore, in reality, it is difficult to make the content 90%, and the content must be less than that. Many commercially available granule wettable powders are 60% or less. There are some high-concentration granular wettable powders of 70% or more, but there are complaints such as nozzle clogging easily occurring during spraying, and there is room for improvement. Therefore, since a high-concentration granular wettable powder that reduces the amount of materials as much as possible and does not cause nozzle clogging is desired, the present inventors have developed a high-concentrated granular wettable powder containing 50% or more of the active ingredient. I made it.

The present invention relates to a high-concentration granular wettable powder that is safe and easy to handle for workers, is excellent in water dispersibility and suspension, and uses a herbicide active ingredient that has high cohesive properties. The purpose is to provide.

The inventors of the present invention have made granulation wettable powders of active ingredients with high concentration of granule wettable powder, particularly herbicide active ingredients having particularly high cohesive properties, easy to granulate, dispersibility of the agent in water, suspension. As a result of studying an agent that is excellent in properties and difficult to reaggregate after dispersion, the herbicide active ingredient is finely pulverized to an average particle size of d = 4 to 12 μm , an inorganic salt, a dispersant, a wetting agent, It discovered that the target agent was obtained by adding and mixing minerals, such as a viscosity, and carrying out extrusion granulation, and came to complete this invention.

That is, the present invention contains a herbicide active ingredient whose average particle size is controlled to 4 to 12 μm, and contains an inorganic salt or an organic salt as an auxiliary agent. It is. Further, the present invention is characterized in that the herbicide active ingredient whose particle size is controlled is obtained by pulverizing the herbicide active ingredient. Furthermore, the present invention is characterized in that the herbicide active ingredient described above is a herbicide active ingredient having high cohesive properties.

Further, the high-concentration granular wettable powder for herbicidal use according to the present invention contains 0.1 to 20%, preferably 1 to 10%, of the inorganic salt or organic salt content of the adjuvant relative to the high-concentrated wettable powder wettable powder. %, More preferably 3 to 7%. Further, the high-concentration granular wettable powder for herbicidal use according to the present invention is characterized in that the content of the herbicidal active ingredient is 50% by mass or more based on the high-concentrated granular wettable powder for herbicide.

As one of the herbicide active ingredients used in the present invention, attention is focused on 3- (3,4-dichlorophenyl) -1,1-dimethylurea (hereinafter referred to as DCMU), which is 50% or more, preferably 60% or more. Further, the average particle size was controlled to 4 to 12 μm with the aim of a granular wettable powder containing 70% or more. Naturally, the physical properties of the agent are greatly affected by the herbicide active ingredient, in this case DCMU. DCMU without particle size control has an average particle size of 13 to 21 μm, so it can easily settle even when suspended in water using a wetting agent, etc. Also, the precipitate is viscous and inferior in redispersibility, and is dispersed. This may cause clogging of the machine nozzles and hoses. In the high-concentration granular wettable powder for herbicidal use according to the present invention, DCMU was finely pulverized to reduce the sedimentation rate in water and improve the suspension property.

Here, in order to explain the improvement of the present invention, the relationship between the particle size of the high-concentration granular wettable powder for herbicidal use and the dilatancy will be described. As an example of dilatancy, if you step on the sand where water emerges at the beach, the surrounding area suddenly hardens and the water seems to dry, but when you lift your foot, it returns to its original state. It is done. This phenomenon does not occur only with special materials, but can also be seen with general materials, but it tends to depend on the size and specific gravity of the particles, the viscosity of the liquid, and the ratio, and occurs in a very narrow range where these conditions are met. It is said. Even with DCMU, when the average particle size d <4 μm, this phenomenon occurs remarkably during kneading granulation with a wetting agent and water.

Referring to FIG. 1, in FIG. 1A, DCMU particles are in a finely packed state, and in such a case, since there are few voids between the particles, moisture is expelled to the outside of the particles. It exudes to the surface and becomes a highly viscous substance. When an external force is applied to this during granulation, the particle arrangement is changed as shown in (B) of FIG. 1 and the volume is increased, and moisture enters the surface to dry the surface. However, when external force is no longer applied, it reverts to [FIG. 1] (A) again, and moisture oozes again on the surface. Therefore, even if extrusion granulation is performed in the state of [FIG. 1] (B), the agent will be rebound to become [FIG. 1] (A) thereafter. The reason for this phenomenon is that (1) the surface is slippery, (2) the content of the target particles is high, (3) the particle diameter is uniform (the particle size distribution is narrow), and (4) the specific gravity of the particles is There are small things.

As a method for preventing this fine packing state, (1) reduce the amount of wetting agent to make the surface difficult to slip, (2) increase the amount of addition of minerals other than DCMU, (3) particle size distribution (4) It is conceivable to increase the average particle size in order to increase the specific gravity of the particles. However, in making the agent of the present invention, (1) weight loss of the wetting agent makes the water dispersibility of the agent inferior, and (2) because the content of DCMU is high, the content of other components such as minerals is significantly restricted. (3) If the particle size distribution is extremely widened, there may be harmful effects such as large particles increasing and settling easily. (4) The average particle size should be increased without widening the particle size distribution. It is considered optimal. Accordingly, in the present invention, a condition in which the average particle diameter is set to d = 4 to 12 μm by pulverizing DCMU is employed in order to prevent the occurrence of dilatancy and to prevent the sedimentation even after water dispersion.

DCMU used in the present invention is also a herbicide active ingredient having low water solubility, and stabilization of uniform dispersion in water is important. Also in the present invention, when a granulated wettable powder made of DCMU, a wetting agent, a dispersant, and a mineral is made, DCMU is uniformly dispersed immediately after the agent is added to water, but then DCMU begins to aggregate. Aggregates of about 1 mm are produced. When this agglomerate is generated, there is a possibility of clogging the nozzle part of the spreader.

A solid-liquid dispersion in which fine particles are suspended is thermodynamically unstable and always aggregates to try to reduce the surface area. This is because when solid particles are dispersed in a liquid, the particle surface is charged due to the presence of dissociation groups on the particle surface, adsorption of ions, defects on the solid surface, and the like, and positively charged particles and negatively charged particles are easily bonded. In order to prevent this, a method of controlling the surface charge amount by adding an ionic substance (electrolyte) or providing a protective colloidal role by adding a polymer ionic substance is employed. The herbicide active ingredient having high cohesive properties of the present invention was also improved by adding an ionic substance while selecting the type and amount of the ionic substance.

The herbicide active ingredient is finely pulverized to control the average particle size to 4 to 12 μm, and the herbicide active ingredient having high cohesive properties by adding an auxiliary agent can be dispersed and suspended. And an agent in which the herbicidal active ingredient in the suspension does not aggregate can be produced. Thereby, a safe and easy-to-use agent can be provided to the worker. In addition, the cost of the agent can be reduced because it is produced by the extrusion granulation method.

Hereinafter, the constituent components and the production method of the present invention will be specifically described. For pulverizing DCMU, a dry pulverizer such as a jet mill pulverizer or a high-speed impact mill such as a hammer mill or a pin mill is suitable. At this time, when the pulverization property is deteriorated due to the adhesion of DCMU inside the apparatus, a pulverization aid such as white carbon, clay, diatomaceous earth or the like may be added and pulverized. The average particle diameter of DCMU pulverized by such a pulverizer is preferably d = 4 to 12 μm.

When the average particle size is larger, when the granular wettable powder is dispersed in water, DCMU has poor suspension and settles in a short time. On the other hand, when the average particle size is smaller than this, the dilatancy phenomenon is caused when adding and kneading and granulating, and granulation becomes extremely difficult. Furthermore, regarding the granulated wettable powder after granulation, since the cohesiveness between particles becomes strong, the disintegration of the agent in water does not proceed rapidly and the dispersibility is poor.

The electrolyte is not particularly limited as long as it is an inorganic salt, and is not affected by valence, molecular weight or the like. Inorganic salts include magnesium sulfate , sodium chloride, ammonium chloride, potassium chloride and the like. The addition amount is suitably 1 to 10% as an inorganic salt.

In the present invention, addition of the organic salt is not limited. Sodium acetate is mentioned as an organic salt, and the addition amount is suitably 1 to 10% as an organic salt. Other organic salts include polycarboxylic acid sodium salt, polyoxyethylene lauryl ether sulfate sodium salt, coconut oil fatty acid methyl taurine sodium, alkyl allyl sulfonate, dialkyl ester sulfonate, alkenyl sulfonate salt, and other various organic electrolytes. These organic salts are used at 1-15% .

The method for adding the electrolyte is not particularly limited. When the electrolyte is a solid, it may be added simultaneously with the mixing of the raw material powder or may be added after being dissolved in kneading water. When the electrolyte is liquid, it may be added after mixing the raw material powder and simultaneously with other liquid components (wetting agent or the like) or dissolved in kneading water.

As the electrolyte used in the present invention, magnesium sulfate and sodium acetate are preferable.

The surfactant used in the present invention is not particularly limited, and is a general nonionic surfactant, anionic surfactant, or cationic surfactant used in granule wettable powder, granule, wettable powder. Surfactants can be used, and these may be used alone or in combination of two or more.

Nonionic surfactants include polyoxyethylene lauryl ether, polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene aryl phenyl ether, and polyoxyethylene fatty acid ester.

Anionic surfactants include lignin sulfonate, alkyl allyl sulfonate, dialkyl ester sulfonate, alkenyl sulfonate salt, alkyl sulfate, alkyl benzene sulfonate, polyoxyethylene alkyl ether sulfate, polycarboxylate, naphthalene Examples include sulfonates, coconut oil fatty acid methyl taurine sodium, and higher fatty acid salts. Examples of the cationic surfactant include quaternary ammonium salts and alkylamine salts.

Preferable surfactants used in the present invention are lignin sulfonate, coconut oil fatty acid methyl taurine sodium, alkyl allyl sulfonate, dialkyl ester sulfonate, and alkenyl sulfonate salt.

In the present invention, mineral powder, water-soluble powder, and vegetable powder may be used as a bulking agent and a grinding aid as necessary, and these may be used alone or in combination of two or more. good.

The mineral powder is not particularly limited, and examples thereof include diatomaceous earth, clay, talc, bentonite, calcium carbonate, zeolite, and acid clay.
The water-soluble powder is not particularly limited, and examples thereof include sugars, urea, sulfates, nitrates, phosphates, hydrochlorides, metal salts, and ammonium salts.
Although it does not restrict | limit especially as vegetable powder, Various plant fiber materials, such as wheat flour, a bran, and bran, are mentioned.
As the extender and grinding aid used in the present invention, diatomaceous earth and clay are preferable.

Although the granule wettable powder of this invention is manufactured with the following method, it is an example and is not specifically limited.
First, DCMU is pulverized with a jet mill pulverizer, and the average particle diameter is d = 4 to 10 μm. Subsequently, DCMU and raw material powder (surfactant, electrolyte , extender, etc.) are uniformly mixed. Further, when a liquid component is used, it is dissolved in kneading water, added and kneaded, granulated using an extrusion granulator, and dried to obtain a target product. The electrolyte may be added after being dissolved in kneading water. For the drying, a hot air dryer, a radiation dryer, a heat conduction dryer or the like is used.

The particle size of the intended granular wettable powder thus obtained is 0.2 to 2.0 mm, preferably 0.5 to 1.0 mm.

The obtained granular wettable powder is excellent in (1) water dispersibility and suspension. (2) Since the dispersoid does not agglomerate, nozzle clogging or the like does not occur and can be quickly sprayed. (3) The redispersibility of the sediment after sedimentation is also excellent. It can be used on agricultural land and non-agricultural land.

EXAMPLES Next, although an Example, a comparative example, and a test example are given and this invention is demonstrated further, this invention is not limited to these. In the following examples, “part” represents “part by mass” and “%” represents “mass%”. The average particle diameter is a value measured by a laser diffraction / scattering particle size distribution measuring apparatus.
The raw materials used in the experiment are as follows.
Lignin sulfonate: Toho Chemical Co., Ltd. Sorpol 9047k
Palm oil fatty acid methyl taurine sodium: Toho Chemical Co., Ltd. Neoscope CN-30SF
Alkyl allyl sulfonate: Toho Chemical Co., Ltd. RUNOX P-65L
Dialkyl ester sulfonate: Toho Chemical Co., Ltd. Sorpol 5050
Alkenyl sulfonate 3 parts: Toho Chemical Co., Ltd. Sorpol 5115
Diatomaceous earth: Radiolite # 900, Showa Chemical Industry Co., Ltd.
Clay: manufactured by Katsumiyama Mining Co., Ltd., Katsumiyama clay magnesium sulfate: manufactured by Komune Chemical Co., Ltd., anhydrous magnesium sulfate sodium acetate: Genuine Chemical Co., Ltd. reagent special grade

[Example 1]
70 parts of DCMU, 5 parts of sodium lignin sulfonate, 10 parts of diatomaceous earth, and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle size d = 4 μm, were mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

70 parts of DCMU, 5 parts of sodium lignin sulfonate, 10 parts of diatomaceous earth, and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle size d = 10 μm, were mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

70 parts of DCMU, 5 parts of sodium lignin sulfonate, 3 parts of alkyl allyl sulfonate, 10 parts of diatomaceous earth and 5 parts of magnesium sulfate were added and mixed uniformly. Thereafter, 7 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

70 parts of DCMU, 5 parts of sodium lignin sulfonate, 3 parts of dialkyl ester sulfonate, 10 parts of diatomaceous earth, and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle diameter d = 4 μm, were mixed uniformly. Thereafter, 7 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

70 parts of DCMU, 5 parts of sodium lignin sulfonate, 3 parts of alkenyl sulfonate, 10 parts of diatomaceous earth and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle size d = 4 μm, were mixed uniformly. Thereafter, 7 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

70 parts of DCMU, 5 parts of sodium lignin sulfonate, 10 parts of diatomaceous earth and 5 parts of sodium acetate, which were pulverized by a jet mill pulverizer to an average particle diameter d = 4 μm, were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

70 parts of DCMU, 5 parts of sodium lignin sulfonate, 10 parts of clay and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle size d = 4 μm, were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

50 parts of DCMU, 5 parts of sodium lignin sulfonate, 30 parts of diatomaceous earth and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle size d = 4 μm, were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

60 parts of DCMU, 5 parts of sodium lignin sulfonate, 20 parts of diatomaceous earth, and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle size d = 4 μm, were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

[Comparative Example 1]
70 parts of DCMU, 5 parts of sodium lignin sulfonate, 10 parts of diatomaceous earth and 5 parts of magnesium sulfate, which were pulverized by a jet mill pulverizer to an average particle diameter d = 2 μm, were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

[Comparative Example 2]
70 parts of unpulverized DCMU (average particle size 15 μm) without jet mill pulverization, 5 parts of sodium lignin sulfonate, 10 parts of diatomaceous earth, and 5 parts of magnesium sulfate were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

[Comparative Example 3]
70 parts of DCMU, pulverized with a jet mill pulverizer to an average particle diameter d = 4 μm, 5 parts of sodium lignin sulfonate, and 15 parts of diatomaceous earth were added and mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

[Comparative Example 4]
70 parts of DCMU, 5 parts of sodium lignin sulfonate, 5 parts of alkenyl sulfonate and 10 parts of diatomaceous earth, which were pulverized by a jet mill pulverizer to an average particle size d = 4 μm, were mixed uniformly. Thereafter, 10 parts of a 29% aqueous solution of coconut oil fatty acid methyl taurine sodium salt as a sodium salt was added and kneaded, and granulated using an extrusion granulator equipped with a screen having a pore diameter of 0.7 mm. Thereafter, it was dried at 60 ° C., sieved and sized to obtain the desired product.

[Comparative Example 5]
Commercially available DCMU 80% wettable powder "Dyrone wettable powder"
A powder comprising 80% unground DCMU (average particle size 15 μm), 20% surfactant and mineral fine powder.

[Test Example 1] Water dispersibility / suspension test 100 ml of standard hard water at 25 ° C. was placed in a 100 ml stoppered graduated cylinder, and 1 g of a sample was placed therein and allowed to stand for 1 minute. Thereafter, the measuring cylinder was inverted at a rate of 2 times / minute, and the number of times required until the sample was uniformly dispersed was measured. Furthermore, after leaving still for one day, the graduated cylinder was inverted again, and the number of times until the precipitate was redispersed was measured.
Further, the sample was uniformly dispersed by the same method and allowed to stand. After 30 minutes, 4 ml was collected from the center of the cylinder, and DCMU components were analyzed by high performance liquid chromatography to obtain a suspension rate. In addition, the suspension rate was calculated | required with the following formula | equation.
Suspension rate (%) = [(A × 25) / B] × 100
A: DCMU content in the collected solution B: Theoretical value when DCMU is uniformly dispersed (initial DCMU amount)
The test results are shown in [Table 1].
The smaller the “number of times required for uniform dispersion”, the better the dispersibility, and the higher the suspension rate, the better the suspension.

As apparent from [Table 1], in Examples 1 to 9, by providing a DCMU average particle diameter d = 4 to 12 μm, a particle diameter range is provided, and an agent excellent in dispersibility and suspension at a DCMU concentration of 50% or more We were able to. On the other hand, in Comparative Example 1 having a DCMU particle size of 2 μm, the suspension is good, but the dispersibility is remarkably inferior. In Comparative Example 2 having a DCMU particle size of 15 μm, the dispersibility is good, but the suspension property is inferior. In Comparative Example 3 containing no magnesium sulfate or the like, the number of times required for uniform dispersion was the same as in Examples, but reaggregation was observed immediately after uniform dispersion, which deteriorated the suspension rate. That is, it can be seen that the suspension can be improved by adding magnesium sulfate. Since the wettable powder of Comparative Example 5 was a powder, the number of times required for uniform dispersion was small. However, since the DCMU particle size was 10 μm or more, the suspension rate was poor as in Comparative Example 2.

[Test Example 2] Cohesiveness test The sample was uniformly dispersed by the same method as in Test Example 1 to prepare a suspension. The suspension was filtered using a filter paper, and a residue (solid component of the sample) was formed on the filter paper. Got. After the residue was dried, the presence or absence of aggregates of about 1 mm was examined to evaluate the cohesiveness. When this agglomerate is large, it causes nozzle clogging at the time of spraying. The test results are shown in [Table 2].

In Comparative Example 3 and Comparative Example 4 that did not contain magnesium sulfate or the like, aggregates were observed. It can be seen that the addition of magnesium sulfate and sodium acetate has an effect on the uniformity (aggregation) of the dispersoid.

[Test Example 3] 15 drainage holes of about 5 mm were made in the bottom of the biological evaluation soot pack, and soil was put in the pack to make a test section.
Next, 20 seeds of various weeds (Enocologosa, Agaricus, Nobier, Aobiu, Kosendangusa, Yabasou) were sprayed on the pack.
A test sample was sprayed on the sample at a ratio of 50 g / 10a, 75 g / 10a, 100 g / 10a, and 150 g / 10a.
The spraying time of the test sample was distinguished from “weed generation pretreatment” when sprayed at the same time as the seed, and “weed generation initial treatment” after 19 days after confirming that weeds had grown.
After the experiment was started, weeds were evaluated by comparing the occurrence of weeds 24 and 45 days later.

(How to read the table)
Judgment is made by a five-step evaluation. 5 means the highest effect, meaning that all the target weeds are withered, and 0 means no effect at all. In general, it is known that increasing the amount of treatment increases the effect, and the difference in the effect becomes clear as the number of days passes.
[Weed generation pretreatment]
[Table 3] shows the results of biological evaluation by pretreatment of weeds. The evaluation for each weed is as follows.

Enokorogusa: Example 1, Comparative Example 5> Comparative Example 2> Comparative Example 1
Barb: Example 1, Comparative Example 1, Comparative Example 5> Comparative Example 2
Nobie: Comparative Example 1> Example 1, Comparative Example 5> Comparative Example 2
Aubiille: There was no significant difference between the formulations.
Yabusaw: Example 1, Comparative Example 1, Comparative Example 5 ≧ Comparative Example 2
Kosendangusa: There were no significant differences between formulations.
From the above results, it was found that in the pretreatment for weed generation, Example 1 showed a high herbicidal effect equivalent to that of Comparative Example 5 which is a commercial product.

[Weed generation initial treatment]
[Table 4] shows the results of biological evaluation by the weed generation initial treatment. The evaluation for each weed is as follows.

Enokorogusa: Comparative Example 2> Example 1> Comparative Example 1> Comparative Example 5
Barb: Example 1, Comparative Example 1 ≧ Comparative Example 2, Comparative Example 5
Nobie: Example 1> Comparative Example 1, Comparative Example 2, Comparative Example 5
Aubiille: There was no significant difference between the formulations.
Yabathou: No significant difference was found between the formulations.
Kosendangusa: There were no significant differences between formulations.
From the above results, almost the same effect has been obtained in the initial treatment of weeds. Among them, Example 1 has the highest herbicidal effect compared to Comparative Example 5 which is a commercial product against Gramineae weeds. Indicated.

In the test samples, the same effects as those of Comparative Example 5 which is a commercially available agent are obtained. That is, it means that the particle size of DCMU does not affect biological evaluation. Moreover, about the agent which did not add magnesium sulfate etc. like the comparative examples 3 and 4, since the granular aggregate was clogged with the nozzle of the spreader, it could not be spread and evaluation was not possible. Therefore, it is understood that the granule wettable powder as in Example 1 of the present invention is desirable in consideration of the suspension property and the presence or absence of aggregates.

Even in the case of a herbicide active ingredient having high cohesive properties, when the agent is excellent in dispersibility and suspension and the herbicide active ingredient in the suspension does not aggregate, the high-concentration granule for herbicidal use of the present invention A wettable powder can be applied.

It is explanatory drawing which illustrated the dilatancy.

Explanation of symbols

(A) Finely packed state of particles (B) State in which the arrangement state of particles is changed and the volume is increased

Claims (4)

A high-concentration granular wettable powder for herbicide containing DCMU [3- (3,4-dichlorophenyl) -1,1-dimethylurea] as an active ingredient of herbicide , wherein the herbicide active ingredient is averaged by grinding and the grain diameter control the diameter 4～12Myuemu, obtained by granulation is contained 1 to 10 mass% with respect to the high concentration water-dispersible granules for the herbicide magnesium sulfate or sodium acetate as an adjunct, herbicides effective A high-concentration granular wettable powder for herbicidal use, which contains 50% by mass or more of ingredients. The content of magnesium sulfate or sodium acetate of the above-described auxiliary agent is 3 to 7 wt% with respect to herbicidal high concentration water dispersible granules, the high density water dispersible granule for herbicide according to claim 1. A high-concentration granular wettable powder for herbicide containing DCMU [3- (3,4-dichlorophenyl) -1,1-dimethylurea] as an active ingredient of herbicide , wherein the herbicide active ingredient is averaged by grinding and the grain diameter control the diameter 4～12Myuemu, obtained by granulation is contained 1 to 10 mass% with respect to the high concentration water-dispersible granules for the herbicide magnesium sulfate or sodium acetate as an adjunct, herbicides effective A method for producing a high-concentration granular wettable powder for herbicidal treatment, which contains 50% by mass or more of the components. The method for producing a high-concentration granular wettable powder for herbicidal use according to claim 3 , wherein the content of magnesium sulfate or sodium acetate in the adjuvant is 3 to 7% by mass based on the high-concentrated granular wettable powder for herbicidal use. .

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