Aqueous emulsion and coating formed therewith

Abstract

The coating may be used to hinder agglomeration and dust formation when the seed is treated. An aqueous emulsion suitable for coating seeds and other substrates may comprise: an aqueous fluid; from 5% to 60% by weight, based on total solids, of at least one wax; and 0.1% to 45% by weight, based on the total solids, of at least one abietic acid, which is at least partially neutralized by at least one base. One or more additional additives may also be present in the aqueous emulsion.

Description

Background Technology

[0001] Dust formation can be problematic in many industries, resulting in everything from mere inconvenience to serious health and safety hazards. Like many small particles, dust represents a potential inhalation hazard that can lead to adverse health effects, and in some cases, fine dust particles can spontaneously combust.

[0002] Seed handling and planting represent an area where dust formation can be problematic. For example, planting equipment can cause dust drift. Seeds can also inherently be prone to dust formation because they may be small particles or contain small particles. Dust drift, also known as dust off, is a measure of particle loss from seeds during handling. High dust off values ​​indicate excessive dust formation. Excessive dust off can release active ingredients, such as fertilizers or herbicides, from the seeds or their coatings, thus affecting crop growth. Furthermore, studies have shown that excessive dust formation during seed cultivation can have negative environmental impacts, such as harmful effects on local bee colonies.

[0003] Another common problem encountered when using seeding equipment is flowability, which refers to the ease with which dry seeds slide through the interior of the seeding device. Low flowability can lead to problems such as seed clumping (sometimes referred to in the art as "bridging"), blockages in the seeding device at different locations, inconsistent seed flow through the device, and uneven seed planting (including placing multiple seeds per hole or missing seeds in some holes). All of these factors can result in inconsistent or suboptimal planting in a given plot of farmland, leading to undesirable crop yield losses.

[0004] To prevent dust formation and promote flowability, coatings are often applied to seeds, as well as other types of materials that tend to generate dust. Polymer coatings are frequently used for this purpose. While polymer coatings can inhibit dust formation and promote increased flowability in some cases, many polymer coatings are not easily dissolved or are biodegradable, thus allowing for a prolonged period of microplastic persistence in the environment. In fact, the environmental problems associated with microplastics are so significant that the European Union has mandated the phase-out of seed coatings that generate microplastics by the mid-2020s, and other countries are expected to follow suit in the coming years.

[0005] As another issue, many coatings fail to provide satisfactory dust shedding and flow properties when combined with each other, especially those that extensively utilize bio-based or biodegradable materials. Many conventional bio-based components used in seed coatings and other types of coatings are experiencing persistent supply chain problems or deliver coating performance below expectations. Therefore, there is a desire to make seed and other surface coatings more biodegradable and / or environmentally friendly by utilizing a higher percentage (or exclusively) of readily available bio-based materials, while simultaneously achieving coatings with superior performance for their intended applications. Attached Figure Description

[0006] The following figures illustrate some aspects of this disclosure and should not be considered as exclusive constructions. The subject matter of this disclosure is capable of significant modifications, alterations, combinations, and equivalents in form and function, as will occur to those skilled in the art and who benefit from this disclosure.

[0007] Figure 1 This is a diagram illustrating a system for coating seeds using a drum coater according to various embodiments of this disclosure.

[0008] Figure 2 This is a graph showing the abrasion resistance of coatings produced from several water-based emulsions of this disclosure.

[0009] Figure 3 and Figure 4 Spider diagrams showing the performance of seeds coated with a rosin-free control and seeds coated with sample E, respectively, compared with a synthetic baseline seed coating. Detailed Implementation

[0010] This disclosure generally relates to emulsion and coating technologies, and more specifically to aqueous emulsions and coatings formed therefrom that can lack microplastic generating components.

[0011] As discussed above, dust formation can be problematic in various ways, including when handling and planting seeds. Polymer-containing seed coatings and other types of polymer coatings can promote existing flowability and suppress dust formation to varying degrees, but many types of such polymer coatings are based on chemical compositions or technologies that make them microplastics. As used herein, the term "microplastic" refers to polymer particles having a maximum size of about 5 mm in any dimension, wherein the polymer is inherently a non-biological polymer (i.e., not naturally occurring), insoluble in water, and non-biodegradable. Because microplastics are a growing environmental problem, polymer coatings defined as microplastics used on both seeds and other substrates are currently being phased out. At present, few viable alternatives exist for suppressing dust formation and promoting existing flowability when forming coatings on seeds and other types of substrates, particularly using compositions that do not contain microplastics.

[0012] This disclosure provides aqueous emulsions and coatings formed therefrom, which are freely biodegradable and can be formed primarily or exclusively from biologically derived materials or utilize synthetic materials that are environmentally favorable, including biodegradable and / or water-soluble materials. In this disclosure, a material is considered water-soluble if it has a water solubility of about 2 g / L or greater at room temperature. Biodegradation can be determined by OECD test method 301D. Other standard test methods for determining biodegradation include OECD test methods 301B, C, or F, or OECD test method 310.

[0013] The thin-film coating of this disclosure can be produced on the surface of seeds and other substrates using an aqueous emulsion comprising an aqueous fluid, at least one wax, and at least one rosin acid, wherein the at least one rosin acid is at least partially neutralized by at least one base. Optionally, other additives may also be present in the thin-film coating and the aqueous emulsion, such as at least one biopolymer, at least one water-soluble polymer, or any combination thereof, as discussed in further detail below.

[0014] Specifically, an aqueous emulsion suitable for achieving the above may comprise: an aqueous fluid; at least one wax based on total solids of 5% to 60% or 10% to 60% by weight; and at least one rosin acid based on total solids of 0.1% to 45% or 3% to 45% by weight, wherein the at least one rosin acid is at least partially neutralized by at least one base. Total solids refer to all non-liquid or non-gaseous components blended into the aqueous emulsion in dissolved or dispersed (suspended) form. Additional compositional details are as follows.

[0015] The aqueous emulsions and resulting film coatings of this disclosure are substantially based on chemical components not defined as microplastics, and therefore, unlike currently used microplastic-based film coatings, do not have a prolonged period of environmental impact. At least, the aqueous emulsions of this disclosure may contain fewer microplastic-generating components than conventional coatings. Preferably, the aqueous emulsions may be microplastic-free, providing a similarly microplastic-free film coating. Advantageously, the aqueous emulsions and film coatings of this disclosure may, in some cases, incorporate all biologically derived (natural) materials to further improve environmental benefits. Even aqueous emulsions containing all biologically derived materials can form robust film coatings once dried on various types of surfaces. The film coatings can exhibit a high degree of abrasion resistance.

[0016] Thus, the aqueous emulsions of this disclosure and the resulting thin film coatings represent potentially groundbreaking technologies for forming seed coatings and coatings on other types of base substrates. Because the aqueous emulsions and thin film coatings disclosed herein use naturally occurring materials, they are more environmentally sustainable and renewable than current technologies. While the aqueous emulsions of this disclosure may be particularly advantageous for forming coated seeds, it is understood that aqueous emulsions may also be similarly advantageous for forming thin film coatings on other types of base substrates.

[0017] The aqueous fluid suitable for use in this disclosure may comprise water or water mixed with a water-miscible organic solvent (e.g., an alcohol or glycol). Such a water-miscible organic solvent may sometimes be present as an antifreeze in the aqueous emulsion by lowering the freezing point of the aqueous fluid. In other embodiments, the aqueous fluid may be free of even water-miscible organic solvents. The aqueous fluid and aqueous emulsion may be acidic, neutral, or alkaline, depending on the specific application requirements. A specific pH may be selected to maintain the emulsion in an emulsified form or to provide, for example, a specific protonated state for one or more components of the aqueous emulsion. Buffering may be performed, for example, if desired or necessary. Thus, the aqueous fluid and the resulting aqueous emulsion may have a pH ranging from about 1 to about 7, or about 2 to about 6, or about 1 to about 6, or about 6 to about 7, or about 6 to about 8, or about 7 to about 8, or about 7 to about 14, or about 8 to about 14, or about 8 to about 12, or about 7 to about 9. Preferably, in order to maintain at least partial neutralization of at least one rosin acid, the aqueous emulsion may have a pH of about 5 or greater, or about 6 or greater, or about 7 or greater, or about 8 or greater, for example, about 5 to about 10, or about 7 to about 12, or about 7.5 to about 11, or about 8 to about 11.5.

[0018] The aqueous fluid may be present in the aqueous emulsion described herein in an amount of up to about 90 wt%, or up to about 80 wt%, or up to about 70 wt%, or up to about 60 wt%, or up to about 50 wt%, or up to about 40 wt%, or up to about 30 wt%, or up to about 20 wt%, or up to about 15 wt%, for example about 5 wt% to about 20 wt%, or about 10 wt% to about 25 wt%, or about 10 wt% to about 30 wt%, or about 15 wt% to about 25 wt%, or about 50 wt% to about 80 wt%, each as measured based on the total mass of the aqueous emulsion.

[0019] The aqueous emulsions described herein may contain a high loading of total solids, some of which may be at least partially dissolved in the aqueous fluid, and some of which may be dispersed or emulsified as particles in the aqueous fluid of the aqueous emulsion. For example, in a non-limiting example of the aqueous emulsions disclosed herein, waxes may be dispersed as particles, and depending on the degree of neutralization, at least one rosin acid may be dispersed as particles and / or at least partially dissolved in the aqueous fluid of the aqueous emulsion. In illustrative embodiments, the aqueous emulsions described herein may contain about 5% to about 70% by weight of solids, or 5% to about 70% by weight of solids, or about 5% to about 60% by weight of solids, or about 10% to about 60% by weight of solids, or about 15% to about 60% by weight of solids, or about 15% to about 55% by weight of solids, or about 20% to about 50% by weight of solids, or about 35% to about 55% by weight of solids, based on the total mass of the aqueous emulsion. In the above, solids refer to both dissolved solids and dispersed / emulsified solids. Aqueous fluids may constitute the mass balance within aqueous emulsions. Particulate solids (emulsified / dispersed solids) may be present in aqueous emulsions, for example, with particle sizes ranging from about 50 nm to about 5 μm or from about 100 nm to about 5 μm.

[0020] Suitable rosin acids may include acids such as abietic acid, piratic acid, or any combination thereof. Other suitable rosin acids that may exist either alone or in combination with abietic acid and / or piratic acid include, for example, neoabietic acid, dehydroabietic acid, longleaf abietic acid, L-piperidine, and isopiratic acid. One or more rosin acids may be derived from resin rosin and preferably substantially free of liquid terpenes after release from the resin rosin. When an aqueous emulsion is formed in some cases, crude resin rosin lacking liquid terpenes can be used directly as a source of one or more rosin acids.

[0021] Rosin acid or its at least partially neutralized form may be present in the aqueous emulsion described herein in amounts of up to about 50% by weight, or up to about 45% by weight, or up to about 40% by weight, or up to about 30% by weight, or up to about 20% by weight, for example, from about 0.1% by weight to 45% by weight, or from about 1% by weight to about 45% by weight, or from about 3% by weight to about 45% by weight, or from about 3% by weight to about 25% by weight, or from about 3% by weight to about 10% by weight, or from about 5% by weight to about 45% by weight, or from about 15% by weight to about 40% by weight, or from about 20% by weight to about 35% by weight, or from about 20% by weight to about 45% by weight, each as measured based on the mass of total solids in the aqueous emulsion. Based on the mass of the combination of wax, rosin acid, base and optional surfactant, rosin acid may be present in the aqueous emulsion in an amount of about 5% to about 50% by weight, or about 10% to about 20% by weight, or about 25% to about 50% by weight, or about 30% to about 40% by weight.

[0022] At least one rosin acid can be at least partially neutralized in the aqueous emulsions and film coatings disclosed herein, including complete neutralization or partial neutralization. When completely neutralized, substantially all of the at least one rosin acid is converted to the corresponding rosin acid salt (e.g., abirate, pirarate, etc.). When partially neutralized, a first portion of the at least one rosin acid is converted to at least one rosin acid salt, and at least a second portion of the at least one rosin acid remains in its free carboxylic acid form. In non-limiting examples, at least about 20% by weight, or at least about 30% by weight, or at least about 40% by weight, or at least about 50% by weight, or at least about 60% by weight, or at least about 70% by weight, or at least about 80% by weight, or at least about 90% by weight of the at least one rosin acid is neutralized with a base. Preferably, when only a portion of at least one rosin acid is neutralized, at least one rosin acid is neutralized in the following proportions: about 50% to about 95% by weight, or about 60% to about 95% by weight, or about 70% to about 90% by weight, or about 75% to about 95% by weight, or about 80% to about 95% by weight, or about 90% to about 99% by weight.

[0023] At least one abietic acid is soluble in an aqueous fluid when it is completely neutralized or substantially mostly neutralized. For example, at least one abietic acid is soluble in an aqueous fluid when at least about 80% or more, or about 85% or more, or about 90% or more, or about 95% or more, or about 97% or more, or about 99% or more are neutralized. When at least one abietic acid is not neutralized or insufficient amounts of at least one abietic acid are converted to salt form, at least a portion of at least one abietic acid can be dispersed as a plurality of solid particles in an aqueous fluid. At least one surfactant can be used to assist in the dispersion of at least one abietic acid as a plurality of solid particles in an aqueous emulsion; examples of surfactants are further discussed below.

[0024] Suitable bases for forming at least partially neutralized rosin acid may include, but are not limited to, ammonia, amines (e.g., ethanolamine, diethanolamine, triethanolamine, trimethylamine, diethylamine, dimethylethylamine, triethylamine, etc.) or alkali metal bases (e.g., NaOH, KOH, etc.). Combinations of these bases may be used. Once at least one rosin acid has been at least partially neutralized and incorporated into the aqueous emulsion as described above, the pH of the aqueous emulsion may be further adjusted if desired. Suitable pH ranges are provided above.

[0025] If desired, the crosslinking agent may be present in the aqueous emulsion. If an amine is used to neutralize at least one rosin acid, and an excess of amine groups is maintained, the excess amine groups can react with the epoxy groups in the crosslinking agent to promote covalent bond formation. Suitable examples of crosslinking agents containing epoxy groups will be familiar to those skilled in the art.

[0026] Waxes are hydrophobic organic substances found in petroleum and other oily materials, obtained through plant and animal biosynthesis or synthesis. Waxes are typically malleable solids at room temperature and may contain one or more higher alkanes (alkanes), particularly positive-chain or branched C42-carbon hydrocarbons. 16 -C 100 Alkanes or C 20 -C 50 Alkanes, lipids, and / or oils. In this disclosure, at least one wax may be dispersed as multiple solid wax particles in an aqueous fluid of an aqueous emulsion. Once a thin film coating is formed from the aqueous emulsion, the at least one wax may remain as solid wax particles.

[0027] Suitable waxes used in the disclosure herein may include, but are not limited to, paraffin waxes (including Fischer-Tropsch waxes), oxidized paraffin waxes, polyolefin waxes, oxidized polyolefin waxes, natural waxes, oxidized natural waxes, and any combination thereof. As used herein, a wax is considered “oxidized” if an oxygen-containing functional group (e.g., alcohol, carboxylic acid, epoxide, etc.) is introduced into another unsubstituted (alkane) hydrocarbon backbone. The amount of oxygen-containing functional group introduced into a particular oxidized wax may be, for example, sufficient to reduce the hydrophobicity of the wax to the degree necessary to promote the formation of an emulsion form of the wax.

[0028] Specific examples of suitable paraffin and lipid waxes for use in this disclosure may include, but are not limited to, porous paraffin wax, beeswax, hydrogenated lipids, refined waxes, semi-refined waxes, flake waxes, microcrystalline waxes, beeswax, plant-based waxes such as soybean and palm wax, carnauba wax, rice bran wax, lignite wax, sugarcane wax, sunflower wax, shellac wax, hydrogenated castor oil, poly(3-hydrobuyrate-co-3-hydroxyvalerate)), synthetic waxes such as oligomer waxes derived from linear α-olefins or copolymers thereof, Fischer-Tropsch waxes, polyolefin waxes (e.g., polyethylene wax or polypropylene wax), and any combination thereof. Suitable waxes may serve as a source of wax emulsions in aqueous fluids, which may then be further formulated with at least one rosin acid to form the aqueous emulsions described herein. Examples of wax emulsions that may be used in this disclosure include, but are not limited to, those that are not used in this disclosure. Emulsions, such as ME62330, ME93335, ME61335, ME52137 and ME24414 (Michelman).

[0029] Particularly suitable waxes for use in this disclosure may be waxes derived from biological sources (natural waxes / waxes of natural origin), such as any of the plant- or animal-based waxes listed above, or may also be biodegradable waxes. Therefore, in a particular embodiment, at least one wax may comprise or consist of at least one wax of natural origin as disclosed herein. However, it is understood that some synthetic waxes (e.g., some Fischer-Tropsch waxes) also allow for maintaining microplastic-free formulations and may be similarly suitable for use in this disclosure. Therefore, in a more specific example of this disclosure, at least one wax may comprise or consist of: at least one wax of natural origin (e.g., carnauba wax, rice bran wax, lignite wax, plant waxes such as soybean or palm wax, beeswax, sugarcane wax, sunflower wax, etc.), at least one Fischer-Tropsch wax, or any combination thereof.

[0030] Suitable waxes for use in aqueous emulsions incorporated in this disclosure may have a melting point of about 50°C or greater and an average particle size (diameter) when emulsified ranging from about 50,000 nm (50 micrometers), or about 1,000 nm, or about 500 nm, for example about 300 nm or less, or about 200 nm or less, or about 100 nm or less, preferably ranging from about 10 nm to about 100 nm, or about 25 nm to about 50 nm, or about 50 nm to about 90 nm, or about 20 nm to about 75 nm.

[0031] The wax may be present in the aqueous emulsion described herein in an amount of up to about 60 wt%, or up to about 50 wt%, or up to about 40 wt%, or up to about 30 wt%, for example, about 5 wt% to about 60 wt%, or about 10 wt% to about 60 wt%, or about 5 wt% to about 40 wt%, or about 15 wt% to about 35 wt%, or about 20 wt% to about 30 wt%, each as measured based on the mass of total solids in the aqueous emulsion. Based on the combined mass of the wax, rosin acid, base, and optional surfactant, the wax may be present in the aqueous emulsion in an amount of 30 wt% to about 80 wt%, or about 35 wt% to about 50 wt%, or about 40 wt% to about 60 wt%, or about 60 wt% to about 80 wt%.

[0032] The mass ratio of at least one wax to at least one rosin acid (or at least a partially neutralized form thereof) may range from about 1:1 to about 10:1, or about 1:1 to about 5:1, or about 1:1 to about 3:1, or about 1:1 to about 2:1, or about 1:1 to about 1.2:1, or about 1.2:1 to about 1.5:1, or about 1.5:1 to about 2:1.

[0033] Optionally, the aqueous emulsion and the resulting coating may contain up to about 30% by weight, or up to about 40% by weight, or up to about 50% by weight, or up to about 60% by weight, or up to about 70% by weight, additional additives, again based on total solids. Additional additives, which may be present alone or in combination with each other, include, but are not limited to, at least one biopolymer, at least one water-soluble synthetic polymer, at least one surfactant (preferably at least one anionic surfactant (optionally further combined with at least one neutral surfactant), more preferably wherein at least one anionic surfactant and / or at least one neutral surfactant is biodegradable), at least one biocide, at least one effect pigment, at least one crosslinking agent, at least one plasticizer, or any combination thereof. Other inert components such as fillers, preservatives, buffers, etc., may also be present as additional additives.

[0034] In some embodiments, the aqueous emulsion and the resulting coating may comprise at least one biopolymer, at least one water-soluble synthetic polymer, or any combination thereof. Preferably, at least one biopolymer and / or at least one water-soluble synthetic polymer may be biodegradable. Biodegradability may be evaluated as described above.

[0035] Examples of synthetic polymers exhibiting water solubility and / or biodegradability suitable for use in the disclosure herein include, but are not limited to, polyethylene glycol, polyvinylpyrrolidone, polyvinyl alcohol, poly(meth)acrylic acid, polylactic acid, polyglycolic acid, any copolymers thereof, or any combination thereof. While poly(meth)acrylic acid may be considered to constitute microplastics within some jurisdictions, such polymers can be used in aqueous emulsions and coatings where it is not necessary to maintain microplastic-free standards, or suitable comonomers can be introduced into poly(meth)acrylic acid to promote water solubility or biodegradability. Suitable copolymers of the aforementioned polymers may, for example, include any comonomer that allows the parent polymer to maintain water solubility and / or biodegradability. In some instances, the comonomer may be vinyl acetate. In more particular embodiments, the aqueous emulsion may comprise one or more of the following: polyvinyl alcohol, polyvinylpyrrolidone, vinylpyrrolidone-co-vinyl acetate copolymer, or any combination thereof.

[0036] If included, the plasticizer may be present in the aqueous emulsion described herein in an amount of up to about 30% by weight, or up to about 20% by weight, or up to about 15% by weight, or up to about 10% by weight, or up to about 5% by weight, or up to about 1% by weight, for example about 1% by weight to about 30% by weight, or about 10% by weight to about 30% by weight, or about 5% by weight to about 25% by weight, or about 15% by weight to about 25% by weight, as measured based on the total solids in the aqueous emulsion.

[0037] The aqueous emulsions disclosed herein may contain suitable plasticizers. Suitable examples of plasticizers are not particularly limited, except that they are dispersed in the aqueous emulsions of this disclosure and, once deposited on the surface of a base substrate and dried, promote robust film formation. Some examples of suitable plasticizers may be of biological origin, although non-biological plasticizers may also be used. Specific examples of suitable plasticizers may include, but are not limited to, epoxidized soybean oil, epoxidized linseed oil, castor oil, tannic acid, milk protein, polyethylene glycol, or any combination thereof. Further examples of suitable plasticizers may include, for example, epoxidized sunflower oil, cashew nut shells and modified cashew nut shells, glycidyl ether, chlorinated and phosphate / ester-based plant-based plasticizers, phosphaphenanthrene-modified vegetable oils, tung oil esters containing hydroxyl and nitrogen groups, dimethyl oleate-based plasticizers, citrate esters, etc.

[0038] If included, the plasticizer may be present in the aqueous emulsion described herein in an amount of up to about 10% by weight, or up to about 5% by weight, or up to about 4% by weight, or up to about 3% by weight, or up to about 2% by weight, or up to about 1% by weight, for example about 0.1% by weight to about 1.5% by weight, or about 0.5% by weight to about 2% by weight, or about 0.7% by weight to about 1.7% by weight, or about 0.8% by weight to about 2% by weight, as measured based on the total solids in the aqueous emulsion.

[0039] Additional components may also be present in the aqueous emulsions disclosed herein, such as one or more of the following: effect pigments (colorants), dyes, optical brighteners, crosslinking agents, defoamers, antistatic agents, dispersants, thickeners, fillers, biocides, herbicides, rheology modifiers (e.g., hydrophobically modified ethoxylated polyurethanes and similar rheology-modified polymers), flow aids, lubricants, preservatives (e.g., benzisothiazolinone, methylisothiazolinone, methylchloroisothiazolinone, etc.), coalescence aids, other emulsifying polymers, buffers, cosolvents, surfactants, and any combination thereof. Such additional components may be present in amounts conventionally found in aqueous emulsions used in coating applications. Other examples of additional components that may be present when using aqueous emulsions to form thin film coatings on seeds include, but are not limited to, fertilizers, nutrients, moisture modifiers, etc. The total amount of additional components may be up to about 30% by weight based on the total solids in the aqueous emulsion. It is not necessary for all of the aforementioned additional components to be present in a given aqueous emulsion or thin film coating. Zero, one, or more of each type of additional component may be present in any combination within the aqueous emulsions and thin film coatings of this disclosure. Suitable examples of these additional components will be familiar to those skilled in the art of emulsions and coatings.

[0040] When used, additional components can be selected independently of each other to modify one or more properties of the aqueous emulsion (e.g., to promote the formation of a thin film coating) or to enhance its suitability for a given application. For example, when used as a coating for other types of surfaces where seeding or coloring is important, one or more effect pigments or dyes may be present in the aqueous emulsion. In other cases, such as when used to form a primer coating on other surfaces (e.g., paper or cardboard), effect pigments, dyes, and other colorants may optionally be omitted. Crosslinking agents may or may not be present when a primer coating is also formed.

[0041] The illustrative surfactants considered suitable for use in the aqueous emulsions disclosed herein are not particularly limited and may include any of cationic surfactants, anionic surfactants, neutral surfactants (nonionic surfactants), amphoteric surfactants, and any combination thereof. Preferably, to promote the dispersion of at least one rosin acid, particularly when at least one rosin acid is not completely neutralized, at least one surfactant may comprise at least one anionic surfactant and optionally at least one neutral surfactant. Suitable surfactants may be present individually in amounts of up to about 25% by weight, or up to about 20% by weight, or up to about 15% by weight, or up to about 10% by weight, or up to about 8% by weight, or up to about 5% by weight, or up to about 4% by weight, or up to about 3% by weight, or up to about 2% by weight, or up to about 1% by weight, or up to about 0.5% by weight, as measured based on total solids in the aqueous emulsion. The total amount of surfactant in the aqueous emulsion may be up to about 30% by weight, or up to about 25% by weight, or up to about 20% by weight, or up to about 15% by weight, or up to about 10% by weight, or up to about 5% by weight, or up to about 1% by weight. Illustrative nonionic surfactants suitable for use in this disclosure include, but are not limited to, alkylaryl polyether alcohols, alkylphenol ethoxylates, alkyl ethoxylates, polyoxamer, fatty acid esters (e.g., fatty acid glycerides, fatty acid dehydrated sorbitan esters, fatty acid sorbitan esters (polysorbate esters), fatty acid lecithin esters, etc.), polyethylene oxide dehydrated sorbitan fatty acid esters, and any combination thereof. Illustrative anionic surfactants suitable for use in this disclosure include, but are not limited to, alkyl ethoxylate sulfates, alkyl ethoxylate sulfonates, alkylphenol ethoxylate sulfates, alkylphenol ethoxylate sulfonates, alkyl sulfates, alkyl sulfonates, alkyl aryl sulfates, alkyl aryl sulfonates, sulfosuccinates, and any combination thereof. Phosphate anionic surfactants may also be used. Illustrative zwitterionic surfactants suitable for use in this disclosure include various betaines and sulfobetaines.

[0042] Any component in the aqueous emulsion and the coating formed therefrom may optionally be crosslinked with an organic crosslinking agent (e.g., an amine in the case of crosslinked epoxides) or with metal atoms that promote crosslinking via metal-ion complexation. Suitable examples of crosslinking agents that promote crosslinking via metal-ion complexation include, but are not limited to, zinc oxide, magnesium oxide, ammonium zirconium carbonate, and others (e.g., various transition metal compounds).

[0043] A coating (thin film coating) can be formed by: providing a base substrate; contacting the surface of the base substrate with an aqueous emulsion of this disclosure; and removing the aqueous fluid from the surface to produce a coated substrate comprising a thin film coating comprising at least one wax and at least one rosin acid. More specifically, such a coated substrate may comprise a base substrate, a thin film coating formed on the surface of the base substrate and comprising at least one wax based on 10% to 60% by weight of the total mass of the thin film coating and at least one rosin acid based on 3% to 45% by weight of the total mass of the thin film coating, wherein the at least one rosin acid is at least partially neutralized by at least one base.

[0044] The types of substrates on which the aqueous emulsions of this disclosure can be used to form thin-film coatings are not particularly limited, provided that there is sufficient adhesion between the surface of the substrate and the thin-film coating. In non-limiting examples, substrates on which the aqueous emulsions can be coated include, but are not limited to, seeds, paper, cardboard and other types of packaging, wood (e.g., for building coatings), metals (e.g., metal cans), other polymers (e.g., within polymer-based circuit board assemblies), etc. Similarly, the aqueous emulsions described herein can also be used to coat adhesives onto fibers. When used to form coatings on paper and other substrates (where the coating should be inconspicuous), the aqueous emulsions can be formulated to provide optical clarity once dry.

[0045] A variety of methods can be used to apply aqueous emulsions to a base substrate, such as dip coating, spraying, bar coating or roller coating, tumbling, or by using equipment such as size presses, water tanks, doctor blade coaters, cast iron coaters, bar coaters, air knife coaters, curtain coaters, membrane pressure coaters, flexo coaters, batch coaters, drum coaters, etc., or any combination thereof. The coating method chosen may depend on the specific type of base substrate to be coated.

[0046] In a more specific example, the base substrate may contain multiple seeds. The resulting coated seeds may contain base seeds and a thin film coating formed on the surface of the base seeds, wherein the thin film coating contains at least one wax based on a total mass of 5% to 60% or 10% to 60% of the wax and at least one rosin acid based on a total mass of the coating, wherein the at least one rosin acid is at least partially neutralized by at least one base. The aqueous emulsion may contact the multiple base seeds to form the thin film coating by spraying the aqueous emulsion onto the multiple seeds, tumbling the multiple seeds together with the aqueous emulsion, or any combination thereof.

[0047] The thin-film coating on the seed may have a coating weight of about 50 mL to about 200 mL, or about 200 mL to about 400 mL, or about 400 mL to about 900 mL, or about 900 mL to about 1350 mL per 45.4 kg of seed. Depending on the seed, the thin-film coating may have a thickness of about 0.5 micrometers to about 5.0 micrometers. Examples of seeds to which a thin-film coating may be introduced according to this disclosure include, for example, cereals, plants, ornamental plants, and fruits. More specific examples of seeds that may be coated according to this disclosure include, for example, soybean seeds, corn seeds, cotton seeds, rice seeds, oat seeds, rye seeds, barley seeds, plant seeds, wheat seeds, sunflower seeds, lettuce seeds, spinach seeds, etc.

[0048] The coating thickness of thin film coatings formed on other types of base substrates according to this disclosure can range from about 1 μm to about 400 μm, or about 10 μm to about 100 μm, or about 50 μm to about 300 μm, or about 75 μm to about 225 μm. The coating thickness can be selected based on its suitability for a given application.

[0049] Figure 1 This is a diagram illustrating various embodiments of a drum coater used for coating seeds, according to the present disclosure. (See diagram for example.) Figure 1 As shown, seeds are cleaned, sorted, and added to a supply hopper 101. The seeds flow through the supply hopper 101 to a scale 102 and then into a bowl processor 103. The supply hopper 101 and scale 102 control the rate at which seeds flow into the bowl processor 103. In the bowl processor 103, the seeds pass through an area of ​​sprayed or atomized coating material. The seeds then exit the bowl processor 103 and are fed into a mixing drum 104.

[0050] The mixing drum 104 rotates the seeds and seed coating components, thereby ensuring that each seed is substantially completely coated with the seed coating. Evaporation of the aqueous fluid may occur during this process, thereby allowing other components to be applied as a thin film coating to the outer surface of the seed. Heating and / or the application of vacuum may occur in some cases to promote faster evaporation of the aqueous fluid. The coated seeds then exit through an opening in the mixing drum 104. The coated seeds exiting the mixing drum 104 may come into contact with one or more conveyor belts 105 that transport the seeds to the bagging station 106.

[0051] The drum coater may include one or more metering pumps 107 that supply aqueous emulsions to the bowl processor 103. Specifically, as directed by the control panel 109, the metering pumps 107 draw aqueous emulsions from one or more tanks 108.

[0052] It is understood that a seed coating having the composition described herein does not necessarily need to be deposited from a single aqueous emulsion as defined above. That is, one or more components of the thin film coating, optionally in emulsion form, can be applied to multiple seeds individually or together with an aqueous emulsion lacking that one or more components. Therefore, the components constituting the thin film coating on the seeds or other type of base substrate can be coated simultaneously or substantially simultaneously onto the seeds or other surfaces, regardless of whether they were mixed together in a single aqueous emulsion prior to coating. Alternatively, the components of the thin film coating can be applied to the seeds or base substrate individually at different times. When applied to the seeds or other base substrate at different times, the thin film coating may have a concentration gradient or discontinuity relative to one or more components.

[0053] The implementation plan disclosed in this article includes:

[0054] A. Aqueous emulsion. The aqueous emulsion comprises: an aqueous fluid; at least one wax based on total solids of 5% to 60% by weight; and at least one rosin acid based on total solids of 0.1% to 45% by weight, wherein the at least one rosin acid is at least partially neutralized by at least one base.

[0055] B. Coated substrate. The coated substrate comprises: a base substrate and a thin film coating, the thin film coating being formed on the surface of the base substrate and comprising: at least one wax based on 5% to 60% by weight of the total mass of the coating; and at least one rosin acid based on 0.1% to 45% by weight of the total mass of the coating, the at least one rosin acid being at least partially neutralized by at least one base.

[0056] C. Coating method. The coating method includes: providing a base substrate; contacting the surface of the base substrate with an aqueous emulsion of A; and removing the aqueous fluid from the surface of the base substrate to produce a coated substrate having a thin film coating, said thin film coating comprising at least one wax and at least one rosin acid.

[0057] Each of the implementation schemes AC may have one or more of the following additional elements in any combination:

[0058] Element 1: At least one of the rosin acids is substantially free of liquid terpenes.

[0059] Element 2: At least one of the waxes contains at least one wax of a natural origin.

[0060] Element 3: At least one of the bases comprises a base selected from the following: ammonia, amines, alkali metal hydroxides, and any combination thereof.

[0061] Element 4: At least one of the waxes is selected from the following: at least one wax of a natural source, at least one Fischer-Tropsch wax, and any combination thereof.

[0062] Element 4A: At least one of the waxes consists of one or more waxes of natural origin.

[0063] Element 5: The wax of at least one of the natural sources contains at least carnauba wax, rice bran wax, lignite wax, soybean wax, palm wax, beeswax, sugarcane wax, sunflower wax, or any combination thereof.

[0064] Element 6: At least one of the rosin acids is completely neutralized by at least one base.

[0065] Element 7: At least one of the rosin acids is dissolved in an aqueous fluid.

[0066] Element 8: wherein the aqueous fluid contains about 15% by weight to about 70% by weight of solids based on the total mass of the aqueous emulsion.

[0067] Element 9: The aqueous emulsion further comprises at least one biopolymer, at least one water-soluble polymer, at least one surfactant, at least one biocide, at least one effector pigment, or any combination thereof.

[0068] Element 10: There is at least one biopolymer, at least one water-soluble polymer, or any combination thereof.

[0069] Element 11: There is at least one surfactant, and the at least one surfactant comprises at least one anionic surfactant, at least one neutral surfactant, or any combination thereof.

[0070] Element 12: At least one of the surfactants is biodegradable.

[0071] Element 13: The basic substrate contains multiple seeds.

[0072] Element 14: Contact includes spraying an aqueous emulsion onto multiple seeds or tumbling multiple seeds together with an aqueous emulsion.

[0073] By way of non-limiting example, exemplary combinations applicable to AC include, but are not limited to, 2, 4, 4A or 5, and 3; 2, 4, 4A or 5, and 6; 2, 4, 4A or 5, and 6 and 7; 2, 4, 4A or 5, and 8; 2, 4, 4A or 5, and 9; 2, 4, 4A or 5, and 10; 2, 4, 4A or 5, and 11; 3 and 6; 3, 6, and 7; 3 and 8; 3 and 9; 3 and 10; 3 and 11; 6 and 8; 6-8; 6 and 9; 6 and 10; 6 and 11; 8 and 9; 8 and 10; 8 and 11; 9 and 10; 9 and 11; and 10 and 11. Any of the foregoing or any of 1-12 may be further combined with 13 and / or 14.

[0074] To facilitate a better understanding of the disclosure herein, the following examples of various representative embodiments are provided. These examples should not be construed in any way as limiting or restricting the scope of this disclosure.

[0075] Example

[0076] Aqueous wax emulsions were prepared by combining the components specified in Tables 1A and 1B. The wax emulsions were combined in various ratios with aqueous abietic acid emulsions containing partially neutralized abietic acid (Tables 2A and 2B) and abietic acid solutions containing fully neutralized abietic acid (Table 3) to produce combined aqueous emulsions suitable for producing thin-film coatings. Tables 4-7 (containing partially neutralized abietic acid, samples AD) and 8-9 (containing fully neutralized abietic acid, samples EF) specify the final composition of various aqueous emulsions.

[0077] Table 1A

[0078]

[0079] Table 1B

[0080]

[0081] Table 2A

[0082]

[0083] Table 2B

[0084]

[0085] Table 3

[0086]

[0087] Table 4

[0088]

[0089]

[0090] Table 5

[0091]

[0092] Table 6

[0093]

[0094] Table 7

[0095]

[0096] Table 8

[0097]

[0098] Table 9

[0099]

[0100] Figure 2 This is a graph showing the relative abrasion resistance of a base substrate coated with a thin film coating produced from several aqueous emulsions of this disclosure, compared to a rosin-free control and a commercially available comparative sample. As shown, the thin film coatings of this disclosure offer comparable or even superior performance compared to the commercially available control. The abrasion resistance in the control thin film coating lacking rosin acid is considerably poor.

[0101] Seed coating process. The aqueous emulsion prepared as described above is coated onto corn or soybean seeds using a standard seed coating procedure. Briefly, 20 grams of a slurry containing the aqueous emulsion and pesticide is brought into contact with 1 kg of seeds in a standard seed coating apparatus. After 30 seconds of contact, the seeds are retrieved from the seed coating machine and allowed to dry for 18-24 hours.

[0102] Once the coating has dried on the surface of individual seeds, additional tests are performed to evaluate the dry flow and dust formation (dust shedding) performance of the coated seeds. To measure dry flow performance, 400 g of seeds are placed in a seed flow meter. Flow is measured as the mass of seeds flowing through the meter in 0.4 seconds. The mass is divided by the flow time to provide the reported dry flow rate. Eight dry flow measurements are performed, and the results are averaged. For Heubach dust shedding performance, 100 g of seeds are placed in a Heubach dust shedding apparatus along with a pre-weighed filter. After 300 rotational cycles, both the seeds and the filter are weighed separately. The mass collected on the filter is used to determine the reported dust shedding value.

[0103] Figure 3 and Figure 4 This is a spider diagram showing the performance of seeds coated with a rosin-free control and seeds coated with sample E, each compared to a synthetic baseline seed coating. As shown, sample E produces performance comparable to the synthetic baseline seed coating. In contrast, the rosin-free control produces worse abrasion and dry flow properties.

[0104] For all purposes permissible by law, all documents described herein are incorporated herein by reference, including any priority documents and / or test procedures, provided they do not contradict this document. As is apparent from the foregoing general description and specific embodiments, various changes may be made without departing from the spirit and scope of this disclosure, while the form of the disclosure is set forth and described. Therefore, it is not intended to limit the scope of this disclosure. For example, the compositions described herein may not contain any components or compositions not expressly stated or disclosed herein. Any method may omit any step not stated or disclosed herein. Similarly, the term “comprising” is considered synonymous with the term “including.” Whenever a method, composition, element, or group of elements is preceded by the transitional phrase “comprising,” it is understood that the same group of compositions or elements is also considered, where the description of a composition, one or more elements is preceded by the transitional phrase “consistently composed of,” “composed of,” “selected from the group of,” or “is,” and vice versa.

[0105] Unless otherwise stated, all numerical values ​​used in this specification and related claims to indicate the amount, properties (e.g., molecular weight), reaction conditions, etc., of components are to be understood as being modified by the term "about" in all cases. Therefore, unless the contrary is indicated, the numerical parameters listed in the following specification and appended claims are approximate values ​​and may vary depending on the desired properties sought to be obtained by embodiments of the invention. At least and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should be interpreted based on the reported significant figures and by applying ordinary rounding techniques.

[0106] Whenever a numerical range with a lower and upper limit is disclosed, any numerical value falling within that range and any included range are specifically disclosed. In particular, the range of each value disclosed herein (having the form “from about a to about b,” or equivalently “from about a to b,” or equivalently “from about ab”) is understood to describe each numerical value and range contained within a wider range of values. Furthermore, the terms in the claims have their ordinary, general meaning unless otherwise explicitly and clearly defined by the patentee. Additionally, the indefinite articles “a” or “an” as used in the claims are defined herein to mean one or more elements that they introduce.

[0107] This document presents one or more illustrative embodiments. For clarity, not all features of the physical implementation are described or shown in this application. It is understood that in the development of the physical implementations of this disclosure, many implementation-specific decisions must be made to achieve the developer's objectives, such as complying with system-related, business-related, governmental-related, and other constraints, which vary from implementation to implementation. While the developer's efforts may be time-consuming, such efforts will be a routine task for those skilled in the art and will benefit from this disclosure.

[0108] Therefore, this disclosure is highly suitable for achieving the aforementioned results and advantages, as well as those inherent therein. The specific embodiments disclosed above are merely illustrative, as it will be apparent to those skilled in the art and benefiting from the teachings herein that different but equivalent ways may be modified and practiced. Furthermore, the details of the constructions or designs shown herein are not intended to limit, except as described in the following claims. It will be apparent that the specific illustrative embodiments of the above disclosure may be changed, combined, or modified, and all such changes are considered to be within the scope and spirit of this disclosure. Embodiments of the illustrative disclosure herein may be appropriately practiced in the absence of any elements not specifically disclosed herein and / or any optional elements disclosed herein.

Claims

1. An aqueous emulsion comprising: an aqueous fluid; from 5 wt.% to 60 wt.% of at least one wax based on total solids; and from 0.1 wt.% to 45 wt.% of at least one rosin acid based on total solids, the at least one rosin acid being at least partially neutralized by at least one base.

2. The aqueous emulsion of claim 1, wherein the at least one rosin acid is substantially free of liquid terpenes.

3. The aqueous emulsion of claim 1, wherein the at least one wax comprises at least one naturally derived wax.

4. The aqueous emulsion of claim 1, wherein the at least one base comprises a base selected from the group consisting of aqueous ammonia, an amine, an alkali metal hydroxide, and any combination thereof.

5. The aqueous emulsion of any one of claims 1-4, wherein the at least one wax is selected from the group consisting of at least one naturally derived wax, at least one Fischer-Tropsch wax, and any combination thereof.

6. The aqueous emulsion of claim 5, wherein the at least one naturally derived wax comprises at least carnauba wax, rice bran wax, montan ester wax, soy wax, palm wax, beeswax, sugar cane wax, sunflower wax, or any combination thereof.

7. The aqueous emulsion of any one of claims 1-4, wherein the at least one wax consists of one or more naturally derived waxes.

8. The aqueous emulsion of claim 7, wherein the at least one naturally derived wax comprises at least carnauba wax, rice bran wax, montan ester wax, soy wax, palm wax, beeswax, sugar cane wax, sunflower wax, or any combination thereof.

9. The aqueous emulsion of any one of claims 1-4, wherein the at least one rosin acid is fully neutralized by the at least one base.

10. The aqueous emulsion of claim 9, wherein the at least one rosin acid is dissolved in the aqueous fluid.

11. The aqueous emulsion of any one of claims 1-4, wherein the aqueous fluid comprises from about 15 wt.% to about 70 wt.% solids based on the total mass of the aqueous emulsion.

12. The aqueous emulsion of any one of claims 1-4, further comprising: at least one biopolymer, at least one water-soluble polymer, at least one surfactant, at least one biocide, at least one effect pigment, or any combination thereof.

13. The aqueous emulsion of claim 12, wherein the at least one biopolymer, the at least one water-soluble polymer, or any combination thereof is present.

14. The aqueous emulsion of claim 12, wherein the at least one surfactant is present, and the at least one surfactant comprises at least one anionic surfactant, at least one neutral surfactant, or any combination thereof.

15. The aqueous emulsion of claim 14, wherein the at least one surfactant is biodegradable.

16. A coated substrate comprising: a base substrate; and a thin film coating formed on a surface of the base substrate and comprising: from 5 wt.% to 60 wt.% of at least one wax based on the total mass of the coating; 0.1 to 45 weight percent, based on the total mass of the coating, of at least one rosin acid, the at least one rosin acid being at least partially neutralized by at least one base.

17. The coated substrate of claim 16, wherein the at least one wax comprises at least one naturally derived wax.

18. The coated substrate of claim 16, wherein the at least one base comprises a base selected from the group consisting of aqueous ammonia, an amine, an alkali metal hydroxide, and any combination thereof.

19. The coated substrate of any one of claims 16-18, wherein the at least one wax is selected from the group consisting of at least one naturally derived wax, at least one Fischer-Tropsch wax, and any combination thereof.

20. The coated substrate of claim 19, wherein the at least one naturally derived wax comprises at least carnauba wax, rice bran wax, montan ester wax, soy wax, palm wax, beeswax, sugar cane wax, sunflower wax, or any combination thereof.

21. The coated substrate of any one of claims 16-18, wherein the at least one wax consists of one or more naturally derived waxes.

22. The coated substrate of claim 21, wherein the at least one naturally derived wax comprises at least carnauba wax, rice bran wax, montan ester wax, soy wax, palm wax, beeswax, sugar cane wax, sunflower wax, or any combination thereof.

23. The coated substrate of any one of claims 16-18, wherein the at least one rosin acid is fully neutralized by the at least one base.

24. The coated substrate of any one of claims 16-18, further comprising: at least one biopolymer, at least one water-soluble synthetic polymer, at least one surfactant, at least one biocide, at least one effect pigment, or any combination thereof.

25. The coated substrate of claim 24, wherein the at least one biopolymer, the at least one water-soluble polymer, or any combination thereof is present.

26. The coated substrate of claim 24, wherein the at least one surfactant is present, and the at least one surfactant comprises at least one anionic surfactant, at least one neutral surfactant, or any combination thereof.

27. The coated substrate of claim 26, wherein the at least one surfactant is biodegradable.

28. The coated substrate of any one of claims 16-18, wherein the base substrate comprises a plurality of seeds.

29. A method comprising: providing a base substrate; contacting a surface of the base substrate with the aqueous emulsion of any one of claims 1-4; and removing the aqueous fluid from the surface of the base substrate to produce a coated substrate having a thin film coating comprising the at least one wax and the at least one rosin acid.

30. The method of claim 29, wherein the base substrate comprises a plurality of seeds. ​ 31. The method of claim 30, wherein contacting comprises spraying the aqueous emulsion onto the plurality of seeds, or tumbling the plurality of seeds with the aqueous emulsion.

32. The method of any one of claims 29-31, wherein the at least one wax is selected from the group consisting of at least one naturally-sourced wax, at least one Fischer-Tropsch wax, and any combination thereof.

33. The method of any one of claims 29-31, wherein the at least one wax consists of one or more naturally-sourced waxes.

34. The method of any one of claims 29-31, wherein the at least one abietic acid is fully neutralized by the at least one base.

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