Composition

Abstract

1. A liquid tank mix composition comprising: a polysaccharide; a dispersion medium; and a thickener, wherein the one or more polysaccharides are present in an amount of at least 10% by weight, the dispersion medium is a low-polarity oil, and the thickener is clay and / or silica.

Description

[Technical Field]

[0001] The present invention relates to compositions for polysaccharide delivery and methods for their preparation and use. [Background technology]

[0002] Pesticides are biologically active substances such as herbicides, fungicides and insecticides that are used by farmers and growers to control weeds and insect and fungal pests in, on, or around their crops.Typically, pesticides are provided as concentrates, which are diluted with water before application to form the final composition to be applied.Recently, it has been recognized that for some applications, it may be advantageous to use more targeted application of pesticides rather than evenly covering the entire area, such as farmland.For all types of pesticides, this may also allow for the use of much lower average levels of pesticides across the entire farmland, reducing farmer costs and reducing the amount of pesticide in the environment.This targeted spray application is known as "precision application".

[0003] "Precision application" is defined as the application of a pesticide to discrete portions of a target location rather than the entire area (broad-area spray). Types of precision application include, but are not limited to, hooded / banded application, variable rate application using prescription maps, and optical spot application. Precision application also includes this type of targeted application in non-row crop type applications, such as in-furrow application or orchard spray.

[0004] Thus, it has been discovered that polysaccharides in pesticide compositions can provide improved spray retention in precision application scenarios. The polysaccharide concentration in the spray solution is typically about 0.1 (w / w), and the spray solution can be prepared on a laboratory scale simply by dilution of an aqueous pregel (1-2 w / w%).

[0005] However, this dilution factor is inadequate on a commercial scale. For example, a 1000 L spray tank would require 50 L of 2% aqueous pregel, a dilution factor of 20, which is commercially inappropriate. Therefore, the technical challenge is how to effectively deliver polysaccharide polymers to the spray tank for their ultimate use in agrochemical applications. Summary of the Invention [Means for solving the problem]

[0006] therefore, a. Polysaccharides; b. a dispersion medium; c. thickeners and A tank mix composition comprising: one or more polysaccharides are present in an amount of at least 10% by weight; The dispersion medium is a low-polarity oil, The thickener is clay and / or silica; A composition is provided.

[0007] Thus, the compositions according to the present invention provide concentrated liquid formulation products that can be applied as "tank mixes." By "tank mix" is meant a composition that is intended to be mixed with water in a pesticide spray tank. Such tank-mix compositions typically do not contain a pesticide, but are mixed in the spray tank with a composition that contains a pesticide.

[0008] Preferably, the formulation is an oil dispersion (OD). An oil dispersion is a dispersion of solid particles in a suitable organic carrier liquid.

[0009] Compositions according to the invention have been found to exhibit improved physical stability, such as exhibiting negligible separation upon storage while retaining flowability, where negligible separation means 10% or less visible separation after 2 weeks (or even 4 weeks) at 25°C.

[0010] Such physically stable compositions have been found to form suitably thickened spray solutions upon direct dilution with water, and thus the oil dispersion serves as a convenient delivery vehicle for the polysaccharide in water.

[0011] The composition may be free or substantially free of active ingredients. DETAILED DESCRIPTION OF THE INVENTION

[0012] polysaccharide Advantageously, the one or more polysaccharides are chosen from diutan gum, guar gum, cellulose, or derivatives thereof.

[0013] Advantageously, the one or more polysaccharides are present in an amount of at least 12% by weight, such as at least 13% by weight, or at least 14% by weight.

[0014] Preferably, the polysaccharide is present in an amount of 12 to 60% by weight, even more preferably 15 to 55% by weight.

[0015] Having a polysaccharide concentration within this range increases the dilution factor significantly (for example, a 40 w / w% concentration requires only 2.5 L of product for a 1000 L spray tank, hence a dilution factor of 400).

[0016] dispersion medium The carrier fluid can be any non-aqueous liquid that has the desired non-solvent properties for the solids to be dispersed in the fluid. The carrier fluid is preferably an organic fluid, advantageously a low polarity oil.

[0017] A low polarity fluid (such as oil) is a fluid that has a dielectric constant less than 2.5.

[0018] The suspended polysaccharide should be insoluble or essentially insoluble in the dispersion medium, such as having a solubility of 700 ppm or less, preferably 500 ppm or less.

[0019] Hydrocarbons are often suitable dispersion media. For example, the low-polarity oil can be paraffinic oil or mineral oil. Suitable organic media include mineral spirits, mineral oil, aliphatic compounds, hexane, heptane, and white spirit. Preferably, the liquid is a mineral oil such as Sunspray 11N®. Preferably, the dispersion media is a low-polarity organic liquid such as the commercially available paraffinic oil Sunspray 11N®.

[0020] If the polysaccharide is insoluble in the fluid, a dispersion medium with a higher dielectric constant can be used. Advantageously, such liquids with greater polarity also have higher water solubility, allowing for more rapid dissolution of the solid when added to water. Examples are, for example, methylated rapeseed oil, oleic acid, dipropylene glycol dibenzoate, or Solvesso® 200.

[0021] The dispersion medium is preferably present in an amount of from 20 to 90% by weight, such as from 30 to 80% by weight, from 35 to 70% by weight, or even from 40 to 60% by weight.

[0022] The composition preferably contains less than 10% by weight of water, such as less than 5%, less than 1%, or even less than 0.5% by weight.

[0023] thickener Stabilizing a solid polysaccharide dispersion against settling in the dispersion medium requires the use of one or more thickeners. The thickener may be an inert solid particle. Preferably, the thickener is a clay, such as one or more organoclays.

[0024] Advantageously, the thickener is present in an amount of 0.001 to 5% by weight, such as 0.01 to 3% by weight, or 0.1 to 2% by weight.

[0025] Natural clays, such as montmorillonite, attapulgite, and illite, which exhibit substantial base exchange capacity, can be modified and made hydrophobic by treatment with long-chain amines. These are called organoclays. Organoclays can be made from natural attapulgite, smectite, hectorite, or montmorillonite clays.

[0026] Any suitable organoclay thickener may be used in the present invention.

[0027] The organoclay thickener used in the present invention may be selected from the group consisting of organically modified bentonite, hectorite, and smectite clays, such as tetraalkylammonium bentonite (e.g., Bentone™ 34), tetraalkylammonium hectorite (e.g., Bentone™ 38), tetra(alkyl / aryl)ammonium bentonite (e.g., Bentone™ SD-1, Bentone™ 52, Bentone™ 120, and Bentone™ 1000), and alkyl-arylammonium hectorite (e.g., Bentone™ SD-3). Preferably, the organoclay thickener is selected from the group consisting of tetraalkylammonium bentonite, tetraalkylammonium hectorite, and tetra(alkyl / aryl)ammonium bentonite. Preferably, the organoclay thickener is tetraalkylammonium bentonite. Preferably, the organoclay stabilizer is tetraalkylammonium hectorite. Preferably, the organoclay stabilizer is tetra(alkyl / aryl)ammonium bentonite.

[0028] The thickener, in the case of clay, may be activated prior to its inclusion. The terms "activator" and "activate" refer to the formation of a gel structure in the clay. The activator may be present in an amount of 0.3 to 10% by weight.

[0029] Chemical or polar activators can help both disperse the (organo)clay and act as an anti-settling system with good gel strength and physical stability. The term polar activator refers to molecules that can activate the organoclay stabilizer so that it forms a gel structure. For example, methanol, propylene carbonate, and water.

[0030] It has been found that the clay can be activated either in situ or before addition to the composition, preferably before addition. Examples of amine salts used to modify the clay include salts of isopropylamine, cyclohexylamine, and methylcyclohexylamine, such as bromides and acetates. When the clay is modified by treatment with an amine salt, it is preferable to incorporate an anionic surfactant into the composition. This anionic surfactant may be neutralized with a suitable amine, such as an alkyl C10 amine, a cycloalkylamine, or an alkylcycloalkylamine. Particularly preferred were alkylarylsulfonates, such as alkylbenzenesulfonates and alkylnaphthalenesulfonates. More particularly preferred were isopropylamine, cyclohexylamine, and methylcyclohexylamine salts of alkylbenzenesulfonates.

[0031] The degree of activation of the organoclay can be correlated with the gel strength and physical stability of the clay, since the amount of gelation in the system can be controlled by varying the ratio of clay and amine-neutralized surfactant, and also by replacing a portion of the amine-neutralized anionic surfactant with an appropriate amount of a conventional anionic surfactant, such as an alkali metal salt or alkaline earth metal salt of the anionic surfactant. Gelling should be sufficient to keep the substantially insoluble solid components in suspension without making the composition too thick for use.

[0032] Such blends can be produced by any conventional wet-milling process that will result in satisfactory particle size reduction in the solid material. Examples are sand mills and bead mills. Alternatively, the solid material can be dry-milled prior to incorporation into the pre-gelled material mix. Alternatively, an active ingredient of suitable particle size can be dispersed into the pre-gelled material mix by high-shear equipment.

[0033] Clays suitable for use in low-polarity organic systems can be activated with certain emulsifiers instead of polar species. In these situations, activation with an emulsifier can result in an anti-settling system with better physical stability and / or longer storage life compared to activation using a polar activator. Furthermore, the addition of a glycol ether can improve the physical stability of the dispersion. While any suitable glycol ether can be used, preferred examples include Dowanol PnB, propylene glycol, and n-monobutyl ether. The ratio of glycol ether to organoclay stabilizer can be 100:1 to 1:100 by weight, preferably 10:1 to 1:10 w / w, such as about 2:1 w / w. The glycol ether can be added in addition to or instead of the polar activator.

[0034] Suitable organoclay thickeners for use with low polarity liquids are organically modified attapulgite, hectorite, smectite, bentonite or montmorillonite clays. The clay is preferably organically modified to make it organophilic and suitable for use in organic media.

[0035] Also suitable thickeners are silica, preferably fumed silica (eg, Cab-O-Sil), or precipitated silica (Sipernat 50™); aluminum stearate; and / or hydrogenated oils.

[0036] Furthermore, mixtures of these thickeners may be used and advantageously the composition may comprise clay and silica, an example of which would be a mixture of Bentone and silica (for example in a ratio of 3:1 to 1:3).

[0037] emulsifier Emulsifiers may be added to the formulations of the present invention. The term "emulsifier" is used herein to encompass all forms of surfactants (e.g., anionic, nonionic, and zwitterionic).

[0038] The emulsifier is used in the composition to emulsify the water-insoluble organic liquid and promote the release of the dispersed solid into the aqueous phase, thereby efficiently and quickly developing the desired rheological properties.Therefore, the emulsifier can assist this process.In principle, any emulsifier can be used.

[0039] The use of such emulsifiers may also activate the organoclay thickener and may include alkyl ethoxylates, alkyl ethoxylate phosphate esters, alkyl sulfates, alkyl ammonium salts, and castor oil ethoxylates.

[0040] Anionic surfactants may be used as part of the gel system (described above), balanced in a conventional manner with nonionic surfactants to provide optimal emulsification of such formulations over a wide range of use conditions. Suitable nonionic surfactants that may be included in the compositions of the present invention are fatty acid esters condensed with ethylene and / or propylene oxide, condensation products of fatty alcohols, fatty acid amides, or fatty acid amines, alkyl-, alkenyl-, or polyaryl-substituted phenols with ethylene and / or propylene oxide, fatty esters of polyhydric alcohol ethers, such as sorbitan fatty acid esters, condensation products of such esters with ethylene oxide, such as polyoxyethylene sorbitan fatty acid esters, block copolymers of ethylene oxide and propylene oxide, ethoxylated lanolin alcohols, or ethoxylated lanolin acids.

[0041] Advantageously, the emulsifier is Emulsogen M®.

[0042] The emulsifier may be present in an amount of 0.5 to 30% by weight, such as 0.6 to 25% by weight, 0.7 to 20% by weight, 0.8 to 15% by weight, or even 1 to 10% by weight.

[0043] Compositions and Uses Also provided is a composition comprising an active ingredient, water, and a composition as described herein, which advantageously exhibits reduced micronization. Preferably, the polysaccharide is present in an amount of 0.001 to 1% by weight.

[0044] "Droplet fragmentation" is defined as the breakup of primary droplets of nominal diameter upon impact with a surface, which results in a greater number of smaller secondary droplets that then fall outside the area of ​​initial impact. "Fragmentation reduction" is therefore defined as the percentage reduction in the total number of secondary droplets due to a change in composition or compared to a control composition.

[0045] The terms "pesticide" and "active ingredient" are used interchangeably and include herbicides, fungicides and insecticides used by farmers and growers to control weeds and insect and fungal pests in, on or around their crops.

[0046] Also provided is a precision application device in combination with the above-described micronized reduction composition.

[0047] Preferably, a method for preparing the compositions described herein is provided, which comprises high-shear mixing of polysaccharide solids with a suitable dispersion medium and thickening system under high-shear mixing. Suitable high-shear mixing can be provided by equipment well known to those skilled in the art, such as an IKA overhead mixer and a wet bead mill. Advantageously, the method is carried out at a temperature of 10°C to 80°C.

[0048] Also provided is the use of a composition as described herein as a tank mix to reduce the fragmentation of an agrochemical composition. Preferably, the composition as described herein is used in precision agriculture applications.

[0049] Unless otherwise stated, percentages are given as percentages by total weight, and all embodiments and preferred features may be combined in any combination.

[0050] The invention is illustrated by the following non-limiting examples. [Example]

[0051] The definitions of the relevant components are shown in Table 1.

[0052] [Table 1]

[0053] Preparation of Bentone 38 pregel in Sunspray 11N A pregel of thickener and dispersion medium was prepared as follows.

[0054] A pregel of 1.5 w / w% Bentone 38 in Sunspray 11N was prepared using a temperature controlled 500 mL vessel fitted with a Silverson high shear mixer charged with Sunspray 11N (174 g) and mixed at 4000 rpm at 25°C.

[0055] Bentone 38 (3.04 g) was added and mixed for 10 minutes at 25° C. Propylene carbonate (0.30 g) was added and mixed for 10 minutes at 25° C. Finally, Emulsogen M (22.8 g) was added and mixed for an additional 10 minutes at 7500 rpm, then cooled to 20° C.

[0056] Unless otherwise stated, formulations containing Bentone 38 and Sunspray 11N use this pregel at the stated level of dilution.

[0057] Assessment of the physical stability of oil dispersions Visual inspection of the polysaccharide oil dispersion is performed for the particular storage criteria, typically at 25° C. The % separation is determined by visual inspection.

[0058] Preparation of 40 w / w% KELCO-VIS oil dispersion with Bentone 38 A 50 mL vessel equipped with an IKA overhead mixer and serrated paddle was charged with Sunspray 11N (13.5 g) and mixed at 600 rpm. Bentone 38 1.5 w / w% pregel (16.5 g) was added and mixed for 5 minutes. KELCO-VIS DG (20.0 g) powder was added over 10 minutes and mixed for an additional 15 minutes at 800 rpm.

[0059] This procedure is exemplified for diutan gum at 40 w / w% and is used for the preparation of various polysaccharide oil dispersions shown in Examples 1A-1E, 2A-2D, and 3A-3F as described in Tables 2 and 3.

[0060] Table 2 shows the % separation after 2 weeks at 25° C. for diutan gum slurries. In all cases, the dispersion medium is Sunspray 11N, the thickener is Bentone 38, and the polysaccharide is diutan gum. For all entries, the ratio of Bentone 38:Emulsogen M is 1:7.5.

[0061] [Table 2]

[0062] Therefore, it can be seen that the amount of thickener needs to be optimized in order to maintain physical stability while still ensuring fluidity.For example, 1B and 1D are physically stable and fluid compositions.In contrast, Example 1A and 1C show that physical stability is not achieved, while 1E demonstrates that excessive thickener causes the formation of non-fluid paste.

[0063] Preparation of KELCO-VIS oil dispersion at 40 w / w% with Bentone 38 and Sipernat 50 A 50 mL vessel equipped with an IKA overhead mixer and serrated paddle was charged with Sunspray 11N (13.25 g) and mixed at 600 rpm. Bentone 38 1.5 w / w% pregel (16.5 g) was added and mixed for 5 minutes. SIPERNAT 50 (0.25 g) was added and mixed for 5 minutes. KELCO-VIS DG (12.1 g) powder was added over 10 minutes and mixed at 800 rpm for an additional 15 minutes. This procedure is exemplified for diutan gum at 40 w / w% and used to prepare various polysaccharide oil dispersions described in Examples 3G-3L shown in Table 3.

[0064] Table 3 shows the % separation after 4 weeks at 25° C. for various polysaccharide compositions. For all entries, the polymer concentration is 40%, Emulsogen M is 3.75%, Bentone 38 is 0.50% or Bentone 38 (0.50%) and Sipernat 50 (0.50%), and Sunspray 11N as the dispersion medium.

[0065] [Table 3]

[0066] As can be seen in Table 3, by choosing a suitable thickener system, a variety of polysaccharides can be formulated as physically stable oil dispersions.

[0067] Dilution of polysaccharide oil dispersions in water Example 4A was prepared as follows: Diutan gum (10 g) was mixed with deionized water (990 g) under high shear mixing for 20 minutes to obtain a 1% aqueous pregel. 10 g of this 1 w / w% pregel was mixed with 90 g of deionized water to obtain a 0.10% aqueous diutan gum solution.

[0068] Example 4B was prepared by pipetting 0.50 g of 1B into water (99.50 g) under gentle stirring using a magnetic stir bar. The formulation was allowed to stand for 5 minutes to allow the polysaccharide particles to hydrate and thicken the aqueous fluid.

[0069] Example 4C was prepared by pipetting 0.25 g of 1D into water (99.75 g) under gentle stirring using a magnetic stir bar. The formulation was allowed to stand for 5 minutes to allow the polysaccharide particles to hydrate and thicken the aqueous fluid.

[0070] Table 4 shows shear viscosity data for aqueous solutions of diutan gum (0.10%) prepared using either a 1% diutan gum aqueous pregel or Examples 1B and 1D.

[0071] [Table 4]

[0072] Table 4 demonstrates that the final aqueous solutions containing diutan gum (0.10%) exhibit the same rheological properties, regardless of the preparation method employed, either an all-aqueous pregel (Example 4A) or a dilution prior to the polysaccharide oil dispersion according to the invention (Examples 4B and 4C).

[0073] Evaluation of spray retention performance The spray solutions were prepared by thoroughly mixing the required compositions as defined in the table below, in all cases the balance to 100% by weight being water.

[0074] Sulfacid Blue 5J was introduced into the spray solution at a final concentration of 0.5 w / w%.

[0075] Spray evaluation A custom spray evaluation method was developed to evaluate the effectiveness of polysaccharides in reducing the composition's fineness. A custom static spray rig was constructed, equipped with a spray nozzle operating at 3.0 ± 0.1 bar. Unless otherwise specified, the target surface was a circular synthetic fabric substrate (D = 20 mm) on a cylindrical support (20 mm x 80 mm), positioned 10 cm below the nozzle tip. This surface has a contact angle of 133 ± 2° with deionized water, which is used to simulate difficult-to-wet leaves.

[0076] The formulation was loaded into the spray rig and the operating parameters were adjusted to ensure that a 14±1 mg dose of spray solution was applied to the target. A sheet of A4 paper was placed below the supported target surface, with visualization aided by blue dye, and used to capture any unretained spray. A total of 10 spray events (e.g., 10 repetitions on 10 sheets of paper) were collected for each spray scenario.

[0077] The refinement performance was evaluated in the following manner: Ten A4 capture sheets were digitized using a Brother DS-720D scanner operating at 600 dpi. The digitized data was then analyzed using a custom ImageJ macro to collate information on droplet number, orientation, and area. Performance was evaluated by analysis of the total droplet number, where refinement reduction is characterized as a percentage reduction in the total droplet number.

[0078] Example 5A is prepared as follows: Bentone 38 1.5% pregel in Sunspray 11N (0.25 g) is pipetted into deionized water (99.25 g) and mixed gently for 5 minutes. Sulfacid blue 5J (0.50 g) is added and mixed for an additional 5 minutes, then sparged.

[0079] Examples 5B-D were prepared by pipetting 0.25 g of 3B, 3I, or 3E into water (99.25 g) under gentle stirring using a magnetic stir bar. The formulation was allowed to stand for 5 minutes to allow the polysaccharide particles to hydrate and thicken the aqueous fluid. Sulfacid Blue 5J (0.50 g) was added under gentle mixing for an additional 5 minutes.

[0080] Table 5 shows a summary of the data for the spray evaluation of various polysaccharide oil dispersions. Each spray solution was prepared by diluting a 40% polysaccharide oil dispersion in water to a final concentration of 0.10%. The control (5A) is an oil dispersion formulation without any polysaccharide present.

[0081] [Table 5]

[0082] Table 5 demonstrates that each of the polysaccharide oil dispersions of the present invention, when diluted in water, can provide the desired significant reduction in total droplet count (i.e., greater than a 50% reduction, preferably greater than an 85% reduction), and therefore reduce the fragmentation of spray droplets of the pesticide composition upon impact with a surface.

[0083] It can therefore be seen that the compositions of the present invention provide concentrated and stable polysaccharide formulations that are suitable for precision agriculture applications, among other things.

[0084] The invention is defined by the claims.

Claims

1. a. a polysaccharide; b. a dispersion medium; c. a thickener; 1. A liquid tank mix composition comprising: the one or more polysaccharides are present in an amount of at least 10% by weight; the dispersion medium is a low-polarity oil, The thickener is clay and / or silica. composition.

2. The composition of claim 1 which is an oil dispersion (OD).

3. 3. The composition of claim 1, wherein the polysaccharide is present in an amount of 15 to 55% by weight.

4. The composition according to any one of claims 1 to 3, wherein the one or more polysaccharides are selected from diutan gum, guar gum, cellulose, or derivatives thereof.

5. The composition of any one of claims 1 to 4, wherein the composition comprises less than 10% by weight of water.

6. 6. The composition of claim 5, wherein the low polarity oil is a mineral oil.

7. The composition according to any one of claims 1 to 6, wherein the thickening agents are clay and silica.

8. A composition according to any preceding claim, wherein the thickening agent is present in an amount of 0.001 to 5% by weight.

9. The composition according to any one of claims 1 to 8, further comprising (d) an emulsifier.

10. The composition of claim 9, wherein the emulsifier is present in an amount of 1 to 10%.

11. A composition comprising an active ingredient, water, and the composition of any one of claims 1 to 10, which exhibits reduced micronization.

12. The composition of claim 11, wherein the polysaccharide is present in an amount of 0.001 to 1% by weight.

13. A precision application device and a composition according to claim 11 or 12.

14. A method for preparing a composition according to any one of claims 1 to 10, comprising high shear mixing of the components.

15. 11. Use of a composition according to any one of claims 1 to 10 as a tank mix to reduce the finessing of an agrochemical composition.

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