JP2001081001A - Aqueous suspension-like herbicidal composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous suspension-like herbicidal composition for solving a problem on the decomposition of active ingredients in preparations. SOLUTION: This aqueous suspension-like herbicidal composition is obtained by including 1-30 wt.% of slightly water-soluble or insoluble one or more than two kinds of herbicidal compounds with a middle particle diameter of 0.5-10 μm, 5-10 wt.% of glycerine and 50-85 wt.% of water. Further, this herbicidal composition contains a surfactant in an amount needed for keeping the composition in a suspended state and has a viscosity in a range of 90-500 mPa.s at 25 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a new formulation technology in the field of agrochemicals, especially in herbicides. More specifically, the present invention relates to an aqueous herbicidal suspension composition for simultaneous treatment with rice transplantation.

[0002]

2. Description of the Related Art In the field of agrochemicals, the types of preparations have conventionally been divided based on the dosage form of the preparation. Particularly in the field of herbicides for paddy rice, the application scene is weed control in paddy water. In view of the fact that the amount of the applied drug can be surely added and that the application can be performed in a labor-saving manner, granules in a granular form have occupied the mainstream. However, in the case of the granule form, in order to spread the water evenly as much as possible over the surface water and to reduce the work labor, in recent years, the technology to increase the size of the granule itself and the active ingredients (herbicidal activity) A reduction in the amount of application by increasing the content of the (component) has been measured.

[0003] On the other hand, in addition to solid preparations, herbicidal compositions in the form of liquid preparations and emulsions have heretofore been used, albeit slightly, for pretreatment of rice transplantation. Furthermore, recently,
Herbicides in the form of an aqueous suspension in liquid form have been used for post-planting treatment. Known techniques relating to this aqueous suspension of herbicide include, for example, a nonionic surfactant (1) having an HLB of 10 or less for the purpose of stabilizing an agrochemical active ingredient.
Aqueous Suspended Agrochemical Formulation (Japanese Patent Application Laid-Open No. 60-1101), comprising a certain specific compound and a viscosity adjusted to 250 to 30 centipoise. Method of using a suspended herbicide composition for pre-planting of flooded paddy fields (Japanese Patent Application Laid-Open No. 62-84002), specific physical properties (viscosity, initial water surface spreading speed and surface tension)
Water-suspended paddy field herbicide having a method and a method of applying it before rice transplantation (Japanese Patent Application Laid-Open No. 62-87501), in a finely divided aqueous suspension preparation, particularly for suppressing particle growth under high temperature conditions Aqueous suspension pesticide formulation (JP-A-5
No. 43401), a suspended herbicidal composition for paddy fields focusing on the prevention of the adhesion of the drug to the rice leaf blade, which is mainly caused by sprinkling and spraying, which is a feature of the aqueous suspension (Japanese Patent Application Laid-Open No. Hei 5-1056).
No. 01) and a water-applied herbicide (JP-A-5-201801) for the purpose of improving long-term storage stability and diffusibility in water.

As described above, many techniques relating to aqueous suspension preparations have been proposed, but the problem of adhesion to the leaf blade of rice seedlings caused by the liquid preparations inherently possessed by them has been proposed. However, there still remain problems to be solved, such as the problem of uneven distribution of the spray formulation, the problem of uneven distribution of herbicidal effects and the occurrence of phytotoxicity caused by insufficient diffusivity, and the problem of decomposition of active ingredients in the formulation. I have.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have conducted studies. As a result, the present inventors have solved the above-mentioned problems by using an aqueous suspended herbicidal composition described below. The inventors have found that the present invention can be performed, and have completed the present invention.

That is, according to the present invention, one or two kinds of hardly or insoluble water having a median particle diameter of 0.5 to 10 μm.
1 to 30% by weight of at least one herbicidally active compound, glycerin 5
10 to 10% by weight, and 50 to 85% by weight of water,
And an aqueous suspension of herbicide comprising a surfactant in an amount necessary to keep the herbicidally active compound in a suspended state, and having a viscosity at 25 ° C. in the range of 90 to 500 mPa · s. An agent composition is provided.

According to the present invention, the above-mentioned aqueous suspension herbicidal composition not only exerts a herbicidal effect accurately, but also contains glycerin as compared with conventional aqueous suspension preparations. Has been found to exhibit excellent properties in terms of storage stability.

In the present invention, the “medium particle size” is used as a scale indicating an “average particle” system of a particle group, and its value is a percentage of the total particles present in a certain particle size section. It is indicated by the value of the particle diameter when the cumulative distribution obtained by integrating the represented frequency distribution from the smaller or larger particle diameter shows 50%. The herbicidally active compounds used in the compositions according to the invention can have a median particle size in the range 0.5 to 10 μm, preferably 1 to 5 μm.

The herbicidally active compound used in the present invention is not particularly limited as long as it is generally used for paddy fields, but among them, those which are hardly soluble or insoluble in water are preferred. Here, “slightly soluble or insoluble in water” means
It means that the solubility in water at 25 ° C. is approximately 100 ppm or less. The following can be exemplified as typical examples of such herbicidally active compounds that are hardly soluble or insoluble in water.

2-benzothiazol-2-yloxy-
N-methylacetanilide, (RS) -2-bromo-N
-(Α, α-dimethylbenzyl) -3,3-dimethylbutyramide, 2-chloro-2 ′, 6′-diethyl-N-
(2-propoxydiethyl) acetanilide, 2-chloro-2 ', 6'-diethyl-N- (butoxydimethyl) acetanilide, 2-chloro-N- (3-methoxy-2-thenyl) -2', 6'- Dimethylacetanilide, S-
(4-chlorobenzyl) -N, N-diethylthiocarbamate, S-benzyl 1,2-dimethylpropyl (ethyl) thiocarbamate, O-3-tert-butylphenyl 6-methoxy-2-pyridyl (methyl) thiocarbamate , S-ethylhexahydro-1H-azepine-1
-Carbothioate, 1- (diethylcarbamoyl)-
3- (2,4,6-trimethylphenylsulfonyl)-
1,2,4-triazole, 1- (2-chlorophenyl) -4- (N-cyclopentyl-N-ethylcarbamoyl) -5 (4H) -tetrazolinone, 1- (2-chlorophenyl) -4- (N-cyclopentyl -N-propylcarbamoyl) -5 (4H) -tetrazolinone, 1-
(2-chlorophenyl) -4- (N-cyclohexyl-
N-ethylcarbamoyl) -5 (4H) -tetrazolinone (generic name fentrazamide), 1- (2-chloro-6
-Methylphenyl) -4- (N-cyclopentyl-N-
Propylcarbamoyl) -5 (4H) -tetrazolinone, 1- (2-bromophenyl) -4- (N-cyclopentyl-N-ethylcarbamoyl) -5 (4H) -tetrazolinone, 1- (2-bromophenyl) -4 − (N−
Cyclopentyl-N-propylcarbamoyl) -5 (4
H) -tetrazolinone, 1- (2-bromo-6-methylphenyl) -4- (N-cyclopentyl-N-propylcarbamoyl) -5 (4H) -tetrazolinone, methyl 2-[(4,6-dimethoxy-2) -Pyrimidinyl) oxy] -6- [1- (methoxyimino) ethyl] benzoate, methyl α- (4,6-dimethoxypyrimidin) -2-ylcarbamoylsulfamoyl-O-toluate (generic name bensulfuronmethyl), Ethyl 5-
(4,6-dimethoxypyrimidin-2-yl-carbamoylsulfamoyl) -1-methylpyrazole-4-carboxylate, N- (2-chloroimidazole [1,
2-a] pyridin-3-yl-sulfonyl) -N-
(4,6-dimethoxy-2-pyrimidyl) urea, N-
([4,6-dimethoxypyrimidin-2-yl] aminocarbonyl) -1-methyl-4- (2-methyl-2H-
Tetrazol-5-yl) -1H-pyrazole-5-sulfonamide, N-([4,6-dimethoxy-1,3,3
5-triazin-2-yl] aminocarbonyl) -2-
(2-methoxyethoxy) benzenesulfonamide, 1
-[[O- (cyclopropylcarbonyl) phenyl] sulfamoyl] -3- (4,6-dimethoxy-2-pyrimidinyl) urea, 4- (2,4-dichlorobenzoyl) -1,3-dimethylpyrazole-5 Yl-p-toluenesulfonate, 2- [4- (2,4-dichloro-
m-toluoyl) -1,3-dimethylpyrazole-5
Yloxy] -4-methylacetophenone, 2- [4-
(2,4-dichlorobenzoyl) -1,3-dimethylpyrazol] -5-yloxycoacetophenone, 2-
(Β-naphthyloxy) propionanilide, (RS)
-2- (2,4-dichloro-m-tolyloxy) propionanilide, n-butyl (R) -2- [4- (4-cyano-2-fluorophenoxy) phenoxy] propionate, 1- (α, α- Dimethylbenzyl) -3-p-
Tolylurea (generic name Daimulon), N-[(2-chlorophenyl) methyl] -N '-(1-methyl-1-phenylethyl) urea, 2-methyl-4-chlorophenoxybutyric acid, 2,4-dichlorophenoxyacetic acid , 2-ethylamino-4- (1,2-dimethylpropylamino) -6
-Methylthio-1,3,5-triazine, [3- (2-
Chloro-4-methylsulfonylbenzoyl) -4-phenylthio] bicyclo [3,2,1] oct-3-en-2-one and the like.

The composition of the present invention can contain the herbicidally active compounds as exemplified above alone or in combination of two or more. Particularly, those containing a tetrazolinone-based herbicidally active compound are preferable.

The content of the herbicidally active compound in the composition of the present invention can be in the range of 1 to 30% by weight, preferably 5 to 20% by weight. The content of glycerin used for ensuring the storage stability of the herbicidally active compound in the composition of the present invention can be in the range of 5 to 10% by weight. The stabilizing action of glycerin can exhibit a remarkable effect when the herbicidally active compound is a sulfonylurea compound in particular.

In the composition of the present invention, the surfactant used for keeping the herbicidally active compound in a suspended state is not particularly limited, and may be selected from a wide range according to the kind of the herbicidally active compound. For example, the following can be used as known representatives.

Lignin sulfonate, alkyl phosphate, fatty acid salt, alkyl sulfonate, alkyl benzene sulfonate, alkyl naphthalene sulfonate, naphthalene sulfonic acid formalin condensate, polyoxyalkylene alkyl ether sulfate, polyoxyalkylene Alkyl phenyl ether sulfate, polyoxyalkylene tristyryl phenyl ether sulfate, polyoxyethylene, polyoxypropylene block polymer sulfate, dialkyl sulfosuccinate, polyoxyalkylene alkyl ether sulfosuccinate salt, polyoxyalkylene alkyl phenyl ether phosphate Anionic surfactants such as salts; polyoxyalkylene alkyl phenyl ethers, polyoxyalkylene fatty acid esters, polyoxyl Quirentristyl phenyl ether, polyoxyalkylene alkylamine, sorbitan fatty acid ester, sucrose fatty acid ester, polyoxyalkylene sorbitan ester, glycerin fatty acid ester, polyoxyethylene-polyoxypropylene block polymer, polyoxyethylene-polyoxypropylene block polymer Nonionic surfactants such as alkyl phenyl ethers; amphoteric surfactants such as aliphatic alkyl betaines and alkyl ammonium salts; cationic surfactants such as alkyl pyridinium salts and polyethylene polyamine fatty acid amides.

As the surfactant used in the present invention, preferably, polyoxyalkylene alkylphenyl ether, polyoxyalkylene tristyryl phenyl ether, polyoxyalkylene alkyl phenyl ether sulfate, polyoxyalkylene tristyryl phenyl ether sulfate, Examples thereof include polyoxyalkylene tristyryl phenyl ether phosphate amine salt and dioctyl sulfosuccinate sodium salt.

The composition of the present invention may contain the above-mentioned surfactants alone or in combination of two or more. In the present invention, such a surfactant is
Used in an amount necessary to maintain the herbicidally active compound in an aqueous suspension, the amount of physical properties such as the particle size of the particles in the dispersion,
Although it depends on the type and properties of the surfactant, it can be easily determined by those skilled in the art by conducting small-scale experiments.

The composition of the present invention uses water as a dispersion medium, and the content of water can be in the range of 50 to 85% by weight.

The composition of the present invention has a viscosity at 25 ° C. of 90 to 500 mPa · s, preferably 120 to 300 mPa · s.
It is adjusted to be within the range of Pa · s. If the viscosity of the composition is less than 90 mPa · s, sedimentation of suspended particles increases during storage, and satisfactory properties cannot be maintained as a product in terms of stability. On the other hand, 500 mPa
If it exceeds s, it tends to drop during spraying, and the spread of the active ingredient in the surface water is insufficient due to a decrease in diffusivity, which is not preferable in terms of effect.

The adjustment of the viscosity in the composition of the present invention can be appropriately performed by, for example, adding a water-soluble polymer compound and / or an inorganic substance as exemplified below.

The composition of the present invention may optionally contain a water-soluble polymer compound for stabilizing the dispersion of the finely divided herbicidally active compound. Representative examples of water-soluble polymer compounds that can be used include, for example, gum arabic, sodium alginate, tragacanth gum, xanthan gum (xanthan gum), dextrin, gelatin, casein, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, polyvinyl alcohol, Examples thereof include polyvinylpyrrolidone and sodium polyacrylate.

In order to further stabilize the dispersion of the composition of the present invention, if necessary, white carbon,
Inorganic substances such as bentonite, talc, kaolin; pH of sodium hydrogen phosphate, potassium hydrogen citrate, etc.
It is also possible to add regulators.

The composition of the present invention may further contain, as other auxiliaries, an antifoaming agent (for example, silicone oil emulsion) for suppressing foaming during production and use, and a preservative (for example, Preventol D2). (Trade name) manufactured by Bayer: active ingredient benzyl alcohol mono (poly) hemiformal, Proxel GXL (trade name) manufactured by Zeneca:
The active ingredient 1,2-benzysothiazolin-3-one 20%, etc.), an antifreezing agent for preservation in cold regions (for example, ethylene glycol, propylene glycol, etc.), etc., substantially constitute the composition of the present invention. It can be arbitrarily compounded as long as it is not changed.

The method for producing the aqueous suspension herbicidal composition of the present invention is not particularly limited, but generally, a herbicidal active compound is added to a solution comprising water and a surfactant, mixed and mixed. Particles are dispersed and dispersed by a wet mill such as a ball mill and a sand mill. After the herbicidally active compound is ground to some extent, the mixture is mixed with a solution comprising a surfactant and water, and then wet-milled to form fine particles and dispersed; or In the case of a herbicidally active compound having a low melting point, the herbicidally active compound is heated and melted at 50 to 90 ° C., a surfactant is mixed with the compound, and water is added while stirring the mixed solution. The desired composition of the present invention can be obtained by a method such as micronization and dispersion by wet pulverization in the same manner as described above.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0025]

EXAMPLES The herbicidally active compounds in the compositions described in the examples are as follows: Fentrazamide: 1- (2-chlorophenyl) -4-
(N-cyclohexyl-N-ethylcarbamoyl) -5
(4H) -tetrazolinone bensulfuronmethyl (generic name) Daimulon (generic name) In the examples, "parts" are by weight unless otherwise specified.

Example 1 (Formulation Example 1) 1.63 parts of bensulfuron-methyl, 4.13 parts of fentrazamide, Newcargen FS-26 (combination product of polyoxyethylene tristyryl phenyl ether and sodium salt of dioctyl sulfosuccinate) 2 Department, SAG-
10 (trade name, manufactured by Nippon Unicar, component: 14% silicone oil emulsion) 0.5 part, glycerin 10
Parts, xanthan gum 2% aqueous solution 9 parts, bentonite 1
, 0.59 parts of a 10% aqueous solution of potassium dihydrogen phosphate and 71.15 parts of water were stirred and pulverized with a dyno mill to obtain a uniform aqueous suspension preparation. The crushing media has a diameter of 0.8
Hard non-alkali glass beads having a diameter of from 1.2 mm to 1.2 mm were used. This preparation has an average particle size of 2.1 μm and a viscosity of 2
20 mPa · s.

Example 2 (Formulation Example 2) 1.19 parts of bensulfuron-methyl, 4.13 parts of fentrazamide, 9.33 parts of Daimulon, Neucargen F
S-26 (polyoxyethylene tristyryl phenyl ether and dioctyl sulfosuccinate sodium salt) 3 parts, SAG-10 0.5 part, glycerin 1
0 part, xanthan gum 2% aqueous solution 6.5 part, bentonite 0.7 part, 0.6N hydrochloric acid aqueous solution 0.31 part and water 6
4.34 parts were stirred and pulverized with a dyno mill to obtain a uniform aqueous suspension preparation. The crushing media has a diameter of 0.8mm
And hard non-alkali glass beads having a diameter of 1.2 mm were used. The average particle size of the preparation is 1.9 μm and the viscosity is 200
mPa · s.

Examples of preparations obtained in the same manner as in Examples 1 and 2 are shown below. Formulation Example 3 Bensulfuron-methyl 1.63 parts Fentrazamide 4.13 parts Newcargen FS-26 2.00 parts SAG-10 0.50 parts Glycerin 10.00 parts (0.6N) aqueous hydrochloric acid 0.36 parts Bentonite 1. 00 parts Xanthan gum 2% aqueous solution 9.00 parts Water 71.38 parts

Formulation Example 4 Bensulfuron-methyl 1.19 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Glycerin 10.00 parts (0.6N) hydrochloric acid Aqueous solution 0.15 parts Bentonite 0.70 parts Xanthan gum 2% aqueous solution 7.50 parts Water 63.50 parts

Formulation Example 5 Bensulfuron methyl 1.19 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Glycerin 10.00 parts Potassium dihydrogen phosphate 10 % Aqueous solution 0.45 parts Bentonite 0.70 parts Xanthan gum 2% aqueous solution 7.50 parts Water 63.20 parts

Formulation Example 6 Bensulfuron-methyl 1.19 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Glycerin 10.00 parts Potassium dihydrogen phosphate 10 % Aqueous solution 0.65 parts Bentonite 0.70 parts Xanthan gum 2% aqueous solution 6.50 parts Water 64.00 parts

Comparative Example 1 Bensulfuron-methyl 1.63 parts Fentrazamide 4.13 parts Newcargen FS-26 2.00 parts SAG-10 0.50 parts Propylene glycol 10.00 parts 10% aqueous solution of potassium dihydrogen phosphate 1. 00 parts Bentonite 1.00 part Xanthan gum 2% aqueous solution 9.00 parts Water 70.74 parts

Comparative Example 2 Bensulfuron methyl 1.63 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Propylene glycol 10.00 parts (0.6N) Hydrochloric acid aqueous solution 0.31 part Bentonite 0.70 part Xanthan gum 2% aqueous solution 6.50 parts Water 63.90 parts

Comparative Example 3 Bensulfuron methyl 1.63 parts Fentrazamide 4.13 parts Newcargen FS-26 2.00 parts SAG-10 0.50 parts Propylene glycol 10.00 parts (0.6N) aqueous hydrochloric acid solution 0.38 Part Bentonite 1.00 part Xanthan gum 2% aqueous solution 9.00 parts Water 71.36 parts

Comparative Example 4 Bensulfuron methyl 1.19 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Propylene glycol 10.00 parts (0.6N) Hydrochloric acid aqueous solution 0.16 parts Bentonite 0.70 parts Xanthan gum 2% aqueous solution 7.50 parts Water 63.49 parts

Comparative Example 5 Bensulfuron-methyl 1.19 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Propylene glycol 10.00 parts Potassium dihydrogen phosphate 10% aqueous solution 0.60 part Bentonite 0.70 part Xanthan gum 2% aqueous solution 7.50 parts Water 63.05 parts

Comparative Example 6 Bensulfuron-methyl 1.19 parts Fentrazamide 4.13 parts Daimlon 9.33 parts Newcargen FS-26 3.00 parts SAG-10 0.50 parts Propylene glycol 10.00 parts Potassium dihydrogen phosphate 10% aqueous solution 0.86 part Bentonite 0.70 part Xanthan gum 2% aqueous solution 6.50 parts Water 63.79 parts

Test Example Stabilization Test with Glycerin Method The above preparations 1 to 6 and comparative examples 1 to 6 were stored at 40 ° C. for 3 months, and then the degradation rate of bensulfuron methyl in each preparation Was measured. As a measuring method, a high-performance liquid chromatographic method was used to quantify the herbicide active ingredient (bensulfuron-methyl). Table 1 shows the measurement results. In addition, as a comparison of the pharmaceutical composition of the present invention, Comparative Example 1 for Formulation Example 1, Comparative Example 2 for Formulation Example 2, and Formulation Example 3
For Comparative Example 3 and Comparative Example 4 for Formulation Example 4
However, Comparative Example 5 corresponds to Formulation Example 5, and Comparative Example 6 corresponds to Formulation Example 6.

[0039]

[Table 1]

[0040]

Industrial Applicability By adding glycerin, the storage stability of an active ingredient, particularly a sulfonylurea compound, in an aqueous suspension herbicidal composition can be increased.

Claims (5)

[Claims] 1. One or more herbicidally active compounds 1 having a median particle size of 0.5 to 10 μm, which are hardly soluble or insoluble in water.
-30% by weight, glycerin 5-10% by weight, and water 50
８５85% by weight and additionally contains the amount of surfactant required to keep the herbicidally active compound in suspension, and has a viscosity at 25 ° C. of 90-500 mPa · s.
Aqueous suspension herbicidal composition characterized by being within the range of: 2. The method according to claim 1, wherein the median particle size is 1 to 5 μm.
Aqueous suspension herbicidal composition according to Item 1. 3. The aqueous herbicidal suspension according to claim 1, which contains a tetrazolinone compound as the herbicidally active compound. 4. The surfactant is polyoxyalkylene alkyl phenyl ether, polyoxyalkylene tristyryl phenyl ether, polyoxyalkylene alkyl phenyl ether sulfate, polyoxyalkylene tristyryl phenyl ether sulfate, polyoxyalkylene tristyryl phenyl ether The aqueous herbicidal composition according to claim 1, which is one or more selected from the group consisting of amine phosphate salts and dioctyl sulfosuccinate sodium salt. 5. A viscosity at 25 ° C. of 120 to 300 m
The aqueous suspension herbicidal composition according to claim 1, which is in the range of Pa · s.