DESC:FIELD OF THE INVENTION

The present invention relates to a stable synergistic agrochemical composition comprising guanidine derivative and organophosphate compound. More particularly, the present invention relates to a stable synergistic agrochemical composition comprising dinotefuran and acephate as active ingredients and a process thereof for making said composition.

BACKGROUND OF THE INVENTION

Dinotefuran is a guanidine derivative developed by a Japanese Company Mitsui Chemicals having the following structure:


Dinotefuran belongs to the neo-nicotinoid class of pesticides and serves as an effective pesticide in controlling insect pests such as aphids, whiteflies, thrips, leafhopper, beetles or the like.

Acephate is an organophosphate pesticide. It is commonly used on agricultural crops for foliar, seed and soil treatments and works by damaging the nervous system of insects.

It has been found that guanidine derivatives are capable of controlling pests of agriculture crops, for example, paddy rice pests of rice stem borer, rice water weevil, planthoppers or the like.

Furthermore, it has been observed that a guanidine derivative when used in conjunction with an organophosphate agrochemical active ingredient produces an improved effect against wide range of pests.
However, the mixed preparation of a guanidine derivative and an organophosphate agrochemical active ingredient is very unstable as the decomposition rate of both the active ingredients is extremely fast. As a result, it becomes difficult to store said agrochemical composition of guanidine derivative and organophosphate compound for longer duration. Due to increased rate of decomposition of the active ingredients, said agrochemical composition of guanidine derivative and organophosphate compound shows unsatisfactory pesticidal activities. Hence, the need arises to prepare a stable agrochemical composition that has a low decomposition rate and which can be stored for longer duration.

One such stable agrochemical composition is of clothianidin (a guanidine derivative) and acephate, stabilized by compound polyoxyethylene-polyoxypropylene copolymer.

Clothianidin is an insecticide developed by Takeda Chemical Industries and Bayer AG. According to the Environmental Protection Agency (EPA), clothianidin's major risk concern is to non-target insects (honey bees). Information from standard tests and field studies, as well as incident reports involving other neonicotinoid insecticides (e.g., imidacloprid) suggest the potential for long term toxic risk to honey bees and other beneficial insects.

It is therefore desired that a stable synergistic agrochemical composition comprising guanidine derivative and organophosphate active ingredients be provided that shows low decomposition rate, is less toxic and is efficient against wide variety of pests.

OBJECTS OF THE INVENTION

The primary object and advantage of the invention is to provide a stable synergistic agrochemical composition for management of pests comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer wherein the weight percentage of guanidine derivative is 1 to 5% the weight percentage of organophosphate compound is 12 to 60% and the weight percentage of the stabilizing polymer is 1 to 10%

Another object and advantage of the invention is to provide a stable synergistic agrochemical composition for management of pests comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer wherein the weight percentage of guanidine derivative is 2 to 4% the weight percentage of organophosphate compound is 24 to 50% and the weight percentage of the stabilizing polymer is 1 to 5%

Another object and advantage of the invention is to provide a stable synergistic agrochemical composition that exhibits synergistic and improved effect over other combinations of guanidine derivative and organophosphate compound.

Another object and advantage of the invention is to provide a stable synergistic agrochemical composition that has a low rate of decomposition and can be stored for longer duration.

Another object and advantage of the invention is to provide a stable synergistic agrochemical composition, which shows broad insecticidal spectrum by acting against wide variety of pests and crop damaging insects.

Another object and advantage of the invention is to provide a stable synergistic agrochemical composition, which is low in toxicity on ecosystem besides showing outstanding pesticidal activities.

Yet another object and advantage of the invention is to provide a stable synergistic agrochemical composition which is cost-effective and has economic significance over other combinations comprising guanidine derivative and organophosphate compound

Another object and advantage of the invention is to provide a method for stabilization of the stable synergistic agrochemical composition by using stabilizing polymers including but not limited to block co-polymers

Another object and advantage of the invention is to provide a method for preparation of the stable synergistic agrochemical composition comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer.

A further object of the invention is to provide a stable synergistic agrochemical composition which meets the environmental and economic requirements imposed on modern-day insecticides/herbicides which are continually increasing, with regard, for example, to the spectrum of action, toxicity, selectivity, application rate, formation of residues, and favourable preparation ability.

Yet another object of the invention is to provide an economical, environmentally safe composition which is effective against a broad spectrum of pests.

SUMMARY OF THE INVENTION

In one aspect of the present invention, there is provided a stable synergistic agrochemical composition for management of pests comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer, wherein the weight percentage of guanidine derivative is 1 to 5% the weight percentage of organophosphate compound is 12 to 60% and the weight percentage of the stabilizing polymer is 1 to 10%

Further, there is provided a stable synergistic agrochemical composition for management of pests comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer, wherein the weight percentage of guanidine derivative is 2 to 4%, the weight percentage of organophosphate compound is 24 to 50 % and the weight percentage of the stabilizing polymer is 1 to 5%

According to another aspect of the present invention, there is provided a method for stable preparation of the synergistic agrochemical composition by stabilizing polymer compounds having polyoxyethylene group selected from but not limited to polyethylene glycol, polyoxyethylene polyoxypropylene block co-polymer, polyoxyethylene alkyl ether, polyoxyethylene aryl ether

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides a stable synergistic agrochemical composition comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer.

The guanidine derivative is selected from compounds such as, not being limited to, imidacloprid, dinotefuran.

Preferably, the guanidine derivative is dinotefuran.

The content of guanidine derivative in the stable synergistic agrochemical composition of the present invention is 1 to 5% by weight of the composition. The content of guanidine derivative is preferably 2 to 4% by weight of the composition.

The oragnophosphorous compound is selected from such as, not being limited to, acephate, chlorpyrifos, demeton-S-methyl, dichlorvos, dimethoate, ethion, fenitrothion fenthion, malathion, monocrotophos, oxydemeton-methyl, parathion, parathion-methyl, phenthoate, phorate, profenofos, quinalphos, triazophos.

Preferably, the organophosphate compound is acephate.

The content of organophosphate compound in the stable synergistic agrochemical composition of the present invention is 1 to 5% by weight of the composition. The content of organophosphate compound is preferably 2 to 4% by weight of the composition.

It has been found that the stable synergistic agrochemical composition of the present invention gets stabilized by polymer compounds having polyoxyethylene group in their structure.

The compound having polyoxyethylene group in their structure is selected from such as, not being limited to, polyethylene glycol, polyoxyethylene polyoxypropylene block co-polymer, polyoxyethylene alkyl ether, polyoxyethylene aryl ether.

Preferably, the polyoxyethylene compound is polyoxyethylene polyoxypropylene block co-polymer.

The content of polymer compounds having polyoxyethylene group in their structure in the stable synergistic agrochemical composition of the present invention is 1 to 10% by weight of the composition. The content of polymer compounds having polyoxyethylene group in their structure is preferably 1 to 5 % by weight of the composition.

The stable synergistic agrochemical composition of the present invention may further contain conventional agriculturally acceptable composition additives such as, not being limited to, spreader, wetter, dispersant, binder, disintegrant, carrier.

Suitable spreaders are, for example, sugar esters (such as sorbitan monolaurate, polyoxyethylene sorbitan monolaurate), polyoxyethylene alkyl ethers (such as polyoxyethylene lauryl ether or polyoxyethylene coconut fatty alcohol ether), polyoxyethylene aryl ethers (such as polyoxyethylene nonylphenyl ether or polyoxyethylene tristyrylphenyl ether), polyoxyethylene fatty acid esters (such as polyoxyethylene monolaurate or polyoxyethylene distearate), polyoxyethylene alkyl amines (such as polyoxyethylene stearyl fatty amine), dialkyl sulfosuccinates (such as sodium dioctyl sulfosuccinate) and alkylbenzenesulfonates (such as sodium dodecylbenzenesulfonate).

Suitable wetters are, for example, alkyl sulfates (such as sodium lauryl sulfate), polyoxyethylene alkyl ether sulfates (such as sodium polyoxyethylene lauryl ether sulfate), polyoxyethylene aryl ether sulfates (such as sodium polyoxyethylene nonylphenyl ether sulfate or ammonium polyoxyethylene tristyrylphenyl ether sulfate), alkane sulfonates (such as sodium dodecyl sulfonate), ‘alpha’-olefin sulfonates, aryl sulfonates (such as sodium dodecylbenzene sulfonate, sodium alkylnaphthalene sulfonate, sodium ‘beta’-naphthalene sulfonate formaldehyde condensate or sodium alkyl diphenyl ether sulfonate), alkylsulfosuccinates (such as sodium dioctylsulfosuccinate), lignosulfonates and polyoxyethylene aryl ether phosphates (such as polyoxyethylene phenyl ether phosphate).

Suitable dispersants are, for example, alkyl sulfates (such as sodium lauryl sulfate), polyoxyethylene alkyl ether sulfates (such as sodium polyoxyethylene lauryl ether sulfate), polyoxyethylene aryl ether sulfates (such as sodium polyoxyethylene nonylphenyl ether sulfate or ammonium polyoxyethylene tristyrylphenyl ether sulfate), alkane sulfonates (such as sodium dodecyl sulfonate), ‘alpha’-olefin sulfonates, aryl sulfonates (such as sodium dodecylbenzene sulfonate, sodium alkylnaphthalene sulfonate, sodium ‘beta’-naphthalene sulfonate formaldehyde condensate or sodium alkyl diphenyl ether susulfonate), lignosulfonates, polyoxyethylene aryl ether phosphates (such as polyoxyethylene phenyl ether phosphate) and carboxymethyl celluloses (such as sodium carboxymethyl cellulose).

Suitable binders are, for example, polyvinyl alcohol, dextrin, denatured dextrin, soluble starch, carboxymethyl cellulose and bentonite.

Suitable disintegrants are, for example, sodium tripolyphosphate, sodium hexametaphosphate, carboxymethyl cellulose and bentonite.

Suitable carriers are, for example, inorganic salts (such as sodium carbonate, sodium sulfate, sodium chloride, ammonium sulfate) and organic materials (such as lactose, urea), talc, kaolinite, pyrophyllite, montmorillonite, attapulgite, bentonite, calcite, diatomaceous earth, synthetic minerals (such as precipitated silica, fumed silica and calcium carbonate).

It has been found that the stable synergistic agrochemical composition of the present invention can have different formulations such as, not being limited to, soluble powder, soluble granule, emulsifiable concentrate, wettable powder, water dispersible granule.

It has been further found that the stable agrochemical composition of the present invention exhibits synergistic effect when compared with the effect of agrochemical composition known in the prior art.

According to another aspect of the present invention, a method for stable preparation of the synergistic agrochemical composition by use of polymers having polyoxyethylene group in their structures is provided.

In one embodiment of the present invention, a method for preparing the soluble powder and wettable powder formulations of the stable synergistic agrochemical composition is provided, the method comprising the steps of:

(a) mixing the guanidine derivative, organophosphate compounds, , stabilizing agents and agriculturally acceptable formulation additives in an appropriate ratio;
(b) pulverizing the resulting mixture by an air jet mill; and
(c) mixing the pulverized mixture by blender uniformly.

In yet another embodiment of the present invention, a method for preparing the soluble granule and water dispersible granule formulations of the stable synergistic agrochemical composition is provided, the method comprising the steps of:

(a) mixing the guanidine derivative, organophosphate compounds, stabilizing agents and agriculturally acceptable formulation additives in an appropriate ratio;
(b) pulverizing the resulting mixture by an air jet mill;
(c) mixing the pulverized mixture by blender uniformly;
(d) Kneading the resulting mixture with water and extruding through a screen of 0.3 – 1.2 mm diameter opening; and
(e) drying of the extruded material.

In order to more clearly describe the nature of the present invention, specific examples will hereinafter be described. It should be understood, however, that this is done solely by way of example, and is intended neither to delineate the scope of the invention nor limit the ambit of claims.

Example 1:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
Genapol PF-40 4.0
PG-100 3.0
Ammonium sulfate 35.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, Genapol PF-40 (a stabilizer, polyoxyethylene polyoxypropylene block copolymer produced by Clariant International Ltd.), PG-100 (a binder, modified soluble starch produced by Indian Chemicals Corporation) and ammonium sulfate (carrier) are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

Example 2:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
Genapol PF-80 4.0
PG-100 3.0
Ammonium sulfate 35.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, Genapol PF-80 (a stabilizer, polyoxyethylene polyoxypropylene block copolymer produced by Clariant International Ltd.), PG-100 and ammonium sulfate are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

Example 3:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
Genapol PF-40 2.0
Genapol PF-80 2.0
PG-100 3.0
Ammonium sulfate 35.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, Genapol PF-40, Genapol PF-80, PG-100 and ammonium sulfate are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

Example 4:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
K-SIL-20 4.0
Genapol PF-80 4.0
PG-100 3.0
Ammonium sulfate 31.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical and K-SIL-20 (precipitated silica produced by Kinetic Chemicals) are mixed in a blender and pulvernized by an air jet mill. The resulted mixture is mixed with Genapol PF-80, PG-100 and ammonium sulfate in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

Example 5:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
NPE-30 4.0
PG-100 3.0
Ammonium sulfate 35.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, NPE-30 (Nonylphenyl ethoxylate produced by Matangi Industries), PG-100 and ammonium sulfate are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

Example 6:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
Magacol 1000 4.0
PG-100 3.0
Ammonium sulfate 35.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, Magacol 1000 (PEG 1000 produced by Matangi Industries), PG-100 (a binder, modified soluble starch produced by Indian Chemicals Corporation) and ammonium sulfate (carrier) are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

Example 7:
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
Genapol T-800 4.0
PG-100 3.0
Ammonium sulfate 35.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, Genapol T-800 (fatty alcohol polyglycol ether produced by Clariant International Ltd.), PG-100 (a binder, modified soluble starch produced by Indian Chemicals Corporation) and ammonium sulfate (carrier) are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

The following comparative example shows the improvement of the present invention when the composition of Dinotefuran and Acephate is used with and without polyoxyethylene polyoxypropylene block copolymer.

Comparative Example 1
Composition:
Acephate technical (96.1%) 53.0 % by weight
Dinotefuran technical (99.5%) 4.2
PG-100 3.0
Ammonium sulfate 39.8 (remainder)

The above-mentioned Acephate technical, Dinotefuran technical, PG-100 and ammonium sulfate (carrier) are mixed in a blender, pulverized by an air jet mill and mixed in a blender uniformly. The resulting mixture is kneaded with 4% of water by weight, extruded through a screen (0.8 mm diameter opening) and dried.

TEST EXAMPLE

Each of the samples obtained in Examples 1 to7 and Comparative Example 1 was put in a 50-ml glass bottle and stored for 2 weeks in a 54°C incubator. The content of acephate and dinotefuran in the composition before and after storage was measured using HPLC, and the decomposition rate was obtained from the following equation:

The results of the above examples have been shown in Table 1 provided below:

Table 1
Example Decomposition rate
of acephate (%) Decomposition rate of dinotefuran (%)
Example 1 1.54% 0.95%
Example 2 0.00% 2.21%
Example 3 0.51% 0.50%
Example 4 2.26% 3.96%
Example 5 0.98% 2.84%
Example 6 3.51% 2.70%
Example 7 2.67% 6.27%
Comparative Example 1 12.86% 12.32%

From the foregoing description, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein.

Accordingly, it is not intended that the scope of the foregoing description be limited to the description set forth above, but rather that such description be construed as encompassing all of the features that reside in the present invention, including all the features and embodiments that would be treated as equivalents thereof by those skilled in the relevant art.
,CLAIMS:WE CLAIM:

1. A stable synergistic agrochemical composition for management of pests comprising a guanidine derivative, an organophosphate compound and a stabilizing polymer, wherein the weight percentage of guanidine derivative is 1 to 5 % the weight percentage of organophosphate compound is 12 to 60% and the weight percentage of the stabilizing polymer is 1 to 10%.

2. The stable synergistic agrochemical composition as claimed in claim 1, wherein the guanidine derivative is selected from imidacloprid and dinotefuran.

3. The stable synergistic agrochemical composition as claimed in claim 1, wherein the guanidine derivative is dinotefuran.

4. The stable synergistic agrochemical composition as claimed in claim 1, wherein the organophosphate compound is selected from acephate, Chlorpyrifos, Demeton-S-methyl, Dichlorvos, Dimethoate, Ethion, Fenitrothion, Fenthion, Malathion, Monocrotophos, Oxydemeton-methyl, Parathion, Parathion-methyl, Phenthoate, Phorate, Profenofos, Quinalphos ,Triazophos.

5. The stable synergistic agrochemical composition as claimed in claim 1, wherein the organophosphate compound is acephate.

6. The stable synergistic agrochemical composition as claimed in claim 1, wherein the stabilizing polymer is selected from polyethylene glycol, polyoxyethylene polyoxypropylene block co-polymer, polyoxyethylene alkyl ether, polyoxyethylene aryl ether.

7. The stable synergistic agrochemical composition as claimed in claim 1, wherein the stabilizing polymer is polyoxyethylene polyoxypropylene block co-polymer.

8. A stable synergistic agrochemical composition for management of pests comprising guanidine derivative, organophosphate compound and stabilizing polymer wherein the weight percentage of guanidine derivative is 2 to 4%, the weight percentage of organophosphate compound is 24 to 50% and the weight percentage of stabilizing polymer is 1 to 5%.

9. A method for preparation of the stable synergistic agrochemical composition as claimed in claim 1 comprising the steps of:
(a) mixing the guanidine derivative, organophosphate compounds, stabilizing polymer and agriculturally acceptable formulation additives in an appropriate ratio
(b) pulverizing the resulting mixture by an air jet mill; and
(c) mixing the pulverized mixture by blender uniformly.

10. A method for preparation of the stable synergistic agrochemical composition as claimed in claim 1 comprising the steps of:

(a) mixing the guanidine derivative, organophosphate compounds, stabilizing polymer and agriculturally acceptable formulation additives in an appropriate ratio
(b) pulverizing the resulting mixture by an air jet mill;
(c) mixing the pulverized mixture by blender uniformly;
(d) kneading the resulting mixture with water and extruding through a screen of 0.3 – 1.2 mm diameter opening; and
(e) drying of the extruded material.