PRODIAMINE-COATED FERTILIZER AND METHOD OF MANUFACTURE

Abstract

An herbicidal concentrate composition that contains Prodiamine herbicide for application to a granular carrier such as a fertilizer granule, or a granule to be mixed with granular fertilizer.

Claims

1-12. (canceled)

13. A method of manufacture of a granular product coated with prodiamine, comprising a) providing a granular carrier, b) coating said carrier with a concentrate solution comprising between 15% and 60% by weight prodiamine and an aprotic solvent, and c) removing solvent to provide prodiamine-coated granules, wherein said granular prodiamine-coated granular product adapted for use in turf and is effective for weed control in turf and other non-agricultural sites.

14. The method of claim 13 wherein the aprotic solvent comprises n-octyl pyrrilidinone.

15. The method of claim 13 wherein the aprotic solvent comprises N,M-pyrrolidinone.

16. The method of claim 13 wherein the aprotic solvent comprises acetone.

17. The method of claim 13, wherein the concentrate solution further comprises a fatty acid dialkylamide solvent.

18. The method of claim 13, wherein the concentrate solution further comprises gamma-Butyrolactone

19. The method of claim 13, wherein the carrier comprises granular fertilizer.

20. The method of claim 13, wherein the concentrate further comprises one or more of an alkyl-alkoxylate-based emulsifier, a hydrophilic non-ionic emulsifier, a fatty acid benzene sulfonate.

21. The method of claim 13, wherein the concentrate further comprises an anionic emulsifier.

22. The method of claim 13 further comprising coating the granular product with an outer coating to improve flowability, hydroscopic properties, or to insulate the prodimine from incidental contact with a person applying the combination prodiamine product to turf.

23. The method of claim 13, wherein the concentrate further comprises fenoxaprop-p-ethyl, wherein the weight ratio of prodiamine to fenoxyprop is between 3:1 to 8:1.

24. The method of claim 13 further comprising coating the granular product with an outer coating to improve flowability, hydroscopic properties, or to insulate the prodimine from incidental contact with a person applying the combination prodiamine product to turf.

25. The method of claim 13, comprising coating the granular product with an outer coating.

26. A method of weed control comprising applying the granular product coated with prodiamine of claim 13 to turf.

27. A method of weed control comprising applying the granular product coated with prodiamine of claim 23 to turf.

Description

[0021] Embodiments of the invention relate to use of a non-aqueous solvent-based concentrate formulation for improved herbicidal protection applied to a carrier, which consists essentially of [0022] (a) 10 weight percent to 40 weight percent of Prodiamine active herbicidal ingredient; [0023] (b) optionally 1 weight percent to 60 weight percent of a fatty acid dialkylamide solvent; [0024] (c) 5 weight percent to 60 weight percent of a polar aprotic organic solvent, for example wherein the polar aprotic organic solvent consists of, consists essentially of, or comprises N,M-pyrrolidinone; and [0025] (d) optionally 1 weight percent to 12 weight percent of a surfactant, for example an alkyl-alkoxylate-based emulsifier, typically a alkyl-based EO-containing block copolymer emulsifier, for example an Ethylene oxide/Propylene oxide alkyl (e.g., butyl) block copolymer, a hydrophilic non-ionic emulsifier, typically a ethoxylated fatty alcohol, for example a tridecyl alcohol hydrophilic non-ionic emulsifier; and/or fatty acid benzene solfonate, particularly calcium salts of dodecylbenzenesulfonate.

[0026] Prodiamine is a selective herbicide having a formula N3,N3-di-n-propyl-2,4-dinitro-6-(trifluoromethyl)-m-phenylenediamine. Prodiamine is typically used as a pre-emergence herbicide for preferably season long control of grass and broadleaf weeds, including crabgrass. Prodiamine is typically used at application rates of between 0.25 and 1.5 lb ai/A (0.28-1.68 kg/ha), but typically it would be used at 0.5 to 1.0 lb ai/A (0.56-1.12 kg/ha).

[0027] We found alkyl pyrrolidinones, particularly N-methylpyrrolidinone (NMP), to be particularly useful to formulate a high-concentration prodiamine EC, that is, greater than 10% by weight active ingredient. Dimethylsulfoxide is useful, but has less than half the solubilizing ability as NMP. Use of DMSO in the absence of NPM will result in a practical limitation of less than 10% prodiamine in the EC. Other solubilizing solvents include fatty acid amide solvents such as N,N-dimethylcaprylamide (Cognis Agnique KE-3658) and N,N-dimethyloctanamide (Halcomid M8-10). These solvents are green, but use in the absence of NPM will result in a practical limitation of less than about 10% prodiamine.

[0028] The invention also relates to the use of such a solvent-based high prodiamine concentrate composition as an intermediate in manufacture of granular herbicide. Polar organic solvents such as N-methypyrrolidone (NMP), dimethylformamide (DMF) and dimethylsulfoxide (DMSO) have been used to impart good solubility properties prodiamine. Surprisingly, gamma-Butyrolactone also also shows solvating capacity near that of DMSO and the fatty amide solvents. Dimethylacetamide is expected to have good solvating properties but was not tested. Acetone can be useful because while it's flash point is low, giving a safety concern, this solvent is readily evaporated from the carrier. Dimethylformamide is also expected to have good solvating properties but use is highly restricted.

[0029] Accordingly, it is an object of the present invention to produce and utilize a stable, low phytotoxic concentrate formulation of prodiamine. We believe a concentrate utilizing one or more fatty amide solvents, e.g. an optionally alkylated C8 to C18 fatty amide, gamma-Butyrolactone, DMSO, or combination can provide a formulated concentrate with an acceptable amount of prodiamine, say 5% to 15%. NMP (CAS 872-50-4) provides superior solvating capacity, more than twice other solvents tested.

[0030] Embodiments of the invention relate to a concentrate formulation for improved herbicidal protection which consists essentially of [0031] (a) 10 weight percent to 30 weight percent of Prodiamine active herbicidal ingredient [0032] (b) 30 weight percent to 60 weight percent of a fatty acid dialkylamide solvent [0033] (c) 10 weight percent to 30 weight percent of a polar aprotic organic solvent [0034] (d) optionally 5 weight percent to 8 weight percent of an alkyl based block copolymer emulsifier; [0035] (e) optionally 2 weight percent to 5 weight percent of an trialkyl alcohol hydrophilic non-ionic emulsifier; and [0036] (f) optionally, up to 2 weight percent of an anionic emulsifier, and to the use of such an concentrate composition to form granular herbicide/fertilizer combinations.

[0037] An alternative concentrate formulation for use in manufacturing a granular herbicide is a concentrate which does not contain alkyl pyrrilodinones, for example an concentrate which consists essentially of [0038] (a) 10 weight percent to 40 weight percent of Prodiamine active herbicidal ingredient; [0039] (b) 30 weight percent to 60 weight percent of acetone; [0040] (c) 10 weight percent to 30 weight percent of a polar aprotic organic solvent selected from DMSO and gamma-Butyrolactone; [0041] (d) optionally 2 weight percent to 8 weight percent of an alkyl based block copolymer emulsifier; [0042] (e) optionally 2 weight percent to 8 weight percent of a trialkyl alcohol hydrophilic non-ionic emulsifier; and [0043] (f) optionally, up to 2 weight percent of an anionic emulsifier.

[0044] A preferred embodiment of the invention is a non-aqueous concentrate formulation for improved herbicidal protection which consists essentially of [0045] (a) 15 weight percent to 40 weight percent, preferably 20 to 30 weight percent, of Prodiamine active herbicidal ingredient; [0046] (b) 20 weight percent to about 60, for example 25 to 45, weight percent of N,M-pyrrolidinone; [0047] (c) optionally 1 weight percent to 50, for example 5 to 30 weight percent, of a fatty acid dialkylamide solvent; [0048] (d) optionally 2 weight percent to 6 weight percent of an alkyl based block copolymer emulsifier; [0049] (e) optionally 1 weight percent to 5 weight percent of an trialkyl alcohol hydrophilic non-ionic emulsifier; [0050] (f) optionally 0.1 to 2 weight percent of an anionic emulsifier such as a alkyl sulfonate or alkyl aryl sulfonate.

[0051] A preferred embodiment of the invention is use of a non-aqueous concentrate formulation for improved herbicidal protection which consists essentially of [0052] (a) 15 weight percent to 40 weight percent of Prodiamine active herbicidal ingredient; [0053] (b) 25 to about 60 weight percent of N,M-pyrrolidinone; [0054] (c) optionally 40 to 50 weight percent, of a fatty acid dialkylamide solvent.
This embodiment shows excellent stability.

[0055] Generally, the term consists essentially of means there are no other herbicidal active ingredients in the concentrate.

[0056] Fenoxaprop p-ethyl (we often refer to the herbicide as fenoxaprop) is a postemergence graminicide used on cool-season turfgrasses to control crabgrass and other annual grass weeds. It is known to mix fenoxaprop-p-ethyl with prodiamine, providing quick anti-crabgrass effect of fenoxyprop-p-ethyl with long term preemegence effect of prodiamine. Fenoxaprop is best provided to the foliage, so if prodiamine and fenoxyprop are both coating the granule, advantageously the fenoxaprop-p-ethyl is released from the granule immediately on application off sufficient water. In the above formulations, fenoxaprop-p-ethyl can replace some of the prodiamine, for example an amount of fenoxaprop wherein the weight ratio of prodiamine to fenoxyprop is in the range of 3:1 to about 8:1, more preferably about 4:1 to about 6:1, for example about 5:1. Alternatively fenoxyprop can be added to a low density carrier and admixed into the fertilizer, as fenoxyprop has foliar activity.

[0057] An alternative embodiment of the invention relates to application onto a carrier of a non-aqueous concentrate formulation for improved herbicidal protection which consists essentially of [0058] (a) 10 weight percent to 33 weight percent, preferably 12 weight percent to 30 weight percent, more preferably between 15 weight percent to 25 weight percent weight percent of Prodiamine (99.4% active) herbicidal ingredient; [0059] (b) 2 weight percent to 10 weight percent, preferably 3 weight percent to 8 weight percent, more preferably between 3 weight percent to 6 weight percent weight percent of fenoxaprop-p-ethyl (98.5% active, fenoxyprop) herbicidal ingredient; [0060] (c) 20 weight percent to 70 weight percent of a solvent selected from fatty acid dialkylamide solvents, gamma-butyrolactone, polar aprotic solvents, or mixtures thereof; [0061] (d) and optionally 0.5 to 10 percent by weight of surfactants, starches, and the like.

[0062] The material is primarily intended as a once-per-season treatment of turf to control crabgrass. Generally, the weight ratio of prodiamine to fenoxyprop is in the range of 3:1 to about 8:1, more preferably about 4:1 to about 6:1, for example about 5:1. There must be sufficient fenoxyprop to effect a kill on existing crabgrass. The application timing and conditions of applying these herbicides are known in the art, and best efficacy of fenoxaprop is obtained by early application (before three tiller stage) and to well watered turf. Too much prodiamine, or too late an application of the herbicide, and the preemergent herbicide may interfere with fall over-seeding programs.

[0063] All percentages and the term w/w used herein unless specifically stated are percent by weight, and all component amounts recited as parts are parts by weight and are usually on a basis of parts per part of the active ingredient. The term ppm is parts per million by weight. When salts of components are mentioned, unless otherwise specifically stated, the composition can contain the acid form of the component, one or more salts of the component, or any mixture thereof.

[0064] The aprotic solvent is preferably a pyrrolidone such as NMP, though one or more of dimethylsulfoxide (DMSO), dimethylformamide, and gamma-Butyrolactone alone or in mixtures, including mixtures with NMP, are useful. Various useful and incidental solvents are shown below, with the measured solubility of each of the active ingredients. The units for solubility below are grams of active ingredient per gram of respective solvent. All measurements were based on physical clarity and were performed at 22 degrees C.

TABLE-US-00001 Fenoxaprop- Solvent Prodiamine p-ethyl N-methyl pyrrolidinone (NMP) 0.68 1.04 Dimethylsulfoxide (DMSO) 0.24 0.72 Aromatic 150 (Aromatic Naphtha Hydrocarbon) 0.08 0.36 Aromatic 200 (Aromatic Naphtha Hydrocarbon) 0.07 0.24 Glycol Ether EB (Diethylene glycol 0.02 0.12 monubutyl ether) Carbitol TM (Diethylene glycom 0.01 0.12 monomethyl ether) Jefsol 1555 Proprietary Solvent (Carbonate) 0.004 <0.12 Glycol DPM (Dipropylene glycol methyl ether) 0.008 <0.12 Halcomid M8-10 (fatty acid 0.24 0.36 dialkylamide solvent) Exxol D110 (Paraffin Hydrocarbon) <0.02 <0.04 Agnique KE-3658 (fatty acid 0.24 0.36 dialkylamide solvent) BLO (Gamma-Butyrolactone) 0.25 0.58 DEGEE (Diethylene glycol monoethyl ether) 0.05 0.08

[0065] It can be seen that each polar aprotic solvent, NMP and DMSO, provide reasonable solubility, though NMP is far and away the superior solvent.

[0066] Fatty amides, also called fatty acid solvents in this application, are amides formed from a fatty acid and an amine, of which many are known. Preferred are di-substituted fatty acid amides, which include as non-limiting examples N,N-dimethylcaprylamide (available from Cognis as Agnique KE-3658), and N,N-diethyloctanamide (available as Halcomid M8-10). These compounds can fully or partially replace aprotic solvents, and the solvating capacity approaches that of less-preferred aprotic solvents such as DMSO and gamma-Butyrolactone, that is, 0.24 to 0.25 grams prodiamine per gram solvent. A mixture of C8 and C10 fatty acid dimethylamide, (CAS 1118-92-9 and 14433-76-2) are useful.

[0067] The alkyl-alkoxylate-based emulsifier is typically an alkyl-based EO/PO-containing block copolymer emulsifier, for example an Ethylene oxide/Propylene oxide alkyl (e.g., butyl) block copolymer. It is possible to use suitable co-polymers of ethylene oxide and propylene oxide, such as ABA or BAB block copolymer or BA block copolymers. The alkyl group can range from C3 to C7, for example. A preferred group of ethylene oxide/propylene oxide block copolymers for use in the compositions of this invention are butyl based poly(oxypropylene)poly(oxyethylene) block copolymers having an average molecular weight in a range of 2,400 to 3,500 (e.g. TOXIMUL 8320, Stepan Chemical Co.) Also useful is Harcros TDA-12.

[0068] The hydrophilic non-ionic emulsifier can be an ethoxylated alcohol. A C9 to C18 alcohol can be used, with for example 8 to 20 EO units, for example a tridecyl alcohol hydrophilic non-ionic emulsifier. Examples include Makon TD-12, a tridecyl alcohol ethoxylate, POE-12 available from Stepan, or Harcros TDA-12.

[0069] Generally an anionic emulsifier can provide added emulsion stability, and alkyl sulfonates are useful for this purpose, for example a fatty acid benzene sulfonate, particularly calcium salts of dodecylbenzenesulfonate.