AU620551B2

AU620551B2 - A plant treatment composition

Info

Publication number: AU620551B2
Application number: AU19489/88A
Authority: AU
Inventors: David Charles Gill
Original assignee: Nomix Chipman Ltd
Current assignee: Nomix Chipman Ltd
Priority date: 1987-06-17
Filing date: 1988-06-17
Publication date: 1992-02-20
Anticipated expiration: 2008-06-17
Also published as: AU1948988A

Description

A PLANT TREATMENT COMPOSITION BACKGROUND OF THE INVENTION

This invention relates to a plant treatment composition, more particularly a pestiσidal composition in which the pesticide is a herbicide, insecticide, fungicide, seed germination stimulant, plant growth regulator, a mixture of these and the like. Particularly preferred are compositions based on the known herbicide N-phosphonomethylglycine (N-PMG) and/or agriculturally acceptable salts thereof and mixtures of N-PMG and such agriculturally acceptable salts thereof. This invention also relates to a process for preparing an agriculturally useful composition. The herbicide N- PMG is also commonly known by the name glyphosate. ϋ-S Patent Specification No. 4609148 (David Gill) discloses spray equipment which is said to be useful for the application of oil based herbicides. The document discloses that it is becoming increasingly common for herbicides to be applied in the form of water based emulsions. These are highly efficient and very small quantities, if properly applied, can be used to treat large areas. However, to be effective, the herbicides must be applied in the form of fine droplets of uniform size and distribution. The nature of the herbicide, which is commonly a viscous liquid having a viscosity, for example, of 20 to 40 centistokes, has made it difficult for this requirement to be met.

European Patent Specification No. 0 220 902 discloses liquid, phytoactive compositions and methods of use characterised in that the composition comprises (a) an N-phosphonomethyl-N-carboxymethyl compound, (b) one or more liquid nonionic surfactant, (c) a dispersing medium for the said N-phosphonomethyl N- carboxymethyl compound and (d) one or more inert adjuvants.

European Patent Specification No. 0 039 144, discloses pesticidal formulations said to be suitable for electrodynamic spraying and solutions suitable for use in making them. The pesticidal liquid formulations are said to comprise a non-polar liquid diluent and 0.5 to 80% by weight of pesticide, the formulation having a viscosity of 1 to 50 centistokes.

B.N. MacDiarmind, New Products, Proc. 27th N.Z. Weed and Pest Control Conf., "A New Polyvinyl Polymer Spray Additive For Drift Control" discloses that a polyvinyl polymer was found to increase the stability and size of spray droplets without appreciably altering the viscosity of the spray solution.

N-phosphonomethylglycine (glyphosate) is well known as a foliage acting herbicide, in particular in agriculturally acceptable salt form. In the free acid form, glyphosate has low water solubility, and because of this typical commercial formulations contain a water soluble salt of glyphosate. For example, in Roundup (Registered Trade Mark) herbicide, glyphosate is formulated as the isopropylamine salt.

The commercial formulation of Roundup Herbicide is labelled in many countries for this application through a variety of equipment including boom equipment, controlled droplet application, (wherein the formulation is subjected to a spinning disc), hand-held and high volume equipment and selective equipment, In particular the use of Roundup herbicide is registered for use in gravity fed straying systems including those of the Nomix design, more particularly disclosed in UK published Patent Application No. 2131327 and UK published Patent Application No. 2136318 which disclose spraying equipment. The spraying equipment comprises a tubular support member, having a spraying head at one end and a handle at the other. A supply duct and an electrical lead extend through the interior of the support member to supply fluid and electrical power to a rotary atomising disc and a motor in a housing for the driving disc. The supply duct communicates through the handle with a container for the fluid, and the lead is connected to a battery. It is an object of the invention to provide an improved method for the application of plant treatment agents to the desired locus, e.g. a plant.

It is another object of the invention to provide an improved composition for the application of plant treatment agents to the desired locus of application. It is yet another object of the invention to provide an improved system for the delivery of plant treatment agents to the desired locus of application. It is still another object of the invention to provide a ready-to-use system and method for the delivery of plant treatment agent to the desired locus whereby the efficacy of plant treatment agent is improved.

SUMMARY! OF THE INVENTION According to one aspect of the present invention there is provided a method of distributing a plant treatment agent comprising:

(i) providing an aqueous composition comprising (a) a plant treatment agent and/or mixtures thereof and (b) a polymer in an amount sufficient to increase the flowability of the aqueous composition to a flowability at 25°C such that the time elapsed for 100ml of the composition to pass through a measurement orifice of a Ford B2 cup is in the range of from about 60 to about 100 seconds; and

(ii) passing said aqueous composition under low pressure through a restriction at a low flow rate to a distribution element from which the aqueous composition is released. The restriction is typically an orifice.

According to a second aspect of the present invention there is provided a composition comprising

(a) a plant treatment agent and/or mixtures thereof and

(b) a polymer in an amount sufficient to increase the flowability of the aqueous composition to a flowability at 25°C such that the time taken for 100ml of the composition to pass through a measurement orifice of a Ford B2 cup is in the range of from about 60 to about 100 seconds.

According to a third aspect of the present invention, there is provided a dispensing package for an aqueous composition, said package comprising a collapsible container which is filled with said composition and which has an opening means through which the composition may be dispensed, said composition comprising (a) a plant treatment agent and/or mixtures thereof and (b) a polymer in an amount sufficient to increase the flowability of the aqueous composition to a flowability at 25°C such that the time taken for 100ml of the composition to pass through a measurement orifice of a Ford B2 cup is in the range of from about 60 to about 100 seconds. Preferably, the container is a collapsible bag. Such contains are described in British Published Patent Application No. 2136321, which is incorporated herein by reference in its entirety.

DETAILED DESCRIPTION

The Ford B2 cup test is an ASTM standard test (designated 1200/82) for determining the viscosity, more correctly the flowability, of liquids. The test involves maasuring the time taken for 100 ml of a liquid to pass through an orifice in the conical base of the cup, at 25°C. For further details, reference should be made to the Annual Book of ASTM Standards- Volume 06.01 , which is incorporated herein by reference in its entirety.

It is preferred that the aqueous composition be discharged from the distribution element in the form of droplets,^* and is most preferably discharged from the distribution element by centrifugal force. The distribution element is preferably rotary. The apparatus used for distributing the plant treatment agent in accordance with the present invention may be spraying equipment such as that manufactured by Nomix Manufacturing Co., Limited of Bristol, United Kingdom. An example of this type of spraying equipment is disclosed in British Patent Specification No. 2131327.

The low flow rate at which the aqueous composition is permitted to pass through the orifice is preferably in the range of from about 1 to about 300ml/min. More preferably, the low flow rate is from about 5 to about 100ml/min and most preferably, the low flow rate is from about 10 to about 40ml/min. Typically, the low flow rate is about 15ral/min.

The polymer is preferably a high molecular weight polymer such as a carboxyl vinyl polymer for example CARBOPOL (Registered Trade Mark of B.F. Goodrich Chemical Company) and should be present in an amount sufficient to stabilise the composition containing the aqueous plant treatment agent and to increase its viscosity from an initial lower flowability to a final higher desired flowability such that the time elapsed for 100ml of the composition to pass through the orifice of a Ford B2 cup lies in the range of from about 60 to about 100 seconds, preferably in the range of from about 75 to about 85 seconds. Thus, the polymer is preferably present in the composition in an amount no greater than about 2% by weight. Other polymers may be used including alginates, such as Kelgin (Registered Trade Mark) LV available from Kelco Corporation or equivalents thereof.

The aqueous composition of the second aspect of this invention and as used in the first aspect of the invention preferably further comprises a spreading agent. The spreading agent is preferably a mineral oil such as a non-aromatic spirit. Where a non-aromatic mineral spirit is used, it is preferably present in an amount of from about 1 to about 200 grams per litre of the composition, more preferably from about 10 to 80 grams per litre.

The aqueous composition of the second aspect of the present invention and as used in the method of the first aspect of the present invention may further comprise an emulsifier such as a nonylphenol-ethylene oxide condensate. Moreover, the aqueous composition may comprise a pigment such as titanium dioxide which may be present in an amount of from about 1 to about 50 grams per litre, more preferably from about 15 to about 25 grams per litre of the composition.

The term plant treatmen "agent as used herein includes pesticides such as herbicides, insecticides, fungicides, seed germination stimulants, plant growth regulators, mixtures of these and the like.

The plant treatment agent is preferably water soluble but it is to be appreciated that relatively water-insoluble plant treatment agents may be used. Thus, the aqueous composition may be a solution of the plant treatment agent, a suspension or emulsion thereof.

The plant treatment agent employed in the first and second aspects of the present invention is preferably a herbicidal agent, which is present in the composition in a herbicidally effective amount. The herbicide is preferably N-PMG or an agriculturally acceptable salt thereof or mixtures thereof which may be present in an amount such as to provide from about 40 to about 240 grams, preferably from about 60 to about 160 grams of the N-PMG or N-PMG equivalent per litre in the final composition. The plant treatment agent may, alternatively, for example, an oxadiazon or phenoxy type herbicide such as 2,4-D or N- [ (acetylamino)methyl]-2-chloro-N-(2,6- diethylphenyDacetamide. Appropriate herbicides are listed in The Pesticide Manual, published by the British Crop Protection Council, 7th edition; reference should also be made to the Farm Chemicals Handbook, 1988 Meister Publishing Co.. N-PMG is preferably used as the isopropylamine or trimethylsulphonium salt or as the free acid N-PMG; the trialkylsulphonium salt is disclosed and described in EP-0053871 and US-4315765 and other salts of N-PMG useful in the invention are described in EP- 0057317, EP-0054832, EP-0073547, which are incorporated herein by reference in their entirety. However, any agriculturally acceptable salt of N-PMG, or mixtures thereof, or mixtures of N-PMG and its agriculturally acceptable salts, may be employed. Other salts which may be useful in the invention are the iminourea and substituted iminourea salts such as guanidine and aminoguanidine salts. For more information as to the nature of acceptable N-PMG salts and also for further information concerning N-PMG generally, reference should be made to US Patents Nos. 3799758 and 4405531, which are incorporated herein by reference in their entirety.

The N-PMG is preferably used as an aqueous solution. One readily available aqueous solution of the isoproylamine salt of N-PMG is known by the

Registered Trade Mark ROUNDUP. ROUNDUP additionally includes a surfactant which is an exthoxylated fatty amine (a tallow amine) to the extent of about 15% by weight of the solution. An alternative solution of N- PMG is known by the Registered Trade Mark SPACER. In the present invention it is preferred that a ROUNDUP solution comprising 192 grams per litre of the isopropylamine salt be used: this is equivalent to 144 grams per litre of the free acid N-PMG.

Preferably, the mineral oil is a non-aromatic mineral spirit which is used to bring the surface tension of the composition to the desired level. The mineral oil is preferably present in amounts up to 200 g/litre, most preferably about 80 grams per litre of the final composition. The preferred carboxyl vinyl polymer is Carbopol ^R 1342 produced by B.F. Goodrich Chemical Company. This polymer is a fluffy white powder which is non-toxic.

The pigment is preferably titanium dioxide. This provides the formulation with a white appearance such that the user can determine fairly readily the areas to which the composition has been applied. Preferably, the pigment is used in amounts of up to 50, preferably up to 25 grams per litre of the final composition, most preferably about 18 grams per litre of the final composition. Without wishing to be bound by theory, it is currently believed that the polymer employed may assist in suspending the pigment in the composition.

In some embodiments of the present invention the composition may include a small amount of an emulsifier. The emulsifier is preferably a nonylphenol-ethylene oxide condensate, with the preferred emulsifier being Ethylan ^R 55 which is a nonylphenol-ethylene oxide condensate having, on average, 5.5 moles of ethylene oxide per mole of nonylphenol. Ethylan 55 is manufactured by Lankro Chemicals.

The emulsifier emulsifies the aqueous and organic phases of the composition.

According to a fourth aspect of the present invention there is provided an aqueous composition comprising a plant treatment agent and a viscosity modifying agent

In the composition of the fourth aspect of the invention, the plant treatment agent is preferably a herbicidal agent, present in a herbicidally effective amount. The herbicide is typically N-PMG or an agriculturally acceptable salt thereof.

The N-PMG or salt thereof may be present in an amount such as to provide from about 40 to about 80 grams of the free acid or free acid equivalent per litre in the composition.

The viscosity modifying agent may be a high molecular weight polymer such as a carboxyl vinyl polymer. The viscosity modifying agent may also be an alginate or other water soluble polymer. The composition may further comprise a spreading agent such as a mineral oil and/or a pigment such as titanium dioxide.

According to a fifth aspect of the present invention there is provided a process for producing an aqueous herbicidal composition which comprises preparing an aqueous solution or dispersion of the polymer; introducing into the polymer solution the plant treatment agent and optionally the mineral oil and mixing to form an intermediate composition; dispersing the pigment in the intermediate composition and optionally diluting with additional water to form the final product.

According to another process aspect of the invention, there is provided a process for producing an aqueous herbicidal composition, which process comprises: preparing an aqueous solution of a polymer; introducing into the aqueous solution of the polymer a mineral oil and the herbicide N- phosphonomethylglycine or an agriculturally acceptable salt thereof; and forming a premix of the aqueous mixture of polymer, mineral oil and herbicide; dispersing a pigment in the premix; and optionally diluting with water to form the final product.

According to yet another process aspect of this invention, there is provided a process for producing an aqueous herbicidal composition, which process comprises, preparing an aqueous solution of a polymer, introducing into the aqueous solution a pesticide and mixing an optionally diluting with additional water to form a final composition such that the final composition has a viscosity at 25°C such that the time taken for 100ml of the composition to pass through a measurement orifice of a Ford B2 cup is in the range of from about 60 to about 100 seconds.

It is believed to be important that the carboxyl vinyl polymer is^" thoroughly dissolved in water before

« any of the other ingredients are added. To this end, the polymer may be introduced into a volume of water and thoroughly.mixed for a period of up to twenty-four hours or longer. It may be desirable to heat the solution to enhance the dissolution of the polymer.

The polymer may be mixed with diluent water or a dilute solution of the plant treatment agents or herbicide. The polymer should be used in an amount of no greater that about 2% by weight.

The preferred process for making the composition of the present invention is as follows: (1 ) thoroughly dissolve the desired amount of carboxyl vinyl polymer, preferably carbopol 1342, in water to form an aqueous solution of polymer;

(ii) add the mineral oil to the aqueous solution of the polymer followed by addition of the aqueous solution of the plant treatment agent or herbicide to form a premix; (iii) disperse in the premix the pigment, preferably an aqueous suspension thereof; and

(iv) add the emulsifier, preferably Ethylan ^R 55, to form a concentration which may be diluted with water to the desired concentration.

The resulting composition may be diluted with water to obtain the desired concentration of the final composition.

The invention will now be illustrated by the following non-limiting Examples.

EXAMPLE 1 A composition was formulated using the following recipe:

400 millilitres per litre of a ROUNDUP solution comprising a 480 grams per litre aqueous solution of N- phosphonomethyl glycine (isopropylaraine salt);

100 millilitres per litre of a non-aromatic mineral spirit

18 grams per litre of titanium dioxide 3.5 grams per litre of carbopol 1342 2 millilitres of Ethylan 55.

The remainder of the composition is made up with water.

EXAMPLE 2 A composition was made using the following recipe: 158.68 grams Mon 0139 62.4% 28.85%

33.01 grams surfactant 6.00%

0.54 grams SAG 47 0.10%

1.67 grams Blazor red 0.30% 150.13 grams premix 27.29%

206.02 grams water 37.46%

Blazor red is a dye solution manufactured by Milliken. MON 0139 is a 62.4% by weight IPA salt of N- PMG. SAG 47 is a defoamer. The surfactant employed in this Example was an ethoglated tallow amine surfactant having a degree of ethoxylation of about 20. Components were added together in the order recited. Simple stirring was the only processing employed. The premix for this example comprised: 691.5 grams water 15.3 grams Kelgin LV (from Kelco)

The composition was employed to kill weeds.

Example 3 Another composition illustrating this invention was made and comprised: 76.4 lbs. water

100 grams SAG 47 93.3 lbs. premix a 10.1 lbs. premix b 18.8 lbs. surfactant 81.4 lbs. Mon 0139 62.4% weight IPA salt of NPMG

Overall this composition comprised: MON 0139 62.4% weight IPA salt of NPMG 29.05% Mon surfactant 6.71%

SAG 47 0.10% Proxel GXL 0.10%

Ti Pure 900 Titanium Dioxide 1.81%

Daxad 11G 0.07%

Sterox NJ 0.21%

Water 61.35% Premix A comprised the thickener premix 110 lbs. water 97.90%

153.4 grams Proxel GXL 0.03% 916.9 grams Kelgin LV 1.80% Premix B of this example comprised two batches which were first prepared and then combined to form premix B.

Premix B-1 2075 Grams water 300.06 grams Sterox NJ 109.58 grams Daxad 11G 28.7 grams Sterox NJ 205.15 grams water

29.0 grams SAG 47

Premix B-2 comprised :

1347.8 grams of Premix B-1 and 1356.6 grams Titanium dioxide TiPure 900

Premix B-3 comprised :

1387.0 grams Premix B-1 and

1400.8 grams of titanium dioxide TiPure 900

Premix B-2 and Premix B-3 were admixed together to form Premix b which was employed along with Premix a above to form the composition of this example. The composition was employed to kill weeds. DAXAD is a product of W. R. Grace and is a condensated naphthalene formaldehyde sulphonate; PROXEL GXL is a product of ICI and is an microbial; Sterox NJ is a product of Monsanto and is an ethoxylated nonylphenol. The surfactant used in this example was the same as that used in Example 2.

The compositions of the invention had a flowability such that 100ml passed through the measurement orifice of a Ford 62 cup in between 60 and 100 seconds.

It is to be appreciated that all of the compositions of the present invention may be formulated in ready to use form such as in a package in accordance with the third aspect of the present invention.

When practicing this invention, effective amounts of plant treatment agent are applied to above ground portions of plant or the desired target or locus thereof. The application of an effective amount of plant treatment agent is essential for the practice of the present invention. The exact amount of active plant treatment agent to be employed and to be applied is dependent upon the. response desired from the target plant or locus thereof as well as such other factors as the plant species, stage of development, etc.

It is believed that one skilled in the art can readily determine from the teachings of this specification including examples, the approximate application rate.

It is to be appreciated that, in the process of the present invention, the spreading agent such as a mineral oil may be added as a final step after the premix of (i) dissolved polymer and (ii) aqueous or suspended plant treatment agent have been combined.

Claims

r-5-CLAIMS :

1. An aqueous composition comprising (a) a plant treatment agent and/or mixtures thereof and (b) a polymer in an amount sufficient to increase the flowability of the aqueous composition to a flowability at 25°C such that the time elapsed for 100ml of the composition to pass through a measurement orifice of a Ford B2 cup is in the range of from about 60 to about 100 seconds.

2. A composition according to Claim 1, wherein the viscosity is such that the time elapsed for 100ml of the composition to pass through the measurement orifice of a Ford B2 cup is in the range of from 75 to 85 seconds.

3. A composition according to Claim 1 or 2, wherein the polymer is a high molecular weight polymer.

4. A composition according to Claim 1, 2 or 3, wherein the polymer is a carboxyl vinyl polymer.

5. A composition according to any preceding claim, wherein the polymer is present in the composition in an amount no greater than about 2% by weight.

6. A composition according to any preceding claim, further comprising a spreading agent.

7. A composition according to Claim 6, wherein the spreading agent is a mineral oil.

8. A composition according to Claim 7, wherein the mineral oil is a non-aromatic mineral oil.

9. A composition according to Claim 8, wherein the non-aromatic mineral oil is present in an amount of from about 1 to about 200 grams per litre.

10. A composition according to Claim 8, wherein the non-aromatic mineral oil is present in an amount of from about 10 to about 80 grams per litre.

11. A composition according to any preceding claim, further comprising an emulsifier.

12. A composition according to Claim 11, wherein the emulsifier is a nonylyphenol-ethylene oxide condensate.

13. A composition according to any preceding claim, further comprising a pigment.

14. A composition according to Claim 13, wherein the pigment is titanium dioxide.

15. A composition according to Claim 14, wherein the titanium dioxide is present in an amount of from about 1 to about 50 grams per litre.

16. A composition according to Claim 14, wherein the titanium dioxide is present in an amount of from about 15 to about 25 grams per litre.

17. A composition according to any preceding claim, wherein the plant treatment agent is a herbicidal agent, which is present in the composition in a herbicidally effective amount.

18. A composition according to Claim 17, wherein the herbicide is selected from N- phosphonomethylglycine, an agriculturally acceptable salt thereof and mixtures thereof.

19. A composition according to Claim 18, wherein the agriculturally acceptable salt is the isopropylamine salt or the trimethylsulphunium salt.

20. A composition according to Claim 17, 18 or 19, wherein the N-phosphonomethylglycine, or agriculturally acceptable salt thereof, is present in an amount such as to provide from about 40 to about 240 grams of the N-phosphonomethylglycine or N- phosphomethylglycine equivalent per litre.

21. A composition according to Claim 17, 18 or 19, wherein the N-phosphonomethylglycine or agriculturally acceptable salt thereof, is present in an amount such as to provide from about 60 to about 160 grams per litre

22. A method of distributing a plant treatment agent comprising:

(i) providing an aqueous composition according to any one of the preceding claim; and

(ii) passing said aqueous composition under low pressure through a restriction at a low flow rate to a distribution element from which the aqueous composition is released.

23. A method according to claim 22, wherein the distribution element is rotary.

24. A method according to Claim 22 or 23, wherein the aqueous composition is discharged in the form of droplets.

25. A method according to Claim 22, 23 or 24, wherein the aqueous composition is discharged from the distribution element by centrifugal force.

26. A method according to any one of Claims 22 to 25, wherein the low flow rate is in the range of from about 1 to about 300 ml/min.

27. A method according to any one of Claims 22 to 25, wherein the low flow rate is from about 5 to about

100 ml/min.

28. A method according to any one of Claims 22 to 25, wherein the low flow rate is from about 10 to about 40 ml/min.

29. An aqueous composition comprising a plant treatment agent and a viscosity modifying agent.

30. A composition according to Claim 29, wherein the plant treatment agent is a herbicidal agent, which is present in the composition in a herbicidally effective amount.

31. A composition according to Claim 29 or 30, wherein the herbicide is N-phosphonomethylglycine, or a salt thereof.

32. A composition according to claim 31, wherein the N-phosphonomethylglycine, or salt thereof, is present in an amount such as to provide from about 40 to about 80 grams of the free acid or free acid equivalent per litre in the final composition.

33. A composition according to any one of Claims 29 to 32, wherein the viscosity modifying agent is a high molecular weight polymer.

_.34. A composition according to Claim 33, wherein the high molecular weight polymer is a carboxyl vinyl polymer.

35. A composition according to Claim 34, wherein the viscosity modifying agent is an alginate.

36. A composition according to any one of Claims 29 to 35, further comprising a surfactant.

37. A composition according to Claim 36, wherein the surfactant is a mineral oil.

38. A composition according to any one of Claims 29 to 37, further comprising a pigment.

39. A composition according to Claim 38, wherein

*~ • the pigment is titanium dioxide.

40. A dispensing package for an aqueous composition, said package comprising a collapsible container which* is filled with an aqueous composition any one of Claims 1 to 21 or 29 to 39 and which has an opening means through which the composition may be dispensed.

41. A process for producing an aqueous herbicidal composition, which process comprises: preparing an aqueous solution of a polymer; introducing into the aqueous suspension of the polymer a mineral oil and a plant treatment agent; forming a premix of the aqueous mixture of polymer, mineral oil" and a plant treatment agent; dispersing a pigment in the premix; and optionally diluting the composition.

42. A process for producing an aqueous herbicidal composition which comprises preparing an aqueous solution or dispersion of the polymer; introducing into the polymer solution the plant treatment agent and optionally the mineral oil and mixing to form an intermediate composition; dispersing the pigment in the intermediate composition and optionally diluting with additional water to form the final product.

43. A process for producing an aqueous herbicidal composition, which process comprises, preparing an aqueous solution of a polymer, introducing into the aqueous solution a pesticide and mixing andoptionally diluting with additional water to form a final composition such that the final composition has a viscosity at 25°C such that the time taken for 100ml of the composition to pass through a measurement orifice of a Ford B2 cup is in the range of from about 60 to about 100 seconds.