JPH07291803A - Water-soluble granular agrochemical - Google Patents

Abstract

PURPOSE:To obtain a water-soluble granular agrochemical improved in storage stability of its active component without reducing the ready water solubility. CONSTITUTION:This water-soluble granular agrochemical contains a water-soluble active component, e.g. an active component having >=0.01g/ml, preferably >=0.1g/ml water solubility at 20 deg.C and a cyclodextrin, preferably a mixture of alpha-, beta-and gamma-cyclodextrins or a mixture of maltosyl-(a-, p-or gamma-)cyclo-dextrins in a ratio of 5 to 95wt.% active component and 1 to 94wt.% cyclodextrin. The water-soluble granular agrochemical may further contain a water-soluble weakly basic substance. As the water-soluble active component, cartap hydrochloride, nitenpyram, allethrin, acephate, ESP (oxydeprofos), vamidothion, DEP (trichlorfon), validamycin A, diquat and bialaphos are exemplified.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a stabilized water-soluble granule containing a water-soluble pesticidal active ingredient such as nitempyram. The formulation of the present invention is used for controlling pests in the field of agriculture.

[0002]

2. Description of the Prior Art Nitenpyram ((E) -N- (6
-Chloro-3-pyridylmethyl) -N-ethyl-N'-methyl-2-
Nitrovinylidene diamine) is an agricultural insecticide with excellent pest control ability, can be mixed with other insecticides or fungicides, and can be mixed with mineral powders, water-soluble carriers, extenders, etc. Then, it can be used as various solid preparations such as powders, granules, wettable powders, water solutions, granules and the like (JP-A-2-171). Among them, water-soluble pesticide granules are granules that dissolve completely and easily in water, and are excellent preparations in terms of easy handling, easy weighing, dust prevention, and easy application. . For example, an excellent tempiram-containing water-soluble granule containing lactose as a bulking agent has been proposed (JP-A-6-92803). Furthermore, it has been desired to develop water-soluble granules in which the degradation of nitempyram in the water-soluble pesticide granules is further suppressed and the nitempyram is more stabilized.

[0003]

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a novel water-soluble pesticide granule capable of suppressing the decomposition of a water-soluble pesticide active ingredient such as nitempyram. In particular, it is an object of the present invention to provide a granule having improved storage stability of a water-soluble pesticidal active ingredient without impairing the water-soluble granule's characteristic easy solubility in water.

[0004]

Means for Solving the Problems As a result of intensive studies for solving the above-mentioned problems, the present inventors unexpectedly unexpectedly added nitenpyram with a cyclodextrin compound and wet granulation. It was found that the stable water-soluble pesticide granules of Furthermore, the present inventors have found that stable water-soluble pesticide granules can be obtained even when applied to other water-soluble pesticide active ingredients other than nitempyram, and as a result of further studies, the present invention was completed. I arrived. That is, the present invention relates to (1) a water-soluble granule characterized by containing a water-soluble pesticide active ingredient and a cyclodextrin compound, (2) an item (1) further containing a water-soluble weakly basic substance Water-soluble granules according to (1) or (2), wherein the water-soluble pesticidal active ingredient (3) has a solubility in water at 20 ° C. of 0.01 g / ml or more. Granules, (4)
The water-soluble pesticide active ingredient is about 5 to 9 based on the total amount of the water-soluble pesticide active ingredient (1) or (2), wherein the water-soluble pesticide active ingredient is nitempyram.
A water-soluble granule according to item (1), which contains 5% by weight of cyclodextrin and about 1-94% by weight of cyclodextrin.

More specifically, (6) the water-soluble pesticide active ingredient is cartap hydrochloride, nitenpyram, allethrin,
Acephate, ESP (oxydepropos), bamidthione, DEP (trichlorfon), validamycin A,
1 selected from the group consisting of diquat and bialaphos
Or one or more water-soluble pesticide active ingredients (1)
Or the water-soluble granule according to the item (2), (7) the cyclodextrin compound is α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, or these cyclodextrins with any chemical modification, or The water-soluble granules according to (1) to (6), which is a mixture thereof, and (8) the cyclodextrin compound is α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, (mono, di or Tri) -methyl-α-cyclodextrin, (mono-, di- or tri) -methyl-β-cyclodextrin, (mono-, di- or tri) -methyl-γ-cyclodextrin, hydroxypropyl-α-cyclodextrin, hydroxypropyl -Β-cyclodextrin, hydroxypropyl-γ-cyclodextrin , Glucosyl -α
-Cyclodextrin, glucosyl-β-cyclodextrin, glucosyl-γ-cyclodextrin, maltosyl-α-cyclodextrin, maltosyl-β-cyclodextrin, maltosyl-γ-cyclodextrin, poly-α-cyclodextrin, poly-β- The water-soluble granules according to (1) to (6), which is one kind or a mixture of two or more kinds selected from the group consisting of cyclodextrin and poly-γ-cyclodextrin.

(9) The cyclodextrin compound is α-cyclodextrin, β-cyclodextrin and γ-
A mixture of cyclodextrins or maltosyl-α-cyclodextrin, a mixture of maltosyl-β-cyclodextrin and maltosyl-γ-cyclodextrin (1) to (6) water-soluble granules,
(10) The cyclodextrin compound is Toyoderin P (trade name) (manufactured by Asahi Foods Co., Ltd.) or Isoelite P
(Product name) (manufactured by Taiyo Fisheries Co., Ltd.) (1)-
The water-soluble granule according to (6), (11) the water-soluble weakly basic substance has a solubility in water at 20 ° C. of 0.05 g.
/ Ml or more and the pH of the aqueous solution at 25 ° C. is a water-soluble weakly basic substance having a pH of about 7.0 to 9.0, (12) Water-soluble granules according to (12) Water at 20 ° C. The water-soluble weakly basic substance having a solubility of 0.05 g / ml or more and a pH of the aqueous solution at 25 ° C. of about 7.0 to 9.0 is sodium thiosulfate, disodium hydrogen phosphate, sodium acetate, sodium carbonate. And at least one selected from the group consisting of and baking soda (11)
(13) The water-soluble granules according to (1) to (12), which further contains a surfactant.
(14) The water-soluble granule according to item (13), wherein the surfactant is a nonionic surfactant having an HLB value of about 9 to 12, and (15) a nonionic compound having an HLB value of about 9 to 12. The surfactant is polyoxyethylene nonyl phenyl ether,
Alternatively, a water-soluble weakly basic substance is contained in an amount of about 5 to 5 with respect to the total amount of the water-soluble granules (16) and the water-soluble granules (16), which is a block copolymer of ethylene oxide and propylene oxide.
90% by weight of the water-soluble granules according to item (2), and (17) the total amount of the water-soluble granules, the surfactant is contained in an amount of about 0.05 to 5% by weight. A water-soluble granule according to item (13) is provided.

The water-soluble pesticidal active ingredient used in the water-soluble granules of the present invention has, for example, a solubility in water at 20 ° C. of about 0.01 g / ml or more, preferably about 0.
Pesticide active ingredients of 1 g / ml or more are used, and as the pesticide active ingredients, for example, all pesticide active ingredients such as insecticides, fungicides, and herbicides are used. In the water-soluble granules of the present invention, one or more of these water-soluble pesticidal active ingredients can be used. Specific examples of the water-soluble pesticidal active ingredient used in the water-soluble granules of the present invention include the following. Solubility (water) Melting point (° C) -Insecticide-Cartap hydrochloride (cartap) 200 g / l 179-181 nitenpyram> 200 g / l 84-85 allethrin 500 g / l liquid acephate 650 g / L 91-92 ESP, oxydeprofos dissolution solution vamidothion (vamidothion) 4000 g / l 46-48 DEP, trichlorfon (trichlorfon) 154 g / l (25 ° C) 83-84-bactericide-validamycin A (validamycin A) ) Easily soluble 135-herbicide-diquat 700 g / l bialaphos> 1000 g / l Among the above water-soluble pesticidal active ingredients, the group consisting of cartap hydrochloride, acephate, nitenpyram and validamycin A. One or more selected from among these are preferable, and especially Nitempyram is It is suitable.

The cyclodextrin compound used in the water-soluble granules of the present invention is, for example, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, or those obtained by chemically modifying these cyclodextrins, or those And the like are used. Commercially available products are used as the α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin. Chemical modification of these α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin is generally performed to enhance the solubility of the cyclodextrin compound in water, an organic solvent, etc. It does not affect the original function. Therefore, the chemically modified cyclodextrin compound can be freely used in the water-soluble granules of the present invention. The type of chemical modification is not particularly limited, but for example, methyl groups of hydroxyl groups of glucose residues of cyclodextrin are (mono, di or tri) -methyl- (α-, β- or γ-). Cyclodextrin, hydroxypropylated hydroxypropyl- (α-, β- or γ-) cyclodextrin, such as glucose, maltose and other water-soluble substances introduced into the side chain of cyclodextrin glucosyl- (α-, β- or γ-) cyclodextrin, branched cyclodextrins such as maltosyl- (α-, β- or γ-) cyclodextrin, and poly- (α-, β- or γ-) obtained by crosslinking cyclodextrin with epichlorohydrin and the like to polymerize Cyclodextrin etc. are mentioned. Among them, glucosyl- (α-, β- or γ-) cyclodextrin, maltosyl- (α-, β- or γ-) cyclodextrin, etc. in which a water-soluble substance such as glucose or maltose is introduced into the side chain of cyclodextrin. The branched cyclodextrin of is preferable, and maltosyl- (α-, β- or γ-) cyclodextrin is particularly preferable.

In the water-soluble granules of the present invention, one of these cyclodextrin compounds can be used alone, and further, a mixture of two or more of these cyclodextrin compounds can be used. For example, a substance containing two or more of these cyclodextrin compounds in an appropriate ratio can be used. Examples of the substance containing two or more kinds of such cyclodextrin compounds include, for example, α-cyclodextrin, a mixture of β-cyclodextrin and γ-cyclodextrin, maltosyl-α-cyclodextrin, maltosyl-β-cyclodextrin and maltosyl-. Examples include a mixture of γ-cyclodextrin. Examples of the mixture of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin include commercially available toyoderin P.
(Trade name) (manufactured by Asahi Foods Co., Ltd.) and the like are used, and as a mixture of maltosyl-α-cyclodextrin, maltosyl-β-cyclodextrin and maltosyl-γ-cyclodextrin, for example, commercially available isoelite. P (trade name) (manufactured by Taiyo Fisheries Co., Ltd.) or the like is used. As the cyclodextrin compound used in the water-soluble granule of the present invention, among the above-mentioned ones, α
-Cyclodextrin, a mixture of β-cyclodextrin and γ-cyclodextrin, a mixture of maltosyl-α-cyclodextrin, maltosyl-β-cyclodextrin and maltosyl-γ-cyclodextrin, and the like are preferable. Specifically, as a mixture of α-cyclodextrin, β-cyclodextrin and γ-cyclodextrin, commercially available toyoderin P (trade name) is used.
(Manufactured by Asahi Foods Co., Ltd.) and the like are preferable, and as a mixture of maltosyl-α-cyclodextrin, maltosyl-β-cyclodextrin and maltosyl-γ-cyclodextrin, commercially available Isoeryte P (trade name).
(Manufactured by Taiyo Fisheries Co., Ltd.) and the like are preferable.

The content of the water-soluble pesticidal active ingredient used in the water-soluble granules of the present invention is usually about 5 with respect to the total amount of the granules.
˜95 wt%, preferably about 5-80 wt%. The content of the cyclodextrin compound used in the granules of the present invention is usually about 1 to 94% by weight based on the total amount of the granules,
It is preferably about 2 to 90% by weight. The water-soluble granules of the present invention may further contain water-soluble auxiliary agents such as water-soluble weakly basic substances, surfactants, dyes, binders and ultraviolet absorbers. Although the water-soluble weakly basic substance is not particularly limited, for example, the solubility in water at 20 ° C. is 0.05 g / ml or more, and the pH of the aqueous solution at 25 ° C. is about 7.0 to 9.0. And the like are preferable. Specifically, for example, one kind or two or more kinds selected from the group consisting of sodium thiosulfate, disodium hydrogen phosphate, sodium acetate, sodium carbonate and sodium bicarbonate is used. As the grade of the water-soluble weakly basic substance, any one of pharmacopoeia, industrial grade, food additive and the like can be used, and further, it can be used regardless of the presence or absence of bound water. Thus, when the water-soluble granules of the present invention are mixed with a water-soluble weakly basic substance, it is desirable to avoid the use of a water-soluble pesticide active ingredient which is unstable under alkaline conditions such as cartap hydrochloride.

The surfactant is not particularly limited, but a nonionic surfactant is relatively preferably used. Particularly, those having an HLB value in the range of about 9 to 12 are preferable from the viewpoint of solubility in water and moistening action. Specifically, for example, polyoxyethylene nonyl phenyl ether (eg: NP-85 (trade name), manufactured by Takemoto Yushi Co., Ltd.) or a block copolymer of ethylene oxide and propylene oxide (eg: Newpol PE). -64 (trade name), Sanyo Kasei Co., Ltd., etc. are used. As the dye, specifically, cyanine green G (trade name)
(Sumitomo Chemical Co., Ltd.) and the like are used. As the binder, specifically, dextrin, polyvinyl alcohol, gum arabic, sodium alginate, polyvinylpyrrolidone, glucose, sucrose, mannitol,
Sorbitol or the like is used. The content of these other water-soluble auxiliary agents in the water-soluble granules is such that the water-soluble weakly basic substance is usually about 5-90% by weight, preferably about 30-90% by weight, based on the total amount of the water-soluble granules. The range of the surfactant is usually about 0.05 to 5% by weight, preferably 1.0 to 3.
0% by weight, the dye usually being about 0.01-0.5.
%, Preferably in the range of 0.01 to 0.1% by weight, and the binder is usually about 0.5 to 10.0% by weight, preferably about 2.0 to 7.0% by weight. The range is selected.

The water-soluble granules of the present invention can be manufactured by a conventional method for manufacturing water-soluble granules. For example,
It can be manufactured using a spray drying method or a wet extrusion method. In the case of the spray drying method, usually about 50 to 1000 parts by weight of water is added to 100 parts by weight of the solid content of the formulation and dissolved therein, and the aqueous solution is spray-dried into powder granules to obtain a water-soluble granule. Specifically, a water-soluble pesticide active ingredient, a cyclodextrin compound, and if necessary, a water-soluble auxiliary agent such as a surfactant is dissolved in a sufficient amount of water to dissolve, and the aqueous solution is spray-dried. Obtain water-soluble granules. Alternatively, the water-soluble pesticide active ingredient and the cyclodextrin compound may be dissolved in an appropriate amount of water, and after spray drying, other water-soluble auxiliary agents such as a surfactant may be added and mixed. Further, this spray-dried product may be used for the wet extrusion granulation described below. The obtained granules have a particle size of about 0.05 to 1.0.
mm, preferably in the range of about 0.1-0.5 mm. In the case of wet extrusion granulation, water is usually used in an amount of about 1 to 10 parts by weight, preferably about 2 to 5 parts by weight, based on 100 parts by weight of solid formulation. Specifically, water-soluble pesticide active ingredient, cyclodextrin compound,
If necessary, a water-soluble auxiliary agent such as a surfactant is uniformly mixed with a mixer or the like. At this time, if the solid component has a large particle size and cannot be uniformly mixed, it may be coarsely pulverized to
It is desirable that the powder be made into an appropriate powder having a particle size of about 00 μm or less to facilitate the mixing operation. An appropriate amount of water is added to this mixture, and the mixture is further kneaded with a mixer to an extent suitable for extrusion granulation in the subsequent step. The kneaded product is granulated by a usual extrusion granulator and then dried. If necessary, the granulated product is sized to obtain a desired water-soluble granule. The sizing is performed within a range where the sieve does not pass through a sieve having an opening of 300 μm but passes through a sieve having a opening of 1,700 μm. The obtained granules have a major axis of about 0.5 to 10.0 mm, preferably about 0.5 to 5.0 mm.

The bulk density of the granules is about 0.1-1.
A range of 2 g / ml is preferred, even about 0.5-1.
A range of 0 g / ml is preferred. The water-soluble granules of the present invention obtained in this manner have substantially no phytotoxicity against plants and can be safely used without any harm to humans or animals during or after application. The water-soluble granules of the present invention have improved storage stability of the water-soluble pesticidal active ingredient without impairing the easy solubility in water which is a characteristic of the water-soluble granules. The water-soluble granules of the present invention are usually dissolved and diluted in water before use. The dilution is not particularly limited, but is usually about 100 to 2,000 times (about 1 g /
100 ml-1 g / 2,000 ml) is preferred. The amount of the diluted solution sprayed varies depending on the water-soluble pesticidal active ingredient, the target pest, the target farmland, the season, etc., but is usually about 500 to 1 per hectare such as paddy fields, fields such as tea fields and vegetable fields, orchards. 15,000 ml, preferably 1000
Sprinkle about 10,000 ml.

[0014]

EXAMPLES The present invention will be described in more detail below with reference to examples, reference examples and test examples, but the present invention is not limited to these examples. All% and parts used herein are% by weight and parts by weight unless otherwise specified.

Example 1 10 parts of nitenpyram and 90 parts of toyoderin P were dissolved in 400 parts of water, and this aqueous solution was made into solid granules by a spray dryer (Okawara Kakohki L-8), which was water-soluble containing 10% nitenpyram. A granule was obtained.

Example 2 Instead of 90 parts of toyoderin P of Example 1, 90 parts of isoerythite P was used, and spray drying was carried out in the same procedure as in Example 1 to obtain a water-soluble granule containing 10% of nitenpyram.

Example 3 Instead of 90 parts of toyoderin P of Example 1, 30 parts of toyoderin P and 60 parts of sodium acetate were used.
Spray drying with the same procedure as in Example 1 to obtain Nitenpyram 10
% Water-soluble granules were obtained.

[0015]

Example 4 Nitenpyram 10 parts, surfactant Newpol PE-1.0 1.0 part, dye cyanine green G
0.15 parts, toyoderin P 3.0 parts, baking soda 85.8
After thoroughly mixing 5 parts, 4 parts of water was added and kneaded with a kneader (Kikusui Seisakusho, KM-1.5). 0.8 of this mixture
Using a screen with a diameter of mm, the granules were extruded into granules with an extrusion granulator (Kikusui Seisakusho, RG-5M). The obtained granules were dried at 60 ° C for 1 hour to obtain a water-soluble granule containing 10% of nitenpyram.

Example 5 40 parts of nitenpyram and 60 parts of toyoderin P were dissolved in 400 parts of water, and this aqueous solution was made into solid granules by a spray dryer (Okawara Kakohki, L-8), which was water-soluble containing 40% of nitenpyram. A granule was obtained. This granule 2
5 parts, surfactant Newpol PE-64 1.0 part,
Dye Cyanine Green G 0.15 parts, baking soda 73.8
After thoroughly mixing 5 parts, 4 parts of water was added and kneaded with a kneader (Kikusui Seisakusho, KM-1.5). Then, extrusion granulation was carried out in the same manner as in Example 4 to obtain a water-soluble granule containing 10% of nitenpyram.

Reference Example 1 Lactose (90 parts) was used in place of the toyoderin P (90 parts) of Example 1 and spray-dried in the same manner as in Example 1,
A water-soluble granule containing 10% of nitenpyram was obtained.

Reference Example 2 Instead of 3.0 parts of toyoderin P and 85.85 parts of baking soda of Example 4, 5.0 parts of sucrose and 8 lactose
The content was adjusted to 3.85 parts and extruded and granulated in the same manner as in Example 4 to obtain a water-soluble granule containing 10% of nitenpyram.

[0016]

[Test Example] Examples 1 to 5 and Comparative Examples 1 to 1 shown above
The water-soluble granule prepared in 2 was left in a constant temperature bath at 40 ° C. for 3 months, the content of nitenpyram was measured by high performance liquid chromatography, and the residual rate was calculated by the following formula. Nitenpyram residual rate (%) = (content / initial content) x 1
The results are shown in [Table 1].

[0017]

[Table 1] [Table 1] shows that the residual rate of nitempyram in the water-soluble granules obtained in the present invention is obviously higher than that of the conventional water-soluble granules containing nitempyram. From this, it is understood that nitenpyram is stabilized in the water-soluble granule of the present invention.

[0018]

INDUSTRIAL APPLICABILITY The water-soluble granules of the present invention can improve the storage stability of water-soluble agrochemical active ingredients such as nitenpyram without impairing their easy solubility in water.

Claims (5)

[Claims] 1. A water-soluble granule containing a water-soluble pesticide active ingredient and a cyclodextrin compound. 2. The water-soluble granule according to claim 1, which further contains a water-soluble weakly basic substance. 3. The water-soluble granule according to claim 1, wherein the water-soluble pesticide active ingredient is a water-soluble pesticide active ingredient having a solubility in water at 20 ° C. of 0.01 g / ml or more. 4. The water-soluble granule according to claim 1 or 2, wherein the water-soluble pesticide active ingredient is nitempyram. 5. A water-soluble pesticide active ingredient in an amount of about 5 to 95% by weight and a cyclodextrin compound in an amount of about 1 to 94% by weight based on the total amount of the water-soluble granules.
The water-soluble granules described.