Claims:We Claim:
1. A novel formulation of Pendimethalin and Diclosulam comprising:
a) Pendimethalin Technical (Purity 95% w/w),
b) Diclosulam Technical (Purity 95% w/w),
c) Surfactant,
d) Dispersing agent, and
e) at least one agriculturally acceptable fillers/ adjuvants.

2. The novel formulation of Pendimethalin and Diclosulam as claimed in claim 1 and the process of preparation comprises the following steps:
a) Step 1: Preparation of the slurry of the formulation of Pendimethalin and Diclosulam as claimed in claim 1.
b) Step 2: Mixing of the water to make homogeneous slurry.
c) Step3: Grinding with correct media size, type and strength to get the range of the particle size as required for the efficient particle size and suspensibility.
d) Step 4: Removal of moisture and first stage of granulation.
e) Step 5: Second stage granulation to achieve, bigger dispersible granules.
f) Step 6: Removal of dust and recycling the same into the dryer.
g) Step 7: The saturated air with very fine particles of Pendimethalin and Diclosulam is passed through a packed column scrubber and those particles are collected in the water streams and clean air is released into atmosphere, while the water is mixed the Pendimethalin and Diclosulam which is reused to make homogeneous slurry as described in step 2.
h) Step 8: The end-product is collected and packed as required.

3. The novel formulation of Pendimethalin and Diclosulam as claimed in claims 1-2, wherein the Pendimethalin in the range of 20-75% w/w and Diclosulam in the range of 0.5- 4% w/w are added.

4. The novel formulation of Pendimethalin and Diclosulam as claimed in claims 1-2, wherein the lignosulfonate is selected from Borresperse NA, Ufoxane 3A, Vanisperse CB and Reax 100 in the range of 1-5% w/w.

5. The novel formulation of Pendimethalin and Diclosulam as claimed in claims 1-2, wherein the surfactant is selected from a group consisting of sodium polycarboxylate, alkylated naphthalene sulfonate sodium salt, ethoxylated lignin sulfonate, sodium salt of phenol sulfonic formaldehyde condensate, polycondensate of sodium methyl naphthalene and formaldehyde, Sodium di isopropyl-naphthalene sulphonate condensate, alkylated naphthalene sulfonate blend, sodium dodecyl benzene sulfonate, sodium lauryl sulfate, polyoxyethylene (6 moles) synthetic primary C9/C11 alcohol and dioctyl sodium sulfo-succinate in the range of 2-10% w/w and the fillers are selected from the group of Kaolin, China clay and talc.

6. The novel formulation of Pendimethalin and Diclosulam as claimed in claims 1-2, wherein the composition is formulated as Water Dispersible Granule (WG).

7. The novel formulation of Pendimethalin and Diclosulam and the process of preparation as claimed in claims 1-2, wherein the wet grinding can be achieved by sand mills, the said wet grinding is carried out in various conditions to achieve desired particle size whereby the coating of the micro-particles is achieved. Thus, without making the paste of the product, improved dispersion and suspension properties are obtained by using grinding media of diameter 1 mm to 10 mm.

Dated this day of , 2022

Signature:
Name: Patel Ankit (Director)
, Description:
FORM 2
THE PATENTS ACT, 1970
(39 OF 1970)
&
The Patents Rules, 2003
COMPLETE SPECIFICATION
(See section 10; rule 13)
1. TITLE OF THE INVENTION – NOVEL FORMULATION OF PENDIMETHALIN AND DICLOSULAM AND PROCESS OF PREPARATION THEREOF
2. APPLICANT(S)
a) NAME: MEGHMANI INDUSTRIES LIMITED
b) NATIONALITY: INDIAN
c) ADDRESS: 5, 8 & 9 FLOOR, B-WING, SIDDHIVINAYAK TOWERS, NR. KATARIA ARCADE, S G HIGHWAY, MAKARBA, AHMEDABAD, GUJARAT – 380051

3. PREAMBLE TO THE DESCRIPTION
COMPLETE SPECIFICATION
The following specification describes the invention and the manner in which it is to be performed

NOVEL FORMULATION OF PENDIMETHALIN AND DICLOSULAM AND PROCESS OF PREPARATION THEREOF

FIELD OF THE INVENTION:

[0001] The present invention relates to a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof. The present invention particularly relates to a novel formulation of Pendimethalin and Diclosulam in the dry flowable form and process of preparation thereof. The present invention more particularly relates to a novel formulation of Pendimethalin and Diclosulam in the dry flowable form and process of preparation which is ecofriendly, less toxic and safe.

BACKGROUND OF THE INVENTION:

[0002] Weeds are considered as the unwanted plants that grow in human controlled places like fields, farms, gardens etc. Weeds can survive in any type of environmental conditions and have capability to reproduce rapidly. Thus, they are hazardous to the yield of crops as they compete with crops for essential factors like sunlight, nutrients and water. Weeds also deliver vectors and hosts for plant pathogens thereby providing them the opportunity to infect and worsen the quality of the crops. Hence, weeds prove to be detrimental to the growth and yield of crops.

[0003] In order to control the harmful effects of weeds on crops, an extensive range of active herbicide compounds have been developed. Many active herbicide compounds in different formulations are commercially available. The efficacy of these conventional herbicide compounds is restricted in controlling certain weeds. Thus, the problem of controlling a broad spectrum of weeds by a single herbicide product still exists. In present, several herbicidal formulations are used in comparatively high concentrations and volumes. This leads to higher cost of the product, phytotoxicity and damage to the desirable plant species.

[0004] Many researchers have developed a variety of chemicals and their formulations which are effective in controlling the unwanted vegetation. Nevertheless, there is a continuous requirement for novel compositions and methods to control the growth of weeds without harming the desirable plant species. Specifically, in view to achieve economical results and eco-friendly compositions, different efforts have been made to maximize the performance of known active ingredients. Also, there is a need of novel herbicidal compositions that have lower production and market cost.

[0005] Diclosulam (N-(2, 6-dichlorophenyl)-5-ethoxy-7-fluoro [1, 2, 4] triazolo [1, 5-c] pyrimidine-2-sulfonamide) is a synthetic herbicide of class triazolo pyrimidine sulphonamide which is highly effective for broadleaf weed control.

[0006] Diclosulam is chemically represented as below structure:

[0007] The molecular formula of Diclosulam is C13H10Cl2FN5O3S and molecular weight is 406.220 g/mol and having water solubility of 6.32 mg/ml at 20oC. It has a low aqueous solubility and is non-volatile. Based on its chemical properties, Diclosulam is mobile and may leach to groundwater. It tends to be moderately persistent in soil systems. It has low mammalian toxicity and has high potential for bioaccumulation.

[0008] Diclosulam is the herbicide from HRAC (Herbicide Resistance Action Committee) Group B class. Diclosulam is an off-white colored herbicide and is mostly used for control of annual and certain perennial broadleaf weeds when applied as soil, or foliar treatments in crops such as peanuts, soybeans, sorghum, potatoes, maize and cereals like wheat, barley and oats.

[0009] Diclosulam inhibits the acetolactate synthase (ALS) enzyme. The primary site of Diclosulam activity is within the chloroplasts in meristems of plant. Diclosulam is taken up by both roots and foliage and translocated to new growing points. Lethal amounts of Diclosulam accumulate in meristems, halting cell division which results to death of the unwanted plants. Diclosulam is usually formulated as Wettable Granules (WG) for foliar and soil application.

[0010] Pendimethalin is a selective dinitroaniline herbicide used to control the growth of most annual grasses and many annual broad-leaved weeds in cereals, onions, leeks, garlic, fennel, maize, sorghum, rice, soya beans, peanuts, brassicas, carrots, celery, black salsify, peas, field beans, lupins, evening primrose, tulips, potatoes, cotton, hops, pome fruit, stone fruit, berry fruit (including strawberries), citrus fruit, lettuce, aubergines, capsicums, established turf, and in transplanted tomatoes, sunflowers, and tobacco. Pendimethalin is listed in the K1-group according to the Herbicide Resistance Action Committee (HRAC) classification.

[0011] The IUPAC name of Pendimethalin is N-(1-ethylpropyl)-3, 4-dimethyl-2, 6-dinitrobenzenamine and the molecular formula is C13H19N3O4. The relative Molecular mass of Pendimethalin is 281.31 g/ mol. The solubility of Pendimethalin in water is 0.3 mg/l at 20 ºC. It is readily soluble in benzene, toluene, chloroform and dichloromethane and slightly soluble in petroleum ether and petrol.

[0012] Pendimethalin is chemically represented as below structure:

[0013] Pendimethalin acts both pre-emergence, that is before weed seedlings have developed, and initial post-emergence. Pendimethalin has an ability to inhibit root and shoot growth. It controls the weed population and prevents weeds from developing, particularly during the crucial development phase of the crop. Its primary mode of action is to prevent plant cell division and elongation in susceptible species. Pendimethalin is usually formulated emulsifiable or emulsion concentrate that is mixed with water and used as a spray.

[0014] A conventional herbicidal Pendimethalin is available in the market in two different formulation: (A) Emulsion Concentrate (EC) formulation which contains hazardous solvents in the formulation which are harmful to the environment and causes inhalation toxicity in farmers while spraying the herbicide, (B) Encapsulated Suspension (CS) formulation freezes at low temperature and agglutinates the particles which causes settling issues on storage of the product.

[0015] Further, a conventional herbicidal Diclosulam Water Dispersible Granules (WG Extruded) is generally produced by blending of Diclosulam technical with dispersants and fillers, which is further micro-pulverized either in jet mill or ultra-fine pulverizing mills and then granulated with conventional granulators and dried. The average particle size D50 of conventional Diclosulam WG is around 20 microns. This product normally is a highly compacted, strongly bonded product with poor dispersion, and thus does not disperse well in water. This results in requirement of vigorous stirring the product without which the product is not evenly distributed through the spray media resulting in uneven spraying and lower efficacy. Hence, the disintegration of particles in water at the time of application by the farmer acts as a critical parameter for the effectiveness of the conventional product.

[0016] Over the years, human have understood the hazardous effects of herbicides towards mankind and environment. Thus, there is a growing need to improvise the conventional herbicidal products in such a form that is more efficient, efficacious and reduces the risk to the user. Also, a further improved composition having enhanced physical properties and more efficient bio-efficacy properties is much needed.

[0017] In India or anywhere in the world, in agricultural production, using synthetic or chemical agent is the most effective means in order to control weeds. However, the main disadvantage of such herbicide is that on long run, the weeds develop the resistance towards that herbicide and as a result to produce effective result, higher concentration of the herbicide is to be used. Here again using higher dose of herbicide may result in some detrimental effect to soil as well as environment. Therefore in general practice, usually combination of herbicide with another pesticide or another herbicide or fungicide is used in different concentration as per requirement.

[0018] However, when combination of one or more herbicide are used, the main challenge comes is to develop a formulation or composition which is stable, easy to use and effective. The present invention satisfies the existing needs, as well as others, and generally overcomes the deficiencies found in the prior art.

[0019] CN108651460 describes a composite herbicide composition, characterized in that it is composed of the following raw materials in parts by weight: 5-9 parts of acetochlor EC, 0.3-0.8 parts of cyhalofop-butyl, 2-7 parts of lignin, Pendimethalin 0.4-0.9 parts, Diclosulam 0.5-1 parts, borax 5-9 parts, acetochlor 0.3-0.7 parts, alkylbenzene sulfonic acid 0.5-0.9 parts, arsenate 2-5 parts, carbamate 0.3 -0.7 parts, 0.4-0.8 parts of nitrophenol, 0.4-0.7 parts of triasulfuron, 0.2-0.7 parts of quinclorac, 0.1-0.4 parts of p-phenylenediamine, 0.3-0.7 parts of flumetsulam, three 0.2-0.7 parts of chloroacetic acid, 0.2-0.6 parts of cyhalofop-butyl, 0.1-0.5 parts of pinoxaden, 0.3-0.7 parts of pyrethroids, 0.4-0.7 parts of organosiloxanes, 0.4-0.8 parts of chlorantraniliprole Parts, 5-9 parts of soybean oil and 7-12 parts of castor oil. This prior art does not comprise combination of Diclosulam and Pendimethalin in dry flowable form. Further, this prior art relates to a combination of herbicides with other insecticides. While, the present invention does not include any insecticide in the composition.

[0020] Indian Patent 252/DELNP/2014 disclose a synergistic herbicidal composition comprising an herbicidally effective amount of (a) penoxsulam and (b) pendimethalin. This prior art does describe the combination pendimethalin with triazolo pyrimidine sulfonamide herbicide but nowhere discloses combination of diclosulam and pendimethalin in dry flowable form.

[0021] Indian patent 201711013636 relates to ZE herbicidal 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. This prior art does not comprise combination of diclosulam and pendimethalin in dry flowable form.

[0022] US2016174551 relates to a ZC composition comprising: a) microencapsulated pendimethalin; and b) suspension concentrate of a co-herbicide, wherein the suspension concentrate comprises particles of a first herbicide selected from the group consisting of sulfonylurea herbicides, triazinone herbicides, imidazolinone herbicides, triazine herbicides, anilide herbicides, sulphonamide herbicides, organophosphorus herbicides, amide herbicides or alkanamide herbicides. This prior art does describe the combination of pendimethalin with triazolo pyrimidine sulfonamide herbicide but nowhere discloses the combination of diclosulam and pendiemthalin in dry flowable form.

[0023] However, there is no formulation or composition available where Diclosulam and Pendimethalin are combined in dry flowable form which is stable and yet effective.

[0024] In the present invention, inventors have arrived to novel formulation of Pendimethalin and Diclosulam in dry flowable form and the process of preparation which is stable, effective and overcome all the problems mentioned in prior art as described herein.

OBJECT OF THE INVENTION

[0025] The principal object of the present invention is to provide a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof.

[0026] Another object of the present invention is to provide a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in dry flowable form which is more eco-friendly and eliminates the hazardous effects of harmful chemicals caused to farmers by inhalation toxicity.

[0027] Yet another object of the present invention is provide a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in dry flowable form which is effective against a broad spectrum of weeds.

[0028] Yet another object of the present invention is to provide a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in dry flowable form which reduces the adverse effects of the various toxicity on the human body more particularly inhalation toxicity and reduces environmental damage and hazards.

[0029] Another object of the present invention is to provide an improved process to manufacture superior composition of Pendimethalin and Diclosulam in dry flowable form.

[0030] Yet another object of the present invention is to provide a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in dry flowable form which is easily dispersible in water.

[0031] Yet another object of the present invention is to provide a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in dry flowable form which provides enhanced herbicidal effectiveness on weeds and undesirable plants which in turn results in good yield.

SUMMARY OF THE INVENTION

[0032] The present invention discloses a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in dry flowable form comprising: Pendimethalin Technical in the range of 20-75% w/w, Diclosulam Technical in the range of 0.5-4.0 % w/w, Surfactant in the range of 1-10% w/w, Dispersing agent in the range of 1-8% w/w and Fillers or adjuvants. The present invention more particularly discloses a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof which is easily dispersible in water, eco-friendly, safe to handle, decreases inhalation toxicity, cost-effective and effective against a broad spectrum of weeds.

DETAILED DESCRIPTION OF THE INVENTION

[0033] The following is a description of embodiments of the present invention. The embodiments are in such details as to clearly communicate the invention. 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 invention.

[0034] Unless specifically defined otherwise, all technical and scientific terms used herein shall be taken to have the same meaning as commonly understood by one of ordinary skill in the art. 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.”

[0035] 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.

[0036] In some embodiments, the numerical parameters set forth in the written description are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment.

[0037] As used herein, the term "herbicide" or related terms means capable of being toxic to a plant (e.g., a weeds), controlling a plant, killing a plant, inhibiting the growth of a plant, and/or inhibiting the reproduction of a plant.

[0038] As used herein, the term "weed" means any plant targeted for treatment with a formulation of the invention. Target plants can be nuisance, unwanted, noxious, weedy, invasive, or harmful plant or vegetation (e.g., harmful to animals, harmful to ornamental plants, crops, etc.).

[0039] The present invention is all about providing a novel formulation of Pendimethalin and Diclosulam and process of preparation thereof, wherein the said composition is in Water Dispersible Granule (WDG/ WG) formulation. The international accepted nomenclature is “WG”.

[0040] As per one embodiment, the present invention provides a stable herbicidal Water Dispersible Granule (WDG/ WG) comprising Pendimethalin and Diclosulam with the following mass percentage of the composition:
Sr. No. Raw Material Concentration range (% w/w)
1 Pendimethalin Technical (Purity 95% w/w) 20 - 75
2 Diclosulam Technical (Purity 95% w/w) 0.5 - 4.0
3 Surfactant 1-10
4 Dispersing agent 1 – 8
5 Fillers/ adjuvants QS

[0041] Active ingredient is the actual chemical in the product mixture that controls the weeds. Active ingredient plays a key role in the functioning of the product mixture.

[0042] As per one embodiment, the active ingredient for the present invention is Pendimethalin and Diclosulam, wherein the concentration range of Pendimethalin is in the range of 20-75% w/w and Diclosulam is in the range of 0.5 – 4% w/w in WG formulation.

[0043] The concentration range of surfactant in the herbicidal composition of the present invention is in the range of 1-10% w/w. The surfactant is selected from a group consisting of sodium polycarboxylate, alkylated naphthalene sulfonate sodium salt, ethoxylated lignin sulfonate, sodium salt of phenol sulfonic formaldehyde condensate, polycondensate of sodium methyl naphthalene and formaldehyde, Sodium di isopropyl-naphthalene sulphonate condensate, alkylated naphthalene sulfonate blend, sodium dodecyl benzene sulfonate, sodium lauryl sulfate, polyoxyethylene (6 moles) synthetic primary C9/C11 alcohol, dioctyl sodium sulfo-succinate, etc.

[0044] A dispersing agent is a substance which adsorbs onto the surface of a particles and helps to preserve the state of dispersion of the particles and prevents them from re-aggregating. Dispersing agents are added to agrochemical formulations to facilitate dispersion and suspension during manufacture, and to ensure the particles re-disperse into vehicle or carrier. The concentration range of dispersing agent in the herbicidal composition of the present invention is in the range of 1-8% w/w. The dispersing agent in the present invention is selected from a group of lignosulfonate comprising Borresperse NA, Ufoxane 3A, Vanisperse CB and Reax 100.

[0045] An adjuvant is an additive which is added to make the formulations more effective, that improves or enhances application, performance, safety, storage, or handling of an active ingredient. Adjuvants include materials such as fillers, binders, stickers, stabilizers, antifreeze, antifoam, etc. Fillers in the present invention are selected from a group consisting of china clay, Kaolin, Talc, etc.

[0046] In yet another embodiment of the present invention, the benefits of a novel formulation of Pendimethalin and Diclosulam and process of preparation are described as follows:
1. Increased bio-efficacy by reduction in particle size as the surface area of product particles is higher.
2. Novel combination of Diclosulam and Pendimethalin in dry flowable form.
3. Reduced inhalation toxicity towards human and other mammals than individual products.
4. Ecofriendly.
5. Easy to manufacture.
6. Effective on wide range of weeds without harming the desired crop.
7. Easily gets dispersed in water.
8. Better flowability.
9. Product is adapted to use practices by farmers.

[0047] In yet another embodiment of the present invention there is provided a process for preparation of Pendimethalin and Diclosulam Water Dispersible Granule (WG) formulation. In the present invention, slurry is prepared by mixing Pendimethalin, Diclosulam and adjuvants like surfactants, dispersing agents, wetting agents and fillers as described in the above disclosed composition in a tank with the help of multi-stirrer and fan stirrer or similar silverson type mixers. The agglomerated particles are allowed to pass through a bead mill or sand mill or dyno mills after they broken into smaller sizes. Particle size analysis is carried out of a sample collected from the output of the slurry. After being convinced that the majority of the particles are between 0.5-5 microns, the slurry is pumped and stored. A pump feds the slurry into the drying chamber from the tank and the flow rate can be controlled precisely with the help of a flow chamber. The slurry then obtained is dried in the below mentioned process:
(i) Removal of moisture and first stage granulation: While the slurry is being sprayed as mentioned above, the hot air at a temperature between 100oc to 250oc is fed from the top of the chamber from a specially designed wing inserter. The hot air mixes with the atomized spray of formulated mass from the nozzle and thus it is dried slowly and agglomerated.
(ii) Second stage granulation: The agglomerated granules and particles which are not completely dried and having 5-10% moisture left are met with bottom integrated fluid bed drier from lower part of the spray drier main chamber. In the spray drier main chamber, the hot air is allowed to blow at 60oc to 100oc through a fluidized bed so that the already onion skin granules move up to meet the top spray product and raspberry type granulation takes place.
(iii) Removal of dust and recycling: The granules formed by the step (ii) are then allowed to come out through the rotary valve and then are dried into a horizontal post fluid bed drier where dust is again separated and re-fed into the drying chamber.
(iv) Release of dust-free air and collection of granules: The saturated hot air goes through two top outlets along with some fine particles through cyclone separator. The fine particles are then collected and re-fed into the bottom of the system via rotary valve. The saturated air having very less fine particles is passed through a column scrubber. The clean dust free air is then released into the atmosphere.

[0048] In yet another embodiment of the present invention, the physical properties of the novel combination of Pendimethalin and Diclosulam obtained by the above mentioned process is disclosed. It was observed in the preliminary trials that the product performs better than the conventional individual products. This was due to better particle size, better dispersion properties and better formulation recipe. These properties of the product of present invention allow all the particles to be well distributed while spraying and the product is farmer friendly.

[0049] The following examples are meant to illustrate the present invention. The examples are presented to exemplify the invention and are not to be considered as limiting the scope of invention. All the ingredients in the following examples are added to water to make up the composition, which may vary from 20-70%.
EXAMPLE
Example 1: Herbicidal Wettable Dispersible Granule (WG) composition of the present invention.
Sr. No. Chemical Composition Percent (% w/w)
1 Pendimethalin Technical (Purity 95% w/w) 21
2 Diclosulam Technical (Purity 95% w/w) 0.63
3 Sodium Polycarboxylate 1
4 Sodium di-isopropyl naphthalene sulphonate condensate 2
5 Borresperse NA 6
5 China clay 69.37

[0050] The ingredients mentioned above are mixed together to form a substantially homogeneous slurry. The resulting slurry is then milled to produce an average particle size approximately 1 to 2 microns. The slurry is then dried in the spray drier having inlet temperature of 120oc to 140oc and outlet of 50-51oc approximately.

Example 2: Slurry is made as disclosed in example 1 using the following ingredient.
Sr. No. Chemical Composition Percent (% w/w)
1 Pendimethalin Technical (Purity 95% w/w) 42
2 Diclosulam Technical (Purity 95% w/w) 1.4
3 Alkylated naphthalene sulfonate sodium salt 2
4 Alkylated naphthalene sulfonate blend 2
5 Ufoxane 3A 5
5 Kaolin 47.6

[0051] The slurry is milled to an average particle size of approximately 1.5 to 2.5 microns. The slurry is dried out in the spray drier at inlet temperature of 120oc and outlet of 48-51oc. The resulting free flowing and light granular product has an average size of approximately 4 microns and water content less than 2%.

Example 3: Slurry is made as disclosed in example 1 using the following ingredient.
Sr. No. Chemical Composition Percent (% w/w)
1 Pendimethalin Technical (Purity 95% w/w) 63
2 Diclosulam Technical (Purity 95% w/w) 2.1
3 Sodium salt of phenol sulfonic formaldehyde condensate 5
4 Salt of Alkyl naphthalene sulfonic acid 1
5 Vanisperse CB 3
5 Talc 25.9

[0052] The slurry is milled to an average particle size of approximately 1 to 2.5 microns. The slurry is dried out in the chamber at inlet temperature of 110oc and outlet of 48-50oc. The resulting free flowing and light granular product has an average size of approximately 5-6 microns and water content less than 2%.

Example 4: Slurry is made as disclosed in example 1 using the following ingredient.
Sr. No. Chemical Composition Percent (% w/w)
1 Pendimethalin Technical (Purity 95% w/w) 70.0
2 Diclosulam Technical (Purity 95% w/w) 2.00
3 Polycondensate of sodium methyl naphthalene and formaldehyde 6
4 Sodium lauryl sulphate 1
5 Reax-100 2
5 China clay 19

[0053] The slurry is dried out in the chamber at inlet temperature of 100-105oc and outlet of 48-49oc. The resulting free flowing and light granular product has an average size of approximately 4-6 microns and more water content less than 2%.

[0054] From the results of the examples 1-4, that formulation of Pendimethalin and Diclosulam in dry flowable form and the process of preparation disclosed in the present invention are stable and superior to the standalone herbicide.

[0055] Although the foregoing invention has been described in some way by way of illustration and example of purposes of clarity of understanding, it will be readily apparent to those of ordinary skill in the art in light of the teachings of this invention that certain changes and modifications may be made thereto.