Patent Application
20230240287
This invention relates to agrochemical compositions. More specifically, the invention relates to an aqueous agrochemical composition comprising an electrolytic agrochemical dissolved in an aqueous phase, and an agrochemical suspended in the aqueous phase.
Agrochemicals can be formulated as concentrates in a variety of different forms, including solid compositions such as wettable powders and granules, as well as liquid compositions such as emulsifiable concentrates. Liquid compositions offer advantages over solid compositions because they are more easily measured and poured, and when diluted with water typically leave fewer residues in any equipment that is used to prepare and apply the agrochemical.
For agrochemicals that are insoluble or not fully soluble in water, it is typical to prepare liquid compositions by dissolving the agrochemical in an organic water-immiscible solvent, such as an aromatic hydrocarbon or a more polar ester solvent. However, the use of organic solvents in preparing liquid compositions is oftentimes undesirable, both ecologically and from the standpoint of human safety. Therefore, where possible, it is preferable to minimise the amount of organic solvent in liquid agrochemical compositions. In addition, many agrochemicals are electrolytes, which, whilst water-soluble, have insufficient solubility in organic solvents to enable an organic solution to be formulated.
Aqueous liquid compositions of agrochemicals can be prepared. In the case of water-soluble agrochemicals, the agrochemical can be dissolved in the aqueous phase. If the agrochemical is not soluble in water, it can be suspended as solid particles or as liquid droplets (e.g. oil-in-water emulsion). To suspend particles or droplets it is necessary to incorporate an anti-settling system of some kind, typically a water-swellable clay (e.g. attapulgite) or a water soluble polymer (e.g. xanthan gum). The inventors have found that structured surfactants (i.e. surfactant phases which impart anti-settling characteristics to the aqueous phase) can be used to suspend particles and droplets. An advantage of using a structured surfactant to suspend an agrochemical is that the surfactants can also act as adjuvants. Surfactant adjuvants are frequently employed with agrochemicals, either by incorporation into the agrochemical formulation or as a ‘tank mix’ component with the agrochemical prior to application, improving the biological effectiveness of the agrochemical when it is applied. Adjuvants that are ‘built-in’ to the formulation can also reduce storage and transport costs. Where it is desirable to include more than one agrochemical in a liquid composition, one or more agrochemicals can be dissolved in the aqueous phase and one or more agrochemicals can be suspended in the aqueous phase.
In the case of aqueous liquid compositions, a problem arises if one wishes to include a suspended agrochemical and at the same time include an electrolyte agrochemical. The inventors have found that electrolyte agrochemicals tend to cause conventional suspending clays and polymers to become significantly less effective as anti-settling aids, with the reduction in suspension ability increasing as the concentration of dissolved electrolyte increases. The inventors found that some surfactant combinations can produce a suspending structure at low electrolyte concentrations (e.g. 10 wt. % electrolyte) but then fail if a high concentration of the electrolyte agrochemical is used. Thus, it is an object of this invention to solve this problem and provide aqueous agrochemical compositions which can accommodate a comparatively high concentration of electrolyte agrochemical while at the same time allow other agrochemicals to be suspended therein. It would be an advantage to be able to combine high concentrations of dissolved electrolyte agrochemicals with suspended solid or liquid agrochemicals in the presence of surfactants by selecting surfactants that ensure good suspension and pourability of the liquid formulation over the temperature range required for storage (typically −10° C. to 40° C.). Combinations of agrochemicals can give additive properties of each separate agrochemical and high concentration reduces packaging and transport costs. The incorporation of surfactant to suspend the solid or liquid agrochemical particles removes the need for other anti-settling aids which have little or no benefit to biological effectiveness when the product is applied.
The inventors have discovered a surfactant system that is capable of suspending agrochemicals in water and of giving good pourability over the temperature range required for storage (−10° C. to 40° C.), even in the presence of 20 wt. % or more of a dissolved electrolyte agrochemical based on the total weight of water in the composition.
In one aspect the invention provides an agrochemical composition comprising:
In another aspect the invention relates to the use of the surfactant system of the invention for suspending agrochemicals in an electrolyte agrochemical-containing water composition, wherein the total amount of electrolyte agrochemicals dissolved in the water is 20 wt. % or more based on the total weight of water in the liquid agrochemical composition, and wherein the surfactant system comprises (a) an alkylpolyglucoside surfactant, an alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant; and (b) a co-surfactant comprising an anionic head group and a tail group, wherein the tail group comprises at least two alkyl, alkenyl or alkynyl groups.
4.1 General Remarks
As used herein, the terms “comprises”, “comprising”, “includes”, “including”, “has”, “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a composition that comprises a list of components is not necessarily limited to only those components but may include other components that are not expressly listed or inherent to such a composition. That said, the terms “comprises”, “comprising”, “includes”, “including”, “has”, “having” or any other variation thereof also cover the disclosed embodiment having no further additional components (i.e. consisting of those components).
Also, the indefinite articles “a” and “an” preceding an element or component of the invention are intended to be non-restrictive regarding the number of instances (i.e. occurrences) of the element or component. Therefore “a” or “an” should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.
Further, when an aspect of the invention is described as being ‘preferred’, it should be understood that, subject to the appended claims, this preferred aspect of the invention can be combined with other preferred aspects of the invention as described herein.
4.2 Liquid Composition
The agrochemical composition of the invention is a liquid. The term “liquid” is used throughout this disclosure to mean that the composition or ingredient in question takes the form of a liquid at standard temperature and pressure. Liquid agrochemical compositions are well-known in the art. For examples of such, reference is made to the “Catalogue of pesticide formulation types and international coding system”, Technical Monograph No. 2, 7th Ed. Revised March 2017, CropLife International. Any of the liquid compositions that are disclosed therein in which at least one agrochemical is dissolved in an aqueous phase and at least one agrochemical is suspended in the aqueous phase can be used for the present invention. By way of example, the liquid composition can take the form of a capsule suspension (CS), and oil-in-water emulsion (EW), a suspension concentrate (SC), a suspension concentrate for direct application (SD), a suspo-emulsion (SE), a mixed formulation of CS and SE (ZE), or a mixed formulation of CS and EW (ZW).
The liquid composition of the present invention is aqueous. By “aqueous” is meant that water is present as the continuous phase of the composition. Other water-miscible liquid solvents may be present, provided that their combined weight is less than the total weight of water in the composition. Preferably a mixture of water and such water-miscible liquid solvents comprises 60 wt. % or more of water, more preferably 70 wt. % or more of water, still more preferably 80 wt. % or more of water and even more preferably 90 wt. % or more of water, based on the combined weight of water and water-miscible liquid solvents. In another embodiment, the composition comprises 20 wt. % or less of water-miscible solvents other than water in the continuous phase, more preferably 10 wt. % or less, and even more preferably 5 wt. % or less, based on the combined weight of water and water-miscible liquid solvents. In a preferred embodiment, water is the only solvent used in the continuous phase of the composition.
The total amount of water that is present in the composition is 30 wt. % or more based on the total weight of the liquid agrochemical composition, preferably 35 wt. % or more and most preferably 40 wt. % or more. Water is preferably present in the composition in an amount of 75 wt. % or less based on the total weight of the liquid agrochemical composition, more preferably 70 wt. % or less, still more preferably 65 wt. % or less, more preferably 60 wt. % or less, and most preferably 50 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferably ranges for the amount of water in the composition. Preferable ranges include 30 to 75 wt. %, 35 to 70 wt. %, 35 to 65 wt. %, 40 to 60 wt. % and 40 to 50 wt. %.
(ii) Electrolyte Agrochemical Dissolved in the Water
The term “electrolyte agrochemical” means an agrochemical that will form ions if it is dissolved in water at 20° C. The term “agrochemical” as used herein (including for the suspended agrochemical described later) means any chemical that can kill, repel or inhibit the growth or reproduction of unwanted organisms (“pests”), or any chemical which can protect or promote the healthy growth or reproduction of wanted organisms such as crops, ornamental plants, livestock and domestic animals, and which are useful in agriculture, horticulture, forestry, animal husbandry, water treatment and land management, e.g. for application to fields, crops, orchards, livestock, gardens, woodland, hedgerows, parks, industrial estates, construction sites, airports, roads, railways, rivers, lakes, ponds, canals, irrigation and drainage works.
The electrolyte agrochemical can be a pesticide such as a herbicide, a fungicide, or an insecticide. The electrolyte agrochemical can be a plant growth regulator, or a fertilizer such as a water-soluble inorganic fertilizer or a water-soluble organic fertilizer. For the purpose of the present invention, the electrolyte agrochemical is preferably a herbicide.
In the present invention, one or more electrolyte agrochemicals are dissolved in the water that is contained in the liquid agrochemical composition. The total amount of electrolyte agrochemicals dissolved in the water is 20 wt. % or more based on the total weight of water in the liquid agrochemical composition. One advantage of the present invention is that the liquid composition can accommodate a higher amount of electrolyte agrochemical while still providing a stable structured surfactant system to suspend other agrochemicals. For reasons of economy (e.g. reduced packaging; reduced storage and transport costs), the total amount of electrolyte agrochemical can be made as close to saturation as possible as this gives the highest concentration of the material in the formulation. If the composition is to be stored and/or used at reduced temperatures, appropriate consideration of the lower saturation at such temperatures should be taken into account to avoid undesirable precipitation. The total amount of electrolyte agrochemical dissolved in the water is preferably 30 wt. % or more (based on the total weight of water in the liquid agrochemical composition) and may be present in an amount of 40 wt. % or more, 50 wt. % or more or 60 wt. % or more. The upper limit for the total amount of electrolyte agrochemical dissolved in the water is limited only by the amount of the agrochemical that the water can dissolve for the system in question. The total amount of electrolyte agrochemical dissolved in the water is preferably 100 wt. % or less (based on the total weight of water in the liquid agrochemical composition) and may be present in an amount of 90 wt. % or less, 80 wt. % or less, or 70 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferable ranges for the total amount of electrolyte agrochemical based on the total weight of water in the liquid agrochemical composition. Exemplary ranges include 30 to 100 wt. %, 40 to 90 wt. %, 40 to 80 wt. %, 30 to 60 wt. %, and 40 to 60 wt. %. The wt. % amounts above refer to the electrolyte agrochemical per se and not to any other entity that it may be associated with (e.g. a base). By way of illustration, if glyphosate is added as glyphosate-potassium, the wt. % amounts above refer to glyphosate and not to the glyphosate potassium salt.
Among the water-soluble herbicides that form electrolyte solutions in water are those listed in the Pesticide Manual (British Crop Protection Council; 16th edition). Examples of such herbicides include: acifluorfen-sodium, aminopyralid-triisopropanolammonium, amitrole, ammonium sulfamate, asulam-sodium, bentazone-sodium, bilanifos-sodium, bispyrabac-sodium, sodium metaborate, bromacil-lithium, bromoxynil-potassium, sodium chloroacetate, agrochemically acceptable salts of clopyralid, 2,4-D-dimethylammonium, 2,4-D-triethanolammonium, 2,4-D-triisopropylammonium, 2,4-DB-dimethylammonium, 2,4-DB-sodium, 2,4-DB-potassium, dicamba diglycolamine salt, dicamba-dimethylammonium, dicamba-diethanolammonium, dicamba-isopropylammonium, dicamba-potassium, dicamba-sodium, dicamba-triethanolammonium, difenzoquat metilsulfate, diflufenzopyr-sodium, endothal-mono (N,N-dimethylalkylammonium), flupropanate-sodium, fomesafen-sodium, fosamine-ammonium, glufosinate-ammonium, glyphosate-isopropylammonium, glyphosate-potassium, glyphosate-sesquisodium, glyphosate diammonium, glyphosate dimethylammonium, glyphosate-ammonium, imazamox, imazamox-ammonium, imazapic-ammonium, imazapyr-isopropylammonium, imazaquin-ammonium, imazethapyr-ammonium, ioxynil-sodium, MCPA-sodium, MCPA-potassium, MCPA-dimethylammonium, MCPB-sodium, MCPB-potassium, mecoprop-sodium, mecoprop-potassium, mecoprop-P dimethylammonium, mecopropo-P-potassium, metam-sodium, metam-potassium, picloram-potassium, picloram-dimethylammonium, picloram-triethylammonium, picloram-triisopropylammonium, picloram-triethanolammonium, propoxycarbazone-sodium, pyrithiobac-sodium, sodium chlorate, triclopyr-triethylammonium, dichlorprop-potassium, dichlorprop-P-dimethylammonium, dichlorprop-P-potassium, dichlorprop-P-sodium and urea sulfate. Preferred water-soluble electrolyte herbicides are selected from the following list: 2,4-D-dimethylammonium; 2,4-D-triethanolammonium; 2,4-D-triisopropylammonium; 2,4-DB-dimethylammonium; 2,4-DB-sodium and potassium; dicamba diglycolamine salt; dicamba-dimethylammonium; dicamba-diethanolammonium; dicamba-isopropylammonium; dicamba-potassium; dicamba-sodium; dicamba-triethanolammonium; glufosinate-ammonium; glyphosate-isopropylammonium; glyphosate-potassium; glyphosate-sesquisodium; glyphosate diammonium; glyphosate dimethylammonium; glyphosate-ammonium; MCPA-sodium; MCPA-potassium; MCPA-dimethylammonium; MCPB-sodium; MCPB-potassium; dichlorprop-potassium; dichlorprop-P-dimethylammonium; dichlorprop-P-potassium; and dichlorprop-P-sodium.
The most preferred water-soluble electrolyte herbicides are glyphosate (N-(phosphonomethyl)glycine), glufosinate ((RS)-2-Amino-4-(hydroxy(methyl)phosphonoyl)-butanoic acid), 2,4-D ((2,4-Dichlorophenoxy)acetic acid), and dicamba (3,6-Dichloro-2-methoxybenzoic acid), and their agrochemically acceptable salts. The well-known and widely used broad spectrum glyphosate type of herbicides are N-phosphono-methyl-N-carboxyalkyl compounds, particularly N-phosphonomethyl glycines, usually as a water-soluble agrochemically acceptable salt, commonly alkali metal e.g. sodium or potassium or trimethylsulphonium, isopropylamine, ammonium, diammonium, dimethylamine or triethanolamine salt. The glufosinate type of herbicides are phosphinyl amino acids such as glufosinate [2-amino-4-(hydroxymethylphosphinyl) butanoic acid], particularly useful as the ammonium salt. For both the glyphosate and glufosinate types of herbicide, the main active component is present in aqueous solution as an anion (or overall negatively charged zwitterion). 2,4-D can be used as its dimethylamine or choline salt, and dicamba can be used as its diglycolamine, dimethlyammonium, isopropylamine, potassium or sodium salt. When the electrolyte agrochemical is glyphosate, or a salt thereof, it is preferably present in the composition in an amount of 20 to 40 wt. % glyphosate based on the total weight of the composition.
Among water-soluble fungicides and/or insecticides that form electrolyte solutions in water are those listed in the Pesticide Manual (British Crop Protection Council; 16th edition). Examples of such include: sodium or potassium bicarbonate, GY-81, metam-sodium, metam-potassium, and phosphonic acid.
Among water-soluble plant growth regulators that form electrolyte solutions in water are those listed in the Pesticide Manual (British Crop Protection Council; 16th edition). Examples of such plant growth regulators include: S-abscisic acid, aviglycine hydrochloride, chlormequat chloride, cloxyfonac-sodium, dichlorprop-potassium, dichlorprop-P-dimethylammonium, dichlorprop-P-potassium, dichlorprop-P-sodium, gibberellic acid, GA3, 4 or 7, maleic hydrazide potassium salt, mepiquat chloride, and sodium nitrophenolate. Preferred plant growth regulators include dikegulac-sodium, ammonium 1-naphthylacetic acid, sodium 1-naphthylacetic acid, and potassium 1-naphthylacetic acid.
Among water-soluble fertilisers that form electrolyte solutions in water are the common water soluble inorganic fertilizers that provide nutrients such as nitrogen, phosphorus, potassium or sulphur. Examples of such fertilizers include:
Other water soluble nutrient containing compounds (commonly identified as “micronutrients”) may also be included in the compositions e.g. to provide minor or trace nutrients to the formulation. Similarly, water soluble buffering and chelating agents such as ammonium and alkali metal citrates, gluconates, lactates, and polyacrylates may be included as part or all of the electrolyte component of the formulation.
Combinations of water-soluble electrolyte agrochemicals with other water-soluble electrolyte agrochemicals can be used in the invention and it is preferable to combine herbicide with herbicide, fungicide with fungicide, plant growth regulator with plant growth regulator, etc.). Suitable herbicide combinations include: acifluorfen-sodium with bentazone-sodium; clopyralid potassium with MCPA potassium; 2,4-D-dimethylammonium with MCPA-dimethylammonium; 2,4-D-triethanolammonium, with MCPA-sodium; 2,4-D-triisopropylammonium with MCPA-potassium; 2,4-DB-sodium with MCPA-sodium and/or MCPA-potassium; 2,4-DB-potassium with MCPA-sodium and/or MCPA-potassium; dicamba-potassium with glyphosate-potassium; diflufenzopyr-sodium with dicamba-sodium; glufosinate-ammonium with MCPA salts such as MCPA-sodium or MCPA-potassium; glufosinate-ammonium with dicamba-isopropylammonium; dicamba diglycolamine salt with glyphosate diammonium; dicamba-triethanolammonium with glyphosate-isopropylammonium; dicamba-dimethylammonium with glyphosate dimethylammonium; dicamba-diethanolammonium with glyphosate-diammonium; dicamba-sodium with glyphosate-sodium; dichlorprop-P-dimethylammonium with MCPA-dimethylammonium; glyphosate-isopropylammonium or glyphosate-isopropylamine with glufosinate-ammonium; imazaquin-ammonium with chlormequat chloride; ioxynil-sodium with mecoprop-sodium and/or MCPA-dimethylammonium; MCPA-sodium with other MCPA salts (e.g. MCPA-potassium or MCPA-dimethylammonium), 2,4-DB potassium, and/or 2,4-DB sodium; MCPA-potassium with other MCPA salts (e.g. MCPA sodium), 2,4-DB potassium, and/or and 2,4-DB sodium; MCPA-dimethylammonium with other MCPA salts (e.g. MCPA-sodium or MCPA-potassium); MCPB-sodium with MCPB-potassium; 2,4-DB dimethylammonium, and/or ioxynil-sodium; mecoprop-P dimethylammonium with dichlorprop-P-dimethylammonium and/or MCPA-dimethylammonium.
Suitable plant growth regulator combinations include: sodium 1-naphthylacetic acid with sodium nitrophenolate; or chlormequat chloride with imazaquin-ammonium. A suitable plant growth regulator and herbicide combination is sodium 1-naphthylacetic acid with 2,4-D-sodium. Other combinations of water-soluble electrolyte plant growth regulators and other water-soluble electrolyte agrochemicals include: dichlorprop-P-dimethylammonium with MCPA-dimethylammonium and/or mecoprop-P-dimethylammonium; and gibberellic acid GA4 with glufosinate-ammonium.
(iii) Surfactant System
The composition comprises a surfactant system which forms vesicles in the aqueous phase, preferably multilamellar vesicles (spherulites). These vesicles allow an agrochemical to be suspended in the composition by forming a close-packed structure that provides the liquid with the rheological properties required to suspend solid particles or liquid droplets. The surfactant system comprises (a) an alkylpolyglucoside surfactant, an alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant. The surfactant system further comprises (b) a co-surfactant having an anionic head group and a tail group, wherein the tail group has at least two alkyl, alkenyl or alkynyl groups. The present invention is based on the surprising discovery that a surfactant system based on a combination of (a) an alkylpolyglucoside surfactant, an alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant and (b) a co-surfactant having an anionic head group and a tail group having at least two alkyl, alkenyl or alkynyl groups will allow vesicles to be formed in the presence of a large amount of electrolyte agrochemical and that vesicles can suspend solid particles and liquid droplets when stored over a wide temperature range, typically from −10° C. to 40° C.
In surfactant systems of the prior art, typically, when a large amount of electrolytic agrochemical is dissolved in the aqueous system, it becomes difficult if not impossible to combine surfactants in a way that can suspend other components such as a second agrochemical. In the presence of a high amount of electrolyte, in most surfactant combinations the surfactant combination is wholly or partially insoluble and separates out from the aqueous solution on storage or the surfactant combination becomes completely soluble, forming micellar solution, which is incapable of suspending particles.
For example, US 2010/0160168 A1 describes a homogenous liquid agrochemical concentrate. The surfactant system used therein forms a microemulsion (hence the homogeneity) which, being not a structured surfactant system, is incapable of suspending e.g. solids in the composition. U.S. Pat. No. 10,091,994 B2 describes a surfactant, the salt of which is reported to retain activity of the surfactant while avoiding problems with gelation in the formulation. There is no indication in this document about which surfactant systems can be used to suspend e.g. solids in an aqueous formulation that contains a comparatively high amount of electrolyte agrochemical.
The problems discussed further above, and the problems in the prior art mentioned immediately above are overcome by using a surfactant system in accordance with the invention based on a combination of (a) an alkylpolyglucoside surfactant, an alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant and (b) a co-surfactant comprising an anionic head group and a tail group, wherein the tail group comprises at least two alkyl, alkenyl or alkynyl groups. The present invention is also advantageous in that the surfactants used are environmentally friendly, unlike surfactants used in the prior art such as the cationic hexadecylammonium chloride.
(a-1) Alkylpolyglucoside Surfactant
Alkylpolyglucosides are a group of substances consisting of a chain of rings of a sugar linked to each other with glucosidic bonds in which the last ring of the glucosidic chain is acetalized with an alcohol. Particularly preferred for this invention are alkylpolyglucosides of Formula (I):
H-(G)n—O—R Formula (I)
Alkyl polyglucosides are usually mixtures of alkyl monoglucoside (e.g. alkyl-α-D- and -β-D-glucopyranoside, optionally containing smaller amounts of -glucofuranoside), alkyl diglucosides (e.g.-isomaltosides, -maltosides etc.) and alkyl oligoglucosides (e.g.-maltotriosides, -tetraosides etc.). Preferred alkyl polyglucosides for the present invention are C4-18-alkyl polyglucosides (i.e. where R in Formula (I) above is a 4 to 18 alkyl group), more preferably C6-14-alkyl polyglucosides, and in particular C6-12-alkyl polyglucosides. The alkyl polyglucosides may have a degree of polymerization of from 1.2 to 1.9 (i.e. ‘n’ in Formula 1 is from 1.2 to 1.9). More preferred are C6-10-alkylpolyglucosides where ‘n’ is from 1.4 to 1.9. The alkyl polyglucosides preferably have a HLB value of 11.0 to 15.0, and may have a HLB value of 12.0 to 14.0.
The total amount of alkyl polyglucoside surfactant is preferably present in the composition in an amount of 1.0 wt. % or more based on the weight of the liquid agrochemical composition, more preferably 2.0 wt. % or more, still more preferably 3.0 wt. % or more and most preferably 3.5 wt. % or more. The total amount of alkyl polyglucoside surfactant is preferably present in the composition in an amount of 10.0 wt. % or less based on the weight of the liquid agrochemical composition and may be present in an amount of 8.0 wt. % or less, 6.0 wt. % or less or 4.0 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferable ranges for the amount of alkyl polyglucoside surfactant. Exemplary ranges include 1.0 to 10.0 wt. %, 2.0 to 8.0 wt. %, 3.0 to 6.0 wt. %, and 2.0 to 4.0 wt. %. When the electrolytic herbicide is glyphosate, or a salt thereof, the total amount of the alkyl polyglucoside surfactant is preferably present in an amount of 2.0 to 8.0 wt. % based on the weight of the liquid agrochemical composition, more preferably 3.5 to 6.0 wt. %. Commercial examples of alkylpolyglucoside surfactants include Agnique PG series (BASF), AL-2559 and AL-2575 (Croda).
(a-2) Alkyl Glucamide Ester Surfactant
Alkyl glucamide ester surfactants are a group of surfactants obtainable by combining glucamine with a fatty acid. Particularly preferred for this invention are alkyl glucamide ester surfactants of Formula (II) below:
In Formula II, Ra is a linear or branched C5 to C21 alkyl group or a C5-C21 alkenyl group and Rb is a C1-C4 alkyl group. In a preferred embodiment Ra is a C9 to C13 alkyl group. In a preferred embodiment Rb is a methyl group. In a still further preferred embodiment, Ra is a C9 to C13 alkyl group and Rb is a methyl group. In a further preferred embodiment Ra is a C11 alkyl group and Rb is a methyl group. Alkyl glucamide ester surfactants are available commercially (e.g. Synergen GA from Clariant).
The total amount of alkyl glucamide ester surfactant in the composition is preferably 1.0 wt. % or more based on the weight of the liquid agrochemical composition, more preferably 2.0 wt. % or more, still more preferably 3.0 wt. % or more and most preferably 3.5 wt. % or more. The total amount of alkyl glucamide ester surfactant in the composition is preferably 10.0 wt. % or less based on the weight of the liquid agrochemical composition, and may be 8.0 wt. % or less, 6.0 wt. % or less or 4.0 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferable ranges for the total amount of alkyl glucamide ester surfactant. Exemplary ranges include 1.0 to 10.0 wt. %, 2.0 to 8.0 wt. %, 3.0 to 6.0 wt. %, and 2.0 to 4.0 wt. %. When the electrolytic herbicide is glyphosate, or a salt thereof, the total amount of alkyl glucamide ester surfactant is preferably present in an amount of 2.0 to 8.0 wt. % based on the weight of the liquid agrochemical composition, more preferably 3.5 to 6.0 wt. %.
(a-3) Ethoxylated Fatty Alcohol Phosphate Ester
The ethoxylated fatty alcohol phosphate ester for use in the present invention preferably has a structure according to Formulae IIIa and/or IIIb below:
In Formula IIIa, M1 and M2 are a cation, preferably independently selected from H+, Na+, K+, or NH4+, n is an integer from 1 to 20, and R is a C6-C22 straight- or branched-chain alkyl or alkenyl group. In one embodiment, M1 and M2 are a cation, preferably independently selected from H+, Na+, or K+, n is an integer from 2 to 12, and R is a C8-C18 straight- or branched-chain alkyl or alkenyl group. In one embodiment, M1 and M2 are a cation, preferably independently selected from H+, Na+, or K+, n is an integer from 2 to 20, and R is a C8-C18 straight-chain alkenyl group. In one embodiment, M1 and M2 are a cation, preferably independently selected from H+, Na+, or K+, n is an integer from 2 to 20, and R is a C8-C18 straight- or branched-chain alkyl group.
In Formula IIIb, M is selected from H+, Na+, K+, or NH4+, n and m are independently an integer from 1 to 20, and R1 and R2 are independently a C6-C22 straight- or branched-chain alkyl or alkenyl group. In one embodiment, M is a cation, preferably selected from H+, Na+, or K+, n and m are independently an integer from 2 to 12, and R1 and R2 are independently a C8-C18 straight- or branched-chain alkyl or alkenyl group. In one embodiment, M is a cation, preferably selected from H+, Na+, or K+, n and m are independently an integer from 2 to 20, and R1 and R2 are independently a C8-C18 straight-chain alkenyl group. In one embodiment, M is a cation, preferably selected from H+, Na+, or K+, n and m are independently an integer from 2 to 20, and R1 and R2 are independently a C8-C18 straight- or branched-chain alkyl group.
The ethoxylated fatty alcohol phosphate ester for use in the present invention can be the monoester according to Formulae IIIa, the diester according to Formula IIIb, or a mixture of the monoester and diester. When used as a mixture, the ratio of monoester:diester is preferably in the range of from 1:20 to 20:1, more preferably in the range of from 1:10 to 10:1. The total amount of ethoxylated fatty alcohol phosphate ester according to Formula IIIa and Formula IIIb in the composition (whether used alone or as a mixture) is preferably 1.0 wt. % or more based on the weight of the liquid agrochemical composition, more preferably 2.0 wt. % or more, still more preferably 3.0 wt. % or more and most preferably 3.5 wt. % or more. The total amount of ethoxylated fatty alcohol phosphate ester according to Formula IIIa and Formula IIIb in the composition is preferably 10.0 wt. % or less based on the weight of the liquid agrochemical composition, and may be 8.0 wt. % or less, 6.0 wt. % or less or 4.0 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferable ranges for the total amount of ethoxylated fatty alcohol phosphate ester according to Formula IIIa and Formula IIIb in the composition. Exemplary ranges include 1.0 to 10.0 wt. %, 2.0 to 8.0 wt. %, 3.0 to 6.0 wt. %, and 2.0 to 4.0 wt. %. When the electrolytic herbicide is glyphosate, or a salt thereof, the total amount of ethoxylated fatty alcohol phosphate ester according to Formula IIIa and Formula IIIb in the composition is preferably 2.0 to 8.0 wt. % based on the weight of the liquid agrochemical composition, more preferably 3.5 to 6.0 wt. %.
Examples of alkoxylated fatty alcohol phosphate esters are phosphate esters of poly (preferably 2 to 30) ethoxylated (preferably C6 to C22) fatty alcohols such as ethoxylated (2 EO (EO means an ethylene oxide unit) oleyl alcohol phosphate ester (e.g. Empiphos® O3D, Huntsman), ethoxylated oleyl alcohol phosphate esters (e.g. Crodafos® CO series, Croda), ethoxylated (2-10 EO) ceto/stearyl alcohol phosphate esters (e.g. Crodafos® CS series, Croda), ethoxylated (4-6 EO) tridecyl alcohol phosphate esters (e.g. Crodafos® T series, Croda), ethoxylated (3-6 EO) fatty alcohol phosphate esters (e.g. Rhodafac® series, Solvay).
Of the three classes of co-surfactants (a-1), (a-2) and (a-3) described above, the alkylpolyglucoside surfactants are most preferable since it has been found that this surfactant class allows for the highest concentration of electrolyte agrochemical in the composition of the invention.
If the surfactant system comprises two or more of (a-1) an alkylpolyglucoside surfactant, (a-2) an alkyl glucamide ester surfactant and (a-3) an alkyl ethoxy phosphate ester surfactant, the total amount of these three classes of surfactants in the composition of the invention is preferably 1.0 wt. % or more based on the weight of the liquid agrochemical composition, more preferably 2.0 wt. % or more, still more preferably 3.0 wt. % or more and most preferably 3.5 wt. % or more. The total amount of these three classes of surfactants in the composition is preferably 10.0 wt. % or less based on the weight of the liquid agrochemical composition, and may be 8.0 wt. % or less, 6.0 wt. % or less or 4.0 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferable ranges for the total amount of these three classes of surfactants in the composition. Exemplary ranges include 1.0 to 10.0 wt. %, 2.0 to 8.0 wt. %, 3.0 to 6.0 wt. %, and 2.0 to 4.0 wt. %. When the electrolytic herbicide is glyphosate, or a salt thereof, the total amount of three classes of surfactants in the composition is preferably 2.0 to 8.0 wt. % based on the weight of the liquid agrochemical composition, more preferably 3.5 to 6.0 wt. %.
(b) Co-Surfactant Comprising an Anionic Head Group and at Least Two Alkyl, Alkenyl or Alkynyl Groups
The co-surfactant comprises an anionic head group and a tail group, wherein the tail group comprises at least two alkyl, alkenyl or alkynyl groups. The term “co-surfactant” means that the surfactant works together with the aforementioned alkylpolyglucoside surfactant, alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant, so as to form vesicles by which other agrochemicals can be suspended. The term “head group” in the present invention means a functional group, e.g., a functional group that includes one or more oxygen, nitrogen, sulfur, or phosphorus atoms. The head group is negatively charged when dissolved in water and can be positioned on any part of the molecule. The head group is the hydrophilic part of the molecule. Suitable head groups include, for example, sulfate, sulfonate, carboxylate and phosphate. The term “tail group” takes its ordinary meaning in the art and in the case of the present invention represents the hydrophobic part of the molecule. The “tail group” comprises at least two alkyl, alkenyl or alkynyl groups. Preferably, the at least two alkyl, alkenyl or alkynyl groups are selected from a C1 to C22 alkyl group, a C2-C22 alkenyl group, and a C2-C22 alkynyl group.
In a preferred embodiment, the co-surfactant can be represented by Formula 1 below.
In Formula 1, A represents an anionic head group. The anionic head group is preferably selected from —SO3M (sulfonate), —OSO3M (sulfate), —CO2M (carboxylate), and —OPO3M (phosphate), where M is a cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+. The co-surfactant can have two anionic head groups where M is a divalent cation such as Ca2+. Preferably M is not H+ so that the co-surfactant of the invention is a neutralized salt. This has the advantage that the anionic co-surfactant is more water-soluble, but less soluble in oil or high electrolyte solutions, thereby providing for better suspending properties.
In Formula 1, R1, R2 and R3 can be the same or different, and each is independently selected from hydrogen, a C1 to C22 alkyl group, a C2-C22 alkenyl group, or a C2-C22 alkynyl group, provided that at most only one of R1, R2 and R3 is H, and provided that the total number of carbons in R1 to R3 is 6 to 24.
In Formula 1, L represents a linking group that connects R1, R2 and R3 to the anionic head group by 7 or less atoms selected from C, N, O, S, and P, preferably 5 or less atoms. R1 to R3 can be but do not have to be bonded to the same atom in the linking group L. In a preferred embodiment, R1, R2 and R3 are separated from one another by at most 4 atoms. When counting the atoms that separate R1 to R3 from A, or R1 to R3 from one another, the shortest chain of covalently bonded atoms should be chosen, and only those atoms that are not part of A or R1 to R3 are counted. An example of how the degree of separation is to be counted is provided later with respect to Formula 3-2a and Formula 4-2a.
The co-surfactant to be used in the invention can also be represented by Formula 2-1 below. In Formula 2-1, A, R1, R2 and R3 are the same as described above for Formula 1. That is, A represents an anionic head group preferably selected from —SO3M (sulfonate), —OSO3M (sulfate), —CO2M (carboxylate), and —OPO3M (phosphate), where M is a cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+. R1, R2 and R3 can be the same or different, and each is independently selected from hydrogen, a C1 to C22 alkyl group, a C2-C22 alkenyl group, or a C2-C22 alkynyl group, provided that at most only one of R1, R2 and R3 is H, and provided that the total number of carbons in R1 to R3 is 6 to 24. Additionally, ‘p’ is selected from 0 or 1; ‘n’, ‘a’, ‘b’ and ‘c’ are the same or different, and are independently selected from 0, 1 or 2; and X1, X2 and X3 are the same or different and are independently selected from a direct bond, —O—, —COO—, —CH(OH)—, or —CONH—. In this case the degree of separation of A from R1 to R3, or R1 to R3 from one another, is limited only by the choice of variables for ‘p’, ‘n’, ‘a’, ‘b’, ‘c’ and X1 to X3. However, it is still preferred that A is separated from each of R1, R2 and R3 by 7 or less atoms, more preferably 5 or less atoms. It is also preferred that R1, R2 and R3 are separated from one another by at most 4 atoms.
In the case where one of R1, R2 and R3 is H, then the co-surfactant is preferably represented by Formula 2-2 below where A, X1, X2, R1, R2, ‘p’, ‘n’, ‘a’, and ‘b’ are the same as described above for Formula 2-1. Compounds of this formula are more environmentally friendly and are thus preferred.
In a preferred embodiment of Formula 2-1 and 2-2, A is —SO3M, where M is cation, for example H+, Na+, K+, NH4+, or NH3iPr+. In another preferred embodiment of Formula 2-1 and 2-2, ‘n’, ‘a’, ‘b’ and ‘c’ are all 0. In another preferred embodiment of Formula 2-1 and 2-2, X1, X2 and X3 are the same or different and are independently selected from a direct bond, —COO—, or —CONH—. In still another preferred embodiment of Formula 2-1 and 2-2, X1, X2 and X3 are all direct bonds. In another preferred embodiment of Formula 2-1 and 2-2, A is —SO3M, where M is cation, for example H+, Na+, K+, NH4+, or NH3iPr+, ‘n’, ‘a’, ‘b’ and ‘c’ are all 0, and X1, X2 and X3 are all direct bonds.
In the case where ‘p’ of Formula 2-1 or Formula 2-2 is 1, then the co-surfactant is preferably represented by Formula 3-1 or Formula 3-2 below where A, X1, X2, X3, R1, R2, and R3, are the same as described above for Formula 2-1 and Formula 2-2, respectively.
In the case where ‘p’ of Formula 2-1 or Formula 2-2 is 1, then the co-surfactant is more preferably represented by Formula 4-1 or Formula 4-2 below where A, R1, R2, and R3, are the same as described above for Formula 2-1 and Formula 2-2, respectively.
In the case where ‘p’ of Formula 2-1 or Formula 2-2 is 1, the substitution pattern on the benzene ring is not particularly limited but more preferably adopts a para-substitution pattern. The para-substituted pattern for Formulae 3-1, 3-2, 4-1, and 4-2 is depicted below.
In the case of Formula 4-2a, A is separated from each of R1 and R2 by five atoms (four on the phenyl ring, plus the secondary carbon). R1 and R2 are separated from one another by one atom (the secondary carbon). In the case of Formula 3-2a, if X1 is —COO— and X2 is a direct bond, then A is separated from R1 by seven atoms (four on the phenyl ring, plus the secondary carbon, plus C and 0 (note: the oxygen of C═O is not counted as it is not part of the chain linking A to R1 and R2)) and from R2 by five atoms (four on the phenyl ring, plus the secondary carbon). In this example, R1 and R2 are separated from one another by three atoms (C and 0 from X1 plus the secondary carbon).
The co-surfactant to be used in the invention can also be represented by Formula 5 below. In Formula 5, A, R1, R2 and R3 are the same as described above for Formula 1. Additionally, ‘a’, ‘b’ and ‘c’ are the same or different, and are independently selected from 0, 1 or 2; and X1, X2 and X3 are the same or different and are independently selected from a direct bond, —O—, —COO—, —CH(OH)—, or —CONH—. In a preferred embodiment of Formula 5, X1, X2 and X3 are the same or different and are independently selected from a direct bond, —COO—, or —CONH—. In this case the degree of separation of A from R1 to R3, or R1 to R3 from one another, is limited only by the choice of variables for ‘a’, ‘b’, ‘c’ and X1 to X3. However, it is still preferred that A is separated from each of R1, R2 and R3 by 7 or less atoms, more preferably 5 or less atoms. In this case it is also preferred that R1, R2 and R3 are separated from one another by at most 5 atoms, preferably by at most 4 atoms.
In the case where the co-surfactant is represented by Formula 5 and one of R1, R2 and R3 is H, the then the co-surfactant is preferably represented by Formula 5-1 below, more preferably Formula 5-2 below, and in each case A, X1, X2, R1, R2, ‘a’, and ‘b’ are the same as described above for Formula 5.
In the case where ‘p’ of Formula 2-1 or Formula 2-2 is 0, then the co-surfactant is represented by Formula 6-1 or Formula 6-2 below where A, X1, X2, X3, R1, R2, R3, ‘n’, ‘a’, ‘b’, and ‘c’ are the same as described above for Formula 2-1 and Formula 2-2, respectively.
In a preferred embodiment of Formula 6-1 and 6-2, A is —SO3M, where M is cation, for example H+, Na+, K+, NH4+, or NH3iPr+. In another preferred embodiment of Formula 6-1 and 6-2, ‘n’, ‘a’, ‘b’ and ‘c’ are all 0. In another preferred embodiment of Formula 6-1 and 6-2, X, X2 and X3are the same or different and are independently selected from a direct bond, —COO—, or —CONH—. In still another preferred embodiment of Formula 6-1 and 6-2, X1, X2 and X3 are all direct bonds. In another preferred embodiment of Formula 6-1 and 6-2, A is —SO3M, where M is cation, for example H+, Na+, K+, NH4+, or NH3iPr+, ‘n’, ‘a’, ‘b’ and ‘c’ are all 0, and X1, X2 and X3 are all direct bonds.
In a preferred embodiment, the co-surfactant is represented by Formula 7 below where A, X1, X2, R1, R2 and ‘a’ are as described above for Formula 2-1.
In a preferred embodiment of Formula 7, A is —SO3M, where M is cation, for example H+, Na+, K+, NH4+, or NH3iPr+. In another preferred embodiment of Formula 7, X1 and X2 are both —COO—(ester). In another preferred embodiment of Formula 7, X1 and X2 are both —direct bonds.
In another preferred embodiment of Formula 7, R1 and R2 are the same or different and are C1-C12 alkyl groups. In particularly preferred embodiment of Formula 7, A is —SO3M, ‘a’ is 0, X1 and X2 are both —COO— (ester), and R1 and R2 are the same or different and are C6-C10 alkyl groups, preferably both C8 alkyl groups. In another particularly preferred embodiment of Formula 7, A is —SO3M, ‘a’ is 0, X1 and X2 are both direct bonds, and R1 and R2 are the same or different and are C1-C12 alkyl groups, preferably C2 to C10 alkyl groups, provided that the sum number of carbons in R1 and R2 is 8 to 12.
The co-surfactant for use in the present invention can also be represented by Formula 8-1 below, preferably Formula 8-2, where in each case A, X1, X2, R1, R2, ‘n’, ‘a’, and ‘b’ are the same as described above for Formula 2-1.
In a preferred embodiment of Formula 8-1 and Formula 8-2, A is —SO3M, where M is cation, for example H+, Na+, K+, NH4+, or NH3iPr+. In a preferred embodiment of Formula 8-1, R1 and R2 are the same or different and are C1-C14 alkyl groups. In a preferred embodiment of Formula 8-1, one of X1 and X2 is —COO— (ester) and the other is a direct bond. In another preferred embodiment of Formula 8-1, ‘n’ is 1 and ‘a’ and ‘b’ are both 0. In particularly preferred embodiment of Formula 8-1, A is —SO3M, ‘n’ is 1 or 2, ‘a’ and ‘b’ are both 0, one of X1 and X2 is —COO— (ester) and the other is a direct bond. In a preferred embodiment of Formula 8-1, A is —SO3M and R1 and R2 are the same or different and are C1-C14 alkyl groups, preferably R1 is a C8-12 alkyl group and R2 is a C1-C4 alkyl group, more preferably R1 is a C11 alkyl group and R2 is Me. In a preferred embodiment of Formula 8-2, A is —SO3M, n is 1 or 2, and R1 and R2 are the same or different and are C1-C20 alkyl or alkenyl groups, preferably R1 is a C8-20 alkenyl group and R2 is a C1-C4 alkyl group. In another preferred embodiment of Formula 8-2, A is —SO3M, n is 2, and R1 and R2 are the same or different and are C1-C20 alkyl or alkenyl groups, preferably R1 is a C8-20 alkenyl group and R2 is a C1-C4 alkyl group, more preferably R1 is a C15 to C19 alkenyl group and R2 is Me.
The co-surfactant for use in the present invention can also be represented by Formula 9 below where M is cation, for example H+, Na+, K+, NH4+, NH3iPr+, or Ca2+, and ‘a’ and ‘b’ are the same or different and are selected to be an integer from 0 to 11, provided that a+b is from 7 to 11. If M is Ca2+, the surfactant has two of the anionic counterions depicted in Formula 9. A preferred embodiment of Formula 9 is where a+b is 9. Commercially available surfactants according to Formula 9 include Nansa® HS80S (Innospec) and Biosoft® 411-E (Stepan).
The co-surfactant for use in the present invention can also be represented by Formula 10 below where M is cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+, and ‘a’ and ‘b’ are the same or different and are selected to be an integer from 0 to 11, provided that a+b is from 9 to 16. A preferred embodiment of Formula 10 is where a+b is 11 to 14. A commercially available surfactant according to Formula 10 includes Hostapur® SAS93 (Clariant).
The co-surfactant for use in the present invention can also be represented by Formula 11 below where M is cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+, and R1 and R2 are the same or different and are selected to be a C6 to C10 straight chain alkyl group. A preferred embodiment of Formula 11 is where R1 and R2 are both a C8 straight chain alkyl group. A commercially available surfactant according to Formula 11 includes Aerosol® OT-100 (Cytec Solvay).
The co-surfactant for use in the present invention can also be represented by Formula 12 below where M is cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+, and R1 and R2 are the same or different and are selected to be a C1 to 16 straight chain alkyl group, provided that together R1 and R2 provide 6 to 18 carbon atoms. A preferred embodiment of Formula 12 is where R1 is a C1-C4 straight chain alkyl group and R2 is a C5 to C14 straight chain alkyl group. A more preferable embodiment of Formula 12 is where R1 is Me and R2 is a C5 to C14 straight chain alkyl group, preferably R2 is a C9 to C13 straight chain alkyl group, and most preferably a C11 straight chain alkyl group. Commercially available surfactants according to Formula 12 include Crodasinic® LS30, Crodasinic® MS30, and Crodasinic® O (Croda).
Suitable co-surfactants for use in the present invention also include those disclosed on pages 5 to 18 of WO 2017/100051 A1, the structures and contents of which are incorporate herein by reference.
The co-surfactant for use in the present invention can also be represented by Formula 13-1 or Formula 13-2 below, preferably a mixture of Formula 13-1 and 13-2, where M is cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+, ‘a’ and ‘b’ are the same or different and are selected to be an integer from 0 to 11, provided that a+b is from 9 to 14. A preferred embodiment of Formula 13-1 and 13-2 and mixtures thereof is where a+b is 11 to 13. A still further preferred embodiments is where a is from 6 to 8 and b is from 5 to 7. A still further preferred embodiments is where a is 7 and b is 6. Surfactants according to Formula 13-1 and 13-2 are described on pages 6 to 8 of WO 2017/100051 A1 and are available commercially from Shell under the Enordet™ mark.
The co-surfactant for use in the present invention can also be represented by Formula 14 below where M is cation, for example H+, Na+, K+, Ca2+, NH4+, or NH3iPr+, and R1 and R2 are the same or different and are selected to be a C1 to 20 straight chain alkyl or alkenyl groups, provided that together R1 and R2 provide 6 to 20 carbon atoms. A preferred embodiment of Formula 14 is where R1 is a C1-C4 straight chain alkyl group and R2 is a C5 to C19 straight chain alkyl or alkenyl group. A more preferable embodiment of Formula 12 is where R1 is Me and R2 is a C5 to C19 straight chain alkenyl group, preferably R2 is a C13 to C19 straight chain alkenyl group, and most preferably a C17 straight chain alkenyl group. A commercially available surfactant according to Formula 14 includes Adinol® OT-72 (Croda).
The total amount of co-surfactant (b), particularly as defined in any of the formulae above, is preferably 1.0 wt. % or more based on the weight of the liquid agrochemical composition, more preferably 2.0 wt. % or more, still more preferably 3.0 wt. % or more and most preferably 3.5 wt. % or more. The total amount of co-surfactant (b) is preferably 15.0 wt. % or less based on the weight of the liquid agrochemical composition and may be present in an amount of 10.0 wt. % or less, 7.5 wt. % or less or 5 wt. % or less. Any of the lower wt. % values can be combined with any of the upper wt. % values to provide preferable ranges for the amount of co-surfactant (b) in the liquid agrochemical composition. Exemplary ranges include 1.0 to 15.0 wt. %, 2.0 to 10.0 wt. %, 3.0 to 7.5 wt. %, and 3.0 to 5.0 wt. %. When the electrolytic herbicide is glyphosate, or a salt thereof, the total amount of co-surfactant (b) in the liquid agrochemical composition is preferably from 1.0 to 10.0 wt. % based on the weight of the liquid composition, more preferably 2.0 to 7.5 wt. %, even more preferably 3.0 to 5.0 wt. % based on the total weight of the composition.
The weight ratio of the total amount of alkyl polyglucoside surfactant (a) to the total amount of co-surfactant (b) is preferably 0.3 or more, more preferably 0.7 or more, still more preferably 1.0 or more and most preferably 1.1 or more in terms of improving stability. The weight ratio of the total amount of the aforementioned alkylpolyglucoside surfactant, alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant (a) to the total amount of co-surfactant (b) is preferably 3.0 or less, still more preferably 1.5 or less and most preferably 1.2 or less in terms of maintaining reduced viscosity (and hence better pouring ability). Any of the lower ratio values can be combined with any of the upper ratio values to provide preferable ranges for the ratio of the total amount of the aforementioned alkylpolyglucoside surfactant, alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant (a) to the total amount of co-surfactant (b). Exemplary ranges include 0.3 to 3.0, 0.7 to 1.5, 0.7 to 1.0, 1.0 to 1.2, and 1.0 to 1.5.
(iv) Agrochemical Suspended in the Liquid Composition
The liquid agrochemical composition of the invention comprises at least one agrochemical suspended in the composition. The suspended agrochemical is not particularly limited and may be any agrochemical that would be desirable to formulate together with the electrolyte agrochemical that is dissolved in the liquid composition. The suspended agrochemical may be in solid (e.g. as solid particles) or liquid form (e.g. as droplets of agrochemical or agrochemical dissolved in a water-immiscible liquid).
Examples of suitable agrochemicals that can be suspended in the liquid agrochemical composition of the invention include solid herbicides such as beflubutamid, benazolin, benzofenap, bifenox, bromobutide, chloridazon, chlorotoluron, chlorthal-dimethyl, cloransulam-methyl, desmedipham, diclosulam, esprocarb (or as capsule suspension), fentrazamide, flumetsulam, flurtamone, ioxynil, isoproturon, isouron, isoxaben, isoxaflutole, lenacil, linuron, mefenacet, metazachlor, metoxuron, metribuzin, oryzalin, oxadiargyl, oxadiazon, penoxsulam, pentoxazone, prodiamine, prometon, propyzamide, pyraflufen-ethyl, pyrazoxyfen, pyributicarb, pyriftalid, pyriminobac-methyl, pyroxsulam, quinclorac, quinmerac, trialkoxydim, simetryn, sulcotrione, sulfentrazone, terbuthylazine, terbutryn, and thenylchlor. Preferred solid herbicides include amidosulfuron, atrazine, azimsulfuron, bensulfuron-methyl, benzobicyclon, bromoxynil, butafenacil, chlorimuron-ethyl, chlorsulfuron, cinosulfuron, diflufenican, diuron, ethofumasate, ethoxysulfuron, flazasulfuron, florasulam, flucarbazone-sodium, flufenacet, foramsulfuron, flupyrsulfuron-methyl-sodium, halosulfuron-methyl, haloxyfop-P, imazapic, imazosulfuron, iodosulfuron-methyl-sodium, mesosulfuron-methyl, mesotrione, metamitron, metolachlor, S-metolachlor, metsulfuron-methyl, nicosulfuron, orthosulfamuron, oxasulfuron, pendimethalin, phenmedipham, picolinafen, primisulfuron-methyl, propachlor, prosulfuron, pyrazosulfuron-ethyl, quizalofop-P, rimsulfuron, saflufenacil, simazine, sulfometuron-methyl, sulfosulfuron, thifensulfuron-methyl, tribenuron-methyl, trifloxysulfuron, triflusulfuron-methyl, tritosulfuron.
Examples of suitable liquid herbicides that can be suspended in the liquid agrochemical composition include carfentrazone-ethyl and cinmethylin. Preferred liquid herbicides include acetochlor and butachlor.
In one embodiment of the invention, the electrolyte herbicide is glyphosate and the herbicide to be suspended is selected from any one of the herbicides mentioned above. In another embodiment of the invention, the electrolyte herbicide is glufosinate and the herbicide to be suspended is selected from any one of the herbicides mentioned above. In still another embodiment of the invention, the electrolyte herbicide is 2,4-D and the herbicide to be suspended is selected from any one of the herbicides mentioned above. In yet another embodiment of the invention, the electrolyte herbicide is dicamba and the herbicide to be suspended is selected from any one of the herbicides mentioned above.
Combinations of electrolyte herbicide to be dissolved in the liquid composition (first mentioned) and herbicide to be suspended in the liquid composition (second mentioned) include the following: dicamba-sodium and prosulfuron; dicamba-sodium and diflufenzopyr; glufosinate-ammonium and diuron; glufosinate-ammonium and simazine; glyphosate-isopropylammonium and florasulam; glyphosate-isopropylammonium and diuron; glyphosate-isopropylamine and diuron; glyphosate-potassium and diuron; glyphosate-sodium and diuron; glyphosate-potassium and pendimethalin; glufosinate-ammonium and saflufenacil; 2,4-D-dimethylammonium and florasulam; dicamba-potassium and saflufenacil; glyphosate-isopropylammonium and quizalofop-P; glyphosate-potassium and isoxaflutole; glyphosate-isopropylammonium and mesotrione; glyphosate-isopropylammonium and metolachlor; glufosinate-ammonium and pendimethalin; dicamba-potassium and atrazine; clopyralid and florasulam; glyphosate-isopropylammonium and acetochlor; glyphosate-isopropylammonium and metsulfuron-methyl; glyphosate-isopropylammonium and nicosulfuron; glyphosate-isopropylammonium and sulfosulfuron; dicamba-potassium and tribenuron-methyl, glyphosate-isopropylammonium and acetochlor. Combinations of electrolyte herbicide to be dissolved in the liquid composition (first mentioned) and two herbicides to be suspended in the liquid composition (second and third mentioned) include the following: glufosinate-ammonium with diuron and amitrole; glufosinate-ammonium with ethofumasate and phenmedipham; dicamba-potassium with atrazine and mesotrione; and dicamba-potassium with atrazine and S-metolachlor.
Examples of suitable safeners that can be suspended in the liquid agrochemical composition of the invention include those listed in the Pesticide Manual (British Crop Protection Council; 16th edition). Preferred herbicide safeners for use in the present invention include benoxacor, BCS (1-bromo-4-[(chloromethyl)sulfonyl]benzene), cloquintocet-methyl, cyometrinil, cyprosulfamide, dichlormid, dicyclonon, 2-(dichloromethyl)-2-methyl-1,3-dioxolane (MG 191), dietholate, fenchlorazole-ethyl, fenclorim, flurazole, fluxofenim, furilazole, isoxadifen-ethyl, jiecaowan, jiecaoxi, mefenpyr, mefenpyrethyl, methoxyphenone ((4-methoxy-3-methylphenyl)(3-methylphenyl)methanone), mephenate, naphthalic anhydride, oxabetrinil, AD67, mefenpyr-diethyl, R29148, TI-35, and MG191.
Examples of suitable plant growth regulators that can be suspended in the liquid agrochemical composition of the invention include 6-benzylaminopurine, cytokinins, prohexadione-calcium, paclobutrazol, sintofen, uniconazole, and cyclanilide.
Examples of suitable fungicides that can be suspended in the liquid agrochemical composition of the invention include azoxystrobin, coscalid, captan, carboxin, chlorothalonil, difenaconazole, cpoxiconazole, fenamidone, fludioxinil, fluopicolide, fluoxastrobin, flusilazole, folpet, ipconazole, mancozeb, mandipromid, metconazole, pencycuron, propiconazole, prothioconazole, pyrimethanil, sulfur, tebuconazole, tetraconazole, thibendazole, trifloxystrobin, triticonazole, zoxamide, benthiavalicarb-isopropyl, bitertanol, carpropamid, iprodione, kresoxim-methyl, maneb, metrafenone, picoxystrobin, spiroxamine, thifluzamide, thiophanate-methyl, thiram, tolclofos-methyl, and triadimenol. Combinations of electrolyte fungicide to be dissolved in the liquid composition (first mentioned) and other fungicide to be suspended in the liquid composition (second and optionally third mentioned) include the following: imazalil sulphate with pyrimethanil and pencycuron; propamocarb hydrochloride with fenamidone and fluopicolide; potassium bicarbonate with sulfur; and phosphonic acid with azoxystrobin.
Examples of suitable acaricide or insecticides that can be suspended in the liquid agrochemical composition of the invention include bifenazate, bifenthrin, bromopropylate, carbofuran, chromafenozide, clofentazine, alpha-cypermethrin, deltamethrin, dicofol, diflubenzuron, etofenprox, etoxazole, fipronil, imidachloprid, indoxacarb, metaflumizone, methiocarb, methoxyfenocide, novaluron, pyridalyl, pyrimethanil, quinoxyfen, spinosad, spirodiclofen, spiromesifen, spirotetramat, teflubenzuron, thiocloprid, and thiamethoxam.
(v) Other Components
In addition to the ingredients described in detail above, the liquid agrochemical composition of the invention may comprise one or more additional co-formulants such as other surfactants (e.g. emulsifiers and/or dispersants), polymeric amphoteric dispersants such as Atlox® 4915 to prevent or minimise flocculation of the suspended agrochemical, thickeners and thixotropic agents, wetting agents, anti-drift agents, adhesives, penetrants, preservatives, antifreeze agents (such as propylene glycol and glycerol), antioxidants, solubilizers, fillers, carriers, colorants (such as dyes), antifoams (such as silicone based agents), fertilizers, evaporation inhibitors and agents which modify pH and viscosity. Because the combination of the aforementioned alkylpolyglucoside surfactant, alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant (a) and a co-surfactant (b) comprising an anionic head group and a tail group, wherein the tail group comprises at least two alkyl, alkenyl or alkynyl groups is capable of suspending an agrochemical in the formulation, even in the presence of a large amount of electrolyte agrochemical, the present invention provides improved freedom to formulators to tailor the composition to particular needs. For instance, the present invention allows reduced amounts of thickeners and thixotropic agents thus leaving room for other adjuvants, such as one of those listed in the Compendium of Herbicide Adjuvants, 12th Edition, Southern Illinois University, 2014, or any earlier edition thereof. Examples of commonly used adjuvants include, but are not limited to, paraffin oil, horticultural spray oils (e.g., summer oil), methylated rape seed oil, methylated soybean oil, highly refined vegetable oil, polyol fatty acid esters, polyethoxylated esters, ethoxylated alcohols, alkyl polysaccharides and blends, amine ethoxylates, sorbitan fatty acid ester ethoxylates, polyethylene glycol esters, alkylpolyglucosides and their derivatives (e.g. esters), organosilicone based surfactants, ethylene vinyl acetate terpolymers, and ethoxylated alkyl aryl phosphate esters.
4.3 Method of Preparation
The liquid agrochemical composition of the invention can be prepared by known processes, for example, as will be described in more detail later, by first preparing a mill base of certain ingredients and a solution base of certain ingredients and then combining both by blending. So long as the final composition comprises the aforementioned alkylpolyglucoside surfactant, alkyl glucamide ester surfactant and/or an ethoxylated fatty alcohol phosphate ester surfactant (a) and the co-surfactant (b) comprising an anionic head group and a tail group, wherein the tail group comprises at least two alkyl, alkenyl or alkynyl groups, vesicles will form thus forming a solution-suspension of the two or more agrochemicals.
To prepare the mixtures, it is possible to use customary mixing apparatus which, if required, are thermostatted. For pre-grinding, it is possible to use, for example, high-pressure homogenizers or mills operating by the rotor-stator principle, such as Ultraturrax homogenizers, for example those from IKA, or toothed colloid mills, for example from Puck or Fryma. For fine grinding, it is possible to use, for example, bead mills which operate batchwise, for example from Drais, or bead mills which operate continuously, for example from Bachofen or Eiger.
5. Preferred Embodiments
A preferred embodiment of the liquid agrochemical composition according to the invention is one comprising:
H-(G)n—O—R Formula (I)
In this preferred embodiment the electrolyte agrochemical dissolved in the water is preferably selected from glyphosate-isopropylammonium, glyphosate-potassium, glyphosate-sesquisodium, glyphosate diammonium, glyphosate dimethylammonium, glyphosate-ammonium, and glufosinate ammonium. In another preferred embodiment the agrochemical suspended in the liquid composition is diuron. In a preferred embodiment the co-surfactant is represented by Formula 9 and the electrolyte agrochemical dissolved in the water is selected from glyphosate-isopropylammonium, glyphosate-potassium, glyphosate-sesquisodium, glyphosate diammonium, glyphosate dimethylammonium, glyphosate-ammonium, and glufosinate ammonium. In another preferred embodiment, the electrolyte agrochemical dissolved in the water is selected from glyphosate-isopropylammonium, glyphosate-potassium, glyphosate-sesquisodium, glyphosate diammonium, glyphosate dimethylammonium, glyphosate-ammonium, and glufosinate ammonium, the co-surfactant is represented by Formula 9, and the agrochemical suspended in the liquid composition is diuron.
Agrochemical compositions comprising a variety of test surfactants as a co-surfactant (b) to an alkylpolyglucoside surfactant (a) were prepared and tested for stability.
Preparation of a Mill Base
Being practically water-insoluble, the algicide and herbicide Diuron ((3-(3,4-dichlorophenyl)-1,1-dimethylurea) was chosen as being representative of the general class of agrochemicals that can be suspended in accordance with the present invention.
Water (48.98 wt. %), Silcolapse® 426R (0.82 wt. %), Agnique® PG-8107G (6.27 wt. %) and Diuron (43.93 wt. %) were added together and blended using a Silverson high shear mixer that was set at 3000 rpm with a small hole head. Agnique® PG-8107G (BASF AG) is an alkylpolyglucoside, representative of one class of surfactants that are required for the present invention. Silcolapse® 426R (Bluestar Silicones) is an anti-foamer and is added to reduce foaming during preparation and throughout the experiment. The obtained slurry was bead milled in an Eiger mill for approximately 40 minutes at 3000 rpm using 1-1.3 mm beads. The final particle size of the Diuron (D50: 1.9 μm; D90: 4.7 μm) was typical of that used for suspensions of agrochemical particles in aqueous formulations. It was observed by microscopy that the particles were well-dispersed in the millbase.
Preparation of Solution Base
Being a water-soluble electrolyte, the herbicide glyphosate was chosen as being representative of the general class of electrolyte agrochemicals that can be dissolved in the aqueous phase in accordance with the present invention.
Water (36.47 wt. %), Silcolapse® 426R (0.10 wt. %), Agnique® PG-8107G (5.66 wt. %), and 83.7% KOH (16.39 wt. %) were added together and stirred with an overhead mixer fitted with a propeller stirrer. Glyphosate (41.38 wt. %) was added slowly to the KOH solution and stirred for at least one hour to ensure complete neutralization and dissolution.
Preparation of the Agrochemical Compositions for Testing
Agrochemical compositions were prepared by blending the mill base as described previously (21.48 wt. %), water (2.57 wt. %), the surfactant to be tested (14.53 wt. % of a 30% aq. solution of surfactant) and the solution base as described previously (61.42 wt. %). After blending, agrochemical compositions were obtained having an electrolyte agrochemical (glyphosate) dissolved in an aqueous phase and having another agrochemical (Diuron) suspended in the aqueous phase. The relative amount of the different components in the compositions was as follows:
The compositions were stored for one week at 20° C. and then visually inspected for stability. The results for the different compositions comprising the different test surfactants are provided in the table below. The degree of separation is an estimate based on the amount of clear solution that separated from the otherwise opaque composition.
For the present experiments, good pourability was defined as <500 mPa-s at 20 sec−1; poor pourability is defined as >1000 mPa-s at 20 sec−1.
It is clear from the data in the table above that not all surfactants worked synergistically with the alkylpolyglucoside to provide a stable yet pourable composition in the presence of a significant amount of electrolyte agrochemical. For example, nonionic surfactants that are typically used in agrochemical compositions, such as alkoxylated fatty alcohols (Synperonic® A2; Synperonic® 13/6.5) and alkoxylated fatty amines (Adsee® AB615), as well as cationic surfactants such as those based on a quaternary ammonium (Arquad® 16-29), led to compositions that exhibited significant separation. It was also not sufficient for the surfactant to be amphoteric (Ammonyx® LO) or to be a zwitterion (Empigen® BB). While these were somewhat more stable than the non-ionic and cationic surfactants, they nevertheless suffered significant separation and also exhibited poor pourability.
From the data above it can be seen that the surfactants that lead to pourable compositions with little or no separation upon storage share common traits. First, they are all anionic surfactants having at least two hydrocarbon chains. Anionic surfactants having just one hydrocarbon chain led to compositions that were either not pourable (Empicol® LZ) or exhibited low pourability with significant separation (Steol® CS270). It is not enough for the surfactant to simply have two hydrocarbon chains. Surfactants having two hydrocarbon chains but which are not anionic led to compositions that were either not pourable (Polyaldo® 6-2-6) or exhibited poor pourability and/or significant separation (Polyaldo® 10-2-P; Polyaldo® 10-10-0).
An agrochemical composition was prepared with a significantly higher amount of electrolyte agrochemical and was tested for stability under different conditions. The table below provides a summary of the composition and the test results.
As can be seen from the data above, the combination of surfactants in accordance with the invention provides stable agrochemical compositions under various testing conditions. After storage, all samples were stable and exhibited good pourability. Good pourability is defined as <500 mPas at 20 sec−1.
An agrochemical composition was prepared in which a mixture of co-surfactants according to the invention were used. The table below provides a summary of the composition and the test results.
As can be seen from the data above, the combination of surfactants in accordance with the invention provides stable agrochemical compositions under various testing conditions. After storage, all samples were stable and exhibited good pourability. Good pourability is defined as <500 mPa·s at 20 sec−1.
An agrochemical composition was prepared in which the amount of co-surfactant was reduced. The table below provides a summary of the composition and the test results.
As can be seen from the data above, reducing the amount of co-surfactant still provides stable agrochemical compositions under various testing conditions. After storage, all samples were stable and exhibited good pourability. Good pourability is defined as <500 mPa·s at 20 sec−1.
An agrochemical composition was prepared in which a mixture of a co-surfactant according to the invention and another surfactant was used. The table below provides a summary of the composition and the test results.
As can be seen from the data above, while a surfactant such as sodium alkyl ethoxy 2EO sulphate (from Steol® CS270) was not by itself sufficient to provide a stable composition with an alkylpolyglucoside (see Example 1), it can nevertheless be added to the composition if a co-surfactant according to the invention is present.
This example tests if alkylpolyglucoside surfactants can be replaced with another electrolyte tolerant surfactant and retain stability. In this example the alkylpolyglucoside surfactant of the previous examples was replaced with a betaine surfactant (Empigen® BS). Betaines are a class of surfactant that are considered to have a greater electrolyte tolerance than ethoxylated surfactants, anionic surfactants and cationic surfactants on account that they are less likely to precipitate from a high-electrolyte composition than these other surfactants.
Preparation of a Mill Base
Water (21.75 wt. %), Silcolapse® 426R (0.82 wt. %), Empigen® BS (33.50 wt. % of a 30% aq. solution) and Diuron (43.93 wt. %) were added together and blended using a Silverson high shear mixer that was set at 3000 rpm with a small hole head. The obtained slurry was bead milled in an Eiger mill for approximately 13 minutes at 3000 rpm using 1-1.3 mm beads. The final particle size of the Diuron (D50: 2.2 μm; D90: 5.1 μm) was typical of that used for suspensions of agrochemical particles in aqueous formulations and the particles were well-dispersed in the millbase (as observed by microscopy).
Preparation of Solution Base
Water (35.53 wt. %), Silcolapse® 426R (0.10 wt. %), 30% aq. soln. of Empigen® BS (6.60 wt. %), and 83.7% KOH (16.39 wt. %) were added together and stirred with an overhead mixer fitted with a propeller stirrer. Glyphosate (41.38 wt. %) was added slowly to the KOH solution and stirred for at least one hour to ensure complete neutralization and dissolution.
Preparation of the Agrochemical Compositions for Testing
Agrochemical compositions were prepared by blending the mill base as described previously (21.48 wt. %), water (2.57 wt. %), Nansa® HS 80S (14.53 wt. % of a 30% aq. solution of surfactant) and the solution base as described previously (61.42 wt. %). After blending, an agrochemical composition was obtained as follows:
The composition was stored for one week at 20° C. and then visually inspected for stability and was estimated to give 40% separation. Comparing this data to the corresponding composition in Example 1 that used sodium dodecylbenzene sulphonate (from Nansa® HS80S) (stability at one week at 20° C.: <1% separation) makes it clear that the co-surfactant of the invention works synergistically with alkylpolyglucoside surfactants to provide stable compositions, even in the presence of electrolyte agrochemicals.
Agrochemical compositions were prepared in which the relative amount of alkylpolygluco side surfactant and co-surfactant is varied. The table below provides a summary of the compositions and the test results.
In this experiment the total amount of alkylpolygluco side surfactant and co-surfactant was kept constant (7.50 wt. %) but their relative amounts were varied. All samples had at least acceptable or good pourability and were stable. Good pourability is defined as <500 mPa·s at 20 sec−1; acceptable pourability is defined as 500-1000 mPa·s at 20 sec−1.
Agrochemical compositions were prepared largely in line with Example 1. The table below provides a summary of the compositions and the test results. The composition with the xanthan gum (Kelzan AP-AS) was designed to have as close as possible a viscosity as the composition of the invention before being sent for storage.
The composition of the invention exhibited good stability and pourability under all storage conditions. Good pourability is defined as <500 mPa-s at 20 sec−1. The composition with xanthan gum exhibited significant separation at 20° C. and 40° C. and poor pourability at −10° C.
Agrochemical compositions were prepared using glufosinate-ammonium instead of glyphosate. The table below provides a summary of the compositions and the test results.
As can be seen from the data above, the combination of surfactants in accordance with the invention provides stable agrochemical compositions under various testing conditions for a different electrolyte agrochemical (in this case glufosinate-ammonium). After storage, all samples were stable and exhibited good pourability. Good pourability is defined as <500 mPa·s at 20 sec−1.
An agrochemical composition was prepared but using an alkyl glucamide ester as the co-surfactant (a) instead of an alkylpolyglucoside. The table below provides a summary of the composition and the test results.
Alkyl glucamides are a class of surfactant that have been found to have a greater electrolyte tolerance than nonionic ethoxylated surfactants, ethoxylated anionic surfactants, non-ethoxylated anionic surfactants and cationic surfactants on account that they are less likely to precipitate from a high-electrolyte composition than these other surfactants.
The same millbase as was prepared in Example 1 was used, hence the trace amount of alkylpolyglucoside. A concentrated glyphosate solution was prepared including a C8, C10-alkyl sugar amide (i.e. the glucamide in Synergen GA). In the presence of the dissolved glyphosate, the glucamide and isopropylamine LABS formed a structure capable of suspending the milled diuron particles.
As can be seen from the data above, the agrochemical composition is stable under various testing conditions. After storage, all samples were stable and exhibited good pourability. Good pourability is defined as <500 mPa·s at 20 sec−1.
An agrochemical composition was prepared but using an ethoxylated fatty alcohol phosphate ester surfactant as the co-surfactant (a) instead of an alkylpolyglucoside. The table below provides a summary of the composition and the test results.
Ethoxylated fatty alcohol phosphate esters are a class of surfactant that have been found to have a greater electrolyte tolerance than nonionic ethoxylated surfactants and non-ethoxylated anionic surfactants and cationic surfactants on account that they are less likely to precipitate from a high-electrolyte composition than these other surfactants.
The same millbase as was prepared in Example 1 was used, hence the trace amount of alkylpolyglucoside. A concentrated glyphosate solution was prepared including a C10 EO4 phosphate ester (i.e. the phosphate ester in Multitrope 1214). In the presence of the dissolved glyphosate, the ethoxylated fatty alcohol phosphate ester and isopropylamine LABS formed a structure capable of suspending the milled diuron particles.
As can be seen from the data above, the agrochemical composition is stable under various testing conditions. After storage, all samples were stable and exhibited good pourability. Good pourability is defined as <500 mPa-s at 20 sec−1.
This example tests if the co-surfactant (a) of the present invention can be replaced with another surfactant (alkyl dimethylamine oxides) that is considered in the art to have equivalent electrolyte tolerance to alkyl polyglucosides. An agrochemical composition was prepared but using an alkyl dimethylamine oxide as the co-surfactant (a) instead of an alkylpolyglucoside. The table below provides a summary of the composition and the test results.
This example shows that an alkyl dimethylamine oxide cannot replace alkylpolyglucoside as the main soluble surfactant in the glyphosate electrolyte solution.
| Number | Date | Country | Kind |
|---|---|---|---|
| 18215405.4 | Dec 2018 | EP | regional |
| 19196194.5 | Sep 2019 | EP | regional |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 17416266 | Jun 2021 | US |
| Child | 18299317 | US |
