JP2002293702A - Aqueous suspension formulation for directly spraying on paddy field under flooding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous suspension formulation for direct spraying on a paddy field under flooding which is an aqueous suspension including a herbicidally active component, free from coagulation of the dispersoid even when frozen in storing, capable of easily dropping to the paddy field from a container without diluting with water and capable of carrying out a pretreatment for transplantation of a rice plant, a simultaneous treatment with transplantation of the rice plant or a treatment after the transplantation of the rice plant. SOLUTION: This aqueous suspension formulation for direct spraying on a paddy field under flooding comprises a herbicidally active component having solubility to water <=100 ppm at 20 deg.C and a modified polyvinyl alcohol and water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a pesticide preparation containing a herbicidal active ingredient, which is stored in a storage / spraying container without being diluted with water without dripping while dispersing during storage. The present invention relates to an improvement of an aqueous suspension formulation for direct spraying of flooded paddy fields, which can be sprayed, and can be treated before transplantation, simultaneous transplantation, and post-transplantation of rice.

[0002]

2. Description of the Related Art Heretofore, some aqueous suspension preparations in which a herbicidal active ingredient is suspended and dispersed in water are known. For example, the present invention relates to an aqueous suspension formulation in which a herbicide drug substance having a water solubility of 100 ppm (25 ° C.) or less is suspended and dispersed in water using a surfactant (Japanese Patent Publication No. 7-47521). Water is suspended in a poorly water-soluble herbicidal active ingredient and has a viscosity of 180-500 centipoise (20
° C), and the initial water surface spreading speed is 4.0 cm / sec (20
° C) or more, and the surface tension is 25.0 to 31.0 dyne / c.
The present invention relates to a herbicide for water-suspended paddy fields having physical properties of m (25 ° C.) (Japanese Patent Application Laid-Open No. 62-87501), having an average particle size of 0.5 to 5.0 μm and a water solubility of 100 ppm (2
A herbicidal active compound having a surface tension of 36 to 65 dyne / cm (25 ° C.) is suspended in water using a surfactant.
C)) (Japanese Patent Publication No. 7-47522), which comprises a herbicidally active compound, a surfactant and water and has a surface tension of 35 to 65 dyne /
Concerning an aqueous suspension formulation for herbicide having a physical property of 25 cm (25 ° C.) (JP-A-62-289502), comprising a hydrophobic herbicidal component (butamiphos) and polyvinyl alcohol or gum arabic, and a thickener and water. Oil-in-water suspension herbicidal composition (Japanese Patent Laid-Open No. 55-124)
No. 708), a paste-like or solid water-insoluble biocide having a melting point of 38 to 110 ° C., polyvinyl alcohol,
And an aqueous suspension biocidal composition comprising a water-insoluble thickener and water (JP-A-61-126001).

[0003]

The aqueous suspension formulation for direct spraying of a flooded paddy field using water as a dispersion medium can be dripped from the container as it is onto the paddy water without being diluted with water at the time of spraying the drug. It is an excellent dosage form in terms of economy, labor saving, etc. However, conventional aqueous suspension formulations for direct application to flooded sewage paddy fields are subject to natural environment, especially wind, Chemical damage occurred on the paddy rice in the part blown to the local part of the paddy field, and the herbicidal effect fluctuated. In addition, because the herbicidal active ingredient has not been sufficiently reached, the herbicidal effect is reduced in the central part of the paddy field even when sprayed from the ridge. Needed to be sprayed. In addition, since the formulation contains surfactants such as nonionic surfactants, anionic surfactants, and cationic surfactants, the drug easily adheres to the rice body when sprayed, causing problems such as causing phytotoxicity. Was easy to occur.

[0004] As an improvement over these problems, 2
An aqueous suspension formulation comprising a herbicidal active ingredient having a solubility in water at 0 ° C. of 100 ppm or less, a protective colloid agent and water (JP-A-10-316503);
There is an aqueous suspension formulation comprising a herbicidal active ingredient having a solubility in water at 100 ° C. of 100 ppm or less, a protective colloid agent, a high-boiling solvent and water (JP-A-11-158006). These techniques also have a problem that when the preparation freezes during long-term storage, the viscosity increases, or the dispersoids cause aggregation, and it becomes difficult to redisperse even when the temperature is returned to room temperature.

[0005] Therefore, an aqueous suspension preparation containing a herbicidal active ingredient, which does not cause agglomeration of the dispersoid even if it is frozen during storage. There is an expectation for an improvement in a preparation that can be easily added dropwise from a rice field and that can spread in rice fields.

[0006]

Means for Solving the Problems Accordingly, the present inventors have:
A study was made on the aqueous suspension formulation to improve the stability of the formulation during freeze reconstitution. As a result, an aqueous suspension formulation comprising a herbicidal active ingredient having a solubility in water at 20 ° C. of 100 ppm or less, a modified polyvinyl alcohol and water met this purpose and exhibited an excellent formulation stabilizing effect. As the modified polyvinyl alcohol, various modified polyvinyl alcohols such as a terminal alkyl group-modified polyvinyl alcohol, a side chain alkyl group-modified polyvinyl alcohol, a carboxyl group-modified polyvinyl alcohol, and an acetoacetyl group-modified polyvinyl alcohol are effective as described later. Was found. Among them, it has been found that particularly when the modified polyvinyl alcohol is a polyvinyl alcohol having an alkyl group at the terminal, a remarkable preparation stabilizing effect is exhibited. Further studies have found that the addition of a high-boiling solvent to these aqueous suspension preparations further improves the stability of the preparation during freeze-reconstitution, thereby completing the present invention.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The herbicidal active ingredient used in the present invention has a solubility in water at 20 ° C. of 100 ppm or less among those generally used as herbicides. In the present invention, one or more of these may be used in combination.

Examples of such herbicidally active ingredients include phenoxyacetic acid-based herbicides, diphenyl ether-based herbicides, carbamate-based herbicides, acid amide-based herbicides, urea-based herbicides, sulfonylurea-based herbicides, and pyrimidyloxybenzoic acid. Herbicides, triazine herbicides, diazinon herbicides, diazole herbicides, dinitroaniline herbicides, aromatic carboxylic acid herbicides, fatty acid herbicides,
And organic phosphorus-based herbicides. Specific specific herbicidal active ingredients contained therein are described, for example, in "Agrochemical Handbook 2001 Edition" (Japan Plant Protection Association)
Issued on November 1, 2001), "SHIBUYA IN
"DEX 8th Edition" (issued December 15, 1998), "The Pesticide Man"
ual Eventh Edition "(Bri
tissue Crop Protection Coun
cil issuance). However, the herbicidal active ingredients that can be used in the present invention are not limited to those described in the above-mentioned various strains and in the above-mentioned documents, and the herbicidal active ingredients used within the scope of the present invention. Any ingredient can be used.

The content of these herbicidally active ingredients in the preparation can be arbitrarily changed depending on the kind of the herbicidal active ingredient, but may be added in the range of 0.1 to 60% by weight in the preparation.

The modified polyvinyl alcohol that can be used in the present invention is obtained by polymerizing a vinyl ester using an aldehyde or a mercaptan having an alkyl group having 6 or more carbon atoms as a chain transfer agent, and saponifying the obtained polyvinyl ester polymer. The obtained terminal alkyl group-modified polyvinyl alcohol, a side chain alkyl group-modified polyvinyl alcohol obtained by copolymerizing a vinyl ester and an olefin containing an alkyl group, and saponifying the obtained polyvinyl ester-based polymer, acrylic acid, methacrylic acid Carboxyl group-modified polyvinyl alcohol having a carboxyl group introduced by a carboxylic acid such as an acid or itaconic acid, cation-modified polyvinyl alcohol having a cationic monomer introduced into a molecule thereof, and silicon-containing group-modified polymer having a silicon-containing group introduced therein. Vinyl alcohol, ethylene sulfonic acid-modified polyvinyl alcohol, acetoacetyl group-modified polyvinyl alcohol obtained by reacting polyvinyl alcohol with diketene, and the like. These modified polyvinyl alcohols can also be introduced into esterified or acetalized hydroxyl groups in polyvinyl alcohol, by copolymerization with other monomers, or by etherification, esterification, or acetalization of copolymers. Method, but
It is not limited to this. There is no problem even if one or more of these are used in combination.

[0011] Such a modified polyvinyl alcohol is
Those synthesized by a conventional method can be used. Also, commercially available modified polyvinyl alcohol can be used. The following can be mentioned as such commercially available modified polyvinyl alcohol. As the terminal alkyl group-modified polyvinyl alcohol, for example, Kuraray Povar MP-203 (trade name, manufactured by Kuraray Co., Ltd., average degree of polymerization 300, saponification degree 86.5 to 89.5 mol%), Kuraray Povar MP-103 (stock) Kuraray brand name, average polymerization degree 300, saponification degree 98.0-9
9.0 mol%), and examples of the side chain alkyl group-modified polyvinyl alcohol include Shin-Etsu Poval COTP-20
00 (trade name, manufactured by Shin-Etsu Chemical Co., Ltd., saponification degree 86)
-90 mol%), as the carboxyl group-modified polyvinyl alcohol, for example, Kuraray Povar PVA KL
-506 (Kuraray Co., Ltd., average polymerization degree 60
0, a saponification degree of 74.0 to 80.0 mol%) and examples of the cation-modified polyvinyl alcohol include Kuraray Povar PVA C-506 (trade name, manufactured by Kuraray Co., Ltd., average degree of polymerization 600, saponification degree 74.0 to 74.0). Examples of the silicon-containing modified polyvinyl alcohol include Kuraray Povar R-2105 (trade name, manufactured by Kuraray Co., Ltd., average polymerization degree 500, saponification degree 98.
0-99.0 mol%), and as the sulfonic acid group-modified polyvinyl alcohol, for example, Gohselan L-0301
(Trade name of Nippon Synthetic Chemical Industry Co., Ltd.), as acetoacetyl group-modified polyvinyl alcohol, for example,
GOHSEFIMER Z-200 (trade name, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., degree of saponification of 99.0 mol% or more) and the like.

Among these modified polyvinyl alcohols, particularly preferred is a polyvinyl alcohol modified with a terminal alkyl group.

The content of the modified polyvinyl alcohol in the preparation is 0.1 to 20% by weight. If the content is small, the stabilizing effect of the preparation is low, and if it is less than 0.1%, the practicality is low. Further, even if added in an amount of 20% or more, improvement of the stabilizing effect cannot be expected very much. Therefore, the content of the modified polyvinyl alcohol is preferably 0.5 to 15% by weight in view of both the effect and the economic efficiency.

The high-boiling solvents that can be used in the present invention include:
For example, Solvesso 150 (trade name manufactured by Exxon Corporation), Hisol E, Hisol F (trade name manufactured by Nippon Petrochemical Co., Ltd.), Cactus Solvent P100, Cactus Solvent P150, Cactus Solvent P18
7, Cactus Solvent P200 (trade name, manufactured by Japan Energy Co., Ltd.), Alken 56N, Alken 60N
H, alkene L (trade name, manufactured by Nippon Petrochemical Co., Ltd.), alkylbenzene solvents such as Cactus Solvent 22
0, Cactus Solvent P240 (trade name manufactured by Japan Energy Co., Ltd.), Solvesso 200 (trade name manufactured by Exxon Chemical Co., Ltd.), purified methylnaphthalene (manufactured by Sumitomo Chemical Co., Ltd.), alkyl naphthalene-based solvents such as diisopropyl naphthalene, isoparaffin , Liquid paraffins, paraffinic solvents such as n-paraffin, naphthesols (manufactured by Nippon Petrochemical Co., Ltd.), naphthenic solvents such as exol (product name manufactured by Exxon Chemical Co., Ltd.), propylene glycol monomethyl ether, dipropylene glycol monomethyl ether , Ether solvents such as diethylene glycol mono-n-butyl ether, alcohols such as 3-methyl-3-methoxybutanol, 3-methyl-3-methoxybutyl acetate, 3-methyl-1,3-butanediol Alkylpyrrolidone solvents such as N-methylpyrrolidone, n-octylpyrrolidone, n-dodecylpyrrolidone, Dupont DBE (trade name of Dupont Co., Ltd.), ditridecyl phthalate,
Polybases such as diisobutyl adipate, diisodecyl adipate, didecyl phthalate, dialkyl phthalate, trinormal alkyl trimellitate, tri-2-ethylhexyl trimellitate, trialkyl trimellitate, triisodecyl trimellitate, and dioleyl adipate Acid ester solvents, isobutyl oleate, coconut fatty acid methyl, methyl laurate, palm fatty acid methyl, isopropyl palmitate, isotridecyl stearate, 2-ethylhexyl stearate, methyl oleate, isobutyl oleate, octyl oleate, oleic acid Fatty acid esters such as lauryl and decyl oleate, aromatic hydrocarbon solvents having a basic skeleton of diallylethane such as 1-phenyl-1-xylylethane or triallyldiethane [C Orres SAS-296, Hisol SAS-LH (Nippon Petrochemicals product name Co., Ltd.)]
Vegetable oil fatty acid esters such as rice bran oil fatty acid methyl ester, soybean oil fatty acid methyl ester, rapeseed oil, etc.
Vegetable oils such as soybean oil, castor oil, cottonseed oil, corn oil and the like can be mentioned. However, the present invention is not limited to only these examples, and there is no problem even if one or more of these are used in combination.

The content of the high boiling solvent in the preparation is 1 to 60% by weight, preferably 5 to 50% by weight.

If necessary, auxiliaries such as thickeners, defoamers, antifreeze agents, antiseptic and fungicides, stabilizers for herbicidally active ingredients, and the like can be used as necessary.

As the thickener, those generally used may be used, for example, xanthan gum, tragacanth gum, casein, dextrin, colloidal hydrous aluminum silicate, colloidal hydrous magnesium silicate, colloidal hydrous aluminum magnesium silicate , Carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), and the like, but are not limited thereto, and there is no problem even if one or more of these are used in combination.

Further, as the defoaming agent, silicon-based or fatty acid-based substances can be used. In addition, ethylene glycol, propylene glycol, glycerin and the like can be used as the antifreezing agent. As the antiseptic / antifungal agent, potassium sorbate, p-chloro-
Meta-xylenol, butyl p-oxybenzoate, and the like can be used. Further, as a stabilizer of the herbicidal active ingredient, an antioxidant, an ultraviolet ray inhibitor, a crystal precipitation inhibitor and the like may be added. However, the present invention is not limited to the auxiliaries exemplified herein, and various auxiliaries can be used as long as the object of the present invention can be achieved.

The aqueous suspension preparation of the present invention can be used irrespective of the water depth, provided that the paddy field after flooding is flooded. In other words, from the condition where a slight water layer exists on the soil surface such as when planting rice, the water depth of 3
Until the soil surface is not completely dried, it can be sprayed up to a state where water of up to 5 cm is covered. In addition, it can be used by dropping it into the water mouth when irrigation water is supplied. In addition, it may be under conditions of low water at the time of rice planting, such as dropping treatment at the same time as rice planting, and if it is treated, the herbicidal active ingredient will diffuse to some extent, become more uniform by subsequent water entry, and exhibit a sufficient herbicidal effect. Can be.

In addition, it can be sprayed before, during, or after transplanting the rice. In addition, it can be applied to directly flooded paddy fields.

The aqueous suspension of the present invention can be sprayed by using the stock solution without diluting it with more water, or by using a small amount of water to make a 2 to 5-fold high-concentration diluent and dropping it into a paddy field. It is not necessary to apply the ink uniformly over the entire paddy field as in the case of granules. Spraying may be carried out by shaking hands in a stock solution or a high-concentration diluent, for example, a plastic container having a capacity of 500 ml, or by spraying or spraying using a pressurized sprayer. Furthermore, airborne spraying or dripping from a RC (radio control) helicopter, which has been widely used in recent years, is also possible. Further, the inflow water may be subjected to a dropping treatment at the water inlet (water mouth) of the paddy field, and may be poured into the paddy field together with the inflow water.

The application rate per unit area of the aqueous suspension preparation of the present invention is not particularly limited. However, from the viewpoint of labor and economic efficiency of spraying, in the case of spraying undiluted solution, 0.0% per 10 ares.
It ranges from 5 liters to 2 liters, preferably from 0.1 liters to 1.5 liters. In the case of spraying with a high concentration diluent (2 to 5 times), 1
0.1 to 6 liters per 0 ares, preferably 0.2 to 5 liters.

[0023]

EXAMPLES Next, examples of the aqueous suspension formulation for direct application to flooded sewage paddy fields according to the present invention will be described, but the present invention is not limited thereto.

In the examples, all parts are by weight.

Example 1 In 80.8 parts of water, 8 parts of polyvinyl alcohol modified with a terminal alkyl group (trade name “Kuraray Povar MP-203”, manufactured by Kuraray Co., Ltd.) was dissolved, and MCPA thioethyl stock was used.
2 parts and 3 parts of propylene glycol
DL type [Willie A Bacco Fair AG (W
trade name manufactured by illily A Bachofer AG)
The same shall apply hereinafter), and the pulverized liquid was finely pulverized so as to have an average particle diameter of 2 μm. At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C.

The media for grinding has a diameter of 0.1 mm.
Hard glass beads of 7 to 1.2 mm were used. 4 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid, and the mixture was uniformly mixed using a three-one motor (trade name, manufactured by HEIDON) to obtain an aqueous suspension formulation.

The crushing medium has a diameter of 0.7.
The use of hard glass beads of ~ 1.2 mm, the addition of a 2% aqueous solution of xanthan gum of this pulverized liquid, and the uniform mixing using a three-one motor to form an aqueous suspension formulation
The same applies to the following examples unless otherwise specified.

Example 2 In place of polyvinyl alcohol modified with a terminal alkyl group in Example 1, 3 parts of a side chain alkyl group-modified polyvinyl alcohol (trade name “Shin-Etsu Poval COT P-2000” manufactured by Shin-Etsu Chemical Co., Ltd.) was used. An aqueous suspension was prepared in the same manner as in Example 1 except that the amount of water was changed to 85.8 parts.

Example 3 10 parts of a carboxyl group-modified polyvinyl alcohol (trade name "Kuraray Poval KL-506" manufactured by Kuraray Co., Ltd.) was dissolved in 62.5 parts of water.
Parts, 0.5 parts of hydrous aluminum silicate (trade name "Kunipia F" manufactured by Kunimine Chemical Industry Co., Ltd.) and 3 parts of propylene glycol, and using a Dynomill KDL type, finely pulverize the solution so that the average particle diameter becomes 3 μm. Crushed. And
An aqueous suspension was obtained in the same manner as in Example 1 except that 3 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Example 4 Instead of the carboxy group-modified polyvinyl alcohol of Example 3, 5 parts of cation-modified polyvinyl alcohol (trade name "Kuraray Povar C-506" manufactured by Kuraray Co., Ltd.) was used, and water was reduced to 67.5 parts. Except as described above, it was prepared according to Example 3 to obtain an aqueous suspension preparation.

Example 5 In 75.5 parts of water, 3 parts of a silicon-containing group-modified polyvinyl alcohol (trade name "Kuraray Povar R-2105" manufactured by Kuraray Co., Ltd.) was dissolved, and 12 parts of an oxadiazone base material, hydrous magnesium silicate [ “Panger FF” (trade name, manufactured by TOLSA)] 0.5 part and propylene glycol 3 parts were added, and the mixture was finely pulverized using a Dynomill KDL type so as to have an average particle diameter of 3 μm. Example 1 was repeated except that 6 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.
An aqueous suspension was obtained in the same manner as described above.

Example 6 In 59 parts of water, 5 parts of a sulfonic acid group-modified polyvinyl alcohol (trade name: "Goselan L-0301" manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was dissolved, and a jet-omizer (Jet-O-mizer) was previously prepared. (Trade name, manufactured by Seishin Enterprise Co., Ltd.), 27 parts of CNP raw material pulverized to an average particle diameter of 4 μm, 3 parts of propylene glycol and 2 parts
6 parts of an aqueous xanthan gum solution were added and mixed using a three-one motor, and then 6000 rpm using a TK auto homomixer (trade name of Nippon Tokushu Kika Kogyo Co., Ltd.).
For 30 minutes to obtain a homogeneous aqueous suspension formulation.

Example 7 In place of the sulfonic acid group-modified polyvinyl alcohol of Example 6, acetoacetyl group-modified polyvinyl alcohol (trade name “Gosefimer Z” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was used, and water was used. An aqueous suspension was prepared by following the procedure of Example 6 while changing the amount to 60 parts.

Example 8 In 71.8 parts of water, 8 parts of polyvinyl alcohol modified with a terminal alkyl group (trade name "Kuraray Povar MP-203" manufactured by Kuraray Co., Ltd.) was dissolved, and isobutyl oleate (trade name "Vinisizer 30") was previously dissolved. Kao Corporation) 1
0 parts and a solution prepared by dissolving 4.2 parts of the MCPA thioethyl stock and 3 parts of propylene glycol were added.
The pulverized liquid was finely pulverized using a DL mold so that the average particle diameter of the pulverized liquid was 2 μm. At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C. Then, an aqueous suspension was obtained in the same manner as in Example 1 except that 3 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Example 9 Example 8 was repeated except that isobutyl oleate was replaced with 10 parts of methylnaphthalene (trade name: “Solvesso 200” manufactured by Exxon Chemical Co., Ltd.) in the preparation composition of Example 8.
To prepare an aqueous suspension.

Example 10 In 66.3 parts of water, 8 parts of polyvinyl alcohol modified with an alkyl group at the terminal (trade name "Kuraray Povar MP-103" manufactured by Kuraray Co., Ltd.) was dissolved, and isoparaffin (trade name "Isolzol 300" Nippon Oil) was dissolved in advance. After 16 parts of Chemical Co., Ltd. and 4.2 parts of MCPA thioethyl raw material are dissolved, hydrous aluminum silicate (trade name “Kunipia F”)
(Kunimine Chemical Industry Co., Ltd.) (0.5 parts) and propylene glycol (3 parts) were added, and the mixture was finely pulverized using a Dynomill KDL type to an average particle diameter of 2 μm. At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C. Then, an aqueous suspension was obtained in the same manner as in Example 1 except that 2 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Example 11 Five parts of polyvinyl alcohol modified with a side chain alkyl group (trade name “Shin-Etsu Poval COT P-2000” manufactured by Shin-Etsu Chemical Co., Ltd.) was dissolved in 65.8 parts of water, and isobutyl adipate (trade name) was dissolved in advance. 20 parts of "Vinicizer 40" (manufactured by Kao Corporation), 4.2 parts of MCPA thioethyl base material and 3 parts of propylene glycol were added, and the mixture was finely pulverized using a Dynomill KDL type to an average particle diameter of 2 μm. . At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C. Then, an aqueous suspension was obtained in the same manner as in Example 1 except that 2 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Example 12 In 52 parts of water, 10 parts of a carboxyl group-modified polyvinyl alcohol (trade name "Kuraray Poval KL-506" manufactured by Kuraray Co., Ltd.) was dissolved, and 21 parts of a biphenox raw material were dissolved.
13 parts of naphthene (“Naphthesol M” manufactured by Nippon Petrochemical Co., Ltd.) and 3 parts of propylene glycol were added, and the mixture was finely pulverized using a Dynomill KDL type so as to have an average particle diameter of 4 μm. Then, an aqueous suspension was obtained in the same manner as in Example 1 except that 1 part of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Example 13 5 parts of a cationically modified polyvinyl alcohol (trade name “Kuraray Povar C-506” manufactured by Kuraray Co., Ltd.) in the preparation composition of Example 12 in which the modified polyvinyl alcohol and the high boiling point solvent are shown in Table 1, and alkylbenzene (Trade name "Solvesso 150" manufactured by Exxon Chemical Co., Ltd.) was prepared in the same manner as in Example 12 except that the amount was 10 parts and the amount of water was 60 parts, to obtain an aqueous suspension preparation.

Example 14 In 59.5 parts of water, 4 parts of a silicon-containing group-modified polyvinyl alcohol (trade name "Kuraray Povar R-2105" manufactured by Kuraray Co., Ltd.) was dissolved, and 12 parts of an oxadiazone base material and diisopropylnaphthalene (trade name) 20 parts of “KMC-113” manufactured by Kureha Chemical Industry Co., Ltd.), 0.5 parts of hydrous magnesium silicate [trade name “Panger”, manufactured by TOLSA) and 3 parts of propylene glycol were added, and Dynomill KDL type was added. And pulverized so that the average particle diameter becomes 3 μm. Then, an aqueous suspension was obtained in the same manner as in Example 1 except that 1 part of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Example 15 In 56 parts of water, 5 parts of a sulfonic acid group-modified polyvinyl alcohol (trade name “Gosenal L-0301” manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was dissolved, and the mixture was previously dissolved in a Jet-O-mizer. And 27 parts of a CNP raw material finely ground to an average particle size of 4 μm using castor oil 5
, 3 parts of propylene glycol and 4 parts of a 2% xanthan gum aqueous solution were added and mixed using a three-one motor, followed by stirring at 4,000 rpm for 30 minutes using a TK auto-homomixer to obtain a uniform aqueous suspension preparation.

Example 16 In the preparation composition of Example 15, the modified polyvinyl alcohol and the high boiling point solvent were acetoacetyl group-modified polyvinyl alcohol (trade name “Gosefimer Z-2”) shown in Table 1.
00 "manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) 4 parts, dibasic acid ester (trade name" Dupont DBE "manufactured by Dupont Co., Ltd.) 10 parts, and prepared according to Example 15 except that water was 52 parts. An aqueous suspension was obtained.

Comparative Example 1 An average polymerization degree of 300 and a saponification degree of 86.5 to 80.8 parts of water.
89.5 mol% of polyvinyl alcohol (trade name “Kuraray Poval PVA-203” manufactured by Kuraray Co., Ltd.) (8 parts) is dissolved, MCPA thioethyl base (4.2 parts) and propylene glycol (3 parts) are added, and Dynomill KDL type is used. The pulverized liquid was finely pulverized so as to have an average particle diameter of 2 μm. At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C. Hard glass beads having a diameter of 0.7 to 1.2 mm were used as the grinding media. 4 parts of a 2% xanthan gum aqueous solution was added to the pulverized liquid, and the mixture was uniformly mixed using a three-one motor to obtain an aqueous suspension.

Comparative Example 2 Polyoxyethylene tristyryl phenyl ether (trade name "SOPROPHOR B") was used as a surfactant instead of the polyvinyl alcohol of Comparative Example 1.
SU (Rhone Poulin) 3 parts, water was 85.
An aqueous suspension was prepared in the same manner as in Comparative Example 1 except that the amount was changed to 8 parts.

Comparative Example 3 An average degree of polymerization of 500 and a degree of saponification of 72.5 to 74.5 were used instead of the carboxyl group-modified polyvinyl alcohol of Example 3.
Using 8 parts by mol of polyvinyl alcohol (trade name “Kuraray Povar PVA-505” manufactured by Kuraray Co., Ltd.),
Prepared according to Example 3 except that water was 64.5 parts,
An aqueous suspension was obtained.

Comparative Example 4 In place of the polyvinyl alcohol of Comparative Example 3, 2 parts of polyoxyethylene octyl phenyl ether (trade name “SOLPOL OP-10” manufactured by Toho Chemical Industry Co., Ltd.) was used as a surfactant, and water was added at 70%. Aqueous suspension was prepared in the same manner as in Comparative Example 3 except that the amount was 0.5 part.

Comparative Example 5 In place of the silicon-containing group-modified polyvinyl alcohol of Example 5, the average degree of polymerization was 1300, and the degree of saponification was 92.5 to 94.
An aqueous suspension was obtained by preparing according to Example 5, except that 3 parts of 5 mol% of polyvinyl alcohol (trade name "Kuraray Povar PVA-613" manufactured by Kuraray Co., Ltd.) was used.

Comparative Example 6 Polyoxyethylene tristyryl phenyl ether (trade name “SOPROPHOR”) was used as a surfactant instead of the polyvinyl alcohol of Comparative Example 5.
S / 25 "(Rhone Poulin Co.) except that 3 parts were used to prepare an aqueous suspension.

Comparative Example 7 Instead of the sulfonic acid group-modified polyvinyl alcohol of Example 6, the average degree of polymerization was 1700, and the degree of saponification was 82.0 to 84.
A uniform aqueous suspending agent was prepared by the same composition and operation as in Example 6 except that 6 parts of 0 mol% polyvinyl alcohol (trade name "Kuraray Povar PVA-317" manufactured by Kuraray Co., Ltd.) was used and water was 58 parts. I got

Comparative Example 8 Instead of the polyvinyl alcohol of Comparative Example 7, an alkylphenol ethylene oxide / propylene oxide block copolymer (trade name “SOPROPHOR 497 / P”, Rhone
Aqueous suspension was obtained in the same manner as in Comparative Example 7, except that 4 parts of Poulin Co.) was used and water was changed to 60 parts.

Comparative Example 9 The average polymerization degree was 500 and the saponification degree was 80.0-83.
A uniform aqueous suspension was obtained by the same composition and operation as in Example 8, except that 8 parts of 0 mol% of polyvinyl alcohol (trade name "Kuraray Povar PVA-405" manufactured by Kuraray Co., Ltd.) was used.

Comparative Example 10 Lignin sulfonic acid sodium salt (trade name "SOLPOL 9047K" manufactured by Toho Chemical Industry Co., Ltd.) was dissolved in 73.8 parts of water as a surfactant, and isobutyl oleate (trade name "Vinisizer") was dissolved in advance. 30 "manufactured by Kao Corporation, 10 parts, MCPA thioethyl bulk 4.2 parts, polyoxyethylene caster oil (trade name" SOLPOL C ")
A30 "manufactured by Toho Chemical Industry Co., Ltd.)
The pulverized liquid was finely pulverized using a DL type so that the average particle diameter of the pulverized liquid was 2 μm. At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C. Then, an aqueous suspension was obtained in the same manner as in Comparative Example 1 except that 5 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Comparative Example 11 The procedure of Comparative Example 9 was repeated except that 10 parts of methylnaphthalene (trade name “Solvesso 200” manufactured by Exxon Chemical Co., Ltd.) was used instead of isobutyl oleate of Comparative Example 9.
A homogeneous aqueous suspension was obtained.

Comparative Example 12 A uniform aqueous solution was prepared in the same manner as in Comparative Example 10 except that 10 parts of methylnaphthalene (trade name “Solvesso 200” manufactured by Exxon Chemical Co., Ltd.) was used instead of isobutyl oleate of Comparative Example 10. A suspension was obtained.

Comparative Example 13 The average polymerization degree was 500 and the saponification degree was 80.0 to 8 in place of the polyvinyl alcohol modified with a terminal alkyl group in Example 10.
A uniform aqueous suspension was obtained by the same composition and operation as in Example 10 except that 8 parts of 3.0 mol% of polyvinyl alcohol (trade name "Kuraray Povar PVA-405" manufactured by Kuraray Co., Ltd.) was used.

Comparative Example 14 2 parts of ligninsulfonic acid sodium salt (trade name "SOLPOL 9047K" manufactured by Toho Chemical Industry Co., Ltd.) was dissolved as a surfactant in 67.3 parts of water, and isoparaffin (trade name "ISOSOL 300") was dissolved in advance. A liquid in which 16 parts of Nippon Petrochemical Co., Ltd., 4.2 parts of MCPA thioethyl bulk material, and 2 parts of polyoxyethylene caster oil (trade name "SOLPOL CA30" manufactured by Toho Chemical Industry Co., Ltd.) are mixed, and hydrous silicic acid. Aluminum (Product name "Kunipia F"
(Kunimine Chemical Industry Co., Ltd.) (0.5 parts) and propylene glycol (3 parts) were added, and the mixture was finely pulverized using a Dynomill KDL type so that the average particle diameter of the pulverized liquid was 3 μm. At this time, the pulverization was performed while cooling so that the temperature of the pulverization liquid did not exceed 20 ° C. Then, an aqueous suspension was obtained in the same manner as in Comparative Example 1 except that 5 parts of a 2% aqueous xanthan gum solution was added to the pulverized liquid.

Comparative Example 15 The average degree of polymerization was 300 and the degree of saponification was 86.5 to 8 instead of the side chain alkyl group-modified polyvinyl alcohol of Example 11.
The same composition and operation as in Example 11 were carried out, except that 8 parts of 9.5 mol% of polyvinyl alcohol (trade name "Kuraray Povar PVA-203" manufactured by Kuraray Co., Ltd.) was used and water was changed to 62.8 parts. An aqueous suspension was obtained.

Comparative Example 16 The procedure of Comparative Example 12 was repeated, except that 20 parts of diisobutyl adipate (trade name “Vinicizer 40” manufactured by Kao Corporation) was used instead of methylnaphthalene of Comparative Example 12, and water was changed to 63.8 parts. Prepared in a similar manner to obtain a homogeneous aqueous suspension.

Comparative Example 17 The average degree of polymerization was 500 and the degree of saponification was 72.5 to 7 in place of the carboxyl group-modified polyvinyl alcohol of Example 12.
A uniform aqueous suspension was obtained by the same composition and operation as in Example 12 except that 10 parts of 4.5 mol% of polyvinyl alcohol (trade name "Kuraray Povar PVA-505" manufactured by Kuraray Co., Ltd.) was used.

Comparative Example 18 Polyvinylethylene octyl phenyl ether (trade name "SOLPOL OP-14" manufactured by Toho Chemical Industry Co., Ltd.) was used in place of the polyvinyl alcohol of Comparative Example 17, and the water content was changed to 58 parts. Is the same composition as Comparative Example 17,
By operation, a uniform aqueous suspension was obtained.

Comparative Example 19 Alkylbenzene (trade name “Solvesso 150” manufactured by Exxon Chemical Co., Ltd.) was used instead of naphthene in Comparative Example 17.
A uniform aqueous suspension was obtained by the same composition and operation as in Comparative Example 17 except that 0 part was used and water was 55 parts.

Comparative Example 20 Alkylbenzene (trade name “Solvesso 150” manufactured by Exxon Chemical Co., Ltd.) was used instead of naphthene in Comparative Example 18.
A uniform aqueous suspension was obtained by the same composition and operation as in Comparative Example 18 except that 0 part was used and water was changed to 61 parts.

Comparative Example 21 An average degree of polymerization of 1300 and a degree of saponification of 92.5 to 9 were used in place of the silicon-containing group-modified polyvinyl alcohol of Example 14.
A uniform aqueous suspension was obtained by the same composition and operation as in Example 14 except that 4 parts of 4.5 mol% of polyvinyl alcohol (trade name "Kuraray Povar PVA-613" manufactured by Kuraray Co., Ltd.) was used.

Comparative Example 22 A polyoxyethylene polyoxypropylene block polymer (trade name “Pluronic P-85” manufactured by Asahi Denka Kogyo KK) in place of the polyvinyl alcohol of Comparative Example 21
A uniform aqueous suspension was obtained by the same composition and operation as in Comparative Example 21 except that 4 parts were used.

Comparative Example 23 The average degree of polymerization was 1700 and the degree of saponification was 82.0 to 8 in place of the sulfonic acid group-modified polyvinyl alcohol of Example 15.
6 parts of 4.0 mol% polyvinyl alcohol (trade name "Kuraray Povar PVA-317" manufactured by Kuraray Co., Ltd.) was used, and the same composition and operation as in Example 15 were carried out, except that water was 55 parts. A clouding agent was obtained.

Comparative Example 24 Instead of the polyvinyl alcohol of Comparative Example 23, 5 parts of polyoxyethylene styryl phenyl ether (trade name “SOLPOL T-20” manufactured by Toho Chemical Industry Co., Ltd.) was used.
A uniform aqueous suspension was obtained by the same composition and operation as in Comparative Example 23 except that the amount of water was changed to 56 parts.

Comparative Example 25 The same as Comparative Example 23 except that 10 parts of a dibasic acid ester (trade name “Dupont DBE” manufactured by DuPont) was used instead of castor oil of Comparative Example 23, and water was changed to 50 parts. A homogeneous aqueous suspension was obtained by the composition and operation.

Comparative Example 26 Polyvinylethylene octyl phenyl ether (trade name “SOLPOL OP-10” manufactured by Toho Chemical Industry Co., Ltd.) was used in place of the polyvinyl alcohol of Comparative Example 25, and 3 parts of water were used, except that the water content was changed to 53 parts. A uniform aqueous suspension was obtained by the same composition and operation as in Comparative Example 25.

[0069]

[Effects of the Invention] By implementing the aqueous suspension for direct spraying of flooded sewage paddy fields of the present invention, the following effects can be obtained. First, the formulation has good stability over a long period of time, and does not cause problems such as aggregation of dispersoids even when the formulation freezes during storage. Secondly, the herbicidal active ingredient in the rice paddy water has good diffusibility and reachability, spreads uniformly and quickly over a wide range, and has a stable herbicidal effect without blowing by wind. Thirdly, since the preparation is a dispersion using water as a dispersion medium, there is little danger such as ignitability and flammability, and there is no problem of environmental irritation due to irritation to human body and odor. Fourth, from the time of rice padding, before rice transplantation, simultaneous transplantation,
It can be sprayed after transplanting, especially at the time of flooding after rice transplantation, and can be sprayed at any time if it is flooded. It is only necessary to drop the solution and pour it together with the inflowing water, and labor for spraying the medicine can be saved.

Next, the usefulness of the aqueous suspension preparation of the present invention is shown by test examples.

Test Example 1 A 500 ml glass bottle was charged with 400 ml of the aqueous suspension obtained according to the examples and comparative examples, and sealed, and then subjected to a temporal abuse test under the following two conditions. Condition 1: 40 ° C. for 90 days Condition 2: After storing at 40 ° C. for 7 days, holding at −10 ° C. for 7 days was defined as one cycle, and this was repeated 7 times (total of 98 days). Then, the suspension stability, the change in viscosity, the presence or absence of crystal precipitation, and the presence or absence of gelation of the aqueous suspensions tested under the conditions 1 and 2 were observed. The suspension stability of the suspension layer in the container was settled to the lower layer, and the height (cm) of the water layer (upper layer) formed in the upper layer and the whole layer was measured, and calculated by the following formula.

[0072]

(Equation 1)

The results are shown in Table 1 for Examples and Table 2 for Comparative Examples.

Test Example 2 Diffusivity test A test section (flooding depth: 5 cm) having an area of 9 square meters (3 m × 3 m) was made in one section, and a sample prepared according to the example was placed at the center (point A) from the water surface. Sprayed directly with a pipette from a height of 1 m. 1 hour after treatment, center of test plot (point A)
And 5cm depth at each of four corners (points BE to E)
Water from the water surface to the water surface was collected by 20 ml each, and the herbicidal active ingredient concentration in the water was analyzed by HPLC (high performance liquid chromatography).

The water was collected at an inner diameter of 1 cm and a length of 8 c.
Using a glass tube with a length of 5 m, gently put the glass tube into the surface water to a depth of 5 cm, put a rubber stopper on the top of the glass tube, gently pull out, collect about 4 ml of the surface water, and perform this operation at the same point. The method was repeated twice to collect a total of 20 ml of water per point. Then, the diffusivity was represented by the ratio to the theoretical water concentration when the herbicidal active ingredient was uniformly dispersed in the water in the test plot by the following formula.

[0076]

(Equation 2)

The results are shown in Table 3 for Examples and Table 4 for Comparative Examples.

[0078]

[Table 1]

[0079]

[Table 2]

[0080]

[Table 3]

[0081]

[Table 4]

Claims (5)

[Claims] 1. A storage stabilizer of a water-based suspension formulation for direct application to flooded submerged rice fields, comprising a modified polyvinyl alcohol, containing water as a medium and containing a herbicidal active ingredient, and a water surface spreader for application. 2. The solubility in water at 20 ° C. is 100 ppm.
An aqueous suspension formulation for direct application to flooded sewers, comprising the following herbicidal active ingredients, modified polyvinyl alcohol and water. 3. The solubility in water at 20 ° C. is 100 ppm.
The following herbicidal active ingredients, modified polyvinyl alcohol,
An aqueous suspension formulation for direct application in flooded sewage fields, comprising a high boiling point solvent and water. 4. The storage stabilizer of the aqueous suspension formulation for direct application in flooded submerged rice fields according to claim 1, wherein the modified polyvinyl alcohol is a polyvinyl alcohol having an alkyl group at a terminal. Water surface expander. 5. The aqueous suspension formulation for direct spraying of a flooded paddy field according to claim 2, wherein the modified polyvinyl alcohol is a polyvinyl alcohol having an alkyl group at a terminal.