Novel surfactants and formulations

Abstract

A herbicidal composition is provided comprising an aqueous solution of N-phosphonomethylglycine, predominantly in the form of the potassium salt thereof, at a concentration of at least 300 g a.e. / l of the composition; and a surfactant component in solution or stable suspension, emulsion, or dispersion in the water, comprising one or more surfactants in a total amount of about 20 to about 300 g / l of the composition, wherein the composition has a viscosity of less than about 250 centipoise at 0° C. or a Gardner color value less than 10.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This is a divisional of application Ser. No. 09 / 926,521, filed Apr. 26, 2002, which is a 371 U.S. National Application of PCT / US01 / 16550, filed May 21, 2001, which claims the benefit of U.S. Provisional Application Ser. No. 60 / 205,524, filed May 19, 2000, U.S. Provisional Application Ser. No. 60 / 206,628, filed May 24, 2000, U.S. Provisional Application Ser. No. 60 / 273,234, filed Mar. 2, 2001 and U.S. Provisional Application Ser. No. 60 / 274,368, filed Mar. 8, 2001.FIELD OF THE INVENTION [0002] The present invention relates to aqueous pesticide formulations containing high concentrations of a herbicide, such as the potassium salt of glyphosate, together with surfactants or other adjuvants, including formulations which form anisotropic aggregates (AA) or liquid crystals (LC) on or in the foliage of a plant. More specifically, the present invention relates to glyphosate containing herbicidal formulations containing one or more surfactants t...

AI Technical Summary

Benefits of technology

[0033] The present invention provides novel surfactants for formulating pesticide compositions such as aqueous herbicidal concentrates containing glyphosate or a salt or ester thereof. It has also been discovered that certain surfactants previously unknown for use in agriculture enhance herbicidal efficacy while remaining compatible with the glyphosate after prolonged storage.

[0034] One embodiment of the invention is directed to an aqueous herbicidal concentrate composition comprising glyphosate, predominantly in the form of the potassium salt thereof, in solution in an amount of in excess of 300 grams acid equivalent per liter of the composition, and a surfactant component in solution or stable suspension, emulsion or dispersion, comprising one or more surfactants in a total amount of about 20 to about 300 grams per liter of the composition. The composition either (a) has a viscosity of less than about 250 centipoise at 0° C. at 45 / s shear rate, (b) has a Gardner color value of not more than 14 when free of dye or a coloring agent, (c) has a viscosity less than a similarly loaded glyphosate potassium salt composition comprising an alkylpolyglycoside surfactant in combination with an alkoxylated alkylamine surfactant, said alkylpolyglycoside and alkylamine surfactants being present in a weight ratio between about 5:1 and 1:1, (d) controls velvetleaf growth as compared to such a similarly loaded glyphosate potassium salt composition, (e) contains a surfactant component that includes no effective amount of an alkylpolyglycoside and is selected such that the composition remains substantially homogeneous when stored at 50° C. for about 14 to 28 days, or (f) includes a surfactant component that contains an effective amount of alkylpolyglycoside in combination with at least one additional surfactant that contains no effective amount of an alkoxylated alkylamine.

[0035] Another embodiment of the invention is directed to such a glyphosate concentrate having a viscosity of less than about 250 centipoise at 0° C. at 45 / s shear rate, in which the surfactant component comprises one or more amine or quaternary ammonium salt compounds. Each of the compounds includes an alkyl or aryl substituent having from about 4 to about 16 carbon atoms and not more than ten ethylene oxide linkages within the compound. The compounds are present in an amount which enhances the compatibility of the surfactant component with the glyphosate salt.

[0036] The invention is also directed to formulations which form anisotropic aggregates comprised of a surfactant on the waxy cuticle of the foliage of the plant upon which the formulation is applied. Other herbicidal formulations of the present invention form liquid crystals comprised of the surfactant on the waxy cuticle of the foliage of the plant upon which the formulation is applied. Still other herbicidal formulations of the present invention form liquid crystals comprised of the surfactant on the waxy cuticle of the foliage and inside the plant upon which the formulation is applied. It has been found that the formation of anisotropic aggregates and both epicuticular and intracuticular liquid crystals do not depend on the presence or absence of a second surfactant and significantly enhance the performance of the herbicidal formulations of the present invention.

Problems solved by technology

Beyond some broad generalizations, the relative ability of different surfactants to enhance the herbicidal effectiveness of glyphosate is highly unpredictable.

It is likely that serious consideration of glyphosate potassium salt as a herbicidal active ingredient has been inhibited by the relative difficulty in formulating this salt as a highly concentrated SL product together with preferred surfactant types.

Such an increase in the viscosity of these high-strength formulations is undesirable for various reasons.

In addition to being more difficult to conveniently pour from the container or to wash residues therefrom, the deleterious effects resulting from higher viscosity formulations is more dramatically observed with respect to pumping requirements.

Products at lower a.e. concentration, i.e., more dilute, are also sold in some markets, but carry a cost penalty per unit of glyphosate they contain, primarily reflecting packaging, shipping and warehousing costs.

At very high glyphosate a.e. concentrations such as these, a significant problem normally occurs.

This is the difficulty in pouring and / or pumping of the aqueous concentrate arising from the high viscosity of the concentrate, especially as manifested at low temperatures.

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