AU2012201789B2

AU2012201789B2 - Granule composition containing herbicide and method for preparation thereof

Info

Publication number: AU2012201789B2
Application number: AU2012201789A
Authority: AU
Inventors: Anthony Gerard Flynn; Tung Ngoc Le; Philip Edward Pentland
Original assignee: Eureka Agresearch Pty Ltd
Current assignee: Eureka Agresearch Pty Ltd
Priority date: 2011-04-01
Filing date: 2012-03-27
Publication date: 2014-08-14
Anticipated expiration: 2032-03-27
Also published as: AU2012201789A1; NZ599091A

Abstract

A herbicidal broadcast granule comprising at least one of oxyfluorfen and oryzalin in an amount of no more than 8% by weight based on the total granule and a water miscible carrier liquid in which at the at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 8% w/w at a temperature of 600C.

Description

P/00/011 Regulation 3.2 AUSTRALIA Patents Act 1990 ORIGINAL COMPLETE SPECIFICATION STANDARD PATENT Invention Title: GRANULE COMPOSITION CONTAINING HERBICIDE AND METHOD FOR PREPARATION THEREOF Applicant: Eureka! AgResearch Pty Ltd ACN 086 194 738 The following statement is a full description of this invention, including the best method of performing it known to me: 1 6067 JLB Granule Composition Containing Herbicide and Method for Preparation Thereof Field 5 This invention relates to granular compositions that comprise at least one of the herbicides oxyfluorfen and oryzalin and method for preparing the compositions. In particular, the invention relates to granular compositions that comprise at least one of oxyfluorfen and oryzalin in an amount of no more than 8% w/w oxyfluorfen and no more than 8% w/w oryzalin. 10 Background Oxyfluorfen and oryzalin are herbicides used for broad spectrum pre- and post-emergent control of annual broadleaf and grassy weeds in a variety of tree fruit, nut, vine, and field crops. They are also used in weed control in forestry uses. 15 Oxyfluorfen and oryzalin are difficult to formulate as a broadcast granule due to poor solubility in many solvents. As a consequence of this poor solubility in many solvents clay granules with these herbicides have been prepared using non-polar solvents such as "Solvesso 150" which is a mixture of alkyl substituted aromatics which 0 provide good solubility. Oxyfluorfen granules made utilising many solvents for oxyfluorfen tend form a fine dust rich in oxyfluorfen during storage. We believe the formation of the dust is due to the tendency of many of these solvents to gradually evaporate. This promotes the 25 formation of crystallites of oxyfluorfen at the surface of the granules. We believe that solvent and oxyfluorfen in the granules are drawn to the granule surface to replace material lost by evaporation by evaporation resulting in much of the oxyfluorfen "blooming" onto the surface of the granule over time. The crystallites formed by evaporation tend to dislodge from the granules in storage and handling, and fall to the 30 bottom of the container. The result is a dust of the active agent oxyfluorfen and a non-uniform granule product that comprises "hot regions" with undesirably high concentrations of herbicide and reduced loading on the interior of the granules. Also, granules comprising oxyfluorfen are frequently used in confined spaces such as 2 sheds and greenhouses, and the presence of a strong solvent odour in the granules is an impediment to a safe and pleasant work environment. The discussion of documents, acts, materials, devices, articles and the like is included 5 in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application. 0 It would be desirable to provide a broadcast granule comprising at least one of oxyfluorfen and oryzalin that is of more stable and consistent composition, and that can readily be used in a confined work environment. 5 Summary We provide a herbicidal broadcast granule comprising at least one of oxyfluorfen and oryzalin in solid form in an amount of no more than 8% by weight oxyfluorfen and no more than 8% by weight oryzalin based on the total granule, a water-miscible carrier liquid in which the at least one of oxyfluorfen and oryzalin is soluble in an amount of at 0 least 8% w/w at a temperature of 60*C and a carrier granule which is not an agglomeration of powder, wherein the carrier granule has a particle size in the range of 0.2 to 4mm in which a mixture of the at least one of oxyfluorfen and oryzalin and water miscible liquid carrier is absorbed. Preferably at least one of oxyfluorfen and oryzalin is soluble in the water miscible liquid carrier in an amount of at least 15%, 25 more preferably at least 20% and still more preferably at least 25% w/w at 60 0 C. In a preferred embodiment, we provide an oxyfluorfen broadcast granule comprising no more than 8% by weight oxyfluorfen based on the total granule weight and a water-miscible carrier liquid in which oxyfluorfen is soluble in an amount of at least 8% 30 on a weight/weight basis at a temperature of 60*C, more preferably at least 15%, still more preferably at least 20% and even more preferably at least 25% w/w at 600C. The carrier liquid preferably comprises a water miscible organic compound which is preferably a liquid at 1200C preferably a liquid at 800C. In one embodiment the 35 organic compound is a liquid at 600C. 3 We further provide a method of forming a herbicidal broadcast granule comprising at least one of oxyfluorfen and oryzalin in an amount of no more than 8% by weight oxyfluorfen and no more than 8% oryzalin based on the total granule weight, the 5 method comprising: providing a solution of at least one of oxyfluorfen and oryzalin in a mixture at an elevated temperature of preferably at least 400C (more preferably at least 50 0 C, still more preferably at least 550C and most preferably, about 60 0 C), the mixture comprising: 0 (i) water miscible carrier liquid in which at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 8% by weight at a temperature of 60*C based on the weight of water miscible carrier liquid and preferably in which at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 15% by weight at a temperature 60 0 C 5 based on the weight of water miscible solvent, and preferably in which at least one of oxyfluorfen an oryzalin is soluble in an amount of at least 20% by weight oxyfluorfen at a temperature 600C based on the weight of water miscible carrier liquid; (ii) water comprising at least 10% of the water-miscible carrier liquid on a .0 weight/weight basis; and applying the mixture at an elevated temperature (preferably of at least 400C, more preferably at least 500C, still more preferably at least 550C and most preferably, about 600C) to absorbent carrier granules to 25 provide active herbicide loaded granules having a loading of at least one of oxyfluorfen and oryzalin of up to 8% by weight of the total weight of loaded granules; and preferably further comprising cooling the granules to precipitate at least one of oxyfluorfen and oryzalin within the granules. 30 The mixture, in a preferred embodiment, is a solution comprising at least one of oxyfluorfen and oryzalin (preferably at least oxyfluorfen and most preferably both oxyfluorfen and oryzalin) dissolved therein. 4 We further provide a method of forming an oxyfluorfen broadcast granule comprising up to 8% by weight oxyfluorfen based on the total granule weight, the method comprising: providing a solution of oxyfluorfen in a mixture at an elevated temperature of 5 preferably at least 400C (more preferably at least 50 0 C, still more preferably at least 550C and most preferably, about 60 0 C), the mixture comprising: (i) water miscible carrier liquid in which oxyfluorfen is soluble in an amount of at least 8% by weight oxyfluorfen at a temperature of 600C based on the weight of water miscible carrier liquid, and preferably in which 0 oxyfluorfen is soluble in an amount of at least 15% by weight oxyfluorfen at a temperature 600C based on the weight of water miscible solvent, and preferably in which oxyfluorfen is soluble in an amount of at least 20% by weight oxyfluorfen at a temperature 600C based on the weight of water miscible carrier liquid; 5 (ii) water comprising at least 10% of the water-miscible carrier liquid on a weight/weight basis; and applying the mixture at an elevated temperature (preferably of at least 400C, more preferably at least 50*C, still more preferably at least 550C and most 0 preferably, about 600C) to absorbent carrier granules to provide active loaded granules having a loading of oxyfluorfen of up to 8% oxyfluorfen by weight of the total weight of loaded granules; and preferably further comprising cooling the granules to precipitate oxyfluorfen within the granules. 25 Generally we have found that the use of water soluble solvents and in particular the mixture of water-miscible organic solvent and water to absorb the oxyfluorfen into the granule reduces significantly the occurrence of fines in the granule composition particularly with storage and handling of the granule composition. Further the ability 30 to use water-miscible organic solvents generally allows compositions to be prepared 5 without the odour problem caused by the water-immiscible aromatic hydrocarbons previously used as solvent for manufacture of oxyfluorfen granules. The preferred granules comprise oxyfluorfen in an amount of from 0.1% w/w to 8% 5 w/w of the granule composition, more preferably 0.5% w/w to 5% w/w and still more preferably 0.5% w/w to 3% w/w of the granule composition. The granules may contain oryzalin as the herbicidal active which may be the sole active or may be in addition to oxyfluorfen. Oryzalin, in one set of embodiments, is 10 present in an amount in the range of from 0.1% w/w to 8% w/w of the granule composition, more preferably 0.5% w/w to 4% w/w and still more preferably 0.5% w/w to 1.5% w/w of the granule composition. The granules may comprise other herbicides or active agents if desired. However, in 15 one embodiment, the granule comprises no more than 2% of herbicidal active other than one or both of oxyfluorfen and oryzalin and more preferably no more than 1% w/w other herbicide. Throughout the description and the claims of this specification the word "comprise" 20 and variations of the word, such as "comprising" and "comprises" is not intended to exclude other additives, components, integers or steps. Detailed Description In one aspect there is provided a herbicidal broadcast granule comprising at least one 25 of oxyfluorfen and oryzalin an an amount of no more than 8% by weight oxyfluorfen based on the granule weight and no more than 8% w/w oryzalin based on the total granule weight and a water-miscible carrier liquid in which at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 8% on a weight/weight basis at a temperature of 600C, more preferably at least 15% and more preferably at least 20% 30 w/w at 6 0 "C. In a preferred aspect, there is provided an oxyfluorfen broadcast granule comprising no more than 8% by weight oxyfluorfen based on the total granule weight and a 6 water-miscible carrier liquid in which oxyfluorfen is soluble in an amount of at least 8% on a weight/weight basis at a temperature of 600C, more preferably at least 15% and more preferably at least 20%. 5 The water-miscible carrier liquid comprises a water-miscible organic compound and preferably also comprises water. The ratio of water miscible organic compound to water is preferably in the range of from 10:1 to 1:1 on a volume/volume basis, and preferably the volume ratio is in the range 6:1 to 2:1. 10 The term water-miscible liquid carrier refers to a water-miscible organic compound, optionally in admixture with water. The term water miscible organic compound refers to compounds comprising carbon and hydrogen and preferably at least carbon, hydrogen and oxygen and mixtures of 15 such compounds. Such compounds may optionally further comprise additional elements such as sulfur, nitrogen, phosphorus or the like. Compounds which are liquids at 1204C (preferably liquid at 80 0 C such as 600C) are preferred and such compounds consisting of the elements carbon, hydrogen and oxygen are particularly preferred.' The water-miscible organic liquid is preferably miscible in a 1 : 1 volume 20 ratio (or greater proportion of water-miscible organic liquid) with water at 200C. Examples of water-miscible organic carrier may, for example, be selected from the group consisting of C1 to C alkyl mono ethers of di- and tri-(C 2 to C4 alkylene) glycols and poly(alkylene glycol) particularly polyethylene glycol. More preferred water 25 miscible organic compounds are C1 to C alkyl mono ethers of at least one of diethylene glycol and triethylene glycol and polyethylene glycols of molecular weight from 200 to 10,000. One preferred class of water-miscible organic compounds are diethylene glycol mono alkyl ethers and triethylene glycol mono alkyl ethers wherein the alkyl is selected from methyl, ethyl, propyl and butyl and most preferably, 30 diethylene glycol monobutyl ether. The oxyfluorfen is preferably present in the granule composition as a particulate solid, preferably a crystalline particulate solid of solubility no more than 10% of the water 7 miscible carrier liquid on a weight/weight basis at 200C, preferably no more than 5% and most preferably no more than 3% at 20*C. The oryzalin may be present in the granule and when present is preferably a 5 crystalline particulate solid of solubility no more than 10% w/w in the water-miscible carrier liquid at 200C, preferably no more than 5% w/w and more preferably no more than 3% and still more preferably no more than 1% w/w at 200C. The porous carrier granule is preferably a clay granule, preferably attapulgite or 10 bentonite. The granule is preferably a coarse broadcast granule and is preferably not dispersible in water. The granule size is preferably in the range 0.2 - 4mm, more preferably in the size range 0.5 - 1.5 mm. Generally the granule composition may be free from surfactants although such 15 materials may be added if desired. Thus in one embodiment the granule composition comprises less than 5% by weight surfactant (preferably less than 2% by weight and still more preferably less than 1% by weight and most preferably is free of added surfactant). 20 The oxyflurofen is preferably present in the granule in solid form and more preferably in a form crystallised from a mixture of the water-miscible carrier liquid and water absorbed Into the granule at elevated temperature. The water-miscible organic compounds are preferably selected from the group 25 consisting of glycol ethers, preferably mono-(C 1 to C6 alkyl)ethers of di- or tri-(C 2 to C4 alkylene)glycols and preferably polyethylene glycols of molecular weight 200 to 10,000. One group of such compounds are diethylene glycol mono alkyl ethers and triethylene glycol mono alkyl ethers wherein the alkyl is selected from methyl, ethyl, propyl and butyl, and most preferably diethylene glycol mono butyl ether. 30 The water-miscible carrier liquid is preferably present in the granule composition in an amount of from 2% more preferably from 5% weight by weight. The upper limit will be governed by the specific composition but is typically no more than 20%, preferably no 8 more than 15% and still more preferably no more than 12% weight by weight of the total granule composition. In one preference the water-miscible organic compound with a low degree of odour is 5 blended with water to provide a polar liquid blend. Preferably the volume/volume ratio of water-miscible organic solvent to water is in the range 10:1 to 1:1. In one set of embodiments the oxyfluorfen broadcast granule further comprising a water soluble tackifying agent. The water soluble macromolecule (preferably a 10 polymer) is preferably a polymer and is preferably selected from the group consisting of polyvinyl pyrrolidine and cellulosic polymers such as hydroxypropylmethyl cellulose and ethyl cellulose. Polyethylene glycol may provide the role of water-miscible organic compound and tackifying agent. 15 In one embodiment, the composition is a blend of polyethylene glycols of different molecular weight, for example, one PEG of molecular weight up to 600 and one PEG of molecular weight above 600 such as 800 or above. Preferably the ratio of water-soluble macromolecule to water-miscible carrier liquid 20 (on a weight/weight basis) is in the range 0.03 to 0.15. More preferably the ratio of the water-soluble macromolecule to polar liquid is about 0.05 - 0.1. In one set of embodiments there is provided a method of forming an oxyfluorfen broadcast granule comprising up to 8% by weight oxyfluorfen based on the total 25 granule weight, the method comprising: providing a solution of oxyfluorfen in a mixture at an elevated temperature of preferably at least 40 0 C ( more preferably at least 50 0 C, still more preferably at least 55 0 C and most preferably, about 600C), the mixture comprising: 30 (i) water-miscible carrier liquid in which oxyfluorfen is soluble in an amount of at least 8% by weight oxyfluorfen at a temperature of 60 0 C based on the weight of water-miscible carrier liquid, and preferably in which oxyfluorfen is soluble in an amount of at least 9 15% by weight oxyfluorfen at a temperature 60*C based on the weight of water-miscible solvent, and preferably is which oxyfluorfen is soluble in an amount of at least 20% by weight oxyfluorfen at a temperature 60*C based on the weight of water-miscible solvent; 5 (ii) water comprising at least 10% of the water-miscible carrier liquid on a weight/weight basis; and applying the mixture at an elevated temperature (preferably of at least 40 0 C, more preferably at least 50 0 C, still more preferably at least 55*C and 10 most preferably, about 60 0 C) to absorbent clay granules to provide active loaded granules having a loading of oxyfluorfen of up to 8% oxyfluorfen by weight of the total weight of loaded granules; and preferably further comprising cooling the granules to precipitate oxyfluorfen within the granules. 15 The weight ratio of water miscible organic liquid to water used in the method is preferably in the range of from 10:1 to 1:1 on a weight/weight basis and wherein the water miscible organic liquid is used in a ratio with water in which it is miscible at the temperature at which the mixture is applied. 20 The water miscible organic liquid is preferably selected from the group consisting of C1 to C 6 alkyl mono ethers of di and tri C 2 to C 4 alkylene glycols, preferably C 1 to C 6 alkyl mono ethers of at least one of diethylene glycol and triethylene glycol, more preferably diethylene glycol mono alkyl ethers and triethylene glycol mono alkyl ethers 25 wherein the alkyl is selected from methyl, ethyl, propyl and butyl and most preferably, diethylene glycol monobutyl ether. The method will generally result in the oxyflurofen being at least partially crystallised from the water miscible carrier liquid absorbed into the granule at elevated 30 temperature. The cooling to provide crystallisation may take place under ambient conditions following application of the mixture to the granules. 10 The mixture applied to the granular composition may in preferred embodiments comprise in the range of from 10 to 80% by weight oxyfluorfen. 5 In one embodiment the granules of the invention further comprise an additional herbicide particularly a dinitroaniline herbicide particularly oryzalin. Preferably the dinitroaniline herbicide is chosen from the group consisting of oryzalin, pendimethalin and trifluralin. Preferably the dinitroaniline herbicide is oryzalin. Preferably oryzalin comprises 0.3 - 3% weight by weight of the final composition. In one set of 10 embodiments the composition of the invention comprises 1 - 3% weight oxyfluorfen and further comprises 0.5 - 1.5% by weight oryzalin based on the weight of the total composition. More preferably the granule composition comprises 1 - 3% oxyfluorfen and further comprises 0.5 - 1.5% oryzalin on a weight/weight basis, and still more preferably the broadcast granule comprises 1.5 - 2.5% oxyfluorfen and further 15 comprises 0.7 - 1.3% oryzalin. More preferably the composition of the invention comprises about 2% by weight oxyfluorfen and about 1% by weight oryzalin. The oxyfluorfen and oryzalin materials are preferably dissolved together in the carrier liquid at elevated temperature of at 20 least 400C, more preferably at least 500C, still more preferably at least 550C and most preferably, about 600C prior to application of said liquid to the carrier granule. The loading of oxyfluorfen on the granules is in one set of embodiments in the range of from 0.1% to 8% by weight, more preferably from 0.5% to 5% and most preferably 25 from 0.5 to 3% by weight. When the granule composition comprises both oxyfluorfen and oryzalin it is preferred that the method involves dissolving both oxyfluorfen and oryzalin in the mixture at elevated temperature preferably at least 40*C, more preferably at least 500C and still 30 more preferably at least 60*C and cooling the granule composition (preferably to ambient temperature) after applying the mixture to the granules. 11 The granule composition comprises a solid carrier. Examples of solid carriers useful for formulating the granular herbicides include clay, bentonite, talc, calcium carbonate, sodium carbonate, zeeklite, sericite, acid clay, quartzite, diatomaceous silica, pumice, zeolite, vermiculite, potassium chloride, urea, white carbon, ammonium 5 sulfate, sodium sulfate, perlite, magnesium sulfate, kaolin, attapulgite and the like; The more preferred carriers are generally attapulgite and kaolin including sodium kaoline and potassium kaolin and mixtures thereof. The solid carrier used in preparing the granule composition is not an agglomerate, 0 that is, the granule composition is of primary particles onto which the liquor comprising active agent oxyfluorfen and/or oryzalin and water-miscible carrier liquid are absorbed at elevated temperature without agglomeration of the particles. In other words the particles are un-agglomerated primary particles as distinct from secondary particles formed by agglomeration of primary powder particles much finer than the 5 secondary particles. Granules formed without agglomeration are generally less susceptible to formation of fines and are more effective in delivering herbicide by broadcasting of the solid granules. The solid carrier may constitute up to 97% by weight of the composition but will typically be up to 95% by weight of the herbicidal granule composition such as up to 92% w/w or up to 90% w/w. The solid carrier will 0 generally be at least 65 %w/w of the herbicidal granule composition such as at least 70 % w/w, at least 75 % w/w or at least 80 % w/w of the herbicidal granule composition In one embodiment of the method the mixture comprising carrier liquid and 25 oxyfluorfen and/or oryzalin is applied to granules in a rotatable drum by pouring the solution onto granules in the drum and rotating the drum to distribute the liquid among the granules. In a further aspect there is provided a method of controlling weeds comprising 30 broadcasting the herbicidal granules herein described onto land in which weed control is needed. The herbicide may be broadcast as the solid granules onto the site for weed control and the herbicide released from the granules by water from rainfall, 12 irrigation or other application of water onto the site on which the granules have been broadcast. The invention will now be described with reference to the following examples. It is to 5 be understood that the examples are provided by way of illustration of the invention and that they are in no way limiting to the scope of the invention. EXAMPLES Excipient chemical descriptions 0 13 0 l 00 a3() (D 0) - - L (U C C (n E CU 0 0 0L -C M a 2tl o*0 (n* 0).u cu E a) _ Eu a0 (DI 0 - 00Ec 0 EEU A? gu (n a) 2 Nu2o- )L )=3-a h 2I ) E e Cu r < a I-U 0 oC -3 0)4, CL) 0u 4) (D2 00 F- < a)e a) x0 c x.) - 5 C 1 0~ i a)c a c (D m 9- 2c0c CC) CU m 2 ) 0 ) a) U 2 00 750k E ) L) 00- C cu 0 (D a)0 a) 0)-L 0 1.-- 0 E -CCt CW0 a u) E0 00 0), 00E)n 2 F -- c0)&03 M 2 U a) ~ ~ ~ c c= r : - -C-ua w~~ 0 >-~ ~ Cu a).0 >( 0 0 w CU 0 0 M7 a - - n : EUDE 0 0 m 2m 2 > ( 0 UN L E C) Cu ) 00a () 0 0 >, "a) o- E < <i < CCn Ln 1- 0)0 0 zD -C )L 0C DV OC (o00)0C2 C? C-4 ?C?4 0 00) 0) Ict q c 0 C NC OC % o 04( NV )~ m - M 0 0 .0 0DV Cl) ~Cl __ _ _ (D 0 (D 14 Example 1 This Example provides data on the compatibility of various hydrophilic macromolecules and colloids mixed with a water-miscible carrier liquor, the mixture comprising a liquor made from 0.63 parts hydrophilic macromolecule or colloid, 2.1 parts oxyfluorfen technical grade (95% purity), 9.4 parts polar liquid blend (said blend made by adding 2.1 parts of water to 7.3 parts of butyl diicinol = butyl diglysolv = diethylene glycol monobutyl ether). Compatibility was assessed at 600C and was rated as positive if the resultant liquid remained substantially homogeneous over 30 minutes at this temperature. Hydrophilic macromolecule Compatibility Rutocel 60RT6 positive Bentone SD2 positive Active gel 150 negative Veegum T negative Cellulon PX negative Microcrystalline cellulose negative Ethyl cellulose positive Carboxymethyl cellulose negative Kollidon 30 (polyvinyl pyrrolidone) positive Rhodopol 50MC negative Aerosil 200 positive Permulen TR2-NF negative Carbopol negative Agar negative gelatine negative Corn flour negative kaolin negative Polyethylene glycol (PEG) 8000 positive Airvol 203S (PVA) negative 15 Example 2 In this example compositions were prepared by: (a) making a liquor as in example 1, but with the further addition of 1 part oryzalin for every 2 parts oxyfluorfen. This oryzalin acted as a colour marker for the oxyfluorfen crystals. The said liquor included a water-miscible carrier liquor, oxyfluorfen, oryzalin and a hydrophilic macromolecule or colloid; (b) heating the resultant material to 60 0 C with stirring; and (c) checking that the hot stirred resultant liquor is homogeneous and stable for at least 30 mins, and if so, adding the hot resultant liquor to kiln dried "plus 300 micron" attapulgite. In this addition step 10.6 parts hot resultant liquor was added to 70 parts attapulgite; (d) shaking the loaded hot attapulgite in a closed container to uniformity and then weighing the uniform loaded attapulgite; (e) allowing the loaded attapulgite to rest at room temperature for 30 minutes after weighing; (f) weighing the amount of rested loaded attapulgite retained on a 300 micron sieve and (g) calculating the percentage of rested loaded material that passed through the 300 micron sieve. The above protocol was designed to measure the formation and dislodgement of fine oxyfluorfen crystals from the loaded attapulgite in storage. Dislodgement of fine material from the loaded carrier granules was the main failure mechanism for the formulation. Hydrophilic Percentage of Comments Colour of final macromolecule loaded attapulgite product included in liquor passing through 300 micron sieve none 0.32 fine material orange Rutocel 60RT6 0.21 relatively few fines yellow Bentone SD2 0.54 fine material orange Ethyl cellulose 0.1 relatively few fines yellow Kollidon 30 0.1 relatively few fines yellow Aerosil 200 1.0 fine material orange Polyethylene glycol 0.32 fine material orange PEG 8000 16 Note: The better formulations were noted to have an orange colour after drying and storage at room temperature. Example 3 Production of broadcast granule comprising 20g/kg oxyfluorfen and 10g/kg oryzalin. Component Concentration (g/kg) Oxyfluorfen tech (95%) 21.05 Oryzalin tech (95%) 10.53 Rutocel 60RT6 6.30 Butyl Diglysolv 73.15 Water 21.10 Bentonite granules (kiln dried) 867.87 TOTAL 1000 Supplier details: Butyl glysolv Company: Huntsman Rutocel 60RT6 Company: Redox Pty Ltd Bentonite granule (kiln dried) Company: Arumpo Bentonite Pty Ltd Excipient chemical descriptions Trade Name Chemical Name CAS No. Function Rutocel 60RT6 Hydroxymethyl propyl 9004-65-3 Hydrophilic cellulose macromolecule Butyl Glysolv Ethylene glycol monobutyl 111-76-2 Polar Solvent ether Water 7732-18-5 Solvent Bentonite (kiln dried) Montmorillonite 1302-78-9 Porous Carrier 17 Manufacturing procedure The following manufacturing procedure has been developed on laboratory scale equipment. Method of preparation Step 1 To a mixing vessel: Add Oxyfluorfen, Oryzalin, Butyl diglysolv and Rutocel 60RT6. Step 2 Mix together ingredients using the Dispermat@ N1 Step 3 Add water to mixing vessel and mix with Dispermat@ N1 Heat mixture to 65 0 C to dissolve the active ingredients. A clear orange Step 4 coloured solution should result. Step 5 Pour mixture over bentonite granule and mix until uniform. Step 6 Allow mixture to dry. Quality Control At the completion of the manufacturing process a sample is provided to QC lab and the following tests completed: Physical tests Test method Limits Oryzalin EURI175 (see example 5) 7.5-12.5 g/kg Oxyfluorfen EUR 175(see example 5) 15-25 g/kg Appearance Visual Match to standard State Visual Match to standard Colour Visual Match to standard Odour Olfactory Match to standard pH MT 75 (CIPAC) 6 - 7 @ 19.7*C Bulk density Pour: 0.88 - .92 g/ml MT 186 (CIPAC) Tap: 0.92 - 0.96 g/ml Dust content MT 171 (CIPAC) Non-dusty Attrition resistance MT 178 (CIPAC) > 98% 18 Active Ingredient Stability Active ingredient Limits Ambient Stability temperature 2 weeks @ 54*C Oryzalin 7.5-12.5 g/kg 9.1 9.4 Oxyfluorfen 15-25 g/kg 18.6 20.3 Physical stability Ambient 2 weeks @ 54*C Physical Test Limits tests method Appearance Visual n/a Yellow granules Yellow granules State Visual n/a Solid Solid Colour Visual n/a Yellow Yellow Odour Olfactory n/a Characteristic Characteristic pH MT 75 n/a 6.31 @ 19.7 0 C 6.27 @ 19.4 0 C Bulk density MT 186 n/a Pour: 0.90 g/ml Pour: 0.90 g/ml (CIPAC) Tap: 0.94 g/ml Tap: 0.92 g/ml Dust content MT171 Non-dusty Non-dusty Non-dusty (CIPAC) Attrition MT178 > 98% 99.5% 99.6% resistance (CIPAC) Packaging Storage stability in HDPE No change No distortions No distortions (54 0 C X on storage 2 weeks) Example 4 Solubility of active agents at various water ratios with butyl diicinol (TUNG to supply). Various ratios of butyldiglycol and water were prepared and sufficient oxyfluorfen added to provide a 17.3% w/w Oxyfluorfen material. 19 RATIO of butyl diglycol Solubility at 20*C Solubility at 60*C to water 3.5: 1 (formulation) no Yes 100% water no No 100% butyl diglycol no Yes 1:1 no No 1:3.5 (reversed) no No 1:9 no No 9:1 no yes Example 5 Determination of Oryzalin and Oxyfluorfen in a Granule by High Performance Liquid Chromatography. A 500mg sample of test granules was diluted with acetonitrile to 100ml to give an assay solution. Assay was by High Performance Liquid Chromatography using a 5 micron HS C-18 column and UV Vis detection. This gave a relationship between peak area and analyte concentration which was used to calculate the concentration of oryzalin and oxyfluorfen from a calibration curve previously derived from the analysis of standard solutions. A carefully prepared representative series of five samples was taken from a prepared liquid formulation as well as a series of four samples 'spiked' with a known amount of standard grade active ingredient. Each sample was then analysed by RP-HPLC using an Alltech Adsorbosphere HS (C18) 250mm x 4.6mm column and UV-Vis detection. The grams per kilogram content of oryzalin and oxyfluorfen was determined from a calibration graph (response of active ingredient versus concentration of active ingredient) derived from the analysis of standard solutions. This method is applicable to the determination of oryzalin and oxyfluorfen in granule formulations, specifically 10 g/kg and 20 g/kg WG formulations in the matrix of granules typical of the granules of the invention. 20 The HPLC was a GBC LC1 120 iscoratic pump equipped with a GBC LC1200 UV-Vis detector, data handling by WinChrom. The analytical column was an Alltech Adsorbosphere HS (C18) column 250mm (1) 4.6mm (id). The chromatographic conditions were: Column: Alltech Adsorbosphere HS (C18) column 250mm (1) 4.6mm (id) Column Temperature: Ambient Mobile Phase: Eluent A: 85% acetonitrile: Eluent B: 15% MilliQ water Injection Volume: 20 ul Detector wavelength: 280 nm Retention time: 3.9 min (Oryzalin) 6 min (Oxyfluorfen) @ 1.OmL/min Chromatogram length: 10 min Preparation of 10 g/kg oryzalin 20g/kg oxyfluorfen granule samples. When analysing the granule a sample of approximately 500mg was weighed by difference into 100ml volumetric flask and its mass was recorded accurately. The sample was then dispersed with the minimum required amount of Acetonitrile, made to the mark and inverted to ensure homogeneity. It was demonstrated that all significant impurities of oryzalin and oxyfluorfen are separated in the chromatogram. Therefore there was no interference from impurities in the determination. 21 Example 6 Bioefficacy and comparison with prior art product. Summary At a plant nursery (Botanix) at Carrum Downs, Victoria, two granular products were applied to the bare soil around the base of ornamental plants in the nursery pots. The first granular product was designated Crop Culture Tour Ornamental Herbicide, it contained Oryzalin 10 g/kg and Oxyfluorfen 20 g/kg, was a granule according to the invention (see example 3). The second granular product also contained Oryzalin 10 g/kg and Oxyfluorfen 20 g/kg , and was designated Rout Ornamental Herbicide. This second granular product was not a granule according to the invention, and was based on the use of an aromatic (high-odour) water-insoluble carrier liquid to load active ingredients into the granule. The effect on the plant species and the level of weed control were assessed over the following 4 months. Results from this trial showed: Crop Culture Tour Ornamental Herbicide (CC Tour) and Rout Ornamental Herbicide were effective in controlling the weeds that were present. CC Tour achieved equivalent levels of weed control to the industry standard. There was no difference in the level of control when both products were applied at the same rate. None of the three plant species, Crepe Myrtle (Lagerstroemia indica), Black Sheoak Casuarina littoralis or Double Rose Pink Oleander (Nerium oleander) showed signs of herbicide phytotoxicity from the application of Crop Culture Tour or Rout Ornamental Herbicide. Trial Aims: 1. To evaluate Crop Culture Tour for pre-emergent control of various weeds in nursery pots. 22 2. To compare Crop Culture Tour to the industry standard, Rout Ornamental Herbicide. Methods and Materials Site Details: Site Site Botanix Plant Nursery Co-operator Carl Soderlund Contact 0419117286 Address Learmonth Road Carrum Downs, Vic 3201 Soil Type Loam potting mix pH 7.0 Tilth Good Organic Matter High Fertility Good Trial Design Randomised Plot Size Single pots Replications 4 Crop Types Common Name Crepe Myrtle Black Sheoak Doule nderPink Species Lagerstroemia indica Casuarina littoralis Nerium oleander Site History Chemicals Used * No chemicals used Fertiliser Used * Nil *21 Days prior and post trial application Plot Size Crepe Myrtle & Black Sheoak 40cm pots (0.1257 M 2 ) 23 Oleander 30cm pots (0.0707 M 2 ) Application Details Date: 15-07-2009 Time: 1:10 - 3:55 pm Wind: SW 2-5 km/hr Temp: 11 - 13 0 C Humidity: 56 % Cloud Cover: 80 % Spray Order: 2, 3, 4, 5, 6, 7 Treatments were applied by gentling sprinkling the measured amount of each product to the surface of the plant pot. Formulations Used Code Details Formulation Active Ingredient and Concentration CC Tour Crop Culture Tour Oryzalin 10 g/kg Ornamental Herbicide granule Oxyfluorfen 20 g/kg Rout Rout Ornamental granule Oryzalin 10 g/kg Herbicide Oxyfluorfen 20 g/kg Treatments TTT Product Trial Code / BN Rate g per 40cm g per 30cm No. kg/ha pot pot 1 Untreated 2 CC Tour 50 0.628 0.354 3 CC Tour 100 1.257 0.707 4 CC Tour 200 2.514 1.414 5 Rout 50 0.628 0.354 6 Rout 100 1.257 0.707 7 Rout 1200 2.514 1.414 24 Target Weeds Black Double Common Name Scientific Name Crepe Myrtle Sheoak Rose Pink Oleander Chickweed Stellaria media 0 Cotula Cotula australia 0 Dandelion Taraxacum officinale 0 0 0 Deadly Nightshade Solanum dulcamara 0 Flatweed Hypochaeris radicata 0 0 Flick Weed (Willow Epilobium ciliatum 0 0 herb) Fumitory, Pink Fumaria officinalis 0 Assessment Methods (i) Plant Phytotoxicity Each plant in each pot was observed to determine if there were any effects of pesticide induced phytotoxicity compared to the plants in the untreated pots. (ii) Weed Control Weeds present in each plant pot were assessed at 134 days after application. Analysis Results were analysed using One-Way Analysis of Variance and where the Fcalc was significant (P<0.05) mean plot values were compared using LSD, means sharing common postscripts are not significantly different (LSD test, P<0.05). Because the plant numbers were low, analyses were conducted on the total plants per pot. Analyses were conducted both including and excluding the untreated pots. Assessment & Assessment Timings Assessment Days After Assessment Type Number Treatment 1 35 Plant Phytotoxicity 2 76 Plant Phytotoxicity 3 134 Plant Phytotoxicity & Weed Counts 25 RESULTS Efficacy Weeds present in each plant pot were assessed 134 days after application (1 34DAT). The weeds present varied for each of the plant species, Section 2.5, and although the numbers were low this is a function of the pot size. The weeds present are shown in tables 1, 2 and 3 below. Table 1. Weeds per Pot - Black Sheoak (Casuarina littoralis) - 134 DAT Dandelion Neadly Flatweed Total Weed DneinNightshade __________ Treatments 1. Untreated 3.5 2.0 1.8 7.3 a 2. CC Tour - 50 kg/ha 0.3 0.5 0.3 1.0 b ab 3. CC Tour - 100 kg/ha 0.3 0.0 0.5 0.8 b b 4. CC Tour - 200 kg/ha 0.5 0.0 0.0 0.5 b b 5. Rout - 50 kg/ha 1.0 0.8 0.8 2.5 b a 6. Rout - 100 kg/ha 0.3 0.3 0.5 1.0 b ab 7. Rout - 200 kg/ha 0.3 0.0 0.0 0.3 b b LSD (p<0.05) L 2.683 1.645 Table 2. Weeds per Pot - Crepe Myrtle (Lagerstroemia indica) - 134 DAT Weed Chickweed Cotula Treatments 1. Untreated 2.5 3.5 2. CC Tour - 50 kg/ha 0.5 1.8 3. CC Tour - 100 kg/ha 0.3 0.0 4. CC Tour - 200 kg/ha 0.0 0.0 5. Rout - 50 kg/ha 0.8 1.8 6. Rout - 100 kg/ha 0.3 0.5 7. Rout - 200 kg/ha 0.3 0.0 26 Weed Dandelion Flick Weed Total Treatments 1. Untreated 1.8 2.5 10.3 a 2. CC Tour - 50 kg/ha 0.3 0.3 2.8 b ab 3. CC Tour - 100 kg/ha 0.3 0.3 0.8 b ab 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 b b 5. Rout - 50 kg/ha 0.3 0.5 3.3 b a 6. Rout - 100 kg/ha 0.3 0.0 1.0 b ab 7. Rout - 200 kg/ha 0.0 0.0 0.3 b b LSD (p<0.05) 3.717 1.645 Table 3. Weeds per Pot - Double Rose Pink Oleander (Nerium oleander)- 134 DAT Weed Chickweed Dandelion Treatments 1. Untreated 2.0 1.5 2. CC Tour - 50 kg/ha 0.3 0.0 3. CC Tour - 100 kg/ha 0.3 0.0 4. CC Tour - 200 kg/ha 0.0 0.0 5. Rout - 50 kg/ha 0.5 0.3 6. Rout - 100 kg/ha 0.3 0.0 7. Rout - 200 kg/ha 0.3 0.0 Weed Flick Weed Fumitory, Pink Total Treatments 1. Untreated 1.5 2.5 7.5 a 2. CC Tour - 50 kg/ha 0.3 0.0 0.5 b 3. CC Tour - 100 kg/ha 0.3 0.0 0.5 b 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 b 5. Rout - 50 kg/ha 0.3 0.5 1.5 b 6. Rout - 100 kg/ha 0.3 0.0 0.5 b 7. Rout - 200 kg/ha 0.0 0.0 0.3 b LSD (p<0.05) 2.816 NS 27 DISCUSSION Weed Counts For each plant species the weeds present in the pot were significantly reduced by the addition of Crop Culture Tour or Rout, Tables 1, 2 & 3. Equal rates of CC Tour and Rout gave the same (statistically) level of weed control in each of three different plant species pots, Tables 1, 2 & 3. For the weeds present in the Black Sheoak pots, Dandelion, Deadly Nightshade and Flatweed, the low rate of Rout although not significantly different to the low rate of CC Tour and 100 kg/ha Rout was significantly inferior to the 100 and 200 kg/ha rates of CC Tour and Rout at 200 kg/ha, Table 1. In the Crepe Myrtle pots, the weeds present; Chickweed, Cotula, Dandelion and Flatweed, were controlled least by the low rate of Rout, which was not significantly different to the .CC Tour at 50 and 100 kg/ha, and Rout at 100 kg/ha, but was significantly inferior to the high rate, 200 kg/ha of both CC Tour and Rout, Table 2. For the weeds present in the Pink Oleander pots, Chickweed, Dandelion, Flick Weed and Pink Fumitory, there was no difference in the weed control obtained with any rate of CC Tour or Rout, although all were significantly superior to the untreated pots, Table 3. In summary, Crop Culture Tour Ornamental Herbicide and Rout Ornamental Herbicide were effective in controlling the weeds in pots that contained three ornamental plant species. There was no difference in the level of control when both products were applied at the same rate. Plant Phytotoxicity At each assessment there was no visible effect of the three plant species in either product at all rates compared to the plants in the untreated pots. 28 CONCLUSIONS 1. CC Tour provided effective control of a range of grass and broadleaf weeds present in this trial. 2. CC Tour achieved equivalent levels of weed control to the industry standard, Rout Ornamental Herbicide, when applied at the same rate of product. 3. None of the three plant species, Crepe Myrtle (Lagerstroemia indica), Black Sheoak Casuarina littoralis or Double Rose Pink Oleander (Nerium oleander) showed signs of herbicide phytotoxicity from the application of Crop Culture Tour or Rout Ornamental Herbicide. Assessment Data Black Sheoak 26-Nov-10 134DAT Dandelion Rep 1 2 3 4 total mean 1. Untreated 2.0 3.0 4.0 5.0 14 3.5 2. CC Tour - 50 kg/ha 1.0 0.0 0.0 0.0 1 0.3 3. CC Tour - 100 kg/ha 0.0 1.0 0.0 0.0 1 0.3 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 2.0 2 0.5 5. Rout - 50 kg/ha 2.0 1.0 1.0 0.0 4 1.0 6. Rout - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 7. Rout - 200 kg/ha 0.0 1.0 0.0 0.0 1 0.3 Deadly Nightshade Rep 1 2 3 4 total mean 1. Untreated 1.0 3.0 1.0 3.0 8 2.0 2. CC Tour - 50 kg/ha 0.0 1.0 0.0 1.0 2 0.5 3. CC Tour - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 1.0 0.0 1.0 1.0 3 0.8 6. Rout - 100 kg/ha 0.0 1.0 0.0 0.0 1 0.3 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 29 Flatweed Rep 1 2 3 4 total mean 1. Untreated 1.0 1.0 2.0 3.0 7 1.8 2. CC Tour - 50 kg/ha 1.0 0.0 0.0 0.0 1 0.3 3. CC Tour - 100 kg/ha 1.0 0.0 1.0 0.0 2 0.5 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 0.0 1.0 1.0 1.0 3 0.8 6. Rout - 100 kg/ha 1.0 0.0 1.0 0.0 2 0.5 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Total Weeds Rep 1 2 3 4 total mean 1. Untreated 4.0 7.0 7.0 11.0 29 7.3 2. CC Tour - 50 kg/ha 2.0 1.0 0.0 1.0 4 1.0 3. CC Tour - 100 kg/ha 1.0 1.0 1.0 0.0 3 0.8 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 2.0 2 0.5 5. Rout - 50 kg/ha 3.0 2.0 3.0 2.0 10 2.5 6. Rout - 100 kg/ha 1.0 1.0 2.0 0.0 4 1.0 7. Rout - 200 kg/ha 0.0 1.0 0.0 0.0 1 0.3 Crepe Myrtle T 26-Nov-10 134DAT Chickweed Rep 1 2 3 4 total mean 1. Untreated 1.0 4.0 4.0 1.0 10 2.5 2. CC Tour - 50 kg/ha 1.0 0.0 0.0 1.0 2 0.5 3. CC Tour - 100 kg/ha 0.0 1.0 0.0 0.0 1 0.3 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 1.0 0.0 0.0 2.0 3 0.8 6. Rout - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 7. Rout - 200 kg/ha 0.0 1.0 0.0 0.0 1 0.3 30 Cotula Rep 1 2 3 4 total mean 1. Untreated 5.0 5.0 3.0 1.0 14 3.5 2. CC Tour - 50 kg/ha 2.0 1.0 2.0 2.0 7 1.8 3. CC Tour - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 3.0 1.0 1.0 2.0 7 1.8 6. Rout - 100 kg/ha 0.0 0.0 2.0 0.0 2 0.5 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Dandelion Rep 1 2 3 4 total mean 1. Untreated 1.0 1.0 2.0 3.0 7 1.8 2. CC Tour - 50 kg/ha 1.0 0.0 0.0 0.0 1 0.3 3. CC Tour - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 0.0 1.0 0.0 0.0 1 0.3 6. Rout - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Flick Weed Rep 1 2 3 4 total mean 1. Untreated 4.0 3.0 3.0 0.0 10 2.5 2. CC Tour - 50 kg/ha 0.0 0.0 1.0 0.0 1 0.3 3. CC Tour - 100 kg/ha 0.0 1.0 0.0 0.0 1 0.3 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 1.0 0.0 1.0 0.0 2 0.5 6. Rout - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Total Weeds 31 Rep 1 2 3 4 total mean 1. Untreated 11.0 13.0 12.0 5.0 41 10.3 2. CC Tour - 50 kg/ha 4.0 1.0 3.0 3.0 11 2.8 3. CC Tour - 100 kg/ha 0.0 2.0 1.0 0.0 3 0.8 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 5.0 2.0 2.0 4.0 13 3.3 6. Rout - 100 kg/ha 0.0 0.0 4.0 0.0 4 1.0 7. Rout - 200 kg/ha 0.0 1.0 0.0 0.0 1 0.3 Oleander 26-Nov-10 134DAT Chickweed Rep 1 2 3 4 total mean 1. Untreated 3.0 0.0 4.0 1.0 8 2.0 2. CC Tour - 50 kg/ha 1.0 0.0 0.0 0.0 1 0.3 3. CC Tour - 100 kg/ha 0.0 1.0 0.0 0.0 1 0.3 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 0.0 0.0 0.0 2.0 2 0.5 6. Rout - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 7. Rout - 200 kg/ha 0.0 1.0 0.0 0.0 1 0.3 Dandelion Rep 1 2 3 4 total mean 1. Untreated 1.0 3.0 1.0 1.0 6 1.5 2. CC Tour - 50 kg/ha 0.0 0.0 0.0 0.0 0 0.0 3. CC Tour - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 0.0 0.0 1.0 0.0 1 0.3 6. Rout - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Flick Weed Rep 1 2 3 4 total mean 32 1. Untreated 1.0 2.0 3.0 0.0 6 1.5 2. CC Tour - 50 kg/ha 1.0 0.0 0.0 0.0 1 0.3 3. CC Tour - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 0.0 1.0 0.0 0.0 1 0.3 6. Rout - 100 kg/ha 0.0 0.0 1.0 0.0 1 0.3 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Fumitory, Pink Rep 1 2 3 4 total mean 1. Untreated 4.0 3.0 2.0 1.0 10 2.5 2. CC Tour - 50 kg/ha 0.0 0.0 0.0 0.0 0 0.0 3. CC Tour - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 1.0 0.0 1.0 0.0 2 0.5 6. Rout - 100 kg/ha 0.0 0.0 0.0 0.0 0 0.0 7. Rout - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 Total Weeds Rep 1 2 3 4 total mean 1. Untreated 9.0 8.0 10.0 3.0 30 7.5 2. CC Tour - 50 kg/ha 2.0 0.0 0.0 0.0 2 0.5 3. CC Tour - 100 kg/ha 0.0 1.0 1.0 0.0 2 0.5 4. CC Tour - 200 kg/ha 0.0 0.0 0.0 0.0 0 0.0 5. Rout - 50 kg/ha 1.0 1.0 2.0 2.0 6 1.5 6. Rout - 100 kg/ha 0.0 0.0 2.0 0.0 2 0.5 7. Rout - 200 kg/ha 0.0 1.0 0.0 0.0 1 0.3 Example 7 The following granule compositions of the invention were prepared using polyethylene glycols as the water-miscible carrier liquid. 33 Granule (a) Component Concentration (g/kg) Oxyfluorfen (96%) 21.05 Oryzalin (95%) 10.53 PEG 200 100 Attapulgite 868.42 TOTAL 1000 Granule (b) Component Concentration (g/kg) Oxyfluorfen (96%) 21.05 Oryzalin (95%) 10.53 PEG 300 100 Attapulgite 868.42 TOTAL 1000 Granule (c) Component Concentration (g/kg) Oxyfluorfen (96%) 21.05 Oryzalin (95%) 10.53 PEG 600 100 Attapulgite 868.42 TOTAL 1000 Granule (d) Component Concentration (g/kg) Oxyfluorfen (96%) 21.05 Oryzalin (95%) 10.53 PEG 200 70 PEG 600 70 Attapulgite 828.42 TOTAL 1000 Results: Formulation number Results Liquid Concentrate a Dull yellow granule Recrystallizes at room temp. b Dull yellow granule Recrystallizes at room temp. c Yellow granule Recrystallizes at room temp. d Dull yellow granule Partial re-crystallization at room temp. Slow process. Over time granules a to d were found to form fine dust material which makes these compositions less suited to long term storage and handling than the composition of Example 3. 34

Claims

1. A herbicidal broadcast granule comprising at least one of oxyfluorfen and oryzalin in solid form in an amount of no more than 8% by weight oxyfluorfen and no more than 8% by weight oryzalin based on the total granule, a water miscible carrier liquid in which the at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 8% w/w at a temperature of 600C and a carrier granule which is not an agglomeration of powder, wherein the carrier granule has a particle size in the range of 0.2 to 4mm in which a mixture of the at least one of oxyfluorfen and oryzalin and water miscible liquid carrier is absorbed.

2. A herbicidal broadcast granule according to claim 1 comprising oxyfluorfen in solid form in an amount of up to 8% by weight/weight oxyfluorfen based on the total granule weight and a water-miscible carrier liquid in which oxyfluorfen is soluble in an amount of at least 8% weight/weight at a temperature of 600C.

3. A herbicidal broadcast granule according to claim 1 or claim 2, wherein at least part of the oxyfluorfen and/or oryzalin is in the form of a precipitate.

4. A herbicidal granule according to claim 1 or claim 2, wherein oxyfluorfen is present in an amount of from 0.5 % w/w to 5 % w/w of the granule composition and oryzalin is present in an amount of from 0.5 % w/w to 4 % w/w of the granule composition.

5. A herbicidal broadcast granule according to any one of claims 1 to 3, wherein the water-miscible carrier liquid comprises water-miscible organic compound and water in a volume/volume ratio of water-miscible organic compound to water in the range of from 10:1 to 1:1.

6. A herbicidal broadcast granule according to any one of the previous claims wherein the carrier granule is a clay selected from attapulgite, bentonite and mixtures thereof. 35

7. A herbicidal broadcast granule according to any one of the previous claims comprising a hydrophilic tackifying macromolecule selected from the group consisting of polyvinyl pyrrolidine, cellulosic polymers and polyethylene glycols.

8. A herbicidal broadcast granule according to any one of the previous claims, wherein the oxyfluorfen has a solubility in the water-miscible carrier liquid of no more than 10% by weight/weight at 200C.

9. A herbicidal broadcast granule according to any one of the previous claims, wherein the water-miscible carrier liquid is present in an amount of from 2% to 15% by weight based on the total weight of the granule composition.

10. A herbicidal broadcast granule according to any one of the previous claims, wherein the water-miscible carrier liquid comprises a water-miscible organic compound selected from the group consisting of glycol ethers and polyalkylene glycols.

11. A herbicidal broadcast granule according to claim 9, wherein the water-miscible organic compound is selected from the group consisting of mono-(C 1 to C6 alkyl)ethers of di- or tri-(C 2 to C4 alkylene)glycols and polyethylene glycols.

12. A herbicidal broadcast granule according to claim 5, wherein the weight ratio of hydrophilic tackifying agent to water-miscible carrier liquid is in a weight by weight ratio in the range of 0.03 to 0.15.

13. A method of forming a herbicidal broadcast granule comprising at least one of oxyfluorfen and oryzalin in crystalline solid form in an amount of no more than 8% by weight oxyfluorfen and no more than 8% oryzalin based on the total granule weight, the method comprising: providing a solution of at least one of oxyfluorfen and oryzalin in a water miscible carrier liquid at an elevated temperature of at least 400C, in which said at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 8% 36 by weight at a temperature of 600C based on the weight of water-miscible carrier liquid; wherein the water-miscible carrier liquid comprises a water-miscible organic compound and water in an amount of at least 10% on a weight by weight basis of the water-miscible carrier liquid; and applying the solution at an elevated temperature to absorbent carrier granules of size in the range of from 0.2mm to 4mm to provide active herbicide loaded granules having a loading of at least one of oxyfluorfen and oryzalin of up to 8% by weight of the total weight of loaded granules; and cooling the granules to precipitate at least one of oxyfluorfen and oryzalin within the granules.

14. The method according to claim 13, wherein the elevated temperature is at least 500C and wherein said at least one of oxyfluorfen and oryzalin is soluble in an amount of at least 15% by weight at a temperature 600C based on the weight of water-miscible carrier liquid.

15. A method of forming an oxyfluorfen broadcast granule comprising oxyfluorfen in crystalline solid form in an amount up to 8% by weight oxyfluorfen based on the total granule weight, the method comprising: providing a solution of oxyfluorfen in a water-miscible carrier liquid at an elevated temperature of at least 500C, in which oxyfluorfen is soluble in an amount of at least 25% by weight oxyfluorfen at a temperature of 600C based on the weight of water-miscible carrier liquid; and wherein the water-miscible carrier liquid comprises a water-miscible organic compound and water in an amount of at least 10% on a weight by weight basis of the water-miscible carrier liquid; and wherein the solubility of oxyfluorfen in the water-miscible carrier liquid is no more than 10% w/w at 200C by weight oxyfluorfen based on the weight of the water miscible carrier liquid; and applying the solution at an elevated temperature of at least 500C to carrier granules to provide active loaded granules having a loading of 37 oxyfluorfen of up to 8% oxyfluorfen by weight of the total active loaded granules absorbed into the granules; and cooling the granules to precipitate oxyfluorfen within the granules.

16. A method of according to any one of claims 13 to 15, wherein the water miscible carrier liquid comprises volume/volume ratio of water-miscible organic compound to water in the range of from 10:1 to 1:1 and wherein the water miscible organic compound is used in a ratio with water in which it is miscible at the temperature at which the solution is applied.

17. A method according to any one of claims 13 to 16, wherein the water-miscible organic compound is selected from the group consisting of C1 to C6 alkyl mono ethers of di and tri C2 to C4 alkylene glycols and polyethylene glycols.

18. A method according to claim 17, wherein the water-miscible organic compound is selected from the group consisting of diethylene glycol mono alkyl ethers and triethylene glycol mono alkyl ethers wherein the alkyl is selected from methyl, ethyl, propyl and butyl and polyethylene glycols of molecular weight 200 to 10,000.

19. A method according to any one of claims 13 to 18, wherein the solution applied to the granular composition comprises in the range of from 10% to 40% by weight oxyfluorfen.

20. A method according to any one of claims 13 to 19, wherein the solution applied to the granular composition comprises oryzalin in an amount in the range of from 5%w/w to 20% w/w.

21. A method according to any one of claims 13 to 20, wherein the solution further comprises a hydrophilic polymer selected from the group consisting of cellulose polymers polyvinyl pyrolidone and polyethylene glycols. 38

22. A method according to any one of claims 13 to 21, wherein the solution comprises oryzalin in an amount of from 0.5% w/w to 4% w/w of the granule composition.

23. A method according to any one of claims 13 to 22, applied to granules in a rotatable drum by pouring the solution on to granules in the drum and rotating the drum to distribute the liquid among the granules.

24. A method according to any one of claims 12 to 23, wherein the granules combined with the solution are formed of clay selected from the group consisting of attapulgite, bentonite and mixtures thereof. 39