WO2004080178A1

WO2004080178A1 - Herbicidal suspoemulsion

Info

Publication number: WO2004080178A1
Application number: PCT/EP2004/001377
Authority: WO
Inventors: Sarah Beth Cush; Michael James Hopkinson
Original assignee: Syngenta Participations Ag
Priority date: 2003-03-12
Filing date: 2004-02-13
Publication date: 2004-09-23
Also published as: US20060183643A1; BRPI0409577A; ZA200506300B; GT200400025A; CA2517220C; EP1603388B1; MXPA05009525A; CL2004000475A1; AR043424A1; GB0305679D0; RS20050696A; PL377721A1; SI1603388T1; EP1603388A1; UA81945C2; RS53004B; PT1603388E; US20140121105A1; DE602004006500T2; CA2517220A1

Abstract

A suspoemulsion formulation comprising: (a) a continuous phase comprising: (i) one or more block co-polymers, and (ii) one or more non-ionic surfactants; (b) a dispersed emulsion phase comprising: (i) a chloroacetamide, and (ii) a polymeric stabiliser; and (c) a dispersed solid phase comprising: (i) a 2-(substituted benzoyl)-1,3-cyclohexanedione herbicide; and (ii) a stabilising metal salt.

Description

HERBICIDAL SUSPOEMULSION

The present invention relates to a novel agrochemical formulation comprising at least two active ingredients and the use thereof.

Agricultural pesticide manufacturers have identified the need for broad-spectrum pesticidal products. Single active ingredient formulations rarely meet such broad- spectrum requirements, and thus combination products, perhaps containing up to four complementary biologically active ingredients, have been developed. Such products have several additional advantages e.g. elimination of tank mixing; reduction in inventory products; saving in time and money; and a reduction in the number of times the crop is sprayed.

The development of such products is relatively simple providing that the active ingredients to be combined are physically, chemically and biologically compatible. In these situations the active ingredients can be combined in a broad range of formulation types well known in the art. Where the active ingredients are not physically, chemically and/or biologically compatible, it has been necessary to develop novel formulations to overcome the problems associated with such incompatibilities. One example of a formulation type is the so-called 'suspoemulsion' formulation. These suspoemulsion formulations are formed by combining an emulsion phase, containing one or more active ingredients, with a continuous phase also contaimng one or more active ingredients in the form of a solid dispersion. This type of formulation has several user advantages related to ease of transportation, storage and field application.

However, the formation of such suspoemulsion formulations is rarely straightforward. The technical challenge and complexity to formulate suspoemulsion formulations with satisfactory physical and chemical stability has been previously reported (e.g. Suspoemulsion Technology and Trends, Joseph R. Winkle, Pesticide Formulation and Adjuvant Technology, CRC Press, 1996).

Particular problems were encountered when attempting to formulate the active ingredients of the present invention into a suspoemulsion. One of the preferred active ingredients used is mesotrione (2-(2'-nitro-4'-methylsulphonylbenzoyl)-l,3- cyclohexanedione), which may be present either as the free acid, or as a metal salt. Mesotrione free acid is chemically unstable in aqueous medium under a range of pH conditions and/or concentration. The problem of the chemical instability may be overcome by chelating the mesotrione free acid with a metal chelating agent, for example a copper or zinc salt. However, the introduction of the metal salt into the composition surprisingly led to severe complications with the physical stability of the resulting suspoemulsion. It was noted that the chelated mesotrione particles were migrating into the emulsion phase - a phenomenon known as heteroflocculation/coagulation. Depending on the surfactant system, this heteroflocculation/coagulation could happen instantaneously on a macroscopic scale or very slowly, only under stress at a microscopic scale. This was considered very abnormal behaviour as it appeared that the event was not just a fiocculation (surface to surface) event, but rather an actual migration of the mesotrione to the inside of the emulsion droplet. It is therefore an object of the present invention to provide a chemically and physically stable suspoemulsion formulation that comprises a 2-(substituted benzoyl)- 1,3-cyclohexanedione herbicide as one of the active ingredients.

Accordingly, a first aspect of the invention provides a suspoemulsion formulation comprising: (a) a continuous phase comprising

(i) one or more block co-polymers, and (ii) one or more non-ionic surfactants;

(b) a dispersed emulsion phase comprising (i) a chloroacetamide, and (ii) a polymeric stabiliser; and

(c) a dispersed solid phase comprising

(i) a 2-(substituted benzoyl)- 1 ,3-cyclohexanedione herbicide; and (ii) a stabilising metal salt. The suspoemulsion formulation of the present invention may optionally further comprise one or more additional active ingredients. The one or more additional active ingredients may be a pesticide, for example a herbicide, fungicide, insecticide or the like; or the additional active ingredient may be a compound selected from the class of compounds known as safeners or antidotes. The concentration of additional active ingredient in the formulation is suitably in the range of from 1 g/1 to 500 g/1, and preferably from 2 g/1 to 300g/l.

In one preferred embodiment, the suspoemulsion formulation further comprises an additional active ingredient which is a herbicide, for example a herbicide selected from the class known as triazines, for example atrazine or terbuthylazine; a phosphonate herbicide, for example glyphosate or salts thereof; or a phosphinate herbicide, such as glufosinate or salts thereof. The concentration of additional herbicide is suitably in the range of from 5 g/1 to 500 g/1, and preferably from 10 g/1 to 300 g/1. Most preferably, the additional herbicide is a triazine, preferably atrazine or terbuthylazine. Suitably, the additional herbicide is present in the dispersed solid phase of the suspoemulsion. In a second preferred embodiment, the suspoemulsion formulation further comprises an additional active ingredient selected from the class of compounds known as safeners or antidotes, for example benoxacor. The concentration of safener is suitably in the range of from 1 g/1 to 100 g/1, and preferably from 2 g/1 to 40 g/1. Suitably, the safener is present in the dispersed emulsion phase of the suspoemulsion. In a third preferred embodiment, the suspoemulsion formulation further comprises at least two additional active ingredients, wherein at least one of the additional active ingredients is a herbicide, for example a triazine, such as atrazine or terbuthylazine, and at least one of the other additional active ingredients is a safener, for example benoxacor. The continuous phase may be any suitable solvent, for example water, glycol or alcohol, but is preferably water.

Examples of suitable block copolymers that may be used in the present invention (in either the dispersed solid phase or the dispersed emulsion phase) include alkyleneoxide copolymers (such as ethylene oxide-propylene oxide block copolymers, ethylene oxide-butylene oxide block copolymers), C_2-6 alkyl adducts of ethylene oxide- propylene oxide block copolymers, C _-6 alkyl adducts of ethylene oxide-butylene oxide block copolymers, polyoxyethylene-polyoxypropylene monoalkylethers such as butyl ether, methyl ether, propyl ether, ethyl ether, or mixtures thereof. Additional examples of block copolymers and their availability will be well known to those in the art. Suitably, the concentration of block copolymer in the suspoemulsion formulation of the invention is from 0.1 to 10.0%, and preferably from 0.2 to 7.0%.

Examples of non-ionic surfactants that may be used in the present invention will be known to those skilled in the art, and include but art not limited to EO-PO block copolymers, butoxy block copolymes, graft comb polymers, polyethylene glycol mono and diesters, polyglyceryl alcohol ethers, alkyl ethoxylates, tristyryl ethoxylates, alkyl aryl ethoxylates and alkylpolyglycosides. Suitably, the concentration of non-ionic surfactant in the suspoemulsion formulation of the invention is from 0.2 to 15.0%, and preferably from 0.5 to 10.0%. Examples of the chloroacetamide suitable for use in the present invention include compounds of formula (I)

wherein R¹ is hydrogen, methyl or ethyl; R² is hydrogen or ethyl; R³ is hydrogen or methyl; and R⁴ is methyl, methoxy, methoxymethyl, ethoxy, or butoxy. Suitably, the chloroacetamide is selected from the group consisting of metolachlor, acetochlor and alachlor, preferably metolachlor, and most preferably, s-metolachlor. Suitably, the concentration of chloroacetamide in the suspoemulsion formulation is from 100 to 750 g/1, more suitably from 250 to 500 g/1. Examples of suitable polymeric stabilizers that may be used in the present invention have a molecular weight between 10,000 and 1,000,000 daltons and include, but are not limited to polypropylene, polyisobutylene, polyisoprene, copolymers of monoolefins and diolefins, polyacrylates, polystyrene, polyvinyl acetate, polyurethanes or polyamides. Suitably, the concentration of polymeric stabilizer in the suspoemulsion formulation of the invention is from 0.1 to 7.0%, and preferably from 0.2 to 4.0%.

Suitably, the 2-(substituted benzoyl)-l,3-cyclohexanedione for use in the present invention is a compound of formula (II)

wherein X represents a halogen atom; a straight- or branched-chain alkyl or alkoxy group containing up to six carbon atoms which is optionally substituted by one or more groups -OR⁵ or one or more halogen atoms; or a group selected from nitro, cyano, -

CO₂R⁶ , -S(O)_mR⁵, -O(CH₂)_rOR⁵, -COR⁵, -NR⁶R⁷, -SO₂NR⁶R⁷, -CONR⁶R⁷, -CSNR⁶R⁷ and -OSO₂R⁸;

R⁵ represents a straight- or branched-chain alkyl group containing up to six carbon atoms which is optionally substituted by one or more halogen atoms; R⁶ and R⁷ each independently represents a hydrogen atom; or a straight- or branched-chain alkyl group containing up to six carbon atoms which is optionally substituted by one or more halogen atoms;

R⁸ represents a straight-or branched-chain alkyl, alkenyl or alkynyl group containing up to six carbon atoms optionally substituted by one or more halogen atoms; or a cycloalkyl group containing from three to six carbon atoms; each Z independently represents halo, nitro, cyano, S(O)_mR⁹, OS(O)_mR⁹, C_1-6 alkyl, C_1-6 alkoxy, C_1-6 haloalkyl, C_1-6 haloalkoxy, carboxy, C_1-6 alkylcarbonyloxy, C_1-6 alkoxycarbonyl, C_1-6 alkylcarbonyl, amino, C.-e alkylamino, C_1-6 dialkylamino having independently the stated number of carbon atoms in each alkyl group, C_1-6 alkylcarbonylarnino, C_1-6 alkoxycarbonylamino, C_1-6 alkylaminocarbonylamino, C_1-6 dialkylaminocarbonylamino having independently the stated number of carbon atoms in each alkyl group, C_1-6 alkoxycarbonyloxy, C_1-6 allsylaminocarbonyloxy, Cι_-6 dialkylcarbonyloxy, phenylcarbonyl, substituted phenylcarbonyl, phenylcarbonyloxy, substituted phenylcarbonyloxy, phenylcarbonylamino, substituted phenylcarbonylamino, phenoxy or substituted phenoxy;

R⁹ represents cyano, -COR¹⁰, -CO₂R¹⁰ or-S(O)mR^π;

R¹⁰ represents hydrogen or straight- or branched-chain alkyl group containing up to six carbon atoms; R¹¹ represents C_1-6 alkyl, C_1-6 haloalkyl, C_1-6 cyanoalkyl, C _-8 cycloalkyl optionally substituted with halogen, cyano or C_1-4 alkyl; or phenyl optionally substituted with one to three of the same or different halogen, nitro, cyano, C _-4 haloalkyl, C - alkyl,

alkoxy or-S(O)_mR¹²;

R represents C_1- alkyl; each Q independently represents C_1-4 alkyl or -CO₂R¹³ wherein R¹³ is C_1- alkyl; m is zero, one or two; n is zero or an integer from one to four; r is one, two or three; and p is zero or an integer from one to six. Suitably, X is chloro, bromo, nitro, cyano, C₁-₄ alkyl, -CF₃, -S(O)mR⁵, or -OR⁵; each Z is independently chloro, bromo, nitro, cyano, C_1- alkyl, -CF₃, -OR⁵, -OS(O)_mR⁹ or -S(O)mR⁹; n is one or two; and p is zero.

Preferably, the 2-(substituted benzoyl)-l,3-cyclohexanedione of formula (II) is selected from the group consisting of 2-(2'-nitro-4'-methylsulphonylbenzoyl)-l ,3- cyclohexanedione, 2-(2'-nitro-4'-methylsulphonyloxybenzoyl)-l,3-cyclohexanedione, 2- (2'-chloro-4'-methylsulphonylbenzoyl)-l,3-cyclohexanedione, 4,4-dimethyl-2-(4- methanesulphonyl-2-nitrobenzoyl)-l,3-cyclohexanedione, 2-(2-chloro-3-ethoxy-4- methanesulphonylbenzoyl)-5-methyl- 1 ,3-cyclohexanedione and 2-(2-chloro-3-ethoxy-4- ethanesulphonylbenzoyl)-5-methyl-l,3-cyclohexanedione; most preferably is 2-(2'-nitro- 4'-methylsulphonyl benzoyl)-l ,3-cyclohexanedione.

Suitably, the concentration of the 2-(substituted benzoyl)-l,3-cyclohexanedione in the suspoemulsion formulation of the present invention is fromlO to 100 g/1, more suitably 25 to 60 g/1. Examples of suitable stabilizing metal salts that may be used include calcium, beryllium, barium, titanium, magnesium, manganese, zinc, iron, cobalt, nickel and copper salts; most suitable are magnesium, manganese, zinc, iron, cobalt, nickel and copper salts; especially preferred is a copper salt, for example copper hydroxide. Suitably, the concentration of stabilizing metal salts in the suspoemulsion formulation of the invention is from 0.01 to 4.0%, and preferably from 0.02 to 1.5%.

In a further aspect of the invention, there is provided a method for controlling the growth of undesirable vegetation such as weeds, which may be present around the locus of a desired plant species (which may or may not exhibit resistance, either by natural means or by genetic modification, to one or more herbicides), e.g. a crop such as corn, which comprises applying the formulation of the invention to the locus of such undesirable vegetation. Alternatively, in a further aspect of the invention, there is provided the use of the formulation of the invention for the control of undesirable vegetation. Examples of undesirable vegetation include, but are not limited to, velvetleaf, redroot pigweed, common water hemp, Palmer amaranth, ivyleaf morning glory, prickly sida, giant ragweed, common ragweed, common cocklebur, Eastern black nightshade, common lambsquarters, Pennsylvania smartweed, common sunflower, jimsonweed, hemp sesbania, toothed spurge, common purslane, large crabgrass, yellow foxtail and kochia. The weeds may or may not demonstrate resistance (either naturally or genetically modification) to one or more herbicides. The suspoemulsion formulation may be applied pre-emergence or post-emergence of the crop. Preferably, the formulation is applied pre- emergent. The formulation may be applied by air or on the ground by known techniques, such as hydraulic nozzle spray.

One advantage of the suspoemulsion formulation of the present invention is that, under the majority of conditions, season-long control of weeds is obtained by just one application of the formulation.

The present invention will now be described by way of example only.

EXAMPLE 1 1.1 Preparation of Premixes

1.1.1 Preparation of S-metolachlor EW

% wt

S-metolachlor 66.67

A herbicidal antidote such as benoxacor 3.33

A polymer such as polystyrene 4.18

A block copolymer such as

Pluronic P65 2.13

Silicone antifoaming agent 0.18

Water 23.51

The polystyrene and benoxacor are dissolved in the s-Metolachlor. The Pluronic P65 is dissolved in the aqueous phase and the antifoam is added. The two are combined in such a way as to form an emulsified organic phase with a particle size of 1 - 40 microns.

1.1.2 Preparation of Mesotrione Millbase

% wt Mesotrione 35.00

A non-ionic surfactant such as Tristyryl phenol with 16 moles of EO 2.89

Acetic acid (56%) 11.01

Copper hydroxide (100%) 3.50

Silicone antifoaming agent 0.10

Xanthan gum 0.10 Water 47.40

Mix together the water, acetic acid and copper hydroxide. Add the mesotrione. The non-ionic surfactant, antifoaming agent, and xanthan gum are added and mixed until uniform. Mill until the median particle size is 1- 6 microns.

1.2 Preparation of Final Product

% wt

S-Metolachlor EW 55.20

Mesotrione millbase 10.50

Ethylene glycol 3.00

A non-ionic surfactant such as a Cg-Cπ alkylpolyglycoside 6.00

A block copolymer such as a butyl PO/EO surfactant 5.00

Xanthan gum 0.16

A preservative such as benzoisothiazolinone 0.15

Water rest

Blend together the s-Metolachlor EW, propylene glycol, the non-ionic surfactant, the block copolymer and some of the water. Add the mesotrione millbase and blend. Add the xanthan gum and preservative and blend until uniform. Assay and trim with water if needed.

EXAMPLE 2 2.1 Preparation of Premixes

2.1.1 Preparation of S-metolachlor EW

% wt S-metolachlor 66.67

A herbicidal antidote such as benoxacor 3.33

A polymer such as polystyrene 3.68

A block copolymer such as

Pluronic FI 08 1.00 Silicone antifoaming agent 0.18

Water 25.14

The polystyrene and benoxacor are dissolved in the s-Metolachlor. The Pluronic F 108 is dissolved in the aqueous phase and the antifoam is added. The two are combined in such a way as to form an emulsified organic phase with a particle size of 1 — 40 microns. 2.1.2 Preparation of Mesotrione Millbase

% wt

Mesotrione 35.00

A non-ionic surfactant such as

Tristyryl phenol with 25 moles of EO 3.50

Acetic acid (56%) 11.01

Copper hydroxide (100%) 5.00

Silicone antifoaming agent 0.10

Xanthan gum 0.10

Water 45.29

2.2 Preparation of Final Product

% wt

S-Metolachlor EW 55.20

Mesotrione millbase 10.50

Propylene glycol 3.00

A non-ionic surfactant such as a C₉-Cπ alkylpolyglycoside 5.00

A block copolymer such as a butyl PO EO surfactant 6.00

Xanthan gum 0.16

A preservative such as benzoisothiazolinone 0.15

Water rest Blend together the s-Metolachlor EW, propylene glycol, the non-ionic surfactant, the block copolymer and some of the water. Add the mesotrione millbase and blend. Add the xanthan gum and preservative and blend until uniform. Assay and trim with water if needed.

EXAMPLE 3

3.1 Preparation of Premixes

3.1.1 Preparation of S-metolachlor EW

% wt S-metolachlor 66.67

A herbicidal antidote such as benoxacor 3.33

A polymer such as polystyrene 2.12 A block copolymer such as

Pluronic F68 1.50

Silicone antifoaming agent 0.18

Water 26.20

The polystyrene and benoxacor are dissolved in the s-Metolachlor. The Pluronic F68 is dissolved in the aqueous phase and the antifoam is added. The two are combined in such a way as to form an emulsified organic phase with a particle size of 1 - 40 microns.

3.1.2 Preparation of Mesotrione Millbase

% wt Mesotrione 35.00

A non-ionic surfactant such as

Tristyryl phenol with 40 moles of EO 2.89 Acetic acid (56%) 11.01

Copper hydroxide (100%) 5.00 Silicone antifoaming agent 0.10

Xanthan gum 0.10

Water 45.90

Mix together the water, acetic acid and copper hydroxide. Add the mesotrione. The non-ionic surfactant, antifoaming agent, and xanthan gum are added and mixed until uniform. Mill until the median particle size is 1- 6 microns. 3.2 Preparation of Final Product

% wt

S-Metolachlor EW 55.20

Mesotrione millbase 10.50

Glycerin 3.00

A non-ionic surfactant such as a C₉-C11 alkylpolyglycoside 7.00

A block copolymer such as a butyl PO/EO surfactant 3.00

Xanthan gum 0.16

A preservative such as benzoisothiazolinone 0.15

Water rest

EXAMPLE 4

4.1 Preparation of Premixes

4.1.1 s-Metolachlor EW (see 3.1.1

4.1.2 Atrazine Millbase % wt

Atrazine Technical (100%) 57.80

A non-ionic surfactant such as an alkyl ethoxylate with 4 to 8 moles of EO 0.58 An EO PO/EO block copolymer such as Pluronic P38 1.56

Glycerine 4.50

Silicone antifoaming agent 0.12

Xanthan gum 0.05

A preservative such as benzoisothiazolinone 0.05

Water rest

Mix together the surfactants, ethylene glycol and water until uniform. Add antifoaming agent and Atrazine and mix. Grind slurry to a particle size of 95% less than 17 microns. Add the xanthan gum and preservative and mix until homogeneous. 4.1.3 Preparation of Mesotrione Millbase (see 3.1.2) 4.2 Preparation of Final Formulation

% wt s-Metolachlor EW 44.1

Glycerin 4.00

A non-ionic surfactant such as a C₉-C11 alkylpolyglycoside 4.50

A block copolymer such as a butyl PO/EO surfactant 4.50

Mesotrione Millbase 8.4

Atrazine Basemix 19.0

Xanthan gum 0.9

A preservative such as

Benzoisothiazolinone 0.9

Water rest

Blend together the s-Metolachlor EW, water, propylene glycol and surfactants until uniform. Add the mesotrione millbase and mix. Add the Atrazine Basemix followed by the xanthan gum and preservative and mix until uniform.

EXAMPLE 5

5.1 Preparation of Premixes 5.1.1 Preparation of S-metolachlor EW (see 2.1.1) 5.1.2 Atrazine Millbase

% wt Atrazine Technical (100%) 57.80

A non-ionic surfactant such as an alkyl ethoxylate with 4 to 8 moles of EO 1.15 An EO/PO/EO block copolymer such as

Pluronic P65 0.70

Ethylene Glycol 3.00

Silicone antifoaming agent 0.12 Xanthan gum 0.05

A preservative such as benzoisothiazolinone 0.05

Water rest

Mix together the surfactants, ethylene glycol and water until uniform. Add antifoaming agent and Atrazine and mix. Grind slurry to a particle size of

95% less than 17 microns. Add the xanthan gum and preservative and mix until homogeneous. 5.1.3 Preparation of Mesotrione Millbase (see 2.1.2) 5.2 Preparation of Final Formulation

% wt s-Metolachlor EW 44.1

Propylene glycol 5.00

A non-ionic surfactant such as a C₉-Cn alkylpolyglycoside 4.00

A block copolymer such as a butyl PO/EO surfactant 5.00

Mesotrione Millbase 8.4

Atrazine Basemix 19.0

Xanthan gum 0.9

A preservative such as

Benzoisothiazolinone 0.9

Water rest

Blend together the s-Metolachlor EW, water, propylene glycol and surfactants until uniform. Add the mesotrione millbase and mix. Add the Atrazine Basemix followed by the xanthan gum and preservative and mix until uniform. EXAMPLE 6

6.1 Preparation of Premixes

6.1.1 s-Metolachlor EW (see 3.1.1)

6.1.2 Atrazine Millbase % wt

Atrazine Technical (100%) 57.80

A non-ionic surfactant such as an alkyl ethoxylate with 4 to 8 moles of EO 1.69 An EO/PO/EO block copolymer such as Pluronic P38 0.40

Ethylene Glycol 3.00

Silicone antifoaming agent 0.12

Xanthan gum 0.05

A preservative such as benzoisothiazoUnone 0.05

Water rest

Mix together the surfactants, ethylene glycol and water until uniform. Add antifoaming agent and Atrazine and mix. Grind slurry to a particle size of 95% less than 17 microns. Add the xanthan gum and preservative and mix until homogeneous.

6.1.3. Preparation of Mesotrione Millbase (see 1.1.2) 6.2 Preparation of Final Formulation

% wt s-Metolachlor EW 44.1 Glycerin 5.00

A non-ionic surfactant such as a Cg-Cπ alkylpolyglycoside 3.00

A block copolymer such as a butyl PO/EO surfactant 6.00 Mesotrione Millbase 8.4

Atrazine Basemix 19.0

Xanthan gum 0.9

A preservative such as

Benzoisothiazolinone 0.9 Water rest

Blend together the sMetolachlor EW, water, propylene glycol and surfactants until uniform. Add the mesotrione millbase and mix. Add the Atrazine Basemix followed by the xanthan gum and preservative and mix until uniform.

EXAMPLE 7

7.1 Preparation of Premixes

7.1.1 Metolachlor EW % wt

Metolachlor 66.67

A herbicidal antidote such as benoxacor 3.33

A polymer such as polystyrene 4.18

A block copolymer such as

Pluronic FI 08 1.87

Silicone antifoaming agent 0.18

Water 23.77 The polystyrene and benoxacor are dissolved in the Metolachlor.

The Pluronic F108 is dissolved in the aqueous phase and the antifoam is added. The two are combmed in such a way as to form an emulsified organic phase with a particle size of 1 — 40 microns.

7.1.2 Atrazine Millbase (see 6.1.2) 7.1.3 Preparation of Mesotrione Millbase (see 1.1.2)

7.2 Preparation of Final Formulation

% wt

Metolachlor EW 44.1

Glycerin 5.00 A non-ionic surfactant such as a C₉-Cπ alkylpolyglycoside 3.00 A block copolymer such as a butyl PO/EO surfactant 6.00

Mesotrione Millbase 8.4 Atrazine Basemix 19.0

Xanthan gum 0.9

A preservative such as

Benzoisothiazolinone 0.9 Water rest

Blend together the Metolachlor EW, water, propylene glycol and surfactants until uniform. Add the mesotrione millbase and mix. Add the Atrazine Basemix followed by the xanthan gum and preservative and mix until uniform.

Claims

CLA S

1. A suspoemulsion formulation comprising:

(a) a continuous phase comprising

(i) one or more block co-polymers, and (ii) one or more non-ionic surfactants;

(b) a dispersed emulsion phase comprising (i) a chloroacetamide, and

(ii) a polymeric stabiliser; and

(c) a dispersed solid phase comprising (i) a 2-(substituted benzoyl)-l,3-cyclohexanedione herbicide; and

(ii) a stabilising metal salt.

2. A suspoemulsion formulation according to claim 1, which further comprises one or more additional active ingredients.

3. A suspoemulsion formulation according to claim 2, wherein the additional active ingredient is a herbicide.

4. A suspoemulsion formulation according to claim 2, wherein the additional active ingredient is a safener or antidote compound.

5. A suspoemulsion formulation according to claim 2, wherein the additional active ingredient comprises a herbicide and a safener or antidote compound.

6. A suspoemulsion formulation according to any one of claims 1 to 5, wherein the continuous phase is selected from the groups consisting of water, glycol or alcohol.

7. A suspoemulsion formulation according to claim 6, wherein the continuous phase is water.

8. A suspoemulsion formulation according to any one of claims 1 to 7, wherein the chloroacetamide is a compound of formula (I)

wherein R¹ is hydrogen, methyl or ethyl; R² is hydrogen or ethyl; R³ is hydrogen or methyl; and R⁴ is methyl, methoxy, methoxymethyl, ethoxy, or butoxy.

9. A suspoemulsion formulation according to claim 8, wherein the chloroacetamide is selected from the group consisting of metolachlor, acetochlor and alachlor.

10. A suspoemulsion formulation according to claim 9, wherein the chloroacetamide is s-metolachlor.

11. A suspoemulsion formulation according to any one of claim 1 to 10, wherein the 2-(substituted benzoyl)-l,3-cyclohexanedione compound is a compound of formula (LT)

CO₂R⁶ , -S(O)_mR⁵, -O(CH₂)_rOR⁵, -COR⁶, -NR⁶R⁷, -SO₂NR⁶R⁷, -CO R⁶R⁷, -CSNR⁶R⁷ and -OSO₂R⁸;

R⁵ represents a straight- or branched-chain alkyl group containing up to six carbon atoms which is optionally substituted by one or more halogen atoms;

R and R each independently represents a hydrogen atom; or a straight- or branched-chain alkyl group containing up to six carbon atoms which is optionally substituted by one or more halogen atoms;

R⁸ represents a straight-or branched-chain alkyl, alkenyl or alkynyl group containing up to six carbon atoms optionally substituted by one or more halogen atoms; or a cycloalkyl group containing from three to six carbon atoms; each Z independently represents halo, nitro, cyano, S(O)_mR⁹, OS(O)_mR⁹, C_1-6 alkyl, C_1-6 alkoxy, d-₆ haloalkyl, C_1-6haloalkoxy, carboxy, C_1-6 alkylcarbonyloxy, C_1-6 alkoxycarbonyl, C_1-6 alkylcarbonyl, amino, C_1-6 alkylamino, C_1-6dialkylamino having independently the stated number of carbon atoms in each alkyl group, C_1-6 alkylcarbonylamino, C_1-6 alkoxycarbonylamino, C_1-6 alkylaminocarbonylamino, Cι_₆ dialkylaminocarbonylamino having independently the stated number of carbon atoms in each alkyl group, C_1-6 alkoxycarbonyloxy, C_1-6 alkylaminocarbonyloxy, C_1-6 dialkylcarbonyloxy, phenylcarbonyl, substituted phenylcarbonyl, phenylcarbonyloxy, substituted phenylcarbonyloxy, phenylcarbonylamino, substituted phenylcarbonylamino, phenoxy or substituted phenoxy;

R⁹ represents cyano, -COR¹⁰, -CO₂R¹⁰ or-S(O)_mRⁿ;

R¹⁰ represents hydrogen or straight- or branched-chain alkyl group containing up to six carbon atoms;

R¹¹ represents Cι_₆ alkyl, C_1-6 haloalkyl, C_1-6 cyanoalkyl, C_3-8 cycloalkyl optionally substituted with halogen, cyano or C_1-4 alkyl; or phenyl optionally substituted with one to three of the same or different halogen, nitro, cyano, Cι_-4 haloalkyl, C_1- alkyl, C.-4 alkoxy or-S(O)_mR¹²;

R¹² represents Cι_ alkyl; each Q independently represents C_1-4 alkyl or -CO2R wherein R is C_1- alkyl; is zero, one or two; n is zero or an integer from one to four; r is one, two or three; and p is zero or an integer from one to six.

12. A suspoemulsion formulation according to claim 11 , wherein the 2-(substituted benzoyl)-l,3-cyclohexanedione of formula (II) is selected from the group consisting of 2- (2 ' -nitro-4 ' -methylsulphonylbenzoyl)- 1 ,3-cyclohexanedione, 2-(2 ' -nitro-4 ' - methylsulphonyloxybenzoyl)-l,3-cyclohexanedione, 2-(2'-chloro-4'- methylsulphonylbenzoyl)- 1 ,3-cyclohexanedione, 4,4-dimethyl-2-(4-methanesulphonyl-2- nitrobenzoyl)-l,3-cyclohexanedione, 2-(2-chloro-3-ethoxy-4-methanesulphonylbenzoyl)- 5-methyl- 1 ,3 -cyclohexanedione and 2-(2-chloro-3 -ethoxy-4-ethanesulphonylbenzoyl)-5- methyl- 1 ,3 -cyclohexanedione.

13. A suspoemulsion formulation according to claim 12, wherein the 2-(substituted benzoyl)-l,3-cyclohexanedione is 2-(2'-nitro-4'-methylsulphonylbenzoyl)-l,3- cyclohexanedione.

14. A suspoemulsion formulation according to any one of claims 1 to 13, wherein the stabilizing metal salt is selected from the group consisting of calcium, beryllium, barium, titanium, magnesium, zinc, iron, cobalt, nickel and copper salts.

15. A suspoemulsion formulation according to claim 14, wherein the stabilizing metal salt is selected from the group consisting of magnesium, manganese, zinc, iron, cobalt, nickel and copper salts.

16. A suspoemulsion formulation according to claim 15, wherein the stabilizing metal salt is a copper salt.

17. A method for controlling the growth of undesirable vegetation, said method comprising applying a formulation as claimed in claim 1 to 16 to the locus of such vegetation.

18. Use of a suspoemulsion formulation as claimed in any one of claims 1 to 16 for the control of the growth of undesirable vegetation.