AU2019100546A4 - Agricultural chemical composition - Google Patents

Abstract

An emulsifiable concentrate comprising the herbicide pinoxaden and a solvent composition comprising at least two of the groups: 5 (i) acetophenone; (ii) propylene carbonate and butylene carbonate; and (iii) N-(Cl to C4 alkyl) pyrrolidone. <filename>

Description

Field [0001] The invention relates to an emulsifiable concentrate of the herbicide pinoxaden, to preparation of the composition and to a method for control of weeds using the composition.

Background [0002] Pinoxaden is the common name of the herbicide [8-(2,6-diethyl-4methylphenyl)-7-oxo-1,2,4,5-tetrahydropyrazolo[1,2-d][1,4,5]oxadiazepin-9-yl] 2,2dimethylpropanoate. It is a pro-herbicide (by hydrolysis of the pivalate ester to give the corresponding enol) and is used for control of grass weeds in cereal crops such as wheat, barley and rye crops.

[0003] Emulsifiable concentrates of pinoxaden are disclosed in AU2006331031 which addresses the stability of the compositions, particularly in relation to decomposition, hydrolysis or transesterification. The emulsifiable concentrate compositions are said to have improved stability by virtue of the use of certain alcohol solvents and in particular tetrahydrofurfuryl alcohol. The commercial product “Axial 100 EC” selective herbicide available from Syngenta (Axial is a trademark of Syngenta) contains 10 wt% pinoxaden and 20 wt% to 40 wt% tetrahydrofurfuryl alcohol. AU2006331031 examines the use of ketone solvent used to formulate an emulsifiable concentrate in EP1062217 and asserts that the emulsifiable concentrate formulations based on the ketone solvent do not have adequate stability.

AU2006331031 replaces the ketone with tetrahydrofurfuryl alcohol with an assertion, based on experimental evidence of Example 1, that tetrahydrofufuryl alcohol provides a significant improvement in stability.

[0004] The discussion of documents, acts, materials, devices, articles and the like is included 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.

2019100546 22 May 2019

Summary of Invention [0005] We have found that despite the previous reports of instability combinations of certain solvents selects from ketones, carbonates and N-(Ci to C₄ alkylpyrrolidones provide enhanced stability of pinoxaden without the need to use alcohol solvents such as tetrahydrofurfuryl alcohol.

[0006] Accordingly we provide an emulsifiable concentrate comprising the herbicide pinoxaden and a solvent composition comprising at least two of the groups:

(i) acetophenone;

(ii) propylene carbonate and butylene carbonate; and (iii) N-(Ci to C₄ alkyl) pyrrolidone.

[0007] In one embodiment the solvent combination comprises acetophenone and N-(Ci to C₄ alkyl) pyrrolidone (particularly N-methylpyrrolidone) and in a further embodiment the combination comprises acetophenone and at least one of propylene carbonate and butylene carbonate.

[0008] In a preferred set of embodiments we provide an emulsifiable concentrate comprising the herbicide pinoxaden and a solvent composition comprising:

(a) at least one solvent selected from acetophenone, propylene carbonate and butylene carbonate; and (b) at least one N-(Ci to C₄ alkyl) pyrrolidone.

[0009] The emulsifiable concentrate will typically include an emulsifier, In a particularly preferred embodiment the emulsifier is a non-ionic emulsifier and is preferably present in an amount of 20 g/L to 200 g/L, preferably 50 g/L to 150 g/L, of the emulsifiable concentrate composition [0010] The emulsifiable concentrate may comprise one or more non-ionic emulsifier selected from the group consisting of alkoxylated polypropylene glycol, alkyl polyoxyalkylene ether, ethylene oxide-propylene oxide block copolymer, alkoxylate alkyl phenol, natural oil ethoxylates (such as castor oil ethoxylates), ethoxylated tristyrylphenol and distyryl phenol formaldehyde condensate. A

2019100546 22 May 2019 particularly useful emulsifier comprises ethoxylated tristyrylphenol and ethoxylated nonylphenol.

[0011] There is further provided a method of control of weeds, such as weeds in cereal crops, comprising post-emergent application of the emulsifiable concentrate described herein, following dilution thereof with water to form an emulsion.

Detailed Description [0012] The term emulsifiable concentrate or EC as used herein relates to a concentrated water immiscible solution which, on dilution with water, forms an emulsion such as a spontaneous milky white emulsion comprising a dispersed water immiscible phase. Small amounts of water may be present in an EC (typically < 5% by weight) but the water is not present as a discrete phase. The ECs are typically transparent and will only be diluted with water or water- based composition such as aqueous fertilizers directly before application and form white to off-white dilutes.

[0013] Throughout the description and the claims of this specification the word comprise and variations of the word, such as comprising and comprises is not intended to exclude other additives, components, integers or steps.

[0014] The emulsifiable concentrate of pinoxaden includes a solvent composition comprising:

(a) at least one solvent selected from acetophenone, propylene carbonate and butylene carbonate; and (b) at least one N-(Ci to C4 alkyl) pyrrolidone.

[0015] The N-(Ci to C4 alkyl)pyrrolidones include N-methyl pyrrolidone, N-ethyl pyrrolidone, N-n-propyl pyrrolidone, N-isopropyl pyrrolidone , N-n-butyl pyrrolidone, Nsec-butyl pyrrolidone and N-tert-butyl pyrrolidone. N-methyl pyrrolidone is particularly preferred.

[0016] In particularly preferred embodiments the solvent composition comprises (a) acetophenone or propylene carbonate and (b) N-(C1 to C4 alkyl)pyrrolidone, particularly acetophenone and N-methyl pyrrolidone.

2019100546 22 May 2019 [0017] The solvent (a) is preferably present in an amount of from 30 g/L to 200 g/L, preferably from 50 g/L to 150 g/L. In a particularly preferred embodiment the solvent (a) is acetophenone present in an amount of from 30 g/L to 200 g/L, preferably from 50 g/L to 150 g/L such as 80 g/L to 120 g/L.

[0018] The solvent (b), for example N-methylpyrrolidone, is preferably present in an amount of from 30 g/L to 200 g/L, more preferably from 50 g/L to 150 g/L. In a particularly preferred embodiment the solvent (b) is N-methylpyrrolidone, present in an amount of from 30 g/L to 200 g/L, preferably from 50 g/L to 150 g/L such as 80 g/L to 120 g/L.

[0019] The components (a) and (b), particularly when (b) is N-methylpyrrolidone, will typically constitute 50 g/L to 400 g/L, preferably 100 g/L to 300 g/L of the emulsifiable concentrate. The ratio of components (a) to (b) in some embodiments are1:5 to 5:1 such as from 1:2 to 2:1 or 1.5:1 to 1:1.5. These ratios have been found to provide particularly good stability.

[0020] The emulsifiable concentrate may contain acetophenone and N-methyl pyrrolidone in a total amount of from 50 g/L to 400 g/L, preferably 100 g/L to 300 g/L such as 50 g/L to 400 g/L or 100 g/L to 300 g/L.

[0021] The emulsifiable concentrate may contain pinoxaden in solution in an amount of from 50 g/L to 300 g/L of emulsifiable concentrate, preferably 80 g/L to 200 g/L, more preferably 80 g/L to 150 g/L,. The weight ratio of acetophenone to Nmethylpyrrolidone in preferred embodiments is from 1:5 to 5:1 such as from 1:2 to 2:1 or 1:1.5 to 1.5:1.

[0022] The carrier solvent may, and preferably will, further comprise an aromatic hydrocarbon. Preferred water-insoluble aromatic solvents are aromatic hydrocarbons such as toluene, xylenes and naphthalene derivatives, in particular 1methylnaphthalene,and, mixtures of Ce-C-ie-aromatics such as, for example, the SOLVESSO series (Exxon Mobil). Typically the aromatic hydrocarbon is present in an amount of from 100 g/L to 700 g/L, preferably 300 g/L to 700 g/L of emulsifiable concentrate. Preferred co-solvent are Οθίθ aromatics available under the SOLVESSO trademark including a mixture of Cs to C12 di- and tri-alkyl benzenes, commercially available from Exxon Mobil as SOLVESSO 150™ and SOLVESSO 200™ . The more

2019100546 22 May 2019 preferred hydrocarbon solvents are naphthalene depleted such as SOLVESSO 150 ND and SOLVESSO 200N.D.

[0023] The emulsifiable concentrate composition preferably comprises a herbicide safenerfor pinoxaden. Cloquintocet-mexyl is the preferred safener and is typically present in an amount of from 5 g/L to 50 g/L such as 10 g/L to 40 g/L.

[0024] The emulsifiable concentrate composition will typically include an emulsifier preferably comprising a non-ionic emulsifier in an amount of 20 g/L to 200 g/L, preferably 50 g/L to 150 g/L of the emulsifiable concentrate.

[0025] The non-ionic emulsifier composition may comprise one or more selected from the group consisting of alkoxylated polypropylene glycol, alkyl polyoxyalkylene ether, ethyleneoxide-propylene oxide block copolymer, alkoxylate alkyl phenol such as an alkoxylated nonylphenol, natural oil ethoxylates (such as castor oil ethoxylates), ethoxylated tristyrylphenol and distyryl phenol formaldehyde condensate.

[0026] The emulsifiable concentrate may contain an emulsifier which comprises (a) ethoxylated tristyrylphenol and (b) at least one of alkoxylated nonylphenol and alkyl polyoxyalkylene ether. In a preferred embodiment the emulsifier comprises a mixture of (a) ethoxylated tristyrylphenol and (b) alkoxylated nonylphenol and/or alkyl polyoxyalkylene ether in a weight ratio [(a):(b)] of from 10:1 to 1:1 and preferably 10:1 to 2:1 such as 8:1 to 3:1.

[0027] In a more specific embodiment the emulsifiable concentrate comprises:

g/L to 150 g/L pinoxaden;

g/L to 50 g/L cloquintocet-mexyl;

/L to 150 g/L non-ionic emulsifier;

g/L to 150 g/L N-methylpyrrolidone;

g/L to 150 g/L acetophenone; and

300 g/L to 700 g/L aromatic hydrocarbon solvent

2019100546 22 May 2019 [0028] In a further specific embodiment the composition comprises g/L to 150 g/L pinoxaden;

g/L to 50 g/L cloquintocet-mexyl;

50g/L to 150 g/L non-ionic emulsifier;

50g/L to 150 g/L N-methylpyrrolidone;

50g/L to 150 g/L propylene carbonate; and

300g/L to 700 g/L aromatic hydrocarbon solvent.

[0029] In a further specific embodiment the composition comprises:

g/L to 150 g/L pinoxaden;

g/L to 50 g/L cloquintocet-mexyl;

50g/L to 150 g/L non-ionic emulsifier;

50g/L to 150 g/L acetophenone;

50g/L to 150 g/L propylene carbonate; and

300g/L to 700 g/L aromatic hydrocarbon solvent.

[0030] The presence of acetophenone and N-(C1 to C4 alkly)pyrrolidone (particularly n-methyl or N-butyl pyrrolidone NMP or NBP) is preferred as it was found to allow formulation with significantly less co-solvent which can transition into the aqueous phase upon dilution and thereby expose the formulation to the risk of active ingredient crystallisation. Such crystallisation often results in clogging of spray orifices or under-dosing of active as a result of the loss of crystalline precipitates.

[0031] The emulsifiable concentrate may comprise an anionic emulsifier but generally this is not a requirement for a stable emulsion. Indeed, in many embodiments the emulsifiable concentrate contains no more than 5 g/L anionic emulsifier, such as no more than 2 g/L, and may be free of anionic emulsifier.

2019100546 22 May 2019 [0032] The composition may comprise one or more further actives selected from the group consisting of herbicides, fungicides, insecticides, plant growth regulators, biologicals and mixtures of two or more thereof.

[0033] The emulsifiable concentrate may comprise a further herbicide such as selected from the group consisting of sulfonyl ureas, synthetic auxins such as picolinates and aryl picolinates, triazolopyrrimidines, cyclohexanedione oximes, thiocarbamates, hydroxybenzonitriles and dinitroanilines.

[0034] In a further embodiment the invention provides a method of applying a the emulsifiable concentrate composition comprising:

providing an emulsifiable concentrate of as herein disclosed;

combining the emulsifiable concentrate with a water and optionally a liquid nitrogenous fertilizer to form an oil-in-water emulsion having a discontinuous oil phase comprising the water immiscible solvent; and applying the oil in water emulsion to weeds to be controlled preferably by spray application.

[0035] The emulsifiable concentrate may be combined with the liquid fertilizer with additional water being combined with the concentrate and/ or the fertilizer or alternatively in some cases an emulsion may be formed with the neat concentrate using liquid nitrogenous fertilizer in the form supplied by the manufacturer.

[0036] The invention also provides a method of control of weeds in cereal crops such as wheat and barley, comprising post-emergent application of the emulsifiable concentrate according to any one of the previous claims following dilution thereof. The diluted composition may be applied by spraying over the crop containg weeds.

[0037] The diluted composition may, for example be applied at a rate of 50 g to 400 g active per hectare to provide weed control in crops. The composition is particularly useful in the control of wild oats in crops such as barley and wheat.

[0038] The invention will now be described with reference to the following Examples. It is to 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.

2019100546 22 May 2019

Examples [0039] Comparative Example 1 [0040] An EC composition was prepared as set out in Table 1 using a water immiscible solvent benzyl acetate (Jeffsol AG 1705). Whilst benzyl acetate provided the required solvency and was toxicologically & environmentally favourable, the composition was seen to exhibit significant degradation of Pinoxaden as shown in the results presented in Table 1 part (a).

[0041] Table 1

COMPONENT	g/L
Pinoxaden 96.6%	100 (103.5)
Cloquintocet-mexyl 100%	25 (25.6)
NANSA EVM 70/2E	50
TERMUL 200	50
JEFFSOL AG 1705	Balance (828.9)

[0042] Table 1a

Pre-accelerated storage condition	Post-accelerated storage condition
Determination GCFID	g/L	Determination GC-FID	g/L
Pinoxaden	90.6	Pinoxaden	71.0
Cloquintocet-mexyl	23.7	Cloquintocet-mexyl	24.2

Preparative method:

[0043] In a 100ml beaker, 5.4g of Pinoxaden and 2.6g of Cloquintocet-mexyl was added, followed by 5.0g of NANSAR EVM 70/2E, 5g of TERMUL 200 and the solvent.

The solution was stirred whilst heating to approximately 60°C until the [0044] Pinoxaden and Cloquintocet-methyl was completely dissolved and the solution was homogenous.

[0045] Benzyl acetate was found to result in poor stability and could not be stabilised by the addition of VTMO = Trimethoxyvinylsilane CAS-No. 2768-02-7.

[0046] Comparative Examples 2 A-G [0047] Compositions of CE 2 A-G were prepared by combining the components shown in Table 2 in accordance with the procedure described above.

2019100546 22 May 2019 [0048] Table 2

COMPOSITIONS	A	B	c	D	E	F	G
	g/L	g/L	g/L	g/L	g/L	g/L	g/L
Pinoxaden 100%	100	100	100	100	100	100	100
Cloquintocet-mexyl 100%	25	25	25	25	25	25	25
TERSPERSE 2202	100	100	100	-	-	-	50
TERSPERSE 2218	-	-	-	100	100	100
TERMUL200	-	6.44	-	-		-	50
VTMO	8.24	-	8.24	8.24	8.24	-	8.24
JEFFSOL AG 1705	Bal.	Bal.	200	Bal.	200	200	200
SOLVESSO 200	-	-	Bal.	-	Bal.	Bal.	Bal.

[0049] Accelerated storage showed significant degradation recorded in Table 2 part (a).

[0050] Table 2 (a)

Post accelerated storage condition	A	B	C	D	E	F	G
Determination GC-FID	g/L	g/L	g/L	g/L	g/L	g/L	g/L
Pinoxaden	N.T.	57.4	44.7	56.2	N.T.	N.T.	N.T.
Cloquintocet-mexyl	N.T.	23.0	22.2	24.2	N.T.	N.T.	N.T.

SOPROPHOR® BSU non-ionic surfactant is a tristyrylphenol ethoxylate available from Solvay Chemicals Pty Ltd

TERMUL®200 non-ionic surfactant is a propylene oxide ethylene oxide copolymer mono-nonylphenyl ether of Huntsman Corporation Australia Pty Ltd

N-methylpyrrolidone is also referred to as 1-methyl 2-pyrrolidone and as available from Recochem Inc

SOLVESSO 200 N.D. solvent is a C₁₀-i3 hydrocarbon aromatics solvent <1% naphthalenes of Exxon Mobil

NANSAR EVM® anionic surfactant containing approx. 60% calcium dodecyl benzene sulfonate

2019100546 22 May 2019

VTMO is Trimethoxyvinylsilane

TERSPERSE 2202 anionic surfactant is salt of phosphate esters of ethoxylated tristyrylphenol by Huntsman Corporation Australia Pty Ltd

TERSPERSE 2218 anionic surfactant is salts of sulphated ethers of ethoxylated Tristyrylphenol by Huntsman Corporation Australia Pty Ltd

Comparative Examples 3 A-D [0051] Various solvent & emulsifier candidates were considered and chosen according to theory to avoid trans esterification reactions as observed with benzyl acetate. Upon examination, no degradation of the Pinoxaden active ingredient was observed in any the carefully considered excipient compositions.

[0052] SOLVESSO 200 N.D is a naphthalene depleted (1 %) grade of aromatic 200 and it was discovered that the N.D grade SOLVESSO 200 from Exxon Mobil provided more solvency for Pinoxaden & Cloquintocet-mexyl than standard grade aromatic 200. The compositions are shown in Table 3 and the accelerated storage in Table 3 (a).

[0053] Table 3

	Q-A	Q-A1	Q-B	Q-B1	Q-C	Q- C1	Q-D	Q- D1
COMPOSITIONS	g/L	g/L	g/L	g/L	g/L	g/L	g/L	g/L
Pinoxaden 100%	100	100	100	100	100	100	100	100
Cloquintocet-mexyl 100%	25	25	25	25	25	25	25	25
TERMUL3150	-	50	-	50	-	50	-	50
TERMUL200	-	50	-	50	-	50	-	50
SOLVESSO 200 N.D.	-	-	858	758	763	663	496	417
Acetophenone	904	904	-	-	-	-	-	-
N-Methyl Pyrrolidone	-	-	-	-	100	100	-	-
l-Octanol	-	-	-	-	-	-	300	300

2019100546 22 May 2019 [0054] Table 3(a)

Post accelerated storage	Q-A	Q-A1	Q-B	Q-B1	Q-C	Q- C1	Q-D	Q- D1
Determination GC-FID	g/L	g/L	g/L	g/L	g/L	g/L	g/L	g/L
Pinoxaden	104	102	106	106	102	103	105	103

Preparation Method [0055] Pinoxaden 100 EC as formulated in the comparative examples was prepared as described below:

[0056] In a suitable vessel 105 g/L of Pinoxaden 100% and 25 g/L of Cloquintocet-mexyl was added followed by 85 g/L Termul 3150 and 15 g/L Termul 200. The solvents being 583.84 g/L Solvesso 200 ND, 100 g/L Acetophenone and 100 g/L N-methyl Pyrrolidone were then added. The solution was stirred whilst heating to approximately 60 °C until the Pinoxaden and Cloquintocet-mexyl was completely dissolved and the solution was homogeneous.

[0057] Example 1 [0058] Stability was found to be significantly improved by using a combination of two solvents acetophenone and N-methyl pyrrolidone. The use of SOLVESSO 200 N.D was found to further optimise cold temperature stability. The emulsification of the system was achieved and optimised without the more typically used anionic emulsifier CaDDBS (calcium dodecylbenzene sulfonate) containing alcohol in favour of a 100 g/L dual non-ionic emulsifier system in a specific ratio of 85:15.

[0059] CAS # 99734-09-5 Tristyrlphenol ethoxylate (SOPROPHOR BSU from Solvay or TERMUL 3150 from Huntsman) [0060] CAS # 37251-69-7 Oxirane, methyl-,polymer with oxirane, mono (nonylphenyl) ether (TERMUL 200 from Huntsman) [0061] The optimised final composition is shown in Table 4 below. The composition was scaled to 5000 mL Batch Size and a study conducted according to the APVMA Guidelines.

2019100546 22 May 2019 [0062] The study examined the effect of accelerated storage on the stability of the product in proposed commercial packaging material and concluded the product was stable to heat for 2 weeks at 54 °C and therefore expected to be shelf stable for at least two years.

[0063] The study examined the effect of a cold storage condition for 7 days at 0 °C. The absence of any separation or crystal growth (seeded condition) concluded the product to be cold storage stable.

[0064] Table 4

Component	g/L
Pinoxaden 100%	105
Cloquintocet-mexyl 100%	25
TERMUL 3150 or SOPROPHOR BSU	85
TERMUL 200	15
Acetophenone	100
N-Methyl Pyrrolidone	100
SOLVESSO 200 N.D.	Bal. (583.84)

[0065] Pinoxaden 100 EC is formulated in the invention example in a batch process. A description of the method of manufacture and the sequence of operations followed for Example 1 is described below:

1. TERMUL 200 requires heating to become fluid. Heat this component in a water bath at 60 °C and maintain it in a completely fluid state prior to addition.

2. Acetophenone and SOPROPHOR BSU are semi solid at temperatures below 25 °C and may similarly require heating in a water bath to improve fluidity dependent upon the ambient temperature conditions.

3. Charge the SOLVESSO 200 ND into a suitable vessel equipped with a propeller type stirrer.

4. Commence mixing and add N-methylpyrrolidone.

5. Maintain mixing and add the SOPROPHOR BSU.

6. Maintain mixing and add the TERMUL 200.

7. Maintain mixing and add the Acetophenone.

2019100546 22 May 2019

8. Maintain mixing and add the Cloqiuntocet-mexyl Technical followed by the Pinoxaden Technical.

9. Continue mixing until complete dissolution of the active ingredients is obtained.

10. Turn off stirrer and examine the product according to the specification. Adjust if required.

[0066] The density was in the range 1.0007 to 1.017 g/ml.

[0067] N-Methyl Pyrrolidone may be replaced by N-butyl pyrrolidone which has a safer toxicity profile than N-Methylpyrrolidone.

[0068] TERMUL 5459 alkoxylated alcohol surfactant is nonylphenol ethoxylate free and may be used in place of TERMUL 200. Although this is different emulsifier chemistry to that of TERMUL 200, TERMUL 5459 is known to substitute in most instances. The proportion and ratio may be modified to optimise stability and emulsion performance with different surfactants.

[0069] Alkyl pyrrolidones of longer alkyl chain length than N-Methyl Pyrrolidone are demonstrated to have significantly improved toxicological profiles such that they are currently unrestricted by regulatory authorities in the EU. Generally, the solvency power of these solvents decreases with increasing alkyl chain length, so they are not direct substitutes for NMP. GENAGEN NBP by Clariant is commercially available Nbutyl pyrrolidone and is already being accepted as an NMP replacement in EU formulations. The proportion may be increased..

[0070] The proportion of Acetophenone 100 g/L and an alkly pyrrolidone (NMP or NBP) in limited proportion (100 g/L NMP or <100 g/L NBP) provides for significantly less co-solvent which can transition into the aqueous phase upon dilution and thereby expose the formulation to active ingredient crystallisation risk.

[0071] Properties of the relevant solvents are shown in Table 5.

2019100546 22 May 2019 [0072] Table 5

Polar Co-Solvent	Required Proportion	Water Solubility 25 °C	Flash Pt (C.Cup)	Log Kow
THFA	Disclosed 300 g/L	Miscible	74 °C	-0.367
Acetophenone	Evaluated 100 g/L (+NMP or NBP)	Slightly Soluble 6.1 g/L	76 °C	1.58
N-MP	Evaluated 100 g/L (+Acetophenone)	Miscible	86 °C	-0.38
N-BP	Proposed < 100 g/L (+Acetophenone)	Miscible	108 °C	1.27
Propylene Carbonate	Not determined	Very soluble 175 g/L	135 °C	-0.41
Butylene Carbonate	Not determined	Sparingly soluble 33.8 g/L	128 °C	0.01
Cyclohexanone	Disclosed 100 - 200 g/L	Sparingly soluble 25 g/L	44 °C	0.81

[0073] With reference to the table above Table the relative proportion and solubility in water of polar co-solvent candidate is a primary consideration for the prevention of problematic crystallisation of active ingredient upon dilution.

[0074] In cases where co-solvent water solubility and proportion are closely similar the co-solvent candidate with the largest +ve Log Kow (most lipophilic) minimise this phenomenon.

[0075] THFA as used in the Axial 100 EC product at 30% is completely miscible with water and undesirable regarding risk of problematic crystallisation upon dilution.

[0076] Propylene and butylene carbonates may be used to provide the required solvency and stability for the Pinoxaden + safener active ingredients. Acetophenone 100 g/L + NMP (and/or NBP) 100 g/L provide a more favourable dilution crystallisation risk profile.

[0077] Example 2 - Comparison of compositions containing N-Butyl Pyrrolidone and N-Methyl Pyrrolidone.

[0078] Compositions for comparative assessment were prepared according to the

Table. Cold stability was then conducted as per CIPAC MT 39.3 (7 days @ 0 °C, seeded cold storage condition). Cold stability performance was determined at the conclusion of the cold storage period and reported as quantity of observed crystallisation.

[0079] Table 6

2019100546 22 May 2019

	Example 2a	Example 2b
Composition	g/L	mL/L	g/L	mL/L
Pinoxaden 100 %	105		105
Cloquintocet-mexyl 100 %	25	25
Emulsifiers	100	100
Tetra hydrofurfury I Alcohol (1.051 g/mL)
N-butyl pyrrolidone (0.961 g/mL)			93.0	96.8
N-methyl pyrrolidone (1.033 g/mL)	100	96.8
Acetophenone (1.032 g/mL)	100	96.9	100	96.9
Solvesso 200 N.D (0.984 g/mL)	584	593	584	593
Total Solvent	787 mL	787 mL
Cold Crystallisation (mL/100 mL)	< 0.05	6

[0080] Example 3 - Compositions containing Propylene Carbonate and N-Methyl Pyrrolidone replacement.

[0081] Compositions for comparative assessment were prepared according to the Table 7.

[0082] Cold stability was then conducted as per CIPAC MT 39.3 (7 days @ 0 °C, seeded cold storage condition). Cold stability performance was determined at the conclusion of the cold storage period and reported as quantity of observed crystallisation.

[0083] Table 7

	Comparative	Ex 3a	Ex3b
Composition	g/L	g/L	g/L
Pinoxaden 100 %	105	105	105
Cloquintocet-mexyl 100 %	25	25	25
TERMUL 3150	85	85	85

2019100546 22 May 2019

TERMUL 5459	15	15	15
N-butyl pyrrolidone (0.961 g/mL)	275	110	55
Acetophenone (1.032 g/mL)	0	166	221
Solvesso 200 N.D	To volume
Cold Crystallisation (mL/100 mL)	7	3	3

[0084] Compositions of N-Butylpyrrolidone and acetophenone were found to be inferior to N-methylpyrrolidone and acetophenone.

[0085] Example 4 - Composition containing propylene carbonate and Nmethylpyrrolidone [0086] Compositions for comparative assessment were prepared according to the Table 8.

[0087] Cold stability was then conducted as per CIPAC MT 39.3 (7 days @ 0 °C, seeded cold storage condition). Cold stability performance was determined at the conclusion of the cold storage period and reported as quantity of observed crystallisation.

[0088] Table 8

	Ex 4a	Ex 4b	Ex 4c	Ex 4d	Ex 4e
Composition	g/L	g/L	g/L	g/L	g/L
Pinoxaden 100 %	105	105	105	105	105
Cloquintocet-mexyl 100 %	25	25	25	25	25
TERMUL 3150	85	85	85	85	85
TERMUL 5459	15	15	15	15	15
Propylene Carbonate (1.20 g/mL)	190	143	120	95	48
Acetophenone (1.032 g/mL)	55	110	100	166	221
Solvesso 200 N.D
Cold Crystallisation (mL/100 mL)	1	1	0	3	3

[0089] Excellent cold stability was achieved by Example 4C.

2019100546 22 May 2019 [0090] Propylene Carbonate solvency as shown by example 4c was found to be similar to that of N-methylpyrrolidone.

[0091] Example 5 - Comparative Pinoxaden degradation of compositions with suitable cold stability.

[0092] Sample compositions showing acceptable cold stability (solvency) were prepared according to Table 9 and assigned to accelerated storage stability. AU registered.

[0093] Accelerated storage stability was then conducted by placing the samples at an elevated temperature condition (54 ± 2 °C) for 14 days. At the end of the elevated temperature period the active ingredient contents of the samples were analysed using a Gas Chromatographic method (QCM.116.02). Pinoxaden degradation was then evaluated allowing comparison of the compositions. A preferred limit for Pinoxaden degradation is, < 10% degradation post accelerated storage condition. Typically, the preferred composition containing acetophenone and N-methylpyrrolidon displays 6-8 % [0094] Table 9

	Propylene carbonate g/L	acetophenone + NMP g/L
Example	comparison	comparison	Ex 9a	Ex 9b
Pinoxaden 100 %	105	105	105	105
Cloquintocet-mexyl 100 %	25	25	25	25
TERMUL3150	85	85	85	85
TERMUL200		15	15
TERMUL 5459	15			15
N-methyl pyrrolidone (1.033 g/mL)			100	100
Propylene Carbonate (1.20 g/mL)	342	342
Acetophenone (1.032 g/mL)			100	100
Solvesso 200 N.D (0.984 g/mL)	494	494	584	584
Pinoxaden degradation	8-10 %	6 - 8 %
Cloquintocet-mexyl degredation	Nil	Nil

[0095] Propylene Carbonate in combination with Acetophenone displayed higher Pinoxaden degradation than Propylene Carbonate as a solo polar solvent system.

2019100546 22 May 2019 [0096] Example 6 - Bioefficacy [0097] The efficacy and crop safety of the composition of Example 1 for the control of wild oats in barley when compared to a reference formulation of “Axial” 100EC of Syngenta Australia Pty Ltd of the following approximate composition shown in Table 6:

[0098] Table 10

	Axial ™100 EC
COMPONENT	g/L
Pinoxaden	100
Cloquintocet-mexyl	25
Tetrahyrofurfural alcohol	300-600
Solvent naphtha (petroleum), highly aromatic	300-600
Other ingredients including surfactant	Balance

[0099] Method [0100] Treatments were applied post-emergence as a coarse spray using a handheld compressed gas sprayer equipped with 4 HMD green nozzles in a carrier volume of 100 L/ha and a delivery pressure of 220 kPa in barley.

[0101] Barley cv. Shepherd had been previously planted on May 20 at a rate of 39 kg/ha in a row spacing of 36 cm rows with a modified Morris Chisel Seeder. Soil type was a Grey Brigalow Clay with a medium clay texture. Good soil moisture was present at the time of treatment.

[0102] Wild oats were present at an average density of 145 plants per square metre determined by counting 10 x 0.25 m2 quadrats across the trial area.

[0103] Treatments were arranged in a Randomized Complete Block Design with 4 replicates with each plot being 2 x 10 m.

[0104] Crop phytotoxicity was assessed 14 days after application (DAA) using a subjective assessment of injury on a 0-100 scale. Subjective assessments of weed control were undertaken 14, 28 and 74 days after application using a subjective 0-100

2019100546 22 May 2019 scale where 0=no effect and 100=complete weed control. Wild oats emerging subsequent to treatment were not included in determining wild oat control. Counts of wild panicles per square metre were determined counting 5x1 square metre quadrats per plot 74 DAA. Late germinating wild oats present were not present at the reproductive stage at the time of this assessment.

[0105] Data was analysed using ARM 9 data management system using a simple analysis of variance. Treatment means were separated using Duncan’s New Multiple Range Test at the 5% level of probability. Treatment means sharing common letters are statistically similar according to this test.

[0106] Broadleaf weeds were controlled using a separate application of 25 g/ha Paradigm plus 0.5% Uptake on June 25, 2015.

[0107] Conditions were moist at the time of treatment following good rainfalls in May. Further good rain occurred in June following application (25 mm) and also July. June rainfalls stimulated a further significant germination of wild oats that was disregarded for the purposes of evaluating the control of test treatments. Several frosts occurred during July and into August until just prior to the final assessment.

[0108] Commercially acceptable wild oat control was achieved in all treatments 28 DAA reflecting the favourable growing conditions and relatively younger growth stages of wild oats targeted. Slightly lower control was noted in plots treated with 150 mL/ha. No significant differences in performance were noted between formulations.

[0109] Crop Safety [0110] No phytotoxicity symptoms were noted in any treatment 14 DAA and this absence of symptoms was maintained throughout the life of the experiment.

[0111] Conclusions [0112] 1. The composition of Example 1 demonstrated bioequivalence to Axial

100 EC in respect of crop safety.

[0113] 2. The compositions of Example 1 demonstrated bioequivalence to Axial

100 EC in respect of control of wild oats.

Claims (21)

1. Claims

   1. An emulsifiable concentrate comprising the herbicide pinoxaden and a solvent composition comprising solvents selected from at least two of the groups:

   (i) acetophenone;

   (ii) propylene carbonate and butylene carbonate; and (iii) N-(Ci to C₄ alkyl) pyrrolidone.
2. 2. An emulsifiable concentrate comprising the herbicide pinoxaden and a solvent composition comprising:

   (a) at least one solvent selected from acetophenone, propylene carbonate and butylene carbonate; and (b) at least one N-(Ci to C₄ alkyl)pyrrolidone.
3. 3. The emulsifiable concentrate of claim 2, wherein the solvent composition comprises acetophenone and N-methylpyrrolidone.
4. 4.. The emulsifiable concentrate of any one of the previous claims, wherein the pinoxaden is present in an amount of from 50 to 300 g/L of emulsifiable concentrate, preferably 80 g/L to 300 g/L, more preferably 80 g/L to 150 g/L.
5. 5. The emulsifiable concentrate of any one of the previous claims wherein the composition comprises a herbicide safener.
6. 6. The emulsifiable concentrate of any one of claims 2 to 5 comprising the herbicide saftener cloquintoxet-mexyl.
7. 7. The emulsifiable concentrate of any one of the previous claims wherein acetophenone and N-methylpyrrolidone are present in a total amount of from 50 g/L to 400 g/L, preferably 100 g/L to 300 g/L.

   2019100546 22 May 2019
8. 8. The emulsifiable concentrate of any one of the previous claims wherein the weight ratio of acetophenone to N-methylpyrrolidone is from 1:5 to 5:1, preferably from 1:2 to 2:1.
9. 9. The emulsifiable concentrate of any one of the previous claims, wherein the carrier solvent further comprises aromatic hydrocarbon.
10. 10. The emulsifiable concentrate of claim 9, wherein the aromatic hydrocarbon is present in an amount of from 100 to 700 g/L, preferably 300 to 700 g/L.
11. 11. The emulsifiable concentrate of any one of the previous claims comprising a non-ionic emulsifier in an amount of 20 g/L to 200 g/L, preferably 50 g/L to 150 g/L.
12. 12. The emulsifiable concentrate of any one of the previous claims comprising a non-ionic emulsifier composition comprising one or more selected from the group consisting of alkoxylated polypropylene glycol, alkyl polyoxyalkylene ether, ethyleneoxide-propylene oxide block copolymer, alkoxylated alkyl phenol, natural oil ethoxylates (such as castor oil ethoxylates), ethoxylated tristyrylphenol and distyryl phenol formaldehyde condensate.
13. 13. The emulsifiable concentrate of any one of the previous claims having an emulsifier comprising (a) ethoxylated tristyrylphenol and (b) at least one of alkoxylated nonylphenols and alcoholalkoxylates.
14. 14. The emulsifiable concentrate of claim 13 wherein the ratio of emulsifiers of type (a) to type (b) is from 10:1 to 2:1..
15. 15. The emulsifiable concentrate of any one of the previous claims comprising:

    50 g/L to 150 g/L pinoxaden;

    5 g/L to 50 g/L cloquintocet-mexyl;

    20 g/L to 150 g/L non-ionic emulsifier;

    50 g/L to 150 g/L N-methylpyrrolidone;

    50 g/L to 150 g/L acetophenone; and

    2019100546 22 May 2019

    300 g/L to 700 g/L aromatic hydrocarbon solvent.
16. 16. The the emulsifiable concentrate composition of claim 1 comprising:

    50 ZL to 150 g/L pinoxaden;

    5 g/L to 50 g/L cloquintocet-mexyl;

    50g/L to 150 g/L non-ionic emulsifier;

    50g/L to 150 g/L acetophenone;

    50g/L to 150 g/L propylene carbonate; and

    300g/L to 700 g/L aromatic hydrocarbon solvent.
17. 17. The emulsifiable concentrate of any one of the previous claims containing no more than 5 g/L anionic emulsifier.
18. 18. The emulsifiable concentrate of any one of the previous claims further comprising a herbicide selected from sulfonyl ureas, synthetic auxins, triazolopyrrimidines, cyclohexanedione oximes, thiocarbamates, hydroxybenzonitriles and dinitroanilines.
19. 19. A method of control of weeds in cereal crops comprising post-emergent application of the emulsifiable concentrate according to any one of the previous claims following dilution thereof.
20. 20. The method of control of weeds in cereal crops of claim 18, wherein the cereal crops are wheat or barley.
21. 21. The method of control of weed of claim 18 or claim 19 wherein the diluted composition is applied at a rate of 50 g/ha to 400 g/ha.