JPH07252103A - Wettable powder for disinfecting seed - Google Patents

Abstract

PURPOSE:To obtain wettable powder for disinfecting seeds capable of readily redispersing precipitates formed in preparing a highly diluted liquid with an amount of water of a low multiple using a weak stirring power. CONSTITUTION:This wettable powder for disinfecting seeds comprises (A) an agrochemically active ingredient, e.g. benomyl, thiabendazole, MBC, thiophanate methyl, thiuram or basic copper chloride, (B) at least one selected from urea, saccharides and modified starches having >=10% solubility in water at 20 deg.C as a water-soluble extender and (C) a nonignic surfactant (e.g. polyoxyethylene sorbitan ester of a fatty acid) and/or an anionic surfactant (e.g. lignin sulfonate). The ingredient (C) is added in an amount so as to provide a surface tension of a diluted liquid prepared by dispersing the resultant wettable powder in water in an amount of 10 times within the range of 25-55mN/m at 20 deg.C and the amount is usually 0.05-5 pts.wt., preferably 0.1-3 pts.wt. based on 1 pt.wt. ingredient (A).

Description

Detailed Description of the Invention

[0001]

[Object of the Invention]

TECHNICAL FIELD The present invention relates to a seed disinfectant wettable powder containing a pesticidal active ingredient for seed disinfection, which is prepared by diluting the wettable powder with water to obtain a highly concentrated diluted solution. The present invention relates to a wet disinfectant for seed disinfection, which can redisperse a precipitated solid precipitate in water by simple stirring or shaking.

[0002]

As a method of seed disinfection with a seed disinfectant, a wettable powder is prepared from a pesticidal active ingredient for seed disinfection, a surfactant and a mineral carrier such as clay, and the wettable powder is prepared with water for 20 to 200 times. Double (19-19 parts of water for 1 part by weight of wettable powder)
It is generally performed by diluting the seed paddy with a diluting solution diluted to 9 parts by weight).

On the other hand, in order to disinfect a large amount of seeds with a drug in a labor-saving manner, a diluting solution prepared by diluting a wettable powder with water 3 to 20 times (hereinafter, referred to as "high-concentration dilution" in comparison with conventional diluting solutions Liquid)), a method of spraying 3% of the dry seed weight on seeds by using a sprayer for seed disinfection has become popular. However, when diluting a conventional wettable powder prepared by using fine powder of mineral substances such as clay as a carrier to prepare a high-concentration diluting solution and spraying seeds, the diluting solution must be constantly stirred. A fine powder of mineral matter or a suspension of pesticide active ingredient particles precipitates in the diluent. Moreover, when the highly concentrated diluting liquid remains in the liquid medicine tank or the passage of the liquid medicine of the spraying device after the work is completed, if this diluting liquid is left to stand, a precipitate is accumulated in the diluting liquid to form a hard cake. Therefore, in such a case, it is not easy to redistribute it, and it is extremely difficult to restart the spraying device.

On the other hand, in order to improve the dispersibility of a diluting solution of a wettable powder, a wettable powder containing a mineral carrier such as clay has been used as a dispersant for polyoxyethylene polyoxypropylene block polymer sulfate ammonium salt. (Japanese Patent Publication No. 02-44802) and polyoxyethylene tristyrylphenyl ether sulfate sodium salt (JP-A-63-543)
No. 01) is known.

Further, (a) 5-ethyl-5,8-dihydro-8-oxo-1,3-dioxolo (4,5-g) quinoline-7-carboxylic acid is contained as an agrochemical active ingredient, and (b) ) A wettable powder containing a water-soluble inorganic salt such as an alkali metal or ammonium sulfate, nitrate or chloride and (c) a surfactant is used to dilute with a small volume of water to obtain a highly concentrated diluent. It is known that when this is done, a wettable powder for seed treatment, which does not cause problems such as hard cake, can be obtained (JP-A-5-124914).

Agrochemical active ingredients, anionic surfactants such as sodium lignin sulfonate, diatomaceous earth,
When diluting a water dispersible pesticide for seed treatment consisting of an inert carrier such as synthetic hydrous silicic acid, saccharides, starch, and dextrin with water, a higher fatty acid ester of polyoxyalkylene, especially a montanic acid ester thereof, is added to disinfect the seed. A method for preparing a water-diluted solution of a hydrating agent is known (Japanese Patent Laid-Open No. 5-339104).

[0007]

However, when these existing wettable powders are used as a high-concentration diluting solution for seed spraying, they are not always satisfactory in terms of redispersibility of precipitates once formed. . Therefore, it is desired to develop a wettable powder for seed disinfection that does not have such drawbacks.

Under these circumstances, the object of the present invention is to
It is an object of the present invention to provide a wettable powder for seed disinfection, which can easily redisperse a precipitate generated when a highly concentrated diluted solution is prepared by diluting with water.

[0009]

[Constitution of the invention]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above problems. As a result, when a wettable powder having the composition and characteristics shown below was prepared, even if a high-concentration diluting solution was prepared with water to give various concentrations, in any case, when diluted with water. The present invention has been completed by finding that the precipitate formed in the above can be easily redispersed by stirring.

That is, the gist of the present invention is that
From the following composition (1), that is, an agrochemical active ingredient, as a water-soluble extender, at least one selected from urea, saccharides and modified starches, a nonionic surfactant and / or an anionic surfactant. And a surface tension of a dilute solution obtained by dispersing the wettable powder in 10 times by weight of water at 20 ° C.
A wettable powder for seed disinfection, comprising a surfactant in an amount of 5 to 55 mN / m.

Next, the wettable powder for disinfecting seeds of the present invention will be specifically described.

The pesticidal active ingredient of the present invention can be used as long as it is a pesticidal active ingredient used for controlling seed diseases such as rice bran disease, rice sesame leaf blight, and pests by seed disinfection.
These may be used alone or in combination of two or more. Examples of such agrochemical active ingredients include the following. (A) Methyl-1- (n-butylcarbamoyl) -2-
Benzimidazole carbamate (hereinafter referred to as "benomyl") (b) 2- (4-thiazolyl) benzimidazole (hereinafter referred to as "thiabendazole") (c) 2- (methoxycarbonylamino) benzimidazole (hereinafter referred to as "MBC") (d ) 1,2-bis (3-methoxycarbonyl-2-thioureido) benzene (hereinafter “thiophanate methyl”)
(F) Bis (dimethylthiocarbamoyl) disulfide (hereinafter referred to as “thiuram”) (f) Basic copper chloride (to) cupric hydroxide (thi) (N-propyl-N- [2- (2, 4,6-Trichlorophenoxy) ethyl] imidazole-1-carboxamide (hereinafter referred to as “prochloraz”) (i) (E) -4-chloro-α, α, α-trifluoro-N- (1-imidazole-1- Il-2-propoxyethylidene) -o-toluidine (hereinafter referred to as "triflumizole") (nu) 2- (4-chlorobenzyl) -5-isopropyl-1- (1H-1,2,4-triazole-1) -Ylmethyl) -1-cyclopentanol (hereinafter referred to as "ipconazole") (l) 0,0-dimethyl-0- (3-methyl-4-nitrophenyl) thiophosphate (hereinafter Below "Fenitrothion")

The chemical names of the compounds (a) to (i) and (l) and the common names in () are "Agricultural Chemicals Handbook" (July 30, 1992, published by the Japan Plant Protection Association).
Etc., and the compound of (nu) is described in JP-A-1-935.
Compounds described in JP-A-74, etc., respectively.

The content of the agrochemical active ingredient in the wettable powder according to the present invention is not particularly limited, but is 5 to 50% by weight in the total composition of the wettable powder.

Urea, saccharides or modified starches can be used as the water-soluble bulking agent to be incorporated in the wettable powder according to the present invention. The sugars or modified starches that can be effectively used have a solubility in water at 20 ° C. of 10 or less.
% Or more of sugars and modified starches. Specifically, sugars include glucose, sucrose, fructose, lactose and the like. As modified starches, dextrin,
Examples thereof include acid-decomposed starch, oxidized starch, pregelatinized starch and starch derivatives.

In the wettable powder of the present invention, these sugars and modified starches may be used alone or in combination of two or more kinds. Further, these water-soluble extenders are used in an amount of 0.2 to 20 parts by weight, preferably 0.
It can be mixed in a ratio of 5 to 5 parts by weight. In addition, it is preferable to contain the wettable powder in a proportion of 25 to 90% by weight in the total composition.

The surfactant used in the present invention includes:
A nonionic or anionic surfactant,
These two agents can be used in combination, and in each case, the wettable powder of the present invention is not particularly limited as long as it is usually used for imparting hydratability and wettability. For example, the following may be mentioned.

Examples of nonionic surfactants Polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene arylphenyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sorbitan fatty acid ester, sorbitan fatty acid ester, polyethylene glycol Examples thereof include polypropylene glycol block polymers, and polyoxyethylene sorbitan fatty acid esters and polyoxyethylene aryl phenyl ethers are preferable.

Examples of anionic surfactants Alkyl sulfate, polyoxyethylene alkylphenyl ether sulfate, polyoxyethylene alkyl ether sulfate, polyoxyethylene arylphenyl ether sulfate, polyoxyethylene arylphenyl ether sulfate ammonium salt , Polyethylene glycol polypropylene glycol block polymer sulfate, lignin sulfonate, alkyl naphthalene sulfonate, alkyl naphthalene sulfonate formalin condensate, naphthalene sulfonate formalin condensate, alkylbenzene sulfonate, polyoxyethylene arylphenyl ether sulfonate salt, polyoxyethylene arylphenyl ether phosphate, etc. However, lignin sulfone is preferred. DOO, naphthalene sulfonate formalin condensate, polyoxyethylene aryl phenyl ether sulfates, polyoxyethylene aryl phenyl ether phosphates.

These two kinds of surfactants can be used in any combination. An example of the preferable combination is the combined use of polyoxyethylene sorbitan fatty acid ester as the nonionic surfactant and lignin sulfonate or naphthalene sulfonate formalin condensate as the anionic surfactant.

These surfactants are prepared by adding 10 parts by weight of water to 1 part by weight of the wettable powder of the present invention, either alone or in combination with nonionic or anionic surfactants. The surface tension of the diluted solution (diluted solution in water of 10 times weight) obtained by dispersion is 25 to 55 mN / m at 20 ° C.
An amount sufficient to be in the range of (millinewton / meter) may be added to the wettable powder. The amount thereof is 0.05 to 5 parts by weight, preferably 0.1 to 3 parts by weight, based on 1 part by weight of the agricultural chemical active ingredient. Further, the amount of the surfactant may be 0.5 to 50% by weight, preferably 1 to 15% by weight, based on the total composition of the wettable powder from the viewpoint of its effect and economy.

The reason why the amount of the surfactant used should be taken into consideration is that the surface tension of the diluting solution is 25 mN / m at 20 ° C.
If the amount is less than the above, the dispersibility of the solid particles becomes poor and the precipitate becomes hard. Conversely, if the surface tension of the diluting liquid exceeds 55 mN / m at 20 ° C, the appropriate hydration property, dispersibility, and adhesion to seeds are not obtained. It may be that the redispersibility of the precipitate becomes poor as it is not obtained.

When the pesticide active ingredient and the surfactant are liquid, an oil absorbing agent can be added to support the liquid substance. In this case, the liquid pesticidal active ingredient and the surfactant are first added, and the oil absorbent may be added thereto, or the liquid may be supported by the oil absorbent by adding the oil absorbent in reverse. The pesticidal active ingredient and the surfactant may be used in a different order by absorbing oil into the oil absorbent. Examples of such oil absorbing agents include finely divided silicic acid commonly referred to as white carbon or silica, zeolite, diatomaceous earth, and the like.

To prepare the wettable powder for spraying of the present invention, the pesticidal active ingredient, the nonionic surfactant and / or the anionic surfactant, and the water-soluble bulking agent can be prepared in the same manner as in ordinary wettable powders. If necessary, the liquid pesticidal active ingredient and the surfactant may be preliminarily supported alone or both on the above oil absorbing agent, or other auxiliary agents may be added and uniformly mixed, and then finely ground. In addition, it can be prepared by an ordinary apparatus for preparing a wettable powder, and no special apparatus is required. In this case, as a method of fine pulverization,
Examples include air flow type pulverization such as a jet atomizer and impact type pulverization such as a hammer mill.

In the wettable powder of the present invention, as an auxiliary agent, for example, a stabilizer such as an antioxidant or a photodegradation inhibitor,
If necessary, one type or two or more types of foam inhibitors may be mixed and used.

[0026]

In the wettable powder of the present invention, the fine particles of the agrochemical active ingredient, the nonionic surfactant and / or the anionic surfactant and the water-soluble extender exhibit some interaction, which results in the emulsified dispersed particles. It is considered that weak agglomeration occurs between the particles, the particles become apparently large, and the particles become a precipitate in a weak agglomeration state and do not become dense, so that they can be well redispersed in water again by light stirring or shaking.

[0027]

EXAMPLES (Method for producing wettable powder of the present invention) Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

In the following, all "parts" mean parts by weight.

Example 1 20 parts of benomyl raw material, 5 parts of polyoxyethylene sorbitan fatty acid ester and 75 parts of urea were mixed and finely ground with a hammer mill to obtain a wettable powder.

Example 2 20 parts of benomyl drug substance, 3 parts of polyoxyethylene sorbitan fatty acid ester, 2 parts of lignin sulfonate [Nippon Paper Manufacturing Co., Ltd., trade name "Sun Extract P252" (registered trademark)] and 75 parts of urea were mixed. Finely pulverized with a hammer mill to obtain a wettable powder.

Example 3 Thiourum drug substance (30 parts), polyoxyethylene sorbitan fatty acid ester (3 parts), lignin sulfonate (4 parts) and dextrin (Matsuya Chemical Co., Ltd., trade name "Paindex # 3") (63 parts) were mixed, and a hammer mill was used. Was finely pulverized to obtain a wettable powder.

Example 4 Thiourum raw material (30 parts), polyoxyethylene sorbitan fatty acid ester (3 parts), naphthalene sulfonate formalin condensate (4 parts) and urea (63 parts) were mixed and finely ground with a hammer mill to obtain a wettable powder.

Example 5 Thiourum drug substance 30 parts, polyoxyethylene sorbitan fatty acid ester 3 parts, naphthalene sulfonate formalin condensate 4 parts and sucrose 63 parts were mixed and finely ground with a hammer mill to obtain a wettable powder. .

Example 6 20 parts of thiabendazole raw material, 10 parts of polyoxyethylene arylphenyl ether phosphate, 5 parts of finely divided silicic acid, 20 parts of urea and 45 parts of dextrin were mixed and finely ground with a hammer mill to obtain a wettable powder. Obtained.

Example 7 20 parts of thiabendazole drug substance, 5 parts of polyoxyethylene sorbitan fatty acid ester, 5 parts of lignin sulfonate, 20 parts of urea and 50 parts of sucrose were mixed,
Finely pulverized with a hammer mill to obtain a wettable powder.

Example 8 Thiabendazole drug substance 20 parts, polyoxyethylene arylphenyl ether phosphate 5 parts, urea 7
0 part and 5 parts of finely divided silicic acid were mixed and finely ground with a hammer mill to obtain a wettable powder.

Example 9 Thiabendazole drug substance 20 parts, polyoxyethylene arylphenyl ether phosphate 3 parts, sucrose
72 parts and 5 parts of finely divided silicic acid were mixed and finely ground with a hammer mill to obtain a wettable powder.

Example 10 Thiabendazole raw material (20 parts), polyoxyethylene arylphenyl ether phosphate (5 parts), dextrin (70 parts) and finely divided silicic acid (5 parts) were mixed and finely ground with a hammer mill to obtain a wettable powder.

Example 11 Thiabendazole drug substance 20 parts, polyoxyethylene arylphenyl ether phosphate 2 parts, urea 2
5 parts, 48 parts of sucrose and 5 parts of finely divided silicic acid were mixed and finely ground with a hammer mill to obtain a wettable powder.

[0040]

INDUSTRIAL APPLICABILITY When the wettable powder according to the present invention is used to prepare a high-concentration diluted solution diluted with water 3 to 20 times, even if it is left still after stirring once, the solid suspension in the diluted solution is Hard to settle. Further, even if a precipitate is formed after being left for a long time, the precipitate does not become hard and a hard cake does not occur. Therefore, the precipitate can be easily redispersed by stirring the high-concentration diluent containing the precipitate. Therefore, it is possible to easily restart the seed spraying device and perform the spraying work without clogging the chemical liquid tank or the chemical liquid flow path of the spraying machine. Moreover, the highly concentrated diluting liquid of the wettable powder of the present invention provides suitable hydration properties, dispersibility and adhesion to seeds.

Further, the wettable powder of the present invention has good redispersibility even when diluted 20 to 200 times with water as in the conventional seed disinfectant. Therefore, if seed paddy is immersed in this diluted solution, seed disinfection can be performed as in the conventional case.

Next, a test example for evaluating the surface tension of a water-diluted solution prepared by using the wettable powder of the present invention and the redispersibility of precipitates formed during water dilution will be shown.

Test Example 1 Surface Tension Measurement Test Wettable powder 1 prepared according to Examples 1 to 11 by placing 100 ml of distilled water at 20 ° C. in an Erlenmeyer flask of 200 ml capacity.
Add 0 g and stopper tightly. This is repeated 20 times, and the wettable powder is dispersed upside down to obtain a diluent. The surface tension of the diluted solution is measured at 20 ° C. with a CBVP type surface tensiometer A3 (manufactured by Kyowa Interface Science Co., Ltd.). The results are shown in Tables 1-2.

Test Example 2 Redispersibility Test 20 g of a wettable powder prepared according to Examples 1 to 11 was placed in a 200 ml capacity cylinder with a stopper, and tap water was added to add 20 g.
Make up to 0 ml. The cylinder is inverted 20 times repeatedly to prepare an aqueous dilution in which a wettable powder is dispersed in water. This is left to stand in a constant temperature water bath at 15 ° C. for 48 hours. After standing still,
Repeatedly invert the cylinder and determine the number of inversions required for the precipitate to completely redisperse in water. If the number of inversions is 20 times or less, the wettable powder can be put to practical use without hindering the spraying work by the spraying device.

The obtained results are shown in Tables 1-2.

Further, for comparison, a comparative wettable powder was prepared according to the method of Example 1, and the surface tension and redispersibility of the precipitates of these water diluted solutions were the same as in Test Examples 1 and 2. It was measured.
These results are also shown in Tables 3-4.

In the table, only pesticide active ingredients, water-soluble extenders and surfactants are shown, and the use of finely divided silicic acid used as an oil absorbing agent and its amount (from 100 parts by weight to the number of parts in the table) The description of the balance after subtracting the content) is omitted.

[0048]

[Table 1]

[0049]

[Table 2]

[0050]

[Table 3]

[0051]

[Table 4]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location A01N 43/78 Z 47/18 101 47/26 47/34 B 47/38 B 57/14 E 59 / 20 Z

Claims (3)

[Claims] 1. The following composition (1), that is, an agrochemical active ingredient, at least one selected from urea, saccharides and modified starches as a water-soluble extender, a nonionic surfactant and / or an anionic agent. A surface-active agent is a wettable powder, which is obtained by dispersing the wettable powder in 10 times by weight of water and has a surface tension of 2 at 20 ° C.
A wettable powder for seed disinfection, comprising a surfactant in an amount of 5 to 55 mN / m. 2. The wet disinfectant for seed disinfection according to claim 1, wherein the agricultural chemical active ingredient is the following (a) to (l). (A) Methyl-1- (n-butylcarbamoyl) -2-
Benzimidazole carbamate (b) 2- (4-thiazolyl) benzimidazole (c) 2- (methoxycarbonylamino) benzimidazole (d) 1,2-bis (3-methoxycarbonyl-2-thioureido) benzene (f) bis (Dimethylthiocarbamoyl) disulfide (f) Basic copper chloride (to) cupric hydroxide (thi) N-propyl-N- [2- (2,4,6-trichlorophenoxy) ethyl] imidazole-1-carboxamide (Ri) (E) -4-chloro-α, α, α-trifluoro-N- (1-imidazol-1-yl-2-propoxyethylidene) -o-toluidine (nu) 2- (4-chlorobenzyl ) -5-Isopropyl-1- (1H-1,2,4-triazol-1-ylmethyl) -1-cyclopentanol (l) 0, 0-dimethyl-0- (3-methyl-4-nitrophenyl) thiophosphate 3. The nonionic surfactant is polyoxyethylene sorbitan fatty acid ester, the anionic surfactant is lignin sulfonate, naphthalene sulfonate formalin condensate or polyoxyethylene arylphenyl ether phosphate, or nonionic. The wettable powder for seed disinfection according to claim 1, which is a mixture of a polyoxyethylene sorbitan fatty acid ester as a surfactant and a lignin sulfonate or naphthalene sulfonate formalin condensate as an anionic surfactant.