FIELD OF THE INVENTION
[0001] The present invention relates to herbicidal formulations. Specifically, the present invention relates to a herbicidal formulations comprising Pendimethalin, and herbicidal compositions comprising combination of Pendimethalin and Oxyfluorfen that can find utility in control of annual and perennial type of weeds such as grassy, sedges and broad leaf weeds. The present invention further relates to a method for preparing the CS formulation comprising Pendimethalin and ZE formulation comprising pendimethalin and oxyfluorfen.
BACKGROUND OF THE INVENTION
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] The protection of crops from weeds and other vegetation that inhibit crop growth is a significant challenge in agriculture. To help combat this challenge, researchers in the field of synthetic chemistry have produced an extensive variety of chemicals and chemical formulations effective in the control of such unwanted growth. Chemical herbicides of many types have been disclosed in the literature and large numbers of herbicides are in commercial use.
[0004] In some cases, herbicidal active ingredients have been shown to be more effective in combination than when applied individually and this is referred to as "synergism." As described in the Herbicide Handbook of the Weed Science Society of America, Eighth Edition, 2002, p. 462, "’synergism’ is an interaction of two or more factors such that the effect when combined is greater than the predicted effect based on the response to each factor applied separately."
[0005] The search for compounds which in combination exhibit excellent herbicidal activity towards target weeds and low toxicity towards non-target plants is a continuing one because of factors such as the desire for compounds exhibiting greater activity, better selectivity, lower undesirable environmental impact, lack of phytotoxicity to the locus of application, lower production and market cost and higher effectiveness against weeds resistant to known herbicides.
[0006] The herbicidal compounds forming the synergistic composition of this invention are independently known in the art for their effects on plant growth. Pendimethalin is the common name for N-(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine. It is a dinitroaniline herbicide which is absorbed by roots and leaves and inhibits microtubule assembly. The individual formulation of Pendimethalin in various forms could be used for the control of most annual and perennial grass weeds and many annual and perennial broadleaf weeds. Oxyfluorfen is the common name for 2-chloro-l-(3-ethoxy-4-nitrophenoxy)-4-trifluoromethyl) benzene. Oxyfluorfen is a diphenyl ether herbicide and is absorbed by shoots rather than by roots with very little translocation.
[0007] The individual formulations of Oxyfluorfen in various forms find utility for control of a wide range of economically important broadleaf and grass weeds in perennial tree and vine crops, sunflower and vegetables.
[0008] Hitherto, the combination formulation of pendimethalin and oxyfluorfen has been attempted only in emulsifiable concentrate form, where direct contact between pendimethalin and oxyfluorfen has exhibited significant phytotoxicity on various crops. Furthermore, pendimethalin exhibits obnoxious staining of yellow color on the user and user equipments which are difficult to wash down.
[0009] There is, therefore, a need to develop formulations containing pendimethalin that substantially reduce the incidence of staining and that can overcome other deficiencies associated with the known arts.

OBJECTS OF THE INVENTION
[0010] An object of the present invention is to provide a formulation containing pendimethalin and a formulation containing combination of pendimethalin and oxyfluorfen that satisfies the existing needs, as well as others, and generally overcomes the deficiencies found in the prior art.
[0011] Another object of the present invention is to provide a formulation containing pendimethalin and a formulation containing combination of pendimethalin and oxyfluorfen that is user-friendly.
[0012] Another object of the present invention is to provide a formulation containing a pendimethalin and a formulation containing combination of pendimethalin and oxyfluorfen that does not exhibit substantial staining of yellow color on user(s) and equipments used by the user(s).
[0013] Another object of the present invention is to provide a formulation containing a pendimethalin and a formulation containing combination of pendimethalin and oxyfluorfen that is economically viable to produce.
[0014] Another object of the present invention is to provide a formulation containing a pendimethalin and a formulation containing combination of pendimethalin and oxyfluorfen that does not result in phytotoxicity on applied crop and is safe to use.
[0015] Another object of the present invention is to provide a formulation containing a pendimethalin and a formulation containing combination of pendimethalin and oxyfluorfen that effectively control annual and perennial type of weeds such as grassy, sedges and broad leaf weeds

SUMMARY OF THE INVENTION
[0016] The present invention relates to herbicidal formulations. Specifically, the present invention relates to a herbicidal formulation containing pendimethalin and a formulation containing combination of Pendimethalin and Oxyfluorfen that can find utility in control of annual and perennial type of weeds such as grassy, sedges and broad leaf weeds.
[0017] In one aspect, the present invention relates to a herbicidal CS formulation comprising pendimethalin and at least one agriculturally acceptable adjuvant.
[0018] In one aspect, the present invention relates to a herbicidal ZE formulation (combination of capsule suspension and suspoemulsion) comprising pendimethalin, oxyfluorfen and at least one agriculturally acceptable adjuvant.
[0019] In another aspect, the present invention relates to a herbicidal ZE formulation of pendimethalin and oxyfluorfen, wherein the pendimethalin is present in an amount of 20-40 % by weight of the formulation.
[0020] In another aspect, the present invention relates to a herbicidal ZE formulation of pendimethalin and oxyfluorfen, wherein oxyfluorfen is present in an amount of 2-7 % by weight of the formulation.
[0021] In another aspect, the present invention relates to a herbicidal ZE formulation of pendimethalin and oxyfluorfen and herbicidal CS formulation of pendimethalin, wherein pendimethalin is in capsule suspension form.
[0022] In another aspect, the present invention relates to a herbicidal ZE formulation of pendimethalin and oxyfluorfen, wherein oxyfluorfen is in suspo-emulsion form.
[0023] In another aspect, the present invention relates to herbicidal ZE formulation of pendimethalin and oxyfluorfen and herbicidal CS formulation of pendimethalin, wherein the pendimethalin is encapsulated in polymeric wall.
[0024] In another aspect, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen and herbicidal CS formulation of pendimethalin, wherein the polymeric wall comprises one or more polymers selected from polyamide and amphiphilic polymer.
[0025] In another aspect, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen and herbicidal CS formulation of pendimethalin, wherein the amphiphilic polymer is polyethylene glycol (PEG)-hydroxydimethyl phthalate.
[0026] In an embodiment, the pendimethalin is encapsulated in a polymeric wall.
[0027] In yet another aspect, the present invention relates to a method of preparation of a herbicidal CS formulation comprising pendimethalin and ZE formulation comprising pendimethalin and oxyfluorfen.
[0028] Accordingly, in an embodiment, the present invention relates to a method of preparation of a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the method comprises the steps:
(i) encapsulating pendimethalin in a polymeric wall;
(ii) preparing a suspension of the encapsulated pendimethalin;
(iii) preparing emulsion of oxyfluorfen; and
(iv) adding the emulsion of oxyfluorfen obtained in step (iii) to the encapsulated suspension of pendimethalin obtained in step (ii) to form the ZE formulation.
[0029] In an embodiment, the present invention relates to a method of preparation of a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing organic warm solution comprising pendimethalin and a wall forming material;
(iii) dispersing the warm solution obtained in step (ii) in the aqueous solution obtained in step (i) under stirring as a homogenous suspension to obtain encapsulated suspension of pendimethalin;
(iv) preparing oxyfluorfen solution with surfactant or emulsifier; and
(v) mixing oxyfluorfen solution obtained in step (iv) with the encapsulated suspension of pendimethalin obtained in step (iii) under stirring to obtain the ZE formulation.
[0030] In another embodiment, the present invention relates to a method of preparation of a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing organic warm solution comprising pendimethalin and first wall forming material;
(iii) dispersing the warm solution obtained in step (ii) to the aqueous solution obtained in step (i) under stirring to obtain homogenous suspension;
(iv) adding second wall forming material to obtain encapsulated suspension of pendimethalin;
(v) preparing oxyfluorfen solution with surfactant or emulsifier; and
(vi) mixing oxyfluorfen solution obtained in step (iv) with the encapsulated suspension of pendimethalin obtained in step (iii) under stirring to obtain the ZE formulation.
[0031] In an embodiment, the aqueous solution comprising at least one monomer, at least one surfactant or dispersant is prepared in the temperature range of 50 °C to 90 °C.
[0032] In an embodiment, the organic warm solution comprising pendimethalin and a wall forming material is in the temperature range of 70 °C to 90 °C.
[0033] In an embodiment, the wall forming material comprising polyisocyanates selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethene-4,4'-diisocyanate, polymethylene polyphenylene isocyanate, 2,4,4'-diphenyl ether triisocyanate, 3,3'-dimethyl-4,4'-diphenyl diisocyanate, 3,3'-dimethoxy-4,4'-diphenyl diisocyanate, 1,5-naphthylene diisocyanate, 4,4'4?-triphenylmethane triisocyanate, toluene diisocyanate, methylene diphenyl isocyanate, polymethylene and polyphenylisocyanate or combination thereof; diamines selected from the group consisting of ethylenediamine, propylene-1,3-diamine, tetramethylenediamine, pentamethylenediamine, 1,6-hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 4,9-dioxadodecane-1,12-diamine, 1,3-phenylenediamine, 2,4-toluenediamine, 2,6-toluenediamine and 4,4'-diaminodiphenylmethane or combination thereof; polyamine; polyamide; polyethylene glycol, polyacid chloride; polychloroformate; or polysulfonyl chloride.
[0034] In another aspect, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the herbicidal ZE formulation is applied to herbs by using ground water mixing, spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping or irrigation methods.
[0035] In an embodiment, the herbicidal ZE formulation of the present invention can control the weeds which occur in crop plants, ornamentals plants, agriculture plants, horticulture and forests.
[0036] In another aspect, the present invention relates to a method for controlling weeds using the herbicidal ZE formulation comprising pendimethalin and oxyfluorfen.
[0037] In an embodiment, the present invention relates to a method for controlling weeds at a locus which comprises applying to the locus herbicidally effective amount of ZE formulation comprising pendimethalin and oxyfluorfen.
[0038] In yet another aspect, the present invention relates to a multi-pack herbicidal product for controlling weeds at a locus comprising:
(a) an ZE formulation comprising pendimethalin and oxyfluorfen; and
(b) an instruction manual consisting of instructions for administering the ZE formulation.
[0039] In another aspect, the present invention relates to a herbicidal CS formulation comprising pendimethalin and at least an agriculturally acceptable adjuvant.
[0040] In an embodiment, the present invention relates to a method of preparation of a herbicidal CS formulation comprising pendimethalin, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing organic warm solution comprising pendimethalin and a wall forming material; and
(iii) dispersing the warm solution obtained in step (ii) in the aqueous solution obtained in step (i) under stirring as a homogenous suspension to obtain CS formulation of pendimethalin
[0041] In an embodiment, the present invention relates to a method for controlling weeds using the herbicidal CS formulation comprising pendimethalin.
[0042] Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments

DETAILED DESCRIPTION
[0043] The following is a detailed description of embodiments of the disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0044] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0045] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.
[0046] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0047] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0048] Unless the context requires otherwise, throughout the specification which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense that is as “including, but not limited to.”
[0049] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[0050] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written
[0051] The description that follows, and the embodiments described therein, is provided by way of illustration of an example, or examples, of particular embodiments of the principles and aspects of the present disclosure. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the disclosure.
[0052] It should also be appreciated that the present disclosure can be implemented in numerous ways, including as a system, a method or a device. In this specification, these implementations, or any other form that the invention may take, may be referred to as processes. In general, the order of the steps of the disclosed processes may be altered within the scope of the invention.
[0053] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.
[0054] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.
[0055] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing..
[0056] The term, “ZE formulation” as used herein refers to stable mixed formulation of capsule suspension formulation (CS formulation) and suspo-emulsion formulation (SE). The formulation must consist of an emulsion of fine droplets of capsulated pendimethalin technical material and a suspension of fine particles of oxyfluorfen technical material in an aqueous phase, together with suitable formulants. After gentle agitation the material must appear homogeneous and be suitable for dilution in water.
[0057] The term, “agriculturally acceptable adjuvant” as used herein refers to any agriculturally acceptable inactive substance or mixture added to a formulation of a herbicidal active ingredient and/or used in tank-mix with a herbicidal active ingredient. Examples of agriculturally acceptable adjuvant include, but not limited to surfactants, dispersants, antifreeze agents, clays, water, salts, polymers, emulsifying agents, suspension stabilizing agents and density balancing agents.
[0058] The term, “surfactants” as used herein refers to agriculturally acceptable surfactant. Examples include, but not limited to ethoxylated lignosulfonic acid salts, lignosulfonic acid salts, oxidized lignins, lignin salts, salts of styrene-maleic anhydride copolymers, polyvinyl alcohol, salts of partial esters of styrene-maleic anhydride copolymers, partial salts of polyacrylic acid and partial salts of polyacrylic acid terpolymers.
[0059] The term, “emulsifier”, as used herein refers to agriculturally acceptable emulsifiers and can be of the anionic, cationic or non-ionic type. The emulsifiers can be selected from a group consisting of ethoxylated and ethopropoxylated alcohols and nonyl phenols, ethoxylated tristeryl phenol, sodium lauryl sulphate, lignosulfonate, ethoxylated tristeryl phenol phosphates, ethoxylated and ethopropoxylated castor oil, calcium alkyl benzene sulfonates, proprietary blended emulsifiers or polymeric surfactants and the like as known to a person skilled in the art.
[0060] The term, “weed” as used herein refers to unwanted plant harmful to plant of interest.
[0061] The term, “herbicidally effective amount”, as used herein refers to the quantity of herbicidal active agent, applied in an amount which will provide the required control of weed on commercial crops. The particular amount is dependent upon many factors including, for example, type of formulations, the crop, weed sought to be controlled and environmental conditions.
[0062] The term, “control” or “controlling”, as used herein refers to preventing, reducing, killing, inhibiting the growth of, inhibiting the reproduction of, and/or eliminating at least one weed i.e. an undesirable plant in a crop growing environment.
[0063] The present invention relates to herbicidal formulations. Specifically, the present disclosure relates to a herbicidal ZE formulation comprising Pendimethalin and Oxyfluorfen and at least one agriculturally acceptable adjuvant.
[0064] The present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen that can find utility in control of annual and perennial type of weeds such as grassy, sedges and broad leaf weeds.
[0065] In an embodiment, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the formulation includes an appropriate amount of pendimethalin by weight of the composition.
[0066] In an embodiment, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the formulation includes an appropriate amount of oxyfluorfen by weight of the composition.
[0067] In an embodiment, a herbicidal capsule suspension formulation of pendimethalin comprising a herbicidally effective amount of microencapsulated pendimethalin wherein the pendimethalin being encapsulated within a polymeric wall, said polymeric wall being in-situ formed by an interfacial polymerization reaction occurring between a first phase dispersed in a second phase wherein magnesium salt is present in atleast one of said phase.
[0068] In a preferred embodiment, the magnesium salt is magnesium sulphate.

[0069] In an embodiment, the herbicidal ZE formulation comprises,
(a) 10-40 % pendimethalin;
(b) 2-7 % oxyfluorfen;
(c) 28-38 % agriculturally acceptable adjuvant; and
(d) 15-60 % diluent
[0070] In an embodiment, the herbicidal ZE formulation comprises,
(a) 10-40 % pendimethalin;
(b) 2-7 % oxyfluorfen;
(c) 10-25% Inorganic salt based on magnesium sulphate
(d) 35-40 % demineralised water;
(e) 5-20 % surfactants; and
.
[0071] In an embodiment, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the formulation is capable of exhibiting synergistic herbicidal activity at much lesser amounts of pendimethalin and oxyfluorfen as compared to the amounts when used alone.
[0072] In an embodiment, the ZE and CS formulation is controlled or delayed release formulation. This treatment gives benefits to the operator, environmental safety and tank mix compatibility.
[0073] In a preferred embodiment, the herbicidal ZE and CS formulation includes pendimethalin encapsulated in a polymeric wall.
[0074] In a preferred embodiment, the herbicidal ZE formulation includes emulsion of oxyfluorfen.
[0075] In an embodiment, the present invention relates to a herbicidal ZE and CS formulation, wherein the polymeric wall is made up of a polyamide or mixture of polyamide and at least one amphiphilic polymer or combination thereof.
[0076] In a preferred embodiment, the amphiphilic polymer is polyethylene glycol (PEG). However, a person skilled in the art would appreciate that any other wall forming materials and/or polymers, as known to those of ordinary skill in the art, can be used without departing from the scope and spirit of the instant invention. Such materials can be, including but not limited to, polyurea, polyamide, mixture of polyurea and polyamide, polyurethane, mixture of urea and formaldehyde, melamine resin, nylon, gelatin and gelatine-gum arabic.
[0077] In an embodiment, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the said pendimethalin is in capsule suspension form.
[0078] In an embodiment, the present invention relates to a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen, wherein the said oxyfluorfen is in suspo-emulsion form.
[0079] In yet another aspect, the present invention relates to a method of preparation of a herbicidal ZE formulation including herbicidally effective amount of pendimethalin and oxyfluorfen, wherein the method comprises the steps:
(i) encapsulating pendimethalin in a polymeric wall;
(ii) preparing a suspension including said encapsulated pendimethalin; and
(iii) adding emulsion of oxyfluorfen to said capsule suspension of pendimethalin to form the ZE formulation.
[0080] In an embodiment, the present invention relates to a process for preparation of herbicidal ZE formulation pendimethalin and oxyfluorfen, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one polymer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing warm solution comprising pendimethalin and a wall forming material;
(iii) dispersing the warm solution obtained in step (ii) in the aqueous solution obtained in step (i) under stirring as a homogenous suspension to obtain encapsulated suspension of pendimethalin;
(iv) preparing oxyfluorfen solution with surfactant or emulsifier; and
(v) mixing oxyfluorfen solution obtained in step (iv) with the encapsulated suspension of pendimethalin obtained in step (iii) under stirring to obtain the ZE formulation.
[0081] In an embodiment, the pendimethalin in the ZE and CS formulation is surrounded by a barrier or membrane or polymeric or similar material.
[0082] In an embodiment, the polymeric wall in the ZE and CS formulation is formed using interfacial polymerization by contacting a second wall forming material added to an aqueous solution with a first wall forming material present within an organic phase.
[0083] In an embodiment, the interfacial polymerization between the wall forming materials can be carried out at ambient temperature or at an elevated temperature.
[0084] In an embodiment, the temperature for the interfacial polymerization reaction is between 5 °C and 90 °C, preferably between 10 °C and 70 °C and more preferably between 15 °C and 60 °C.
[0085] In an embodiment, the temperature for the interfacial polymerization reaction is in the range of 30 °C to 90 °C.
[0086] In another embodiment, the wall forming materials are allowed to react with each other for maintaining the emulsion for a sufficient period of time to allow substantial completion of the polymerization reaction between the wall forming materials.
[0087] In an embodiment, homogenous dispersion of polymer microencapsulated pendimethalin in water with an effective emulsifier, such as lignosulfonate, may be blended with a suspension system. The suspension system composition may include a combination of agents, such as surfactants, dispersants, antifreeze agents, clays, water, salts, polymers, and other suspension stabilizing and density balancing agents, appropriately selected to keep the microcapsules in stable homogeneous suspension in the water-based carrier over an extended period of time as long as for example two years or more.
[0088] In an embodiment, the first wall forming material is preferably selected from a polyisocyanate, a polyacid chloride, a polychloroformate and a polysulfonyl chloride. The second wall forming component is preferably selected from diamine, polyamine and/or polyol. However, any other polymeric material, as known to or appreciated by a person skilled in the art, can be used for preparation of first and/or second polymeric wall without departing from the scope and spirit of the present invention.
[0089] In an embodiment, the polyisocyanates can be selected from tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethylene-4,4'-diisocyanate, methylene diphenyl isocyanate, polymethylene polyphenylene isocyanate, 2,4,4'-diphenyl ether triisocyanate, 3,3'-dimethyl-4,4'-diphenyl diisocyanate, 3,3'-dimethoxy-4,4'-diphenyl diisocyanate, 1,5-naphthylene diisocyanate, and 4,4'4?-triphenylmethane triisocyanate or combination thereof.
[0090] In an embodiment, the diamines can be selected from ethylenediamine, propylene-1,3-diamine, tetramethylenediamine, pentamethylenediamine, 1,6-hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 4,9-dioxadodecane-1,12-diamine, 1,3-phenylenediamine, 2,4- and 2,6-toluenediamine and 4,4'-diaminodiphenylmethane or combination thereof.
[0091] In an embodiment, the diamines can be an acid addition salt.
[0092] In an embodiment, the aqueous solution comprises at least one surfactant. Preferably, the surfactant may be selected from the group comprising ethoxylated lignosulfonic acid salts, lignosulfonic acid salts, oxidized lignins, lignin salts, salts of styrene-maleic anhydride copolymers, polyvinyl alcohol, salts of partial esters of styrene-maleic anhydride copolymers, partial salts of polyacrylic acid and partial salts of polyacrylic acid terpolymers.
[0093] In an embodiment, the mode of application of the herbicidal ZE and CS formulation formulation is by using at least one technique selected from the group consisting of ground water mixing, spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping, and irrigation methods.
[0094] In an embodiment, the ZE formulation according to the present disclosure may further be neutralized with a mineral acid to regulate the pH within the desired range. Accordingly, the formulations can additionally include from about 0.1% to about 10% of an acid, which may be a mineral or an organic acid.
[0095] In an embodiment, the agrochemical ZE and CS formulation can be used for controlling, i.e. containing or destroying, and suppressing weeds which occur on plants, especially in crop plants and ornamentals, in agriculture, in horticulture and in forests.
[0096] In an embodiment, the agrochemical ZE and CS formulation can be applied advantageously for weed control in crops, such as Allium cepa, Ananas comosus, Arachis hypogaea, Asparagus officinalis, Beta vulgaris ssp. altissima, Beta vulgaris ssp. rapa, Brassica napus var. napus, Brassica napus var. napobrassica, Brassica rapa var. silvestris, Camellia sinensis, Carthamus tinctorius, Carya illinoinensis, Citrus limon, Citrus sinensis, Coffea arabica (Coffea canephora, Coffea liberica), Cucumis sativus, Cynodon dactylon, Daucus carota, Elaeis guineensis, Fragaria vesca, Glycine max, Gossypium hirsutum, (Gossypium arboreum, Gossypium herbaceum, Gossypium vitifolium), Helianthus annuus, Hevea brasiliensis, Hordeum vulgare, Humulus lupulus, Ipomoea batatas, Juglans regia, Lens culinaris, Linum usitatissimum, tycopersicon lycopersicum, Malus spp., Manihot esculenta, Medicago sativa, Musa spp., Nicotiana tabacum (N.rustica), Olea europaea, Oryza sativa, Phaseolus lunatus, Phaseolus vulgaris, Picea abies, Pinus spp., Pisum sativum, Prunus avium, Prunus persica, Pyrus communis, Ribes sylvestre, Ricinus communis, Saccharum officinarum, Secale cereale, Solanum tuberosum, Sorghum bicolor (s. vulgare), Theobroma cacao, Trifolium pratense, Triticum aestivum, Triticum durum, Vicia faba, Vitis vinifera, Zea mays; in fruit, for example cantaloupes, honeydews, crenshaw melons, watermelons; in tree nuts, such as almonds, breechnuts, brazil nuts, butternuts, cashews, chestnuts, chinquapins, filberts, hickory nuts, macadamia nuts, pecans, pistachios, walnuts; in turfgrasses, such as established lawns, ornamental turfgrass, landscapes areas, commercial and residential turfgrass; in vegetables such as asparagus, cucumbers, dry beans, peppers, pumpkin, succulent snap beans, tomatoes and winter squash.
[0097] In yet another aspect, the present invention relates to a multi-pack herbicidal product for controlling weeds at a locus comprising components of the present invention and a manual.
[0098] In an embodiment, the manual in the multi-pack herbicidal product includes the instructions for administering the component of the present invention.
[0099] In an embodiment, the instruction manual in the multi-pack herbicidal product includes the instruction for administering the ZE and CS formulation at a locus, or to a foliage of the plans or to the soil or to other plant propagating organs.
[00100] In another aspect, the present invention relates to CS formulation comprising pendimethalin.
[00101] In yet another aspect, the present invention relates a method of preparing CS formulation comprising pendimethalin, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing warm solution comprising pendimethalin and a wall forming material; and
(iii) dispersing the warm solution obtained in step (ii) in the aqueous solution obtained in step (i) under stirring as a homogenous suspension to obtain CS formulation of pendimethalin.
[00102] In yet another aspect, the present invention relates a method of preparing CS formulation comprising pendimethalin, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing organic warm solution comprising pendimethalin and first wall forming material;
(iii) dispersing the warm solution obtained in step (ii) to the aqueous solution obtained in step (i) under stirring to obtain homogenous suspension; and
(iv) adding second wall forming material to obtain encapsulated suspension of pendimethalin.
[00103] While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.
EXAMPLES
[00104] The present invention is further explained in the form of following examples. However, it is to be understood that the following examples are merely illustrative and are not to be taken as limitations upon the scope of the invention.
[00105] Example 1:
Preparation of ZE formulation comprising pendimethalin and oxyfluorfen using polyamide polymeric wall
2-5 Parts by weight of craft lignin, 5-10 parts of lignosulphonate, 5-10 parts of non-ionic surfactant or acrylic polymeric dispersant, 5-20 parts by weight of magnesium salt were added to 35-50 parts by weight of demineralised water. The solution was stirred using a high shear mixer at 4000-5000 rpm and warmed to 50-70 °C. To the stirred mixture was added a warmed solution (50-70 °C) of 10-40 parts by weight of pendimethalin and 1-4 parts by weight of an isocyanate such as toluene diisocyanate, methylene diphenyl isocyanate or polymethylpolyphenyl isocyanate, under high shear mixing at 4000-5000 rpm, over a period of 2 hours to form a homogeneous suspension. Speed of mixing was reduced to 500-1000 rpm to accelerate condensation of the polyisocyanate prepolymer to form the first polymeric wall. After an hour, 5-10 parts by weight of aqueous solution of diamine such as ethylene diamine, diethylene tetra amine or hexamethylene diamine was added and the material was mixed for 1 hour to form the second polymeric wall. Finally pH was adjusted with an organic acid.
To the above encapsulated suspension of pendimethalin, 5 - 10 parts by weight of a non-ionic surfactant were added and 2-7 parts by weight of Oxyfluorfen were added and mixed for 30 minutes at an ambient temperature to form a ZE formulation of Pendimethalin and Oxyfluorfen.
[00106] Example 2:
Preparation of ZE formulation comprising pendimethalin and oxyfluorfen using amphiphilic polymeric wall based on polyethylene glycol (PEG)
Hydroxyl dimethyl isophthalate 2-5 parts, pendimethalin 10-40 parts, aromatic solvent 5-20 parts were mixed and warmed to 70-90°C and was added to mixture of polyethylene glycol 4-15 parts, craft lignin 2-5 parts, polymeric surfactant 1-5 parts, 25-30 parts dimineralised water over a period of 6-9 hrs by maintaining temperature of 50-70°C . Thereafter, the material was mixed under high shear at 4000-5000 rpm for 1 hour to attain particle size below 10 micron. To the mass was added a mixture of 2-7 parts of oxyfluorfen, 5-10 parts by weight of non-ionic emulsifier. The mass was mixed for 1 hour and pH adjusted to 4.5-6.0.

[00107] Example 3:
Preparation of ZE formulation comprising 24% pendimethalin + 4.1 % oxyfluorfen
Sr. No. Raw Material Quantity
1 Pendimethalin Tech 260.0 g
2 Oxyfluorfen Tech 43.20 g
3 PM- 200 (Diisocyanato-diphenylmethane (MDI) based composition) 11.0 g
4 Magnesium Sulphate 123.60 g
5 Water 385.0 g
6 Reax – 100M (Lignosulfonic acid, sodium salt sulfomethylated) 8.0 g
7 Polyfon – H (Lignosulfonic acid, Sodium salt) 8.0 g
8 Silicon Defoamer 2.0 g
9 Atlox 550 S
(Modified styrene acrylic polymer) 8.0 g
10 HDMA (Hexamethylene-diamine) 8.0 g
11 Xanthan Gum 1 % solution 25 mL
12 Solvent – C-IX 20.0 g
13 2090 M (Emulsifier) 5.60 g
14 2756 (Emulsifier) 0.50 g
15 HCl (1:1) 25 mL

Step-1
In a beaker containing water (385 mL), was added magnesium sulphate (123.6 g) and mixed properly. To the solution, Reax – 100M (8 g) and Polyfon –H (8 g) was added and stirred at 600 to 800 RPM.

Step-2
Silicon Defoamer (2 g) was added to the solution obtained in step-1 and the mixture was heated at the temperature in the range of 50-60 °C. To the mixture, Altox 550S (8 g) was added and the solution was stirred at 600 to 800 RPM for an hour to obtain the aqueous phase solution.
Step-3
Pendimethalin tech (260 g) and PM-200 (11 g) was mixed well in a beaker and warmed the solution in a water bath to obtain oil phase solution.
Step-4
The aqueous phase solution obtained in step-2 was taken in beaker and placed on a stirrer of 10000 RPM capacity and the aqueous phase solution was stirred at 6000 RPM to 7000 RPM. The oil phase solution obtained in step-3 was mixed slowly with aqueous phase solution for an hour under stirring. The resulting mixture was stirred for one more hour. To the mixture, HDMA solution (8 g in 40 mL of water) was added slowly under stirring for one hour and aqueous. HCl (1:1, 25 mL) was added to adjust the pH of mixture in the range of 6.5 to 7.5. The resulting mixture was stirred for 2 hours to obtain the suspension of encapsulated pendimethalin.
Step–5
Oxyfluorfen tech (43.20 g) and C-IX solvent (20 g) was taken in a beaker and stirred well to obtain oil phase solution. The oil phase solution obtained is mixed with warm water and stirred at 2000 to 3000 RPM.
Step–6
The suspension of encapsulated pendimethalin obtained in step 4 was mixed with the oxyfluorfen solution obtained in step-5 under stirring for an hour to obtain the ZE formulation.
[00108] The following comparative examples relating to CS formulation comprising 38.7 % pendimethalin were prepared by following the similar procedure as described in steps 1 to 4 of Example 3 but all the formulations have been failed as the different composition is used than as suggested in the present invention.

[00109] Comparative Example 1:
CS composition of pendimethalin
Sr. No. Raw Material Quantity
1 Pendimethalin Tech 103 g
2 Solvent C-9 37 g
3 Calcium chloride 22.5 g
4 Calcium Acetate 2.2 g
5 PVA (Polyvinyl alcohol) 2.5 g
6 954 L (EO/PO block co-polymer) 3.0 g
7 Ethylan NS-500 LQ
(Alcohol polyglycol ether) 3 g
8 1460 (Biocide) 2 g
9 Silicon Defoamer 1.2 g
10 DM water 73.6 g

Findings: Capsulation is not proper

Comparative Example 2:
[00110] CS composition of pendimethalin
Sr. No. Raw Material Quantity
1 Pendimethalin Tech 103 g
2 Solvent C-9 37 g
3 TDI (Toluene diisocyanate) 2.5 g
4 Calcium chloride 22.5 g
5 Calcium Acetate 2.2 g
6 PVA (Polyvinyl alcohol) 2.5 g
7 954 L (EO/PO block co-polymer) 3.0 g
8 Ethylan NS-500 LQ
(Alcohol polyglycol ether) 3 g
9 1460 (Biocide) 2 g
10 Defoamer 1.2 g
11 DM water 73.6 g

Findings: Capsulation was not proper and also material turned viscous after some time

Comparitive Example 3:
CS composition of pendimethalin
Sr. No. Raw Material Quantity
1 Pendimethalin Tech 38.7 g
2 Solvent C-9 10 g
3 TDI (toluene diisocyanate) 2 g
4 PVA (polyvinyl alcohiol) 0.5
5 954 L (EO/PO block co-polymer) 3.0 g
6 Ethylan NS-500 LQ
(Alcohol polyglycol ether) 3.0 g
7 1460 (Biocide) 3.0 g
8 Silicon defomer 0.1 g
9 PG (Polyethylene glycol) 4 g
10 DM water 73.6 g

Findings: Capsulation was not proper and also material turned viscous after some time

[00111] Comparitive Example 4:
CS composition of pendimethalin
Sr. No. Raw Material Quantity
1 Pendimethalin Tech 390 g
2 Solvent C-9 100 g
3 TDI (toluene diisocyanate) 10 g
4 Calcium chloride 50 g
5 Calcium Acetate 5 g
6 Polyvinyl alcohol (PVA) 5 g
7 954 L (EO/PO block co-polymer) 5 g
8 Ethylan NS-500 LQ
(Alcohol polyglycol ether) 30 g
9 1460 (Biocide) 30 g
10 Silicon defoamer 30 g
11 DM water 340 g

Findings: Capsulation was not proper and also material turned semi-solid after 1 day.

[00112] Comparitive Example 5:
CS composition of pendimethalin
Sr. No. Raw Material Quantity
1 Pendimethalin Tech 390 g
2 Solvent C-9 100 g
3 MDI (Methylene diphenyl diisocyanate) 10 g
4 Calcium Acetate 5 g
5 Polyvinyl alcohol (PVA) 5 g
6 Silicon defoamer 5 g
7 Ethylan NS-500 LQ
(Alcohol polyglycol ether) 30 g
8 1460 (Biocide) 50 g
9 DM water 340 g

Findings: Formulation was viscous and semi-solid.

[00113] From the above comparative examples, it is concluded that Calcium salts are not compatible as they tend to separate out and PVA could not form stable matrix. On the other hand, magnesium salt as used in the present invention such as Magnesium Sulphate is compatible as they not tend to separate out and also a modified styrene acrylic polymer as used in the present invention such as Altox 550 S acted as best rheology modifier.

[00114] The foregoing examples are merely illustrative and are not to be taken as limitations upon the scope of the invention. Various changes and modifications to the disclosed embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the scope of the invention.

ADVANTAGES OF THE PRESENT INVENTION
[00115] The present invention provides a ZE formulation comprising pendimethalin and oxyfluorfen that satisfies the existing needs, as well as others, and generally overcomes the deficiencies found in the prior art.
[00116] The present invention provides a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen that is user-friendly.
[00117] The present invention provides a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen that does not exhibit or exhibits substantially less obnoxious staining of yellow color on the user.
[00118] The present invention provides a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen that is economically viable to produce.
[00119] The present invention provides a herbicidal ZE formulation comprising pendimethalin and oxyfluorfen that does not result in phytotoxicity on applied crop and is safe to use.

We Claim:
1. A herbicidal ZE formulation comprising:
(a) pendimethalin;
(b) oxyfluorfen; and
(c) at least one agriculturally acceptable adjuvant.

2. The herbicidal ZE formulation as claimed in claim 1, wherein the said pendimethalin is present in an amount of 10-40 % by weight of the formulation.

3. The herbicidal ZE formulation as claimed in claim 1, wherein the said oxyfluorfen is present in an amount of 2-7 % by weight of the formulation.

4. The herbicidal ZE formulation as claimed in claim 1, wherein the formulation comprises:
(a) 10-40 % pendimethalin;
(b) 2-7 % oxyfluorfen;
(c) 35-40 % demineralised water;
(d) 10-25 % Inorganic salt based based on magnesium sulphate; and
(d) 5-20 % surfactants.

5. The herbicidal ZE formulation as claimed in claim 1, wherein the said agriculturally acceptable adjuvant is selected from the group consisting of surfactants, dispersants, antifreeze agents, clays, water, salts, polymers, emulsifiers, suspension stabilizing agents and density balancing agents.

6. The herbicidal ZE formulation as claimed in claim 5, wherein the said polymer is selected from the group consisting of polyamide, polyurea, polyurethane, melamine resin, nylon, gelatin, polyisocyanate, polyacid chloride, polychloroformate, polysulfonyl chloride, diamine, polyamine, polyol and amphiphilic polymer.

7. The herbicidal ZE formulation as claimed in claim 5, wherein the said surfactant is selected from the group consisting of ethoxylated lignosulfonic acid salts, lignosulfonic acid salts, oxidized lignins, lignin salts, salts of styrene-maleic anhydride copolymers, polyvinyl alcohol, salts of partial esters of styrene-maleic anhydride copolymers, partial salts of polyacrylic acid, partial salts of polyacrylic acid terpolymers and emulsifier.

8. The herbicidal ZE formulation as claimed in claim 5, wherein the said emulsifier is selected from the group consisting of ethoxylated and ethopropoxylated alcohols and nonyl phenols, ethoxylated tristeryl phenol, sodium lauryl sulphate, lignosulfonate, ethoxylated tristeryl phenol phosphates, ethoxylated and ethopropoxylated castor oil, calcium alkyl benzene sulfonates, proprietary blended emulsifiers

9. A process for preparation of herbicidal ZE formulation as claimed in claim 1, wherein the process comprises the steps:
(i) encapsulating pendimethalin in a polymeric wall;
(ii) preparing a suspension of the said encapsulated pendimethalin; and
(iii) adding emulsion of oxyfluorfen to the suspension of encapsulated pendimethalin to obtain the ZE formulation.

10. A process for preparation of herbicidal ZE formulation as claimed in claim 1, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing warm solution comprising pendimethalin and a wall forming material;
(iii) dispersing the warm solution obtained in step (ii) in the aqueous solution obtained in step (i) under stirring as a homogenous suspension to obtain encapsulated suspension of pendimethalin;
(iv) preparing oxyfluorfen solution with surfactant or emulsifier; and
(v) mixing oxyfluorfen solution obtained in step (iv) with the encapsulated suspension of pendimethalin obtained in step (iii) under stirring to obtain the ZE formulation.

11. A process for preparation of herbicidal ZE formulation as claimed in claim 1, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing warm solution comprising pendimethalin and first wall forming material;
(iii) dispersing the warm solution obtained in step (ii) in the aqueous solution obtained in step (i) under stirring to obtain homogenous suspension;
(iv) adding second wall forming material to obtain encapsulated suspension of pendimethalin;
(v) preparing oxyfluorfen solution with surfactant or emulsifier; and
(vi) mixing oxyfluorfen solution obtained in step (iv) with the encapsulated suspension of pendimethalin obtained in step (iii) under stirring to obtain the ZE formulation.

12. The process as claimed in any one of the claims 9 - 11, wherein the wall forming material comprising, polyisocyanates selected from the group consisting of tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethene-4,4'-diisocyanate, polymethylene polyphenylene isocyanate, 2,4,4'-diphenyl ether triisocyanate, 3,3'-dimethyl-4,4'-diphenyl diisocyanate, 3,3'-dimethoxy-4,4'-diphenyl diisocyanate, 1,5-naphthylene diisocyanate, 4,4'4?-triphenylmethane triisocyanate, toluene diisocyanate, methylene diphenyl isocyanate, polymethylene and polyphenylisocyanate or combination thereof; diamines selected from the group consisting of ethylenediamine, propylene-1,3-diamine, tetramethylenediamine, pentamethylenediamine, 1,6-hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, 4,9-dioxadodecane-1,12-diamine, 1,3-phenylenediamine, 2,4-toluenediamine, 2,6-toluenediamine and 4,4'-diaminodiphenylmethane or combination thereof; polyamine; polyamide; polyethylene glycol, polyacid chloride; polychloroformate; or polysulfonyl chloride.

13. The herbicidal ZE formulation as claimed in claim 1, wherein the ZE formulation is delayed or controlled release formulation of active ingredients.

14. The herbicidal ZE formulation as claimed in claim 1, wherein the ZE formulation is applied to herbs by using ground water mixing, spraying, rubbing, dusting, pouring, mist blowing, soil mixing, dipping or irrigation methods.

15. A method for controlling weeds at a locus which comprises applying to the locus a herbicidally effective amount of a ZE formulation as claimed in claim 1.

16. A multi-pack herbicidal product for controlling weeds at a locus comprising:
(a) a ZE formulation as claimed in claim 1; and
(b) an instruction manual consisting of instructions for administering the ZE formulation.

17. A herbicidal capsule suspension formulation of pendimethalin comprising a herbicidally effective amount of microencapsulated pendimethalin wherein the pendimethalin being encapsulated within a polymeric wall, said polymeric wall being in-situ formed by an interfacial polymerization reaction occurring between a first phase dispersed in a second phase wherein magnesium salt is present in atleast one of said phase.

18. The capsule suspension formulation as claimed in claim 1 wherein the magnesium salt is magnesium sulphate.

19. A process for preparation of herbicidal CS formulation as claimed in claim 17, wherein the process comprises the steps:
(i) preparing an aqueous solution comprising at least one monomer, at least one surfactant or dispersant and optionally heating the aqueous solution;
(ii) preparing warm solution comprising pendimethalin and a wall forming material;
(iii) dispersing the warm solution obtained in step (ii) in aqueous solution obtained in step (iv) under stirring as a homogenous suspension to obtain CS formulation of pendimethalin.
FOR Insecticides (India) Ltd

Dated: April 17, 2018