Fatty acid-based herbicide composition

Abstract

A herbicide composition having an acidic pH, the composition comprising water, C6-C 12 fatty acids, alcohol alkoxylates, hydrophobic liquids, pH-sensitive hydrogel-forming polymers, and fumed silica.

Description

Technical Field

[0001] The present invention generally relates to the fields of horticulture, agriculture, and the control of unwanted plant growth. In particular, the present invention relates to fatty acid-based herbicide compositions, methods for their preparation, and their use and application for killing plants or retarding plant growth. Background Art

[0002] In home gardening and commercial agriculture, the use of herbicides to control unwanted plant growth is common. Herbicides are also commonly used to control unwanted plant growth around infrastructure such as public facilities.

[0003] Although beneficial (if not essential) in modern horticulture / agriculture and infrastructure maintenance, a major drawback of many currently used herbicides is that they are generally toxic to humans, animals, and the environment.

[0004] Glyphosate (N-(phosphonomethyl)glycine) is a widely used broad-spectrum systemic herbicide and plant desiccant. Although an effective herbicide, its widespread use has led to glyphosate tolerance in the field. In addition, there is increasing evidence that its use is having harmful effects on the environment and human health. As a result, there are now growing movements worldwide to ban the use of glyphosate-based herbicide compositions.

[0005] Alternative and more environmentally friendly herbicide compositions are known. For example, compositions containing fatty acids have been shown to exhibit herbicidal activity. It has been found that the active fatty acid components in such compositions decompose into relatively non-toxic residues quite rapidly after application. Thus, as an active herbicidal component, fatty acids show promise. However, when used at recommended doses, conventional fatty acid-based herbicide compositions generally require relatively high concentrations of fatty acids to promote acceptable herbicidal activity. For example, the application dose of such conventional compositions is typically at least 30 kg / ha of fatty acids. Conventional fatty acid-based herbicide compositions also often require frequent applications to achieve effective plant control. The need for higher active ingredient concentrations and more frequent applications can make the use of such herbicide compositions economically unattractive. Although fatty acids have fewer environmental problems compared to other herbicidal active ingredients (due to being naturally occurring and biodegradable), there are at least economic barriers to their use at relatively high concentrations to achieve the desired herbicidal effect even without environmental concerns.

[0006] Therefore, there remains an opportunity to develop fatty acid-based herbicide compositions with improved efficacy, especially where the fatty acid component can be effectively used at lower dosage ratios and still prove effective. Summary of the Invention

[0007] The present invention provides a herbicide composition having an acidic pH, the composition comprising water, C6-C12 Fatty acids, alcohol alkoxylates, hydrophobic liquids, pH-sensitive hydrogel-forming polymers, and fumed silica, wherein the pH of the composition does not promote hydrogel formation of the pH-sensitive hydrogel-forming polymer.

[0008] The present invention also provides a method for preparing a herbicide composition, the method comprising:

[0009] Providing an aqueous silica-containing composition comprising water, fumed silica, and a pH-sensitive hydrogel-forming polymer;

[0010] Combining the aqueous silica-containing composition with an alcohol alkoxylate to form a liquid alcohol-alkoxylate-containing composition; and

[0011] Combining the liquid alcohol-alkoxylate-containing composition with C6-C 12 Fatty acids and a hydrophobic liquid to produce the herbicide composition;

[0012] Wherein the herbicide composition so formed has an acidic pH that does not promote hydrogel formation of the pH-sensitive hydrogel-forming polymer.

[0013] The present invention further provides a herbicide composition produced by the method according to the present invention.

[0014] The present invention also provides a method for killing plants or retarding their growth, the method comprising contacting the plants with a herbicide composition according to the present invention.

[0015] The present invention further includes controlling plant growth at a site, the method comprising applying a herbicide composition according to the present invention to the site.

[0016] The present invention also provides the use of a herbicide composition according to the present invention for killing plants or retarding their growth.

[0017] The present invention further provides the use of a herbicide composition according to the present invention for controlling plant growth at a site.

[0018] Surprisingly, it has been found that the herbicide composition according to the present invention exhibits improved herbicidal activity relative to conventional fatty acid-based herbicide compositions, particularly in terms of requiring lower dose rates and fewer application frequencies.

[0019] Notably, unlike conventional fatty acid-based herbicide compositions, those according to the present invention can exhibit excellent herbicidal activity at fatty acid concentrations as low as 1 or 2 wt%. For example, the herbicide composition according to the present invention can be advantageously used effectively at a dose rate of about 15 kg / ha of fatty acid.

[0020] Of course, the herbicidal composition according to the present invention also exhibits excellent herbicidal activity at high fatty acid concentrations, but particularly surprisingly and advantageously, its efficacy at low fatty acid concentrations.

[0021] Without wishing to be bound by theory, the improved herbicidal activity of the composition according to the present invention is believed to be produced by the unique combination of the constituent components of the composition. Specifically, in addition to fatty acids, the constituent components of the composition are believed to act as adjuvants to effectively enhance the herbicidal activity of the fatty acid component and make it more readily bioavailable.

[0022] Similarly, without wishing to be bound by theory, the C6-C 12 fatty acid component of the herbicidal composition according to the present invention is believed to promote the so-called "burning" of plant tissue in much the same way as conventional herbicidal compositions are used. However, it has surprisingly been found that the adjuvant components used in the composition according to the present invention enhance the delivery and efficacy of the fatty acid component, such that lower concentrations of fatty acids can be used while still achieving excellent herbicidal activity.

[0023] This adjuvant component in the composition (i.e., water, alcohol alkoxylates, hydrophobic liquids, pH-sensitive hydrogel-forming polymers, and fumed silica) is believed to provide an effective vehicle for delivering the fatty acid component to the plant surface and enhancing the plant's absorption of the fatty acid component, with these adjuvant components together at an acidic pH that does not promote the hydrogel formation of the pH-sensitive hydrogel-forming polymer. The adjuvant components are believed to act alone and / or together in one or more ways to enhance the delivery of the fatty acid component.

[0024] For example, alcohol alkoxylates are believed to act at least in promoting the stability of the composition (as a concentrate or ready-to-spray composition) before application to the plant, and also in enhancing the adhesion of the composition to the plant surface during application.

[0025] Hydrophobic liquids are believed to at least minimize the loss of the composition from the plant surface during application, and / or contribute to the removal / destruction of the waxy cuticular coating on the plant surface to facilitate drying and / or delivery of the fatty acid component to the plant tissue.

[0026] At the acidic pH of the composition, the pH-sensitive hydrogel-forming polymer itself does not exist in the form of a hydrogel and imparts a limited increase in the viscosity of the herbicide composition, making it easy to apply, for example, by spraying. However, when the herbicide composition is applied to plants having at least alkaline sap, it is believed that the pH-sensitive hydrogel-forming polymer transforms into a hydrogel, thereby increasing the viscosity of its surrounding environment and greatly disrupting the stability of plant metabolism. This is believed to in turn make the plant more susceptible to the fatty acid component. Using a pH-sensitive hydrogel-forming polymer during at least part of the manufacture of the herbicide composition to produce a hydrogel also helps to promote a high degree of dispersion of fumed silica in the final composition.

[0027] The fumed silica component of the composition is believed to enhance the transport of the components of the herbicide composition into plant tissue. Providing fumed silica in a well-dispersed form in the herbicide composition is believed to be important for enhancing the transport of the components of the herbicide composition into plant tissue.

[0028] Overall, it has surprisingly been found that all the constituent components of the composition act synergistically and enhance the herbicidal efficacy of the fatty acid-based herbicide composition.

[0029] The types of constituent components in the herbicide composition according to the present invention and the relatively low concentrations of these components typically used in practice make the composition more economical and environmentally acceptable.

[0030] Other aspects and embodiments of the present invention will be discussed in more detail below. Detailed Description

[0031] The present invention provides a herbicide composition. As used herein, the term "herbicide" is intended to take its conventional meaning and define a composition comprising one or more constituent components capable of killing plants or retarding plant growth. The application of a herbicide will typically be used to kill one or more undesirable plant species, such as one or more weeds, or retard their growth. Thus, the expression "herbicidal activity" refers to the potential or realized function of the composition as a herbicide to kill plants or retard plant growth.

[0032] As will be discussed in more detail, the herbicide composition according to the present invention has an acidic pH. A composition having an acidic pH means that the pH of the composition is less than 7.

[0033] The herbicide composition according to the present invention can be classified as a non-selective herbicide. In context, the term "non-selective" refers to a broad spectrum of plant species against which the herbicide is active, and a non-selective herbicide is active against most, if not all, plant species.

[0034] Common plant species against which the herbicidal composition according to the present invention exhibits herbicidal activity include, but are not limited to, annual broadleaf weeds (such as Solanum nigrum, capeweed, burr medic, creeping oxalis, milk thistle, spear thistle, wireweed, pigweed, fat hen, shepherd's purse, algae, lichens, liverworts, mosses) and annual grasses (such as annual ryegrass), perennial broadleaf weeds (such as flatweed, hair hawkbit, lamb's tongue, dandelion, evening primrose, bell vine, white clover) and perennial grasses (such as couch grass, kikuyu, lovegrass, paspalum, volunteer wheat and perennial ryegrass).

[0035] The herbicidal composition according to the present invention is liquid-based and can be conveniently applied to the target plants or sites using conventional liquid-based herbicide application methods. Such application methods include, but are not limited to, spraying, irrigation or painting application.

[0036] The herbicidal composition according to the present invention is generally used as a post-emergence (i.e., directly applied to plants) herbicide.

[0037] The herbicidal composition according to the present invention is generally applied to contact at least some parts of the plant structure above the ground. For example, the composition can be applied to the plant foliage and / or stem structure.

[0038] The herbicidal composition is used in the amounts and concentrations of the constituent components to achieve the desired herbicidal activity. The desired herbicidal activity can be to kill the plants or just retard their growth. If necessary, the desired herbicidal activity can be achieved by applying the herbicidal composition to the plants or sites multiple times.

[0039] As will be understood by those skilled in the art, the amounts and concentrations of the constituent components in the herbicidal composition to be used in a given application will vary depending on many factors such as the plant species and the desired herbicidal activity result (i.e., for killing the plants or just retarding their growth). Taking into account the teachings herein, those skilled in the art will be able to easily select the amounts and concentrations of the constituent components in the herbicidal composition to be used in a given application.

[0040] The herbicidal composition according to the invention can advantageously be provided in concentrated form, which depending on the intended application can be used directly or diluted with water. For example, the concentrated form of the composition can be used on hardwood plants such as blackberries or lantanas by pouring it into the root area or applying it directly to freshly cut stems, or the concentrated form can be diluted with water for spraying, for example, on broadleaf weeds or grasses.

[0041] Unless otherwise stated, the expression "wt%" as used herein is intended to mean the weight percentage of a specific component relative to the total weight of all components present in the herbicidal composition.

[0042] According to the invention, the herbicidal composition has an acidic pH. Having an acidic or acidic pH means a pH less than 7. In contrast, referring to a basic or basic pH means a pH greater than 7.

[0043] Typically, the pH range of the herbicidal composition will be from about 2 to about 5, or from about 3 to about 4.

[0044] As will be discussed in more detail below, the herbicidal composition according to the invention includes a pH-sensitive hydrogel-forming polymer. Furthermore, the acidic pH does not promote the hydrogel formation of the pH-sensitive hydrogel-forming polymer. On the contrary, in order for the hydrogel formation of the pH-sensitive hydrogel-forming polymer to occur, it is necessary to make the pH of the composition more basic (i.e., shift towards the basic direction). Without wishing to be bound by theory, it is believed that at the acidic pH of the composition, the hydrogel-forming polymer will exist in a non-ionized form and thus does not form a hydrogel by itself. However, as the pH of the composition increases towards the basic pH, the pH-sensitive hydrogel-forming polymer becomes ionized, which in turn promotes the swelling and formation of the hydrogel. The formation of the hydrogel can significantly increase the viscosity of the composition and / or the liquid environment in which the composition is located.

[0045] Since the herbicidal composition according to the invention has an acidic pH that does not promote the hydrogel formation of the pH-sensitive hydrogel-forming polymer, the hydrogel-forming polymer exists in its non-hydrogel state, and thus the polymer has a limited or no viscosity-increasing effect on the composition. Therefore, the acidic form of the composition enables it to be easily applied using conventional techniques such as spraying application.

[0046] The acidity of the composition is typically provided by one or more of the constituent components of the composition. For example, a fatty acid component and / or a pH-sensitive hydrogel-forming polymer can provide the acidic pH of the composition.

[0047] Alternatively, one or more additional components can be included in the composition, and the one or more additional components provide or help provide the acidic pH of the composition. Such additional components can include, but are not limited to, hydrochloric acid and acetic acid.

[0048] In one embodiment, the composition according to the invention comprises acetic acid.

[0049] As long as the herbicide composition according to the invention is maintained at an acidic pH that does not promote the formation of pH-sensitive hydrogel-forming polymers, the composition may include one or more additives for adjusting the pH. For example, the composition may include conventional buffers and / or bases such as alkali metal hydroxides (e.g., sodium hydroxide).

[0050] Adjusting the pH of the herbicide composition can be helpful in the method of preparing the composition. Further details related to this method are outlined below.

[0051] In one embodiment, sodium hydroxide is used as a reagent for adjusting the pH during the manufacture of the herbicide composition.

[0052] In yet another embodiment, the herbicide composition according to the invention does not include potassium hydroxide.

[0053] The herbicide composition according to the invention comprises water. In one embodiment, the water is demineralized water.

[0054] The amount of water present typically varies from about 0.1 wt% to about 98 wt%.

[0055] The less water the composition contains, of course, the more concentrated it is. The concentration of the composition will typically be tailored for a given application.

[0056] When referred to as a concentrate, the herbicide composition typically comprises less than about 10 wt%, or less than about 7 wt%, or less than about 5 wt%, or less than about 2 wt% water.

[0057] In one embodiment, water is present in the herbicide composition in an amount of less than about 10 wt%, or less than about 7 wt%, or less than about 5 wt%, or less than about 2 wt% water.

[0058] In another embodiment, water is present in the herbicide composition in an amount in the range of about 0.1 wt% to about 10 wt%, or about 0.1 wt% to about 7 wt%, or about 0.1 wt% to about 5 wt%, or about 2 wt% to about 10 wt%, or about 2 wt% to about 7 wt%, or about 2 wt% to about 5 wt%.

[0059] As will be discussed below, the herbicide composition is typically manufactured in concentrate form and then optionally diluted with water for subsequent use.

[0060] Depending on the intended application, a concentrate form having about 2 wt% water can be diluted with additional water at a ratio of concentrate to water of, for example, 1:5, 1:10, 1:15, 1:20, 1:25, 1:30 or even up to 1:40 to provide, for example, a working spray composition.

[0061] When referred to as a working spray composition, the herbicide composition typically comprises at least about 50 wt%, or at least about 70 wt%, or at least about 80 wt% water.

[0062] In another embodiment, water is present in the herbicide composition in an amount in the range of about 50 wt% to about 98 wt%, or about 70 wt% to about 98 wt%, or about 80 wt% to about 98 wt%, or about 85 wt% to about 95 wt%.

[0063] In preparing such a working spray composition, some of the water used to dilute the concentrated composition can be replaced with acetic acid. For example, the working spray composition according to the present invention can comprise about 1 wt% to about 6 wt% acetic acid.

[0064] In one embodiment, the herbicide composition produced by the method according to the present invention is combined with water and acetic acid to provide a ready-to-use herbicide composition having an acidic pH that forms a hydrogel without promoting the formation of a pH-sensitive hydrogel-forming polymer.

[0065] The herbicide composition being provided in a "ready-to-use" form means that the herbicide composition can be used in application without any further alteration. In other words, the herbicide composition provides its constituent components at a concentration suitable for direct application.

[0066] The herbicide composition according to the present invention comprises C6-C 12 fatty acids. A fatty acid referred to as "C6-C12" means that it will contain 6 to 12 carbon atoms. The fatty acid can be saturated, unsaturated, straight-chain or branched-chain.

[0067] The fatty acid component of the composition is a key active herbicide.

[0068] In one embodiment, the fatty acid is a straight-chain fatty acid.

[0069] "Fatty acid" is intended to mean that a carbon chain or "fatty" component is covalently linked to a carboxylic acid, where the carboxylic acid is in its protonated form (i.e., not in the form of a salt).

[0070] Referring to C6-C 12The fatty acids are in their carboxylic acid form and those skilled in the art will understand that it will have only limited solubility in the aqueous component of the herbicidal composition. In other words, the fatty acid component is present mainly as the oil phase of the emulsion in the composition. Further details regarding emulsion stability will be discussed below.

[0071] However, those skilled in the art will understand that although C6-C12 fatty acids have very low solubility in water, their high surface activity can still contribute to the acidity of the herbicidal composition. That being said, those skilled in the art will also understand that as the carbon chain length of the fatty acids exceeds C12, their solubility in water decreases significantly and such higher fatty acids have little effect on the pH of the aqueous system.

[0072] In one embodiment, the C6-C 12 fatty acids are selected from caproic acid, enanthic acid, caprylic acid, pelargonic acid (also known as nonanoic acid), capric acid, undecylic acid, lauric acid, and sebacic acid.

[0073] In another embodiment, the fatty acids are selected from C8-C 12 fatty acids.

[0074] In yet another embodiment, the C6-C 12 fatty acid is pelargonic acid.

[0075] C6-C 12 fatty acids are generally present in the herbicidal composition in an amount in the range of from about 1 wt% to about 60 wt%.

[0076] When referred to as a concentrate, the herbicidal composition generally comprises greater than about 30 wt%, or greater than about 40 wt%, or greater than about 50 wt% of C6-C 12 fatty acids.

[0077] In one embodiment, C6-C 12 fatty acids are present in the herbicidal composition in an amount greater than about 30 wt%, or greater than about 40 wt% or greater than about 50 wt%.

[0078] In another embodiment, C6-C 12 fatty acids are present in the herbicidal composition in an amount in the range of from about 30 wt% to about 60 wt%, or from about 40 wt% to about 60 wt%, or from about 50 wt% to about 60 wt%, or from about 55 wt% to about 60 wt%.

[0079] When referred to as a working spray composition, the herbicidal composition generally comprises less than about 10 wt%, or less than about 5 wt%, or less than about 2 wt% of C6-C 12 fatty acids.

[0080] In one embodiment, the herbicide composition comprises less than about 10 wt%, or less than about 5 wt%, or less than about 2 wt% of C6-C 12 fatty acids.

[0081] In another embodiment, the C6-C12 fatty acids are present in the herbicide composition in an amount in the range of from about 1 wt% to about 10 wt%, or from about 1 wt% to about 5 wt%, or from about 1 wt% to about 3 wt%, or from about 1 wt% to about 2 wt%.

[0082] Unlike many conventional herbicide compositions (including those containing fatty acids), the active herbicide (i.e., fatty acid) used according to the present invention is provided in its acid form (i.e., not in the form of a salt) and thus has limited water solubility. Accordingly, the herbicide composition according to the present invention exists mainly in the form of an emulsion for the fatty acid component. This is in contrast to many conventional herbicide compositions that typically use highly water-soluble forms of the active herbicide (such as metal or ammonium salt forms).

[0083] In one embodiment, the herbicide composition does not include water-soluble metal or ammonium salts of the active herbicide.

[0084] In another embodiment, the herbicide composition is provided in the form of an emulsion, wherein the active herbicide is located in the oil phase of this emulsion.

[0085] The herbicide composition according to the present invention further comprises an alcohol alkoxylate.

[0086] The alcohol alkoxylate component in the composition helps to stabilize the emulsion form of the composition.

[0087] Alcohol alkoxylates are well-known nonionic surfactants obtained by alkoxylating fatty alcohols.

[0088] The "alcohol" component or residue of the alcohol alkoxylate will typically be C6-C 24 alcohol. The alcohol component can be straight-chain or branched-chain. In one embodiment, the alcohol component is straight-chain.

[0089] In one embodiment, the alcohol alkoxylate is a C6-C 24 alcohol alkoxylate.

[0090] To avoid any doubt, the "C6-C 24 " in the alcohol alkoxylate is intended to refer to the carbon atoms present in the alcohol residue. 24

[0091] The "alkoxylate" component of an alcohol alkoxylate refers to an oligomer or polymer constructed from alkylene oxide units. The alkoxylate component can be branched or linear. In one embodiment, the alkoxylate component is linear.

[0092] When describing an alcohol alkoxylate, it is sometimes convenient to refer to the number of alkylene oxide units that make up the alkoxylate component. The alkoxylate component typically comprises from about 4 to about 12 or from 9 to about 12 alkylene oxide units.

[0093] The alcohol alkoxylate can be represented by the general formula RO((CR X R Y ) i O) j H, where R is a C6-C 24 alkyl group, R X and R Y are each independently selected from hydrogen and alkyl groups, i is an integer in the range of 1 to 10, and j is an integer in the range of 4 to 12. Generally, R X and R Y are each independently selected from hydrogen and C 1～6 alkyl groups, and i is an integer selected from 2, 3, and 4. When i > 1, each (CR X R Y ) can be the same or different. For example, when the oxyalkylene unit is an oxyethylene unit, R X and R Y are both hydrogen and i = 2 (i.e., -O(CH2)2-), or when the oxyalkylene unit is an oxypropylene unit, i = 2 and for the first "i", R X and R Y are both hydrogen, and for the second "i", R X and R Y can be hydrogen and methyl, respectively (i.e., -OCH2CH(CH3)-).

[0094] The oxyalkylene units can be derived from alkylene oxides such as ethylene oxide, propylene oxide, or butylene oxide.

[0095] In one embodiment, the alcohol alkoxylate is an alcohol ethoxylate.

[0096] In another embodiment, the alcohol alkoxylate is a C6-C 24 alcohol ethoxylate.

[0097] The alcohol alkoxylate used according to the present invention can be a mixture of different alcohol alkoxylates.

[0098] In one embodiment, the alcohol alkoxylate is a mixture of different alcohol alkoxylates.

[0099] In yet another embodiment, the alcohol alkoxylate comprises a mixture of C9 - C 11 alcohol alkoxylate and C 16 -C 18 alcohol alkoxylate.

[0100] In yet another embodiment, the alcohol alkoxylate comprises a mixture of C9 - C 11 alcohol ethoxylate and C 18 alcohol ethoxylate.

[0101] Without wishing to be bound by theory, it is believed that formulating the herbicide composition according to the invention with a mixture of C9 - C 11 alcohol alkoxylate and C 16 -C 18 alcohol alkoxylate imparts excellent stability and application properties to the composition. This in turn is believed to provide improved application efficacy.

[0102] The alcohol alkoxylate is generally present in the herbicide composition in an amount in the range of from about 0.5 wt% to about 25 wt%.

[0103] When referred to as a concentrate, the herbicide composition generally comprises greater than about 10 wt%, or greater than about 15 wt%, or greater than about 20 wt% of the alcohol alkoxylate.

[0104] In one embodiment, the alcohol alkoxylate is present in the herbicide composition in an amount greater than about 10 wt%, or greater than about 15 wt% or greater than about 20 wt%.

[0105] In another embodiment, the alcohol alkoxylate is present in the herbicide composition in an amount in the range of from about 10 wt% to about 25 wt%, or from about 15 wt% to about 25 wt%, or from about 20 wt% to about 25 wt%.

[0106] When referred to as a working spray composition, the herbicide composition generally comprises less than about 10 wt%, or less than about 5 wt%, or less than about 2 wt%, or less than about 1 wt% of the alcohol alkoxylate.

[0107] In one embodiment, the herbicide composition comprises less than about 10 wt%, or less than about 5 wt%, or less than about 2 wt%, or less than about 1 wt% of the alcohol alkoxylate.

[0108] In another embodiment, the alcohol alkoxylate is present in the herbicide composition in an amount in the range of from about 0.5 wt% to about 10 wt%, or from about 0.5 wt% to about 5 wt%, or from about 0.5 wt% to about 3 wt%, or from about 0.5 wt% to about 2 wt%.

[0109] When the herbicidal compositions according to the invention comprise mixtures of different alcohol alkoxylates, they may be present in the same or different amounts.

[0110] In one embodiment, the herbicidal composition comprises C9-C 11 alcohol alkoxylate and C 16 -C 18 alcohol alkoxylate mixture in a weight ratio of about 1:2, respectively.

[0111] The herbicidal compositions according to the invention comprise a hydrophobic liquid.

[0112] The expression "hydrophobic liquid" is intended to mean (i) a substance that is liquid at the typical application temperature of the herbicidal composition, such as at least 5 °C, or 10 °C, or 15 °C, or 20 °C or 25 °C, and (ii) has little or no solubility in water.

[0113] Examples of suitable hydrophobic liquids include, but are not limited to, organic solvents (such as xylene, toluene, C5-C 12 alkanes), mineral oils (such as paraffin oil), vegetable oils (such as seed oils and terpenes), petroleum distillates (such as kerosene, mineral spirits, petroleum solvents and Stoddard solvent), animal oils, and combinations thereof.

[0114] Examples of suitable vegetable oils that can be used include, but are not limited to, methylated seed oils, alkylated seed oils.

[0115] In one embodiment, the hydrophobic liquid comprises one or more terpenes.

[0116] Examples of suitable terpenes that can be used include, but are not limited to, pinene, nerol, citral, menthol, limonene, carene, cineol, camphene, dipentene and terpinolene.

[0117] In one embodiment, the hydrophobic liquid comprises one or more terpenes selected from pinene, nerol, citral, menthol, limonene, carene, cineol, camphene, dipentene and terpinolene and combinations thereof.

[0118] In another embodiment, the hydrophobic liquid is selected from dipentene, pinene and limonene.

[0119] Those skilled in the art will understand that terpenes generally originate from extracts of vegetable oils such as gum turpentine, pine oil, eucalyptus oil, conifer oil, tea tree oil, and combinations thereof.

[0120] In one embodiment, the herbicidal composition comprises one or more of gum turpentine, pine oil, eucalyptus oil, conifer oil, tea tree oil, and combinations thereof.

[0121] In one embodiment, the herbicide composition comprises one or more terpenes derived from an extract of one or more of gum turpentine, pine oil, eucalyptus oil, coniferous tree oil, tea tree oil, and combinations thereof.

[0122] The hydrophobic liquid is generally present in the herbicide composition in an amount in the range of from about 0.1 wt% to about 30 wt%.

[0123] When referred to as a concentrate, the herbicide composition generally comprises greater than about 15 wt%, or greater than about 20 wt%, or greater than about 25 wt% of the hydrophobic liquid.

[0124] In one embodiment, the hydrophobic liquid is present in the herbicide composition in an amount greater than about 15 wt%, or greater than about 20 wt%, or greater than about 25 wt%.

[0125] In another embodiment, the hydrophobic liquid is present in the herbicide composition in an amount in the range of from about 15 wt% to about 30 wt%, or from 20 wt% to about 30 wt%, or from 25 wt% to about 30 wt%.

[0126] When referred to as a working spray composition, the herbicide composition generally comprises less than about 10 wt%, or less than about 5 wt%, or less than about 2 wt% of the hydrophobic liquid.

[0127] In one embodiment, the herbicide composition comprises less than about 10 wt%, or less than about 5 wt%, or less than about 2 wt% of the hydrophobic liquid.

[0128] In another embodiment, the hydrophobic liquid is present in the herbicide composition in an amount in the range of from about 0.1 wt% to about 10 wt%, or from about 0.1 wt% to about 5 wt%, or from about 0.5 wt% to about 3 wt%, or from about 0.5 wt% to about 2 wt%.

[0129] The herbicide composition further comprises a pH-sensitive hydrogel-forming polymer.

[0130] "pH-sensitive hydrogel-forming polymer" refers to a polymer that forms a hydrogel in response to a change in pH.

[0131] The herbicide composition according to the present invention has an acidic pH. At this acidic pH, the pH-sensitive hydrogel-forming polymer is not in the form of a hydrogel. In other words, the herbicide composition according to the present invention has an acidic pH that does not promote the formation of a hydrogel of the pH-sensitive hydrogel-forming polymer.

[0132] pH-sensitive hydrogel-forming polymers suitable for use in the present invention generally comprise a plurality of acid functional groups (such as carboxylic acids), which are present in their acidic or protonated form (i.e., in a non-hydrogel form) at a suitable acidic pH. When the pH increases towards a basic pH, the acid functional groups of the polymer ionize, which in turn promotes the formation of the hydrogel.

[0133] Thus, such pH-sensitive hydrogel-forming polymers used according to the present invention are generally pH-sensitive hydrogel-forming polymers that transform from a form that is not a hydrogel at acidic pH to a hydrogel form in response to an increase in pH.

[0134] The pH-sensitive hydrogel-forming polymer can transform into a hydrogel, for example, at a pH greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6, or greater than about 6.5, or greater than 7.

[0135] The pH-sensitive hydrogel-forming polymer can transform into a hydrogel, for example, at a pH within the range of about 4 to 8, or about 4.5 to 7, or about 5 to 7, or about 5.5 to 7.

[0136] In view of the fact that pH-sensitive hydrogel-forming polymers transform into hydrogels in response to an increase in pH, they can also be referred to as basic hydrogel-forming polymers.

[0137] Thus, basic hydrogel-forming polymers can be referred to as pH-sensitive hydrogel-forming polymers that transform into hydrogels in response to an increase in pH towards a basic pH.

[0138] The pH-sensitive hydrogel-forming polymers used according to the present invention do not exist in the herbicide composition in their hydrogel form.

[0139] The pH-sensitive hydrogel-forming polymers used according to the present invention are appropriately selected to exist in their non-hydrogel form at the acidic pH of the herbicide composition.

[0140] The pH-sensitive hydrogel-forming polymers used according to the present invention can be homopolymers or copolymers.

[0141] The pH-sensitive hydrogel-forming polymers used according to the present invention can include polymerization residues of acrylic acid.

[0142] The pH-sensitive hydrogel-forming polymer can have a certain degree of crosslinking.

[0143] In one embodiment, the pH-sensitive hydrogel-forming polymer comprises polymerization residues of acrylic acid and optionally one or more acrylic acid alkyl esters.

[0144] Suitable pH-sensitive hydrogel-forming polymers are commercially available. For example, those sold by Lubrizol under the name .

[0145] The pH-sensitive hydrogel-forming polymer is generally present in the herbicide composition in an amount in the range of from about 0.0002 wt% to about 0.01 wt%.

[0146] When referred to as a concentrate, the herbicide composition generally comprises a pH-sensitive hydrogel-forming polymer in an amount greater than about 0.001 wt%, or greater than about 0.005 wt%, or greater than about 0.008 wt%.

[0147] In one embodiment, the pH-sensitive hydrogel-forming polymer is present in the herbicide composition in an amount greater than about 0.001 wt%, or greater than about 0.005 wt%, or greater than about 0.008 wt%.

[0148] In another embodiment, the pH-sensitive hydrogel-forming polymer is present in the herbicide composition in an amount in the range of from about 0.001 wt% to about 0.01 wt%, or from 0.005 wt% to about 0.01 wt%, or from 0.008 wt% to about 0.01 wt%.

[0149] When referred to as a working spray composition, the herbicide composition generally comprises a pH-sensitive hydrogel-forming polymer in an amount less than about 0.001 wt%, or less than about 0.0006 wt%, or less than about 0.0004 wt%.

[0150] In one embodiment, the herbicide composition comprises a pH-sensitive hydrogel-forming polymer in an amount less than about 0.001 wt%, or less than about 0.0006 wt%, or less than about 0.0004 wt%.

[0151] In another embodiment, the pH-sensitive hydrogel-forming polymer is present in the herbicide composition in an amount in the range of from about 0.0002 wt% to about 0.001 wt%, or from 0.0002 wt% to about 0.0006 wt%, or from 0.0002 wt% to about 0.0004 wt%.

[0152] The herbicide composition further comprises fumed silica.

[0153] Fumed silica is generally made by flame pyrolysis of silicon halide compounds or from silica sand vaporized at high temperature. The resulting silica particles are very small (generally having a primary particle size in the range of about 5 to 50 nm) and have a high specific surface area (generally in the range of about 50 - 600 m 2 / g).

[0154] Fumed silica suitable for use according to the present invention is commercially available, for example, the kind sold under the name as such.

[0155] In one embodiment, the fumed silica has a primary particle size of about 5 nm to about 20 nm and a specific surface area of 100 m 2 / g to about 350 m 2 / g.

[0156] The fumed silica is generally present in the herbicide composition in an amount in the range of about 0.0003 wt% to about 0.01 wt%.

[0157] When called a concentrate, the herbicide composition generally includes more than about 0.001 wt%, or more than about 0.004 wt%, or more than about 0.006 wt% of fumed silica. In one embodiment, the fumed silica is present in the herbicide composition in an amount more than about 0.001 wt%, or more than about 0.004 wt%, or more than about 0.006 wt%.

[0158] In another embodiment, the fumed silica is present in the herbicide composition in an amount in the range of about 0.001 wt% to about 0.01 wt%, or 0.004 wt% to about 0.01 wt%, or 0.006 wt% to about 0.01 wt%.

[0159] When called a working spray composition, the herbicide composition generally includes less than about 0.001 wt%, or less than about 0.0008 wt%, or less than about 0.0006 wt% of fumed silica.

[0160] In one embodiment, the herbicide composition includes less than about 0.001 wt%, or less than about 0.0008 wt%, or less than about 0.0006 wt% of fumed silica.

[0161] In another embodiment, the fumed silica is present in the herbicide composition in an amount in the range of about 0.0003 wt% to about 0.001 wt%, or about 0.0003 wt% to about 0.0008 wt%, or about 0.0003 wt% to about 0.0006 wt%.

[0162] The fumed silica is generally present in the herbicide composition in a substantially uniformly distributed or dispersed form.

[0163] The herbicide composition may further include one or more other components to assist in the preparation and / or application of the composition.

[0164] For example, the herbicide composition may include a pH regulator such as an alkali metal hydroxide (e.g., sodium hydroxide).

[0165] In one embodiment, the herbicide composition includes: water in an amount in the range of about 0.1 wt% to about 10 wt%, or about 0.1 wt% to about 7 wt%, or about 0.1 wt% to about 5 wt%; C6-C 12 fatty acids in an amount in the range of about 30 wt% to about 60 wt%, or about 40 wt% to about 60 wt%, or about 50 wt% to about 60 wt%, or about 55 wt% to about 60 wt%; alcohol alkoxylates in an amount in the range of about 10 wt% to about 25 wt%, or about 15 wt% to about 25 wt%, or about 20 wt% to about 25 wt%; a hydrophobic liquid in an amount in the range of about 15 wt% to about 30 wt%, or 20 wt% to about 30 wt%, or 25 wt% to about 30 wt%; a pH-sensitive hydrogel-forming polymer in an amount in the range of about 0.001 wt% to about 0.01 wt%, or 0.005 wt% to about 0.01 wt%, or 0.008 wt% to about 0.01 wt%; and fumed silica in an amount in the range of about 0.001 wt% to about 0.01 wt%, or 0.004 wt% to about 0.01 wt%, or 0.006 wt% to about 0.01 wt%.

[0166] In another embodiment, the herbicide composition includes: water in an amount in the range of about 50 wt% to about 98 wt%, or about 70 wt% to about 98 wt%, or about 80 wt% to about 98 wt%, or about 85 wt% to about 95 wt%; C6-C 12 fatty acids in an amount in the range of about 1 wt% to about 10 wt%, or about 1 wt% to about 5 wt%, or about 1 wt% to about 3 wt%, or about 1 wt% to about 2 wt%; alcohol alkoxylates in an amount in the range of about 0.5 wt% to about 10 wt%, or about 0.5 wt% to about 5 wt%, or about 0.5 wt% to about 3 wt%, or about 0.5 wt% to about 2 wt%; a hydrophobic liquid in an amount in the range of about 0.1 wt% to about 10 wt%, or about 0.1 wt% to about 5 wt%, or about 0.5 wt% to about 3 wt%, or about 0.5 wt% to about 2 wt%; a pH-sensitive hydrogel-forming polymer in an amount in the range of about 0.0002 wt% to about 0.001 wt%, or about 0.0002 wt% to about 0.0006 wt%, or about 0.0002 wt% to about 0.0004 wt%; and fumed silica in an amount in the range of about 0.0003 wt% to about 0.001 wt%, or about 0.0003 wt% to about 0.0008 wt%, or about 0.0003 wt% to about 0.0006 wt%.

[0167] The present invention also provides a method for preparing a herbicide composition. The method includes providing an aqueous silica-containing composition, which includes water, fumed silica, and a pH-sensitive hydrogel-forming polymer.

[0168] The aqueous silica-containing composition generally includes about 90 wt% to about 99.5 wt% of water, about 0.25 wt% to about 2.5 wt% of fumed silica, and about 0.25 wt% to about 2.5 wt% of a pH-sensitive hydrogel-forming polymer.

[0169] In one embodiment, the aqueous silica-containing composition includes about 90 wt% to about 99.5 wt% of water, about 0.25 wt% to about 2.5 wt% of fumed silica, and about 0.25 wt% to about 2.5 wt% of a pH-sensitive hydrogel-forming polymer.

[0170] The aqueous silica-containing composition can be provided by mixing formulation components including water, fumed silica, and a pH-sensitive hydrogel-forming polymer in a container.

[0171] The aqueous silica-containing composition can further include one or more other formulation components, such as components for adjusting the pH.

[0172] In one embodiment, the pH of the aqueous silica-containing composition is increased towards an alkaline pH by adding an alkali metal hydroxide such as sodium hydroxide.

[0173] If used, the pH-adjusting reagent can be introduced in an amount in the range of about 0.001 wt% to about 0.05 wt%.

[0174] In one embodiment, the pH-adjusting reagent is used to increase the pH of the aqueous silica-containing composition.

[0175] The introduction of the pH-adjusting reagent into the aqueous silica-containing composition is generally to increase the pH of the composition, thereby triggering the transformation of the pH-sensitive hydrogel-forming polymer into a hydrogel. In other words, the pH-adjusting reagent is used to increase the pH of the aqueous silica-containing composition to a pH at which the pH-sensitive hydrogel-forming polymer forms a hydrogel.

[0176] The pH-adjusting reagent that increases the pH can be referred to as an alkaline pH-adjusting reagent.

[0177] In one embodiment, the alkaline pH-adjusting reagent is introduced into the aqueous silica-containing composition to increase its pH to greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6, or greater than about 6.5, or greater than 7.

[0178] In another embodiment, an alkaline pH adjusting reagent is introduced into the aqueous silica-containing composition to increase its pH to within a range of about 4 to 8, or within a range of about 4.5 to 7, or within a range of about 5 to 7, or within a range of about 5.5 to 7.

[0179] In yet another embodiment, the aqueous silica-containing composition has a pH that promotes the formation of a pH-sensitive hydrogel-forming polymer into a hydrogel.

[0180] In one embodiment, the aqueous silica-containing composition has a pH greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6, or greater than about 6.5, or greater than 7 to promote the formation of a pH-sensitive hydrogel-forming polymer into a hydrogel.

[0181] In another embodiment, the aqueous silica-containing composition has a pH within a range of about 4 to 8, or within a range of about 4.5 to 7, or within a range of about 5 to 7, or within a range of about 5.5 to 7 to promote the formation of a pH-sensitive hydrogel-forming polymer into a hydrogel.

[0182] In one embodiment, the aqueous silica-containing composition has an alkaline pH.

[0183] The pH-sensitive hydrogel-forming polymer forms a hydrogel by promoting an increase in the pH of the aqueous silica-containing composition, and the composition thickens due to the presence of the hydrogel. It has been found that increasing the viscosity of the aqueous silica-containing composition helps to maintain a substantially uniform distribution of the fumed silica particles throughout the composition. In other words, it has been found that the formation of the hydrogel helps to minimize or prevent the undesirable aggregation of the fumed silica particles within the aqueous silica-containing composition. The resulting aqueous silica-containing composition in this thickened state can then be combined with other herbicide composition components in a manner that promotes excellent dispersion / distribution of the fumed silica particles within the herbicide composition so formed.

[0184] It should be understood that combining this thickened form of the aqueous silica-containing composition with other herbicide composition components will still provide a final herbicide composition having an acidic pH that does not promote the formation of a pH-sensitive hydrogel-forming polymer into a hydrogel. In other words, one or more of these other components of the herbicide composition will provide sufficient acidity to convert the hydrogel form of the pH-sensitive hydrogel-forming polymer derived from the aqueous silica-containing composition back to its non-hydrogel form.

[0185] A method of preparing a herbicide composition includes combining the aqueous silica-containing composition so formed with an alcohol alkoxide to form a liquid alcohol alkoxide-containing composition.

[0186] A composition that forms a "liquid" alcohol alkoxide means that at least the alcohol alkoxide component of the composition is in liquid form. Since some alcohol alkoxides applicable to the present invention can exist in solid form at room temperature, the step of combining the aqueous silica-containing composition with the alcohol alkoxide will require heating to promote the formation of the liquid state of the alcohol alkoxide used.

[0187] In one embodiment, the combination of the aqueous silica-containing composition and the alcohol alkoxide is carried out by heating.

[0188] Depending on the type of alcohol alkoxide used, the alcohol alkoxide can be combined with the aqueous silica-containing composition in one or multiple steps. For example, in the case of using a mixture of different alcohol alkoxides, one type of alcohol alkoxide can be combined with the aqueous silica-containing composition, and then a different alcohol alkoxide can be added separately.

[0189] Regardless of the manner in which the alcohol alkoxide is combined with the aqueous silica-containing composition, it will be important that the added alcohol alkoxide is in liquid form before proceeding to the next step.

[0190] Then, the method for preparing the herbicide composition includes the step of combining the thus-formed composition containing the liquid alcohol alkoxide with C6 - C 12 fatty acid and a hydrophobic liquid.

[0191] The fatty acid and the hydrophobic liquid components can be combined with the composition containing the liquid alcohol alkoxide separately, sequentially, or as a mixture.

[0192] During the process of adding one or more components according to the method of the present invention, the composition can be agitated (such as stirred) and / or heated to promote the mixing and / or dispersion of these components.

[0193] As described above, the thus-formed herbicide composition has an acidic pH. This acidic pH can be inherently generated after combining all the ingredients used. Alternatively, the pH of the composition can be adjusted at any time during its preparation to ensure that the final composition has an acidic pH.

[0194] For example, the fatty acid component and / or the pH-sensitive hydrogel-forming polymer can provide the acidic pH of the composition.

[0195] Alternatively, one or more additional components that provide or help provide the acidic pH of the composition can be included or introduced into the composition. Such additional components can include, but are not limited to, hydrochloric acid and acetic acid.

[0196] The constituent components of the herbicide composition can be combined in any suitable amounts according to the method of the present invention to provide the concentrations of the components described herein.

[0197] Generally, the method of preparing the herbicide composition involves combining a certain amount of the constituent components to provide a concentrate, which can then be diluted with water to provide the working composition required for the intended application.

[0198] In one embodiment, the concentrate thus formed is then diluted with a combination of water and acetic acid in order to provide the working composition required for the intended application (i.e., it is ready-to-use).

[0199] In one embodiment, the method of preparing the herbicide composition comprises combining an amount of an aqueous silica-containing composition of from about 1 wt% to about 5 wt%, an amount of an alcohol alkoxylate of from about 15 wt% to about 25 wt%, an amount of C6 - C 12 fatty acids and an amount of a hydrophobic liquid of from about 20 wt% to about 40 wt%.

[0200] In another embodiment, the method of preparing the herbicide composition comprises combining an amount of an aqueous silica-containing composition of from about 1 wt% to about 5 wt%, an amount of an alcohol alkoxylate of from about 15 wt% to about 25 wt%, an amount of C6 - C 12 fatty acids, an amount of a hydrophobic liquid of from about 20 wt% to about 40 wt% and an amount of acetic acid in the range of from about 0.01 wt% to about 1 wt%.

[0201] The present invention further provides a herbicide composition produced according to the method described herein.

[0202] The present invention also provides a method of killing plants or retarding their growth, which method comprises contacting the plants with a herbicide composition according to the present invention.

[0203] The present invention further provides for controlling plant growth at a location, which method comprises applying a herbicide composition according to the present invention to the location.

[0204] As used herein, the expression "controlling plant growth at a location" is intended to mean retarding, inhibiting or preventing plant growth at that location. The term "location" is intended to mean any position where plant growth may occur. For example, the location may be an area of soil in which plants can grow or a surface on which plants can grow.

[0205] Contacting a plant with a herbicidal composition according to the invention or applying a herbicidal composition according to the invention to a locus can be achieved by conventional methods of applying herbicidal compositions. For example, the herbicidal composition can be applied directly by painting or pouring it onto the plant or locus. Alternatively, the herbicidal composition can be sprayed onto the plant or locus.

[0206] The invention also provides for the use of a herbicidal composition according to the invention for killing plants or retarding their growth. The invention further provides for the use of a herbicidal composition according to the invention for controlling the growth of plants at a locus.

[0207] The use of a herbicidal composition according to the invention can be carried out as described herein and as known to those skilled in the art.

[0208] As used herein, the term "alkyl", used alone or in a compound word, denotes straight-chain, branched-chain or cyclic alkyl, preferably C 1～20 alkyl, such as C 1～10 or C 1～6Examples of straight-chain and branched-chain alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, 1,2-dimethylpropyl, 1,1-dimethylpropyl, hexyl, 4-methylpentyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 1,2,2-trimethylpropyl, 1,1,2-trimethylpropyl, heptyl, 5-methylhexyl, 1-methylhexyl, 2,2-dimethylpentyl, 3,3-dimethylpentyl, 4,4-dimethylpentyl, 1,2-dimethylpentyl, 1,3-dimethylpentyl, 1,4-dimethylpentyl, 1,2,3-trimethylbutyl, 1,1,2-trimethylbutyl, 1,1,3-trimethylbutyl, octyl, 6-methylheptyl, 1-methylheptyl, 1,1,3,3-tetramethylbutyl, nonyl, 1-, 2-, 3-, 4-, 5-, 6- or 7-methyloctyl, 1-, 2-, 3-, 4- or 5-ethylheptyl, 1-, 2- or 3-propylhexyl, decyl, 1-, 2-, 3-, 4-, 5-, 6-, 7- and 8-methylnonyl, 1-, 2-, 3-, 4-, 5- or 6-ethyloctyl, 1-, 2-, 3- or 4-propylheptyl, undecyl, 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8- or 9-methyldecyl, 1-, 2-, 3-, 4-, 5-, 6- or 7-ethylnonyl, 1-, 2-, 3-, 4- or 5-propyl octyl, 1-, 2- or 3-butylheptyl, 1-pentylhexyl, dodecyl, 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9- or 10-methylundecyl, 1-, 2-, 3-, 4-, 5-, 6-, 7- or 8-ethyldecyl, 1-, 2-, 3-, 4-, 5- or 6-propylnonyl, 1-, 2-, 3- or 4-butyl octyl, 1-, 2-pentylheptyl, and the like. Examples of cyclic alkyl groups include monocyclic or polycyclic alkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, and the like. When an alkyl group is generally referred to as "propyl", "butyl", etc., it should be understood that, where appropriate, this can refer to any of the straight-chain, branched-chain, and cyclic isomers.

[0209] The present invention will be described below with reference to non-limiting examples.

[0210] Examples

[0211] Comparative Example 1: Composition 1

[0212] Based on the formulation shown in Table 1, a dispersion of fumed silica, water, and ethoxylated alcohol was prepared. Pelargonic acid and pine oil were added. The solution was stirred for 15 minutes and filtered through a nylon filter. The resulting solution was sealed and stored in an airtight container.

[0213] Table 1: Composition 1

[0214] % by weight Ethoxylated C9 - 11 alcohol 13.9 Fumed silica 0.1 Water 0.1 Pelargonic acid* 55.9 Pine oil 30.0

[0215] * Nonanoic acid content: 515.6 g / L

[0216] Comparative Example 2: Composition 2

[0217] Based on the formulation shown in Table 2, prepare a dispersion of fumed silica in ethoxylated alcohol. Add nonanoic acid and pine oil. Stir the solution for 15 minutes and filter it through a nylon filter. Seal the resulting solution and store it in an airtight container.

[0218] Table 2: Composition 2

[0219]

[0220]

[0221] * Nonanoic acid content: 443.0 g / L

[0222] Comparative Example 3: Composition 3

[0223] Based on the formulation shown in Table 3, prepare a dispersion of fumed silica, water and ethoxylated alcohol. Add nonanoic acid and dipentene. Stir the solution for 15 minutes and filter it through a nylon filter. Seal the resulting solution and store it in an airtight container.

[0224] Table 3: Composition 3

[0225] % by weight Ethoxylated C12 - 14 alcohol 16.9 Fumed silica 0.1 Water 0.2 Pelargonic acid* 47.8 Dipentene 35.0

[0226] * Nonanoic acid content: 424.8 g / L

[0227] Comparative Example 4: Composition 4

[0228] Based on the formulation shown in Table 4, prepare a dispersion of fumed silica, water and ethoxylated C9-11 alcohol. Heat the ethoxylated C18 alcohol to 40 °C, melt it and add it to the dispersion with stirring. Heat the product to 40 °C and agitate. Add nonanoic acid and dipentene. Stir the composition for 15 minutes, cool it to room temperature, and filter it through a nylon filter. Seal the resulting product and store it in an airtight container.

[0229] Table 4: Composition 4

[0230] % by weight Ethoxylated C9 - 11 alcohol 6.0 Fumed silica 0.1 Water 0.2 Ethoxylated C18 alcohol 11.7 Pelargonic acid* 50.0 Dipentene 32.0

[0231] * Nonanoic acid content: 445.9 g / L

[0232] Comparative Example 5: Composition 5

[0233] Based on the formulation shown in Table 5, prepare a dispersion of carbomer acrylic polymer in water-ethoxylated C9-11 alcohol. Heat the ethoxylated C18 alcohol to 40 °C, melt it and add it to the dispersion with stirring. Heat the product to 40 °C and agitate. Add pelargonic acid and dipentene. Stir the composition for 15 minutes, cool to room temperature, and filter through a nylon filter. Seal the resulting product and store it in an airtight container.

[0234] Table 5: Composition 5

[0235] % by weight Ethoxylated C9 - 11 alcohol 6.0 Carbomer acrylic polymer 0.1 Water 0.2 Ethoxylated C18 alcohol 11.7 Pelargonic acid* 50.0 Dipentene 32.0

[0236] * Pelargonic acid content: 445.9 g / L

[0237] Example 1: Composition 6

[0238] Based on the formulation shown in Table 6, prepare a silica colloid composition by adding fumed silica and carbomer acrylic polymer to water with stirring. Add sodium hydroxide solution to increase the pH of the liquid to 5.5 and thicken the liquid by forming a hydrogel polymer, which helps to keep the silica in a good dispersed state.

[0239] Produce the composition of Table 7 by adding the silica colloid composition (Table 6) to ethoxylated C9-11 alcohol. Heat the ethoxylated C18 alcohol to 40 °C, melt it and add it to the dispersion with stirring. Heat the product to 40 °C and agitate. Add pelargonic acid and gum turpentine. Stir the composition for 15 minutes, cool to room temperature, and filter through a nylon filter. The resulting product has an acidic pH and is sealed and stored in an airtight container.

[0240] Table 6: Silica colloid composition

[0241]

[0242]

[0243] Table 7: Composition 6

[0244] % by weight Ethoxylated C9 - 11 alcohol 6.5 Colloidal silica composition 2.0 Ethoxylated C18 alcohol 12.5 Pelargonic acid* 50.0 Pure gum turpentine 29.0

[0245] * Pelargonic acid content: 455.7 g / L

[0246] Example 2: Composition 7

[0247] Based on the formulation shown in Table 8, a silica colloidal composition is prepared by adding fumed silica and carbomer acrylic polymer to water under stirring. Sodium hydroxide solution is added to increase the pH of the liquid to 5.5, and the liquid is thickened by forming a hydrogel polymer, which helps to keep the silica in a good dispersed state.

[0248] The composition of Table 9 is produced by adding the silica colloidal composition (Table 8) to ethoxylated C12-14 alcohol. The ethoxylated C18 alcohol is heated to 40 °C, melted and added to the dispersion under stirring. The product is heated to 40 °C and agitated. Nonanoic acid and gum turpentine are added. The composition is stirred for 15 minutes, cooled to room temperature and filtered through a nylon filter. The resulting product has an acidic pH and is sealed and stored in an airtight container.

[0249] Table 8: Silica Colloidal Composition

[0250]

[0251]

[0252] Table 9: Composition 7

[0253] % by weight Ethoxylated C12 - 14 alcohol 6.4 Colloidal silica composition 2.2 Ethoxylated C18 alcohol 12.8 Pelargonic acid* 49.4 Pure gum turpentine 29.2

[0254] * Content of nonanoic acid: 450.4 g / L

[0255] Example 3: Composition 8

[0256] Based on the formulation shown in Table 10, a silica colloidal composition is prepared by adding fumed silica and carbomer acrylic polymer to water under stirring. Sodium hydroxide solution is added to increase the pH of the liquid to 5.5, and the liquid is thickened by forming a hydrogel polymer, which helps to keep the silica in a good dispersed state.

[0257] The composition of Table 11 is produced by adding the silica colloidal composition (Table 10) to ethoxylated C9-11 alcohol. The ethoxylated C18 alcohol is heated to 40 °C, melted and added to the dispersion under stirring. The product is heated to 40 °C and agitated. Nonanoic acid and dipentene are added. The composition is stirred for 15 minutes, cooled to room temperature and filtered through a nylon filter. The resulting product has an acidic pH and is sealed and stored in an airtight container.

[0258] Table 10: Silica Colloidal Composition

[0259]

[0260] Table 11: Composition 8.

[0261] % by weight Ethoxylated C9 - 11 alcohol 7.2 Colloidal silica composition 2.2 Ethoxylated C18 alcohol 14.3 Pelargonic acid* 49.9 Dipentene 26.4

[0262] *Nonanoic acid content: 444.1 g / L

[0263] Example 4: Composition 9

[0264] Based on the formulation shown in Table 12, a working spray mixture with a low pH, Composition 9, was prepared. Acetic acid was used to lower the pH of the emulsion. The resulting product had an acidic pH and was sealed and stored in an airtight container.

[0265] Table 12: Composition 9

[0266] % by weight Acetic acid (54%)* 11.2 Composition 8** 4.0 Water 84.8

[0267] *Acetic acid content: 60.0 g / L

[0268] **Nonanoic acid content: 20.3 g / L

[0269] Example 5: Field application of Compositions 1 - 9

[0270] Example 5a: Field trial to evaluate the weed control efficacy of Composition 1 in fallow land

[0271] A field trial was conducted in Victoria to evaluate the weed control efficacy of Composition 1 (515.6 g / L nonanoic acid) in fallow land. The treatment applied was 7 L of Composition 1 per 100 L of water at a spray application rate of 1000 L / ha and a diluted spray to the point of run-off. This was compared with Slasher Weed Killer (525 g / L nonanoic acid, 7 L per 100 L of water) at a spray application rate of 1000 L / ha or to the point of run-off and an untreated control.

[0272] Broadleaf weed species included Plantago Major [PLANTA], marshmallow (Malva parviflora) [MALPO], and Sonchus oleraceus [SONOL]. Grass weed species included only Poa Annua [POAAN].

[0273] At the BBCH 13 - 15 growth stage, a single foliar application was made to the weeds. Weed density was assessed at 0 days after application (0 DAA) before the treatment was applied and at 27 DAA. Weed brownout was assessed at 7 DAA, 17 DAA, and 27 DAA.

[0274] In fallow fields, compared with untreated controls, Composition 1 applied at a spray rate of 1000 L / ha or as a dilution spray to reach the runoff point at 7 L / 100 L provided significant wilting of PLANTA and MALPA, as well as significant wilting and density reduction of SONOL and POAAN, where the highest rates and dilution sprays applied to reach runoff were generally superior to lower rates.

[0275] When compared with the Slasher herbicide, the control efficacy of Composition 1 against PLANTA, MALPA, SONOL, and POAAN was reduced by 5 - 10%.

[0276] Example 5b: Field trial to evaluate the weed control efficacy of Compositions 2, 3, and 4 in fallow fields

[0277] A field trial was conducted in Victoria to evaluate the control of Cirsium vulgare, Packera Glabella, Lolium rigidum, and Oxalis Pes-caprae in fallow fields by Compositions 2 (nonanoic acid content: 443.0 g / L), Composition 3 (nonanoic acid content: 424.8 g / L), and Composition 4 (nonanoic acid content: 445.9 g / L). Compositions 2 - 4 were each applied as a spray mixture at 1000 L / and at a spray rate to reach the runoff point at 7 L per 100 L of water through a boomspray with flat fan nozzles. Compositions 2 - 4 were compared with the Slasher herbicide (525 g / L nonanoic acid, at 7 L per 100 L) applied at a total spray rate of 1000 L / ha through a boomspray and an untreated control. All herbicide treatments were applied to actively growing weeds in a coarse spray quality. At the time of application, Cirsium vulgare, Packera Glabella, and Oxalis Pes-caprae were at the 5 - 6 leaf stage, and Lolium rigidum was at the 3 - 4 leaf stage.

[0278] Pre-spray weed counts were taken at 0 days after application (0 DAA), and the number of surviving weeds was evaluated at 27 DAA. Weed wilting was evaluated at 7, 14, and 27 DAA.

[0279] At the same application rate, the efficacy of Composition 2 (nonanoic acid content: 443.0 g / L) and Composition 3 (nonanoic acid content: 424.8 g / L) was lower (2 - 5%) than that of the Slasher herbicide. When applied at more than 1000 L / ha, Compositions 2 and 3 achieved control of broadleaf weeds, with 92% and 96% control of Cirsium vulgare, 82% and 85% control of Senecio vulgaris, and 92% and 90% control of Oxalis pes-caprae compared to the untreated control. Despite good wilting at 14 DAA, Compositions 2 and 3 were not very effective in controlling Lolium rigidum, with 40% and 45% control recorded at 27 DAA compared to the untreated control.

[0280] When applied at 1000 L / ha, Composition 4 (nonanoic acid content: 445.9 g / L) was effective in controlling broadleaf weeds, completely controlling Cirsium vulgare, with 93% control of Senecio vulgaris, and 95% control of Oxalis pes-caprae compared to the untreated control. Despite excellent wilting at 14 DAA, Composition 4 was not very effective in controlling Lolium rigidum, with 60% control recorded at 27 DAA compared to the untreated control.

[0281] Composition 4 showed a strong proportional response for weed wilting. When applied at more than 1000 L / ha, the control of Lolium rigidum by Composition 4 was slightly lower than the equivalent control of broadleaf weeds compared to the Slasher herbicide.

[0282] Example 5c: Field trial to evaluate the efficacy of Composition 5 in controlling weeds in fallow land

[0283] A field trial was conducted in Victoria to evaluate the efficacy of Composition 5 (nonanoic acid content: 445.9 g / L) in controlling weeds in fallow land. Treatments included 7 L of Composition 5 per 100 L of water at a spray application rate of 1000 L / ha. This treatment was compared to 7 L of the Slasher herbicide (525 g / L of nonanoic acid) per 100 L of water at a spray application rate of 1000 L / ha and an untreated control.

[0284] Broadleaf weed species included Lactuca serriola, Sisymbrium officinale, and Sonchus oleraceus [SONOL]. The grass weed species included only Stenotaphrum secundatum.

[0285] At the BBCH 10 - 12 growth stage, a single foliar application was made to the weeds. Weed density was evaluated at 0 days after application (0 DAA) before treatment application and at 27 DAA. Weed withering was evaluated at 7 DAA, 17 DAA, and 27 DAA.

[0286] Compared to the untreated control, the application of Composition 5 (nonanoic acid content: 445.9 g / L) at a spray volume of 1000 L / ha provided early withering and reduced density of Sisymbrium officinale (87%) and Sonchus oleraceus (85%), as well as limited withering and reduced density of Lactuca serriola (75%) and Panicum repens (77%).

[0287] Composition 5 was generally less effective than the Slasher herbicide in controlling Sisymbrium officinale, Sonchus oleraceus, Lactuca serriola, and Panicum repens. The Slasher achieved 93 - 96% withering and density reduction.

[0288] Example 5d: Field trial to evaluate the weed control efficacy of Compositions 6, 7, and 8 in fallow land

[0289] A field trial was conducted in Victoria to evaluate and compare the control of Malva neglecta, Sonchus asper, Arctotheca calendula, and Poa annua in fallow land by Composition 6 (nonanoic acid content: 455.7 g / L), Composition 7 (nonanoic acid content: 455.7 g / L), and Composition 8 (nonanoic acid content: 444.1 g / L). Treatments included the application of Compositions 6 - 8 at 5 L per 100 L of water at a spray volume of 1000 L / ha each. At the BBCH 10 - 14 growth stage, a foliar spray treatment was applied to the actively growing weeds at a spray volume of 1000 L / ha using a hollow cone nozzle.

[0290] The treatment was compared with the Slasher herbicide (525 g / L nonanoic acid) at 7 L per 100 L of water at a spray application rate of 1000 L / ha and an untreated control.

[0291] Weed withering was evaluated at 7 days after application (7 DAA), 14 DAA, and 28 DAA, and weed density was also evaluated at 28 DAA.

[0292] For the control of Malva rotundifolia, Sonchus asper, Arctotheca populifolia, and annual bluegrass, Compositions 6 (nonanoic acid content: 455.7 g / L) and 7 (nonanoic acid content: 455.7 g / L) at 5 L per 100 L of water were at least as effective as 7 L per 100 L of water of Slasher herbicide (nonanoic acid content: 525 g / L), achieving a reduced level of regrowth. Composition 8 (nonanoic acid content: 444.1 g / L) at 5 L per 100 L of water was significantly more effective than 7 L per 100 L of water of Slasher herbicide (nonanoic acid content: 525 g / L), achieving a reduced level of regrowth.

[0293] At 1000 L / ha, Composition 8 at 5 L per 100 L of water provided significant control of Malva rotundifolia, Sonchus asper, Arctotheca populifolia, and annual bluegrass. By 28 DAA, Composition 8 achieved 93% wilt of Malva rotundifolia, 100% wilt of Sonchus asper and Arctotheca populifolia, and 96% wilt of annual bluegrass.

[0294] Slasher herbicide at 7 L per 100 L of water provided good control of Malva rotundifolia, Sonchus asper, Arctotheca populifolia, and annual bluegrass. By 28 DAA, the Slasher herbicide achieved 90% wilt of Malva rotundifolia, 90% wilt of Sonchus asper and Arctotheca populifolia, and 88% wilt of annual bluegrass.

[0295] Compared to the Slasher herbicide, Compositions 6 - 8 were used at a lower dose rate but still provided the same or better results.

[0296] Example 5e: Field trial to evaluate the weed control efficacy of herbicide Composition 8 in fallow land

[0297] A field trial was conducted in South Australia to evaluate the control of Bromus sp., Brassica tournefortii, Arctotheca calendula, and Diplotaxis tenuifolia by Composition 8 (nonanoic acid content: 444.1 g / L). Treatments included Composition 8 applied at 50 mL / L of water at spraying volumes of approximately 750 and 1000 L / ha. Treatments using Composition 8 were compared to Slasher herbicide (nonanoic acid content: 525 g / L) applied at 70 mL / L at a spraying volume of approximately 1000 L / ha and an untreated control (UTC). A foliar spray treatment was applied to actively growing weeds using an extended range flat fan nozzle (Lechler LU 120 - 08 nozzle).

[0298] Weed density was evaluated at 0 days after application (0 DAA) before treatment application and at 27 DAA. Weed withering was evaluated at 7 DAA, 17 DAA, and 27 DAA.

[0299] Compared to the UTC, the composition 8 applied at 50 ml / L water provided significant control of all weeds at all evaluation times. By 28 DAA, composition 8 achieved greater than 90% withering of all weeds at 750 and 1000 L / ha.

[0300] The Slasher herbicide applied at 70 mL / L provided comparable weed control with greater than 90% withering of weeds at 1000 L / ha application.

[0301] This field trial demonstrated the high performance of composition 8 as an herbicide for effectively controlling weeds in fallow fields. Compared to the Slasher herbicide, composition 8 achieved its performance with a lower concentration of the active ingredient nonanoic acid (444.1 g / L for composition 8 versus 525 g / L for the Slasher herbicide), a higher dilution level (50 g / L for composition 8 versus 70 g / L for the Slasher herbicide), and a lower application rate (750 L / ha for composition 8 versus 1000 L / ha for the Slasher herbicide). Composition 8 achieved effective weed control at a rate of 16.65 kg nonanoic acid / ha compared to 36.75 nonanoic acid / ha for the Slasher herbicide.

[0302] Example 5f: Field trial to evaluate the control efficacy of herbicide composition 9 on weeds in fallow fields

[0303] A field trial was conducted in New South Wales to evaluate and compare the control of black grass (Eragrostis setifolia) and volunteer canola (Brassica napus) in fallow fields by composition 8 (nonanoic acid content: 444.1 g / L) applied at 50 ml / L water (nonanoic acid content in the spray mixture: 21.1 g / L) and the composition 9 spray mixture (acetic acid content: 60.0 g / L, nonanoic acid content: 20.3 g / L). This treatment was compared to the Slasher herbicide (525 g / L nonanoic acid) applied at 70 ml / L water (nonanoic acid content in the spray mixture: 34.3 g / L) and an untreated control (UTC).

[0304] At the BBCH 10 - 14 growth stage, a foliar spray treatment was applied to actively growing weeds at the spray volume to runoff point using a hollow cone nozzle to simulate application in a home garden or domestic amenity area.

[0305] Weed withering (visual %) was evaluated at 7 DAA (days after application), and weed density (plants / m2) was evaluated at 0 DAA and 15 DAA, compared with the untreated control.

[0306] Compared with the UTC, at all evaluation times, Composition 8 (nonanoic acid content: 444.1 g / L) applied at 50 ml / L water (nonanoic acid content in the spray mixture: 21.1 g / L) provided significant control of all weeds. Blackgrass withering (% leaf area) was 94% after 3 DAA and 94% after 7 DAA. At 15 DAA, the blackgrass count (number / m2) was 6.5, while for the UTC it was 20. Volunteer rape withering (% leaf area) was 99% after 3 DAA and 99% after 7 DAA. At 15 DAA, the volunteer rape count (number / m2) was 0.4, while for the UTC it was 7.5.

[0307] Compared with the UTC, at all evaluation times, Composition 9 spray mixture (acetic acid content: 60.0 g / L, nonanoic acid content: 20.3 g / L) provided better control of all weeds. Blackgrass withering (% leaf area) was 100% after 3 DAA and 99% after 7 DAA. At 15 DAA, the blackgrass count (number / m2) was 2.5, while for the UTC it was 20. Volunteer rape withering (% leaf area) was 100% after 3 DAA and 100% after 7 DAA. At 15 DAA, the volunteer rape count (number / m2) was 0, while for the UTC it was 7.5.

[0308] Compared with the UTC, at all evaluation times, Slasher herbicide applied at 70 ml / L water (nonanoic acid content of 525 g / L) provided moderate control of all weeds. Blackgrass withering (% leaf area) was 93% after 3 DAA and 76% after 7 DAA. At 15 DAA, the blackgrass count (number / m2) was 12.8, while for the UTC it was 20. Volunteer rape withering (% leaf area) was 98% after 3 DAA and 93% after 7 DAA. At 15 DAA, the volunteer rape count (number / m2) was 0.3, while for the UTC it was 7.5.

[0309] Comparing two spraying mixtures containing only nonanoic acid, Composition 8 applied at 50 ml / L water (nonanoic acid content in the spraying mixture: 21.1 g / L) (nonanoic acid content: 444.1 g / L) provided numerically higher weed control than Slasher herbicide applied at 70 ml / L water (nonanoic acid content in the spraying mixture: 34.3 g / L) (525 g / L of nonanoic acid), even though the nonanoic acid active ingredient content of Composition 8 at 21.1 g / L was lower than that of Slaser at 34.3 g / L. For the more difficult-to-eradicate blackgrass, the difference in performance was particularly evident. After 15 DAA, the blackgrass count (number / m2) was 6.5 for Composition 8, 12.8 for Slasher herbicide, and 20 for UTC.

[0310] Compared with the high-performance Composition 8 applied at 50 ml / L water (nonanoic acid content in the spraying mixture: 21.1 g / L) (nonanoic acid content: 444.1 g / L) and Slasher herbicide applied at 70 ml / L water (nonanoic acid content in the spraying mixture: 34.3 g / L) (525 g / L of nonanoic acid), the spraying mixture of Composition 9 (acetic acid content: 60.0 g / L, nonanoic acid content: 20.3 g / L) provided better control of all weeds. For the more difficult-to-eradicate blackgrass, the difference was particularly evident. After 15 DAA, the blackgrass count (number / m2) was 2.5 for Composition 9, 6.5 for Composition 8, 12.8 for Slasher herbicide, and 20 for UTC.

[0311] Any reference in this specification to any prior publication (or information derived therefrom) or to any matter known is not and should not be taken as an admission or acknowledgment or any form of implication that the prior publication (or information derived therefrom) or the matter known forms part of the common general knowledge in the field of endeavour to which this specification pertains.

[0312] Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise" and variations such as "comprises" and "comprising" shall be understood to imply the inclusion of the stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

Claims

1. A herbicide composition having an acidic pH, said composition comprising water, at least 30 wt% of C6-C 12 fatty acid, alcohol alkoxylate, hydrophobic liquid, pH-sensitive hydrogel-forming polymer, and fumed silica, wherein, The pH of the composition does not promote the formation of a hydrogel of the pH-sensitive hydrogel-forming polymer.

2. The herbicide composition according to claim 1, wherein Water is present in an amount in the range of 0.1 wt% to 10 wt%.

3. The herbicide composition according to claim 1, wherein Water is present in an amount in the range of 0.1 wt% to 10 wt%, C6-C 12 Fatty acids are present in an amount in the range of 30 wt% to 60 wt%, alcohol alkoxylates are present in an amount in the range of 10 wt% to 25 wt%, hydrophobic liquids are present in an amount in the range of 15 wt% to 30 wt%, pH-sensitive hydrogel-forming polymers are present in an amount in the range of 0.001 wt% to 0.01 wt%, and fumed silica is present in an amount in the range of 0.001 wt% to 0.01 wt%.

4. The herbicide composition according to any one of claims 1 to 3, wherein The alcohol alkoxylate is C6 - C 24 alcohol alkoxylate.

5. The herbicide composition according to any one of claims 1 to 3, wherein, The alcohol alkoxylate includes C9 - C 11 alcohol alkoxylate and C 16 - C 18 mixture of alcohol alkoxylates.

6. The herbicide composition according to any one of claims 1 to 3, wherein the C6-C 12 fatty acids are selected from caproic acid, enanthic acid, octanoic acid, pelargonic acid, capric acid, undecanoic acid, lauric acid and sebacic acid.

7. The herbicide composition according to any one of claims 1 to 3, wherein The C6-C 12 fatty acids include pelargonic acid.

8. The herbicidal composition according to any one of claims 1 to 3, wherein the hydrophobic liquid comprises one or more terpenes selected from pinene, nerol, citral, menthol, limonene, carene, cineole, camphene, dipentene and terpinolene and combinations thereof.

9. The herbicidal composition according to any one of claims 1 to 3, further comprising acetic acid.

10. A method of killing plants or retarding plant growth, the method comprising contacting the plants with the herbicidal composition according to any one of claims 1 to 3.

11. A method of preparing a herbicidal composition, the method comprising: providing an aqueous silica-containing composition comprising water, fumed silica and a pH-sensitive hydrogel-forming polymer; combining the aqueous silica-containing composition with an alcohol alkoxide to form a liquid alcohol alkoxide-containing composition; and Combine the composition of the liquid alcohol alkoxide with C6-C 12 fatty acids and hydrophobic liquids to produce the herbicide composition; Among them, the herbicide composition thus formed has an acidic pH that does not promote the formation of polymers of the pH-sensitive hydrogel and includes at least 30 wt% of C6-C 12 fatty acids.

12. The method according to claim 11, wherein, the aqueous silica-containing composition has a pH that promotes the formation of a hydrogel of the pH-sensitive hydrogel-forming polymer.

13. The method according to claim 11 or 12, wherein, The C6-C 12 fatty acids include pelargonic acid.

14. The method according to claim 11 or 12, wherein combining the resulting herbicidal composition with water and acetic acid to provide a ready-to-use herbicidal composition having an acidic pH that does not promote the formation of a hydrogel of the pH-sensitive hydrogel-forming polymer.

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