JP3506898B2 - Aqueous suspension formulation for direct application in flooded sewage fields - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a submerged sewage paddy field that can be sprayed by dropping the formulation into a paddy field as it is without diluting it with water, and can perform pre-transplantation treatment, simultaneous transplantation treatment, and post-transplantation treatment of rice. The present invention relates to an aqueous suspension preparation for direct application.

[0002]

2. Description of the Related Art Up to now, several aqueous suspension preparations in which herbicidal active ingredients are suspended and dispersed in water are known. For example, it relates to an aqueous suspension preparation 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), fine particles of 10 μm or less. A slightly water-soluble herbicidal active ingredient is suspended in water to give a viscosity of 180 to 500 centipoise (20
℃), the initial water surface spreading speed is 4.0 cm / sec (20
℃) or more, the surface tension is 25.0 to 31.0 dyne / c
Water-suspended paddy field herbicide having physical properties of m (25 ° C.) (JP-A-62-87501), an average particle diameter of 0.5 to 5.0 μm, and a water solubility of 100 ppm (2
The herbicidally active compound having a surface tension of 36 to 65 dyne / cm (25 ° C) is suspended in water using a surfactant.
C.) relating to an aqueous herbicidal suspension formulation having physical properties (Japanese Patent Publication No. 7-47522), a herbicidal active compound, a surfactant, and water and having a surface tension of 35 to 65 dyne /
from an aqueous suspension preparation for weeding having a physical property of cm (25 ° C.) (JP-A-62-289502), a hydrophobic herbicidal component (butamiphos) and polyvinyl alcohol or gum arabic, and a thickener and water. Related to an oil-in-water suspension type herbicidal composition (JP-A-55-12470)
No. 8), relating to an aqueous suspension biocide composition comprising a paste-like or solid water-insoluble biocide having a melting point of 38 to 110 ° C., polyvinyl alcohol, a water-soluble thickener, and water (JP-A-61-1). No. 126001).

[0003]

The aqueous suspension formulation for direct spraying of flooded sewage paddy using water as a dispersion medium is safe because it can be dripped directly from the container to the paddy water without diluting with water when spraying the drug. The dosage form is excellent in terms of efficiency, economy, and labor saving. However, conventional aqueous suspension preparations for direct spraying in flooded paddy fields exert a sufficient herbicidal effect because dispersoids settle out during long-term storage and diffusion of herbicidal active ingredients in paddy water is insufficient. If not sprayed, or because the formulation contains surfactants such as nonionic surfactants, anionic surfactants, and cationic surfactants, the drug is likely to adhere to the rice plant during spraying, causing phytotoxicity. It was easy to cause problems such as.

Therefore, in place of the conventional aqueous suspension for direct spraying on flooded paddy fields, the formulation stability and the diffusibility of the herbicidal active ingredient in water at the time of spraying are excellent, and there is no chemical damage to rice plants. The development of a turbid formulation is desired, and the present invention is to provide an aqueous suspension formulation for direct spraying of flooded sewage fields that meets these needs.

[0005]

[Means for Solving the Problems] Therefore, the inventors of the present invention have conducted extensive studies for the purpose of improving drug stability and water-diffusibility, and preventing the drug from adhering to rice plants and preventing chemical damage. As a result, the solubility in water at 20 ° C is 100 pp
m or less herbicidal active ingredient and water-soluble as protective colloid agent
Aqueous suspension concentrates consisting of cellulose ether and water found to exhibit excellent effects for these purposes,
The present invention has been completed.

Further, by using a water-soluble cellulose ether as the protective colloid agent of the present invention, an aqueous suspension formulation for direct spraying of flooded sewage paddy was found which has good formulation stability and diffusibility in water. That is, the gist of the first invention is that the solubility in water at 20 ° C. is 100 pp.
herbicidal active ingredient of m or less and water as a protective colloid agent
An aqueous suspension preparation for direct spraying in flooded paddy fields, which comprises soluble cellulose ether and water.

The herbicidal active ingredient which can be used in the present invention may be any herbicidal active ingredient having a solubility in water at 20 ° C. of 100 ppm or less, and there is no problem even if one or two or more kinds thereof are used in combination.

Examples of such herbicidal active ingredients include:
MCPB, phenothiol, clomeprop, naproanid, CNP, clomethoxonil, bifenox, benchocarb, esprocarb, dimepiperate, butachlor, pretilachlor, tenilchlor, bromobutide, mefenacet, dimuron, bensulfuron-methyl, pyrazosulfuron-ethyl, imazosulfuron,
Dimetamethrin, oxadiazone, pyrazolate, pyrazoxifene, benzophenap, dithiopyr, piperofos, ACN, simmethyline, pyributycarb, 1H-
Pyrazole-5-sulfonamide, N-(((4
6-dimethoxypyrimidin-2-yl) aminocarbonyl))-1-methyl-4- (2-methyl-2H-tetrazol-5-yl) (azimuthulfuron), 1-{[o
-(Cyclopropylcarbonyl) phenyl] sulfamoyl} -3- (4,6-dimethoxy-2-pyrimidinyl) urea (AC-140), 1- (2-chlorobenzyl) -3- (α, α-dimethyl-benzyl ) Urea (J
C-940), 3- (4,6-dimethoxy-1,3,5
-Triazin-2-yl) -1- [2- (2-methoxyethoxy) phenylsulfonyl] -urea (cinosulfuron), 3- (4,6-dimethoxypyrimidin-2-yl) -1- (2-ethoxyphenoxy) Sulfonyl) urea (ethoxysulfuron), 3- [4-chloro-5-
(Cyclopentyloxy) -2-fluorophenyl]-
5-isopropylidene-oxazolidine-2,4-dione (KPP-314), butyl (R) -2- [4- (4
-Cyano-2-fluorophenoxy) phenoxy] propionate (cyhalofop-butyl), N, N-diethyl-3-mesitylsulfonyl-1H-1,2,4-triazole-1-carboxamide (CH-900), S −
(N- (4-chlorophenyl) -N-isopropylcarbamoylmethyl) -O, O-dimethyldithiophosphate (anilophos), methyl = 2-[(4,6-dimethoxypyrimidin-2-yl) oxy] -6- [1- (methoxyimino) ethyl] benzoate (KUH-92
0), 2- [2- (3-chlorophenyl) -2,3-epoxypropyl] -2-ethylindan-1,3-dione (MK-243), 4- (2-chlorophenyl) -N.
-Cyclohexyl-4,5-dihydro-N-ethyl-5
-Oxo-1H-tetrazole-1-carboxamide (NBA-061), 3- [1- (3,5-dichlorophenyl) -1-methylethyl] -2,3-dihydro-6
-Methyl-5-phenyl-4H-1,3-oxazine-
4-one (MY-100), 3- [2,4-dichloro-
5- (2-proponyloxy) phenyl] -5- (1,
1-dimethylethyl) -1,3,4-oxadiazol-2 (3H) -one (oxadiargyl) and the like.

The names of these compounds are the general names and the like described in "Agricultural Chemicals Handbook, 1994 Edition" (published by Japan Institute of Plant Protection).

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

In the case of anionic water-soluble cellulose ether, when a large amount of a metal salt or organic electrolyte is contained in the formulation or in the surface water of the field, the formulation is irreversible during storage due to exchange with these salts. When it becomes a gel or when it is applied to a flooded paddy field, there are problems such as droplets gelling and not spreading. In such a case, nonionic water-soluble cellulose ethers such as methyl cellulose, hydroxypropyl methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose are preferable.

As the water-soluble cellulose ether, three O atoms in one glucose residue contained in cellulose are used.
About 2 of the H groups are substituted with methoxy groups, and methyl cellulose containing 27 to 32% by weight of methoxy groups in the molecule, or hydroxy in which a part of the methoxy groups of methyl cellulose is further substituted with hydroxypropoxy groups. Propylmethyl cellulose may be mentioned. For example, as the methyl cellulose, the product name “Marporose M” manufactured by Matsumoto Yushi-Seiyaku Co., Ltd. (methoxy group substitution rate 27.5-3
1.5%, thermal gelation temperature 50 to 55 ° C., trade name “Metroze SM” manufactured by Shin-Etsu Chemical Co., Ltd. (methoxy group substitution rate 27.5 to 31.5%, thermal gelation temperature about 52 ° C.) As the hydroxypropyl methylcellulose, the product name "Marporose 60M" manufactured by Matsumoto Yushi-Seiyaku Co., Ltd.
P "(methoxy group substitution rate 28-30%, hydroxypropoxy group substitution rate 7-12%, thermal gelation temperature 58-64
C.), trade name "Marporose 65MP" (methoxy group substitution rate 27 to 30%, hydroxypropoxy group substitution rate 4 to
7.5%, thermal gelation temperature 62 to 68 ° C., trade name “Marporose 90MP” (methoxy group substitution rate 19 to 25%,
Hydroxypropoxy group substitution rate 4 to 12%, thermal gelation temperature 70 to 90 ° C, trade name "Marporose MP" (methoxy group substitution rate 16.5 to 20%, hydroxypropoxy group substitution rate 23 to 32%, thermal gel Temperature of 60 to 70 ° C.) and the like.

Other than these, water-soluble cellulose ethers usable in the present invention include the following. That is, hydroxyethylcellulose obtained by reacting ethylene oxide with cellulose, hydroxypropylcellulose obtained by reacting propylene oxide with cellulose, and monochloroacetic acid with alkali cellulose obtained by reacting caustic soda with cellulose,
For example, carboxymethyl cellulose obtained by substituting a part of hydroxyl groups of cellulose with a carboxyl group. Commercially available products of these water-soluble celluloses are, for example, hydroxyethyl cellulose as HEC Daicel (trade name of Daicel Chemical Industry Co., Ltd.), Fuji Heck (trade name of Fuji Chemical Co., Ltd.), and NATROSOL (product of Nissho Iwai Co., Ltd.). And the like, and examples of hydroxypropyl cellulose include Nisso HPC (trade name of Nippon Soda Co., Ltd.). As carboxymethyl cellulose,
Sunrose (trade name of Nippon Paper Industries Co., Ltd.), CMC Nippon (trade name of Japan CMC Co., Ltd.), Serogen (trade name of Daiichi Kogyo Seiyaku Co., Ltd.), CMC Daicel (manufactured by Daicel Chemical Industries Ltd.) Product name) and the like. The water-soluble cellulose ether is not limited to these, and there is no problem even if one or more of these are used in combination.

The content of the water-soluble cellulose ether in the preparation is 0.1 to 20% by weight, preferably 0.5 to 15% by weight.

Further, if necessary, as an auxiliary agent, for example, a thickener, an antifoaming agent, an antifreezing agent, an antiseptic / antifungal agent, a stabilizer for the herbicidal active ingredient and the like can be used.

Any thickening agent may be used, for example, xanthan gum, tragacanth gum, casein, dextrin, colloidal hydrous aluminum silicate, colloidal hydrous magnesium silicate, colloidal hydrous aluminum magnesium silicate. However, the present invention is not limited thereto, and one or more of these may be used in combination without any problem.

As antifoaming agents, silicon-based and fatty acid-based substances, etc., antifreezing agents such as ethylene glycol, propylene glycol and glycerin, and antiseptic / antibacterial agents such as potassium sorbate and p-chloro-metaxylenol. As the stabilizer for the herbicidal active ingredient such as butyl p-oxybenzoate, an antioxidant, an anti-UV agent, a crystal precipitation inhibitor, etc. may be added, but the stabilizers are not limited to the auxiliary agents exemplified here. Not a thing.

The aqueous suspension preparation of the present invention can be used regardless of the water depth as long as the paddy field after the substituting work is in a flooded state. In other words, from the state where there is a slight water layer on the soil surface, such as when planting rice,
Spraying is possible until the soil surface is completely dry, up to a condition of 5 cm of water. It can also be used when irrigation water enters. It may be under the condition of little water at the time of rice planting, such as dropping treatment at the same time as rice planting,
If treated, the herbicidal active ingredient diffuses to some extent and becomes even more uniform by the subsequent water entry, and a sufficient herbicidal effect can be exhibited.

Further, it can be sprayed at any time before, during or after transplanting rice. It can also be applied to directly flooded paddy rice.

For spraying the aqueous suspension preparation of the present invention, the stock solution may be used without further diluting it with water or a small amount of water may be used to prepare a highly concentrated diluted solution of 2 to 5 times, and the solution may be added dropwise to the paddy field. It does not have to be evenly spread over the entire surface of the paddy field as with granules. In addition, as a spraying method, the stock solution or the high-concentration diluted solution may be put into a plastic container having a capacity of, for example, 500 ml and shaken by hand, or sprayed or sprayed by using a pressure type spraying machine. Further, it is also possible to spray or drip in the air from an RC helicopter that has become widespread in recent years. In addition, when the irrigation water flows in, a drop treatment may be performed on the inflow water at the water intake (water port) of the paddy field, and the irrigation water may be poured into the paddy field together with the inflow water.

The application amount per unit area of the aqueous suspension preparation of the present invention is not particularly limited, but in the case of spraying the undiluted solution, it is 0.05 per 10 ares from the viewpoint of labor and labor efficiency of the spraying work.
It ranges from 1 to 2 liters, preferably 0.
It is in the range of 1 liter to 1.5 liters. When sprayed with a high-concentration diluted solution (2 to 5 times), the amount is 0.1 to 6 liters, preferably 0.2 to 5 liters per 10 ares.

[0022]

EXAMPLES Next, examples of the aqueous suspension preparation for direct spraying of flooded sewage fields of the present invention will be given, but the present invention is not limited thereto.

All parts in the examples represent% by weight.

Example 1 6 parts of sodium carboxymethylcellulose (trade name "CMC Daicel 1130" manufactured by Daicel Chemical Industries, Ltd.) was dissolved in 57 parts of water, and Jet-O-miz was prepared in advance.
ER (trade name of Seishin Enterprise Co., Ltd.), 27 parts of CNP raw material finely pulverized to an average particle diameter of 4 μm and 10 parts of 2% xanthan gum aqueous solution were added and mixed using a three-one motor, and then TK auto homomixer. (Nippon Tokushu Kika Kogyo Co., Ltd.) was used and stirred at 5000 rpm for 20 minutes to obtain a uniform aqueous suspension preparation.

Example 2 66 parts of water was mixed with methyl cellulose [trade name "Marpo Rose M
-25 "(methoxy group substitution rate 27.5 to 31.5%, manufactured by Matsumoto Yushi Co., Ltd.)] 4 parts were dissolved, 21 parts of Bifenox raw material and 3 parts of propylene glycol were added, and pulverization was performed using a Dynomill KDL type. The liquid was pulverized so that the average particle diameter of the liquid was 3 μm.

As the grinding medium, the diameter of 0.
Hard glass beads of 7 to 1.2 mm were used. To this pulverized liquid, 6 parts of a 2% xanthan gum aqueous solution was added and uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

Example 3 Of the formulation composition of Example 2 , water-soluble cellulose ether was used.
As shown in Table 1 , prepared in accordance with Example 2 except that hydroxypropylmethyl cellulose "trade name Marporose 90MP-4000" (methoxy group substitution rate 19 to 25%, hydroxypropoxy substitution rate 4 to 12%) was used, and the aqueous solution was prepared. A suspension formulation was obtained.

Example 4 Hydroxypropylmethylcellulose [trade name "Marporose 65MP-400" (65% water) (methoxy group substitution rate 27 to 30%, hydroxypropoxy group substitution rate 4 to
7.5%, manufactured by Matsumoto Yushi Co., Ltd.)], and 2 parts of the same are dissolved in advance using a Jet-O-mizer to obtain an average particle diameter of 4 μm.
27 parts of CNP drug substance finely pulverized to m and 6 parts of 2% xanthan gum aqueous solution were added and mixed using a three-one motor, and then stirred at 5000 rpm for 20 minutes using a TK auto homomixer to obtain a uniform aqueous suspension preparation. Obtained.

Example 5 Of the formulation composition of Example 4 , water-soluble cellulose ether was used.
As shown in Table 1 , methyl cellulose [trade name "Marporose M-400" (methoxy group substitution rate 27.5-3
1.5%)] was prepared according to Example 4 to obtain an aqueous suspension preparation.

Example 6 Hydroxypropylmethylcellulose [trade name "Marporose 60MP-50" (8-30 parts of methoxy group substitution rate, hydroxypropoxy group substitution rate 7) was added to 83.8 parts of water.
-12%, manufactured by Matsumoto Yushi Co., Ltd.)], 4.2 parts of phenothiol raw material and 3 parts of propylene glycol were added, and the average particle size of the pulverized liquid was 3 μm using Dynomill KDL type. Finely crushed. At this time, pulverization was performed while cooling so that the temperature of the pulverized liquid did not exceed 20 ° C.

As the crushing medium, a diameter of 0.
Hard glass beads of 7 to 1.2 mm were used. To this pulverized liquid, 6 parts of a 2% xanthan gum aqueous solution was added and uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

Example 7 In the formulation composition of Example 6 , the water-soluble cellulose ether was methylcellulose [trade name "Marporose 90M-2000" (methoxy group substitution rate 27.5) as shown in Table 1.
~ 31.5%, manufactured by Matsumoto Yushi Co., Ltd.) 1 part and water 8
An aqueous suspension preparation was obtained in the same manner as in Example 6 , except that the amount was changed to 5.8 parts.

Example 8 Hydroxypropylmethyl cellulose [trade name "Marporose 65MP-4000" (methoxy group substitution rate 27 to 30%, hydroxypropoxy group substitution rate 4 to 7.5%, Matsumoto Yushi Co., Ltd.) was added to 75.5 parts of water. 0.5 parts), 21 parts of bifenox raw material and 3 parts of ethylene glycol were added, and finely pulverized using a 4-cylinder sand grinder so that the average particle size of the pulverized liquid was 3 μm. An aqueous suspension formulation was obtained.

As the crushing medium, a diameter of 0.
Hard glass beads of 7 to 1.2 mm were used.

Example 9 69.5 parts of water was charged with hydroxypropylmethylcellulose [trade name "Marporose 60MP-4000" (methoxy group substitution rate 28-30%, hydroxypropoxy group substitution rate 7-12%, manufactured by Matsumoto Yushi Co., Ltd.). ] 0.5 part was dissolved, 27 parts CNP raw material and 3 parts ethylene glycol were added, and finely pulverized using a 4-cylinder sand grinder so that the average particle size of the pulverized liquid was 3 μm, and a uniform aqueous suspension was prepared. A turbid formulation was obtained.

As the grinding medium, the diameter of 0.
Hard glass beads of 7 to 1.2 mm were used.

Example 10 Hydroxyethyl cellulose (trade name "HE
C Daicel SP200 "manufactured by Daicel Chemical Industries, Ltd.)
5 parts of the mixture was dissolved, 21 parts of bifenox raw material and 3 parts of propylene glycol were added, and the mixture was finely pulverized using a Dynomill KDL type so that the average particle size of the pulverized liquid was 3 μm.

The diameter of the grinding medium is 0.7.
Hard glass beads of ~ 1.2 mm were used. To this pulverized liquid, 8 parts of a 2% xanthan gum aqueous solution was added and uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

Example 11 In the formulation composition of Example 10 , water-soluble cellulose ether was made into 1 part of hydroxypropyl cellulose (trade name "Nisso HPC-M" manufactured by Nippon Soda Co., Ltd.) as shown in Table 1 , and water was added. Was prepared according to Example 10 except that the amount was 67 parts to obtain an aqueous suspension preparation.

Example 12 Of the formulation composition of Example 10 , 3 parts of water-soluble cellulose ether as shown in Table 1 was used as carboxymethyl cellulose (trade name "CMC Daicel 1207" manufactured by Daicel Chemical Co., Ltd.), and 65 parts of water was used. Example 10 except that
To prepare an aqueous suspension preparation.

Example 13 2 parts of hydroxypropyl cellulose (trade name "Nisso HPC-M" manufactured by Nippon Soda Co., Ltd.) was dissolved in 78 parts of water, and an average particle size of 2 was previously prepared using a Jet-O-mizer.
12 parts of pyributicarb raw material finely pulverized to μm, 3 parts of propylene glycol, 5 parts of 2% xanthan gum aqueous solution were added and mixed using a three-one motor, and then stirred at 5000 rpm for 20 minutes using a TK auto homomixer to obtain a uniform mixture. An aqueous suspension formulation was obtained.

Example 14 In the formulation composition of Example 13 , water-soluble cellulose ether was changed to hydroxyethyl cellulose (trade name "HEC Daicel SP200" manufactured by Daicel Chemical Industries, Ltd.) as shown in Table 1 , and water was added to 77 parts. Example 1 except that
Preparation was carried out according to 3. to obtain an aqueous suspension preparation.

Example 15 Of the formulation composition of Example 13 , 1 part of water-soluble cellulose ether as shown in Table 1 was used as carboxymethyl cellulose (trade name "CMC Daicel 1207" manufactured by Daicel Chemical Co., Ltd.), and 79 parts of water was used. Example 13 except that
To prepare an aqueous suspension preparation.

Example 16 Carboxymethyl cellulose (trade name "CM
C Daicel 1207 "manufactured by Daicel Chemical Industries, Ltd.) 6
Parts were dissolved, 12 parts of pretilachlor base material and 5 parts of ethylene glycol were added, and finely pulverized using a Dynomill KDL type so that the pulverized liquid had an average particle diameter of 3 μm. At this time, pulverization was performed while cooling so that the temperature of the pulverized liquid did not exceed 20 ° C.

As the crushing medium, a diameter of 0.
Hard glass beads of 7 to 1.2 mm were used. To this pulverized liquid, 3 parts of a 2% xanthan gum aqueous solution was added and uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

[0046] Example 17 Of the pharmaceutical compositions of Examples 16, Examples except that the water-soluble cellulose ether was hydroxyethylcellulose as shown in Table 2 (trade name "HEC DAICEL EP250" manufactured by Daicel Chemical Industries, Ltd.) 16 To prepare an aqueous suspension preparation.

Example 18 In the formulation composition of Example 16 , 4 parts of water-soluble cellulose ether was prepared as shown in Table 2, and hydroxypropyl cellulose (trade name "Nisso HPC-L" manufactured by Nippon Soda Co., Ltd.) was added, and water was added. Was prepared according to Example 16 except that the amount was changed to 76 parts to obtain an aqueous suspension preparation.

Example 19 Hydroxyethyl cellulose (trade name "HE
C Daicel EP500 "manufactured by Daicel Chemical Industries, Ltd.)
1 part was dissolved, 5 parts of a raw material for tenylchlor and 5 parts of propylene glycol were added, and the mixture was finely pulverized using a 4-cylinder sand grinder so that the average particle size of the pulverized liquid was 3 μm.

The diameter of the grinding medium is 0.7.
Hard glass beads of ~ 1.2 mm were used. 10 parts of a 2% xanthan gum aqueous solution was added to this pulverized liquid, and the mixture was uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

Example 20 In the formulation composition of Example 19 , water-soluble cellulose ether was made into 2 parts of hydroxyethyl cellulose (trade name "HEC Daicel SP400" manufactured by Daicel Chemical Industries, Ltd.) as shown in Table 2 , and 78 parts of water was used. Aqueous suspension preparations were obtained by preparing according to Example 19 except that the parts were used.

Example 21 Example 19 except that the water-soluble cellulose ether was changed to carboxymethyl cellulose (trade name "CMC Daicel 1190" manufactured by Daicel Chemical Industries, Ltd.) as shown in Table 2 in the formulation composition of Example 19. Prepared according to
An aqueous suspension formulation was obtained.

Comparative Example 1 2 parts of polyoxyethylene nonylphenyl ether (trade name "Emulgen PI-20T" manufactured by Kao Corporation) was used as a surfactant in place of the sodium carboxymethyl cellulose of Example 1 , and 61 parts of water was used. Example except for
By the same composition and operation as in 1 , a uniform aqueous suspension preparation was obtained.

Comparative Example 2 In 66 parts of water, 2 parts of polyoxyethylene tristyryl phenyl ether phosphate (trade name "Solpol 7678" manufactured by Toho Chemical Industry Co., Ltd.) as a surfactant and ligninsulfonic acid sodium salt (trade name "Sorpol 904"
7K "manufactured by Toho Kagaku Kogyo Co., Ltd.) was dissolved, 21 parts of Bifenox raw material and 3 parts of propylene glycol were added, and finely pulverized using a Dynomill KDL type so that the pulverized liquid had an average particle diameter of 3 μm.

As the crushing medium, a diameter of 0.
Hard glass beads of 7 to 1.2 mm were used. To this pulverized liquid, 6 parts of a 2% xanthan gum aqueous solution was added and uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

Comparative Example 3 The procedure of Example 4 was repeated except that 2 parts of polyoxyethylene octyl phenyl ether (trade name "Solpol OP-14" manufactured by Toho Chemical Industry Co., Ltd.) was used as the surfactant instead of the hydroxypropylmethyl cellulose of Example 4. A uniform aqueous suspension preparation was obtained by the same composition and operation as in Example 4 .

Comparative Example 4 Instead of the hydroxypropylmethyl cellulose of Example 6 , polyoxyethylene tristyryl phenyl ether (trade name "SOPROPHOR S / 2 was used as a surfactant.
5 "manufactured by Rhone Poulin) Example except that 3 parts were used
A uniform aqueous suspension preparation was obtained by the same composition and operation as in 6 .

[0057] Comparative Example 5 Example 8 trade name alkylphenol ethylene oxide-propylene oxide block copolymer as a surfactant in place of hydroxypropyl methylcellulose (trade name "SOPROPHOR 805 / P" Rhone
A uniform aqueous suspension preparation was obtained by using the same composition and operation as in Example 8 except that 4 parts (manufactured by Poulin Co., Ltd.) was used and 72 parts of water was used.

Comparative Example 6 In 62 parts of water, 2 parts of polyoxyethylene styryl phenyl ether (trade name "Solpol T-20" manufactured by Toho Chemical Industry Co., Ltd.) as a surfactant and ligninsulfonic acid sodium salt (trade name "Solpol 9047K "Toho Chemical Industry Co., Ltd.) 2 parts were dissolved, and Bifenox drug substance 21
Part and propylene glycol 5 parts are added, and Dyno Mill KD
The L type was used to finely pulverize the pulverized liquid so that the average particle size was 3 μm.

The diameter of the grinding medium is 0.7.
Hard glass beads of ~ 1.2 mm were used. To this pulverized liquid, 8 parts of a 2% xanthan gum aqueous solution was added and uniformly mixed using a three-one motor to obtain an aqueous suspension preparation.

Comparative Example 7 Polyoxyethylene octyl phenyl ether (trade name "Solpol OP-10" Toho Chemical Industry Co., Ltd.) was used as a surfactant in place of the hydroxypropyl cellulose of Example 13 (trade name "Nisso HPC-M"). A uniform aqueous suspension preparation was obtained by the same composition and operation as in Example 13 except that 2 parts (manufactured by the company) were used.

Comparative Example 8 5 parts of polyoxyethylene styryl phenyl ether (trade name "Sorpol T-15" manufactured by Toho Chemical Industry Co., Ltd.) was used as a surfactant in place of the carboxymethyl cellulose of Example 16 and 75 parts of water was used. Example 1 except that
A uniform aqueous suspension preparation was obtained by the same composition and operation as in 6 .

Comparative Example 9 3 parts of polyoxyethylene polyoxypropylene block polymer (trade name "Pluronic P-85" manufactured by Asahi Denka Kogyo Co., Ltd.) was used as a surfactant instead of hydroxyethyl cellulose of Example 19 , and water was used. A uniform aqueous suspension preparation was obtained by the same composition and operation as in Example 19 except that the amount was 77 parts.

[0063]

EFFECTS OF THE INVENTION By carrying out the aqueous suspension preparation for direct spraying of flooded sewage fields of the present invention, the following action and effects are brought about. First, since the chemicals do not adhere to the rice body during spraying, there is little phytotoxicity to rice and a high herbicidal effect is exhibited. Second, the stability of the formulation is good for a long time,
Moreover, the diffusion of the herbicidal active ingredient in the paddy water is good. Third
Since it is a formulation containing water as a dispersion medium, there is little danger of ignitability, flammability, etc., and there is no environmental hygiene problem due to irritation to the human body or odor. Fourth, after substituting work, it can be sprayed before transplanting rice, at the same time as transplanting, and after transplanting. In particular, after transplanting rice, if it is in a flooded state, it can be sprayed at any time without diluting with water. All that is required is to drip the medicine from the ridge while it is still in the container, or to pour it into the water inlet and pour it along with the inflowing water.

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

Test Example 1 Paddy rice adhesion and phytotoxicity test 1/5
Fill paddy soil in a 000 ares Wagner pot and add water to form fertilizer (N: P: K = 17: 17: 17) 2
After mixing with g and performing decapitation, two 2.5-leaf stage paddy rice seedlings (variety: Nihonbare) were transplanted per pot. The test was carried out in 3 pots of one treatment group (total of 6 pots), and 5 days after transplanting the paddy rice, 50 μl of the aqueous suspension preparation prepared according to the example was placed in the center of the leaf blade of the second leaf of the paddy rice at 1 cm from the leaf surface. The number of strains in which the drug was attached to the leaf blades was examined by dropping from the height with a microsyringe. After 5 days from the chemical treatment, the degree of phytotoxicity to paddy rice was investigated according to the following criteria (the degree of phytotoxicity in Tables 1 and 2 is the average value of 6 strains). The results are shown in Tables 1 and 2 .

Criteria for investigation 0: No phytotoxicity 1: Remaining drug marks on the adhered part 2: Browning of 1/4 or less of the adherent leaves 3: Browning of 1/4 to 1/2 of the adherent leaves 4: 1 / of the adherent leaves 2 to 3/4 browned 5: 3/4 or more of the attached leaves browned 6: the attached leaves died 7: the attached leaves died, and 1/2 or less of the new leaves (fourth leaf) browned 8: attachment Leaves die, and more than 1/2 of new leaves (4th leaf) are browned 9: Attached leaves and new leaves die 10: Whole rice die

Test Example 2 Long-Term Storage Stability Test 30 mL of an aqueous suspension preparation prepared according to the Example was used in a volume of 3
It is put in a 0 ml (φ17 mm × length 180 mm) test tube, sealed with a stopper, and allowed to stand in a thermostatic chamber at 20 ° C. or 40 ° C. The separated state after 3 months at 20 ° C and 3 months at 40 ° C, the suspension layer in the test tube settled to the lower layer, and the height of the water layer (upper layer) and the whole layer (cm) ) Was measured and suspension stability was calculated by the following formula. The results are shown in Tables 1 and 2 .

[0068]

[Equation 1]

Test Example 3 Diffusivity Test One test section with an area of 9 (3 m × 3 m) (flood depth 5 c
m) was prepared, and the sample prepared according to the example was directly dropped onto the center (point A) from 1 m from the water surface with a pipette in an area equivalent to the treatment drug amount shown in Tables 1 to 4. After 3 hours from the treatment, the water from the water depth of 5 cm to the water surface at the center (point A) and the four corners (points B to E) of the test plot was respectively 2
Collect 0 ml each and check the herbicidal active ingredient concentration in water by HPLC.
Was analyzed.

It should be noted that water is sampled at an inner diameter of 1 cm and a length of 8 cm.
Using the glass tube of No. 5, gently insert the glass tube into the surface water to a depth of 5 cm, put a rubber stopper on the upper part of the glass tube, and gently pull out to collect about 4 ml of the surface water, and perform this operation at the same point.
The method of repeating 20 times and collecting a total of 20 ml of water per site was used. The diffusivity was expressed by the following formula as a ratio to the theoretical concentration in water when the herbicidal active ingredient was uniformly dispersed in water in the test plot.

[0071]

[Equation 2]

The results are shown in Tables 1 and 2 .

[0073]

[Table 1]

[0074]

[Table 2]

Front page continuation (51) Int.Cl. ⁷ Identification symbol FI A01N 39/02 A01N 39/02 A 43/08 43/08 C 47/22 47/22 Z (31) Priority claim number Japanese Patent Application No. 9- 79237 (32) Priority date March 14, 1997 (March 14, 1997) (33) Priority claiming country Japan (JP) Preliminary examination (56) Reference JP-A-63-107901 (JP, A) JP 61-180701 (JP, A) JP 61-24506 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) A01N 25/00-65/02

Claims (3)

(57) [Claims] 1. Solubility in water at 20 ° C. is 100 pp
Herbicidal active ingredient of less than m and water-soluble as protective colloid agent
An aqueous suspension preparation for direct spraying of submerged paddy fields , which comprises a soluble cellulose ether and water. 2. A water-soluble cellulose ethers according to claim 1 is non
An aqueous suspension preparation for direct spraying of submerged paddy fields , which is an ionic water-soluble cellulose ether. 3. The nonionic water-soluble cellulose dye according to claim 2.
Ether is methyl cellulose, hydroxypropyl methyl
Cellulose, hydroxyethyl cellulose or hydro
An aqueous suspension preparation for direct spraying of flooded paddy fields , which is xylpropyl cellulose .