Hydrophobic gas barrier coating

Abstract

A thixotropic composition is provided that forms a hydrophobic gas barrier coating on a surface of an agricultural product (e.g., an agricultural product) or a surface of a packaging material (e.g., a packaging material for packaging the agricultural product) to prevent dehydration and / or oxidation, and / or to prevent oxygen permeation and / or moisture loss through the packaging material. A thixotropic composition includes smectite clay, a compatibilizer, an oil and / or wax, and a solvent including a volatile solvent. Also provided are methods of making the compositions, methods of applying the compositions to hydrophobic surfaces, and uses of the compositions.

Description

(19) State Intellectual Property Office (12) Invention Patent Application (10) Application Publication Number (43) Application Publication Date (21) Application Number 202480018662.3 (22) Application Date 2024.03.13 (30) Priority Data 63 / 451,810 2023.03.13 US (85) PCT International Application Entering National Phase Date 2025.09.12 (86) PCT International Application Application Data PCT / IB2024 / 052429 2024.03.13 (87) PCT International Application Publication Data WO2024 / 189557 EN 2024.09.19 (71) Applicant Nabaco Corporation Address Texas, USA (72) Inventor G. Bill (74) Patent Agency Beijing Lusheng Law Firm 11326 Patent Attorneys: Wei Wangyang, Li Mi (51) Int.Cl. A23B 7 / 16 (2006.01) B65D 81 / 00 (2006.01) (54) Invention Title: Hydrophobic Gas Barrier Coating (57) Abstract: This invention provides a thixotropic composition that forms a hydrophobic gas barrier coating on the surface of agricultural products (e.g., agricultural products) or packaging materials (e.g., packaging materials for packaging agricultural products) to prevent dehydration and / or oxidation, and / or prevent oxygen penetration and / or moisture loss through the packaging material. The thixotropic composition comprises montmorillonite clay, a compatibilizer, oil and / or wax, and a solvent comprising a volatile solvent. Methods for preparing the composition, methods for applying the composition to a hydrophobic surface, and uses of the composition are also provided. Claims (3 pages), Description (17 pages), CN 120957605 A, 2025.11.14, CN 1 20 95 76 05 A. 1. A thixotropic composition for protecting agricultural products from dehydration and / or oxidation, comprising: (a) at least one montmorillonite clay; (b) a compatibilizer for hydrophobically modifying the montmorillonite clay; (c) an oil and / or wax; and (d) a solvent comprising a volatile solvent. 2. The thixotropic composition of claim 1, wherein the at least one montmorillonite clay is 1 wt.% to 10 wt.%, optionally 1 wt.% to 5 wt.%. 3. The thixotropic composition of claim 1 or claim 2, wherein the at least one montmorillonite clay is montmorillonite, lithium saponite, bentonite, lithium montmorillonite, or saponite; or a mixture of any two or more thereof. 4. The thixotropic composition according to any one of claims 1 to 3, wherein the compatibilizer comprises or is composed of sodium citrate; or wherein the compatibilizer comprises or is composed of monoglycerides or diglycerides of natural fats and / or monoglycerides or diesters of pentaerythritol.5. The thixotropic composition according to any one of claims 1 to 4, wherein the compatibilizer is 0.1 wt.% to 5.0 wt.%. 6. A thixotropic composition for protecting agricultural products from dehydration and / or oxidation, comprising: (a) at least one hydrophobically modified montmorillonite clay; (b) an oil and / or wax; and (c) a solvent comprising a volatile solvent. 7. The thixotropic composition according to claim 6, wherein the hydrophobic montmorillonite clay is 1 wt.% to 10 wt.%, optionally 1 wt.% to 5 wt.%. 8. The thixotropic composition according to claim 6 or claim 7, wherein the at least one hydrophobically modified montmorillonite clay is hydrophobically modified montmorillonite, lithium saponite, bentonite, lithium montmorillonite, or saponite; or a mixture of any two or more thereof. 9. The thixotropic composition according to any one of claims 1 to 8, wherein the oil and / or wax comprises plant-derived oil and / or wax, optionally wherein the oil is a vegetable oil or nut oil; or wherein the wax comprises carnauba wax or beeswax. 10. The thixotropic composition according to any one of claims 1 to 9, wherein the oil and / or wax is 1 wt.% to 10 wt.%, optionally 1 wt.% to 5 wt.%. 11. The thixotropic composition according to any one of claims 1 to 10, wherein the solvent is at least 85 wt.%, optionally 85 wt.% to 97.9 wt.%. 12. The thixotropic composition according to any one of claims 1 to 11, wherein the solvent comprises or consists of ethanol; or wherein the solvent is a mixture of ethanol and water, optionally wherein the mixture comprises 25 vol% volatile solvent and 75 vol% water. 13. The thixotropic composition according to any one of claims 1 to 12, wherein the composition is edible. 14. A method of preparing a thixotropic composition, comprising mixing montmorillonite clay, a compatibilizer for hydrophobic modification of the clay, oil and / or wax, and a solvent comprising a volatile solvent under high shear conditions. 15. A method for preparing a thixotropic composition, comprising: (a) dispersing montmorillonite clay in water; (b) mixing a compatibilizer into the montmorillonite clay in water under high shear to hydrophobically modify the montmorillonite clay; (c) filtering the hydrophobic montmorillonite clay; (d) drying the hydrophobic montmorillonite clay; (e) grinding the dried hydrophobic montmorillonite clay to form powdered hydrophobic montmorillonite clay; (f) mixing the powdered hydrophobic montmorillonite clay with oil and / or wax under high shear; and (g) adding a solvent comprising a volatile solvent. 16. The method according to claim 15, wherein the montmorillonite clay is dispersed in water to form a dispersion of 1 wt.% to 5 wt.%.17. A method for preparing a thixotropic composition, comprising: (a) wetting montmorillonite clay with water; (b) adding a compatibilizer to the wetted montmorillonite clay in a kneader equipped with an extruder head to hydrophobically modify the montmorillonite clay; (c) extruding the hydrophobic montmorillonite clay through the extruder head to form hydrophobic montmorillonite clay particles; (d) drying the hydrophobic montmorillonite clay particles; (e) grinding the dried hydrophobic montmorillonite clay particles to form powdered hydrophobic montmorillonite clay; (f) mixing the powdered hydrophobic montmorillonite clay with oil and / or wax under high shear; and (g) adding a solvent comprising a volatile solvent. 18. The method of claim 17, wherein the wetted montmorillonite clay is 30 wt.% to 90 wt.% montmorillonite clay, optionally about 85 wt.% montmorillonite clay. 19. The method of claim 17 or 18, wherein the kneader is a mixer. 20. The method of any one of claims 15 to 19, wherein step (e) further comprises sieving the powdered hydrophobic montmorillonite clay. 21. The method of any one of claims 14 to 20, wherein the montmorillonite clay constitutes 1 wt.% to 10 wt.% of the thixotropic composition; optionally, 1 wt.% to 5 wt.% of the thixotropic composition. 22. The method of any one of claims 14 to 21, wherein the compatibilizer constitutes 0.1 wt.% to 5.0 wt.% of the thixotropic composition. 23. The method of any one of claims 14 to 22, wherein the oil or wax constitutes 1 wt.% to 10 wt.% of the thixotropic composition; optionally, 1 wt.% to 5 wt.% of the thixotropic composition. 24. The method of any one of claims 14 to 23, wherein the solvent constitutes at least 85 wt.% of the thixotropic composition; optionally, 85 wt.% to 97.9 wt.% of the thixotropic composition. 25. The method according to any one of claims 14 to 24, wherein the montmorillonite clay is montmorillonite, lithium saponite, bentonite, lithium montmorillonite, or saponite; or a mixture of any two or more thereof. 26. The method according to any one of claims 14 to 25, wherein the compatibilizer comprises sodium citrate; or wherein the compatibilizer comprises monoglycerides or diglycerides of natural fats and / or monoglycerides or diesters of pentaerythritol. 27. The method according to any one of claims 14 to 26, wherein the oil and / or wax comprises plant-derived oils and / or waxes, optionally wherein the oil is a vegetable oil or nut oil; or wherein the wax comprises carnauba wax or beeswax. 28. The method according to any one of claims 14 to 27, wherein the solvent comprises ethanol or a mixture thereof; or wherein the solvent is a mixture of ethanol and water; optionally wherein the mixture comprises 25% by volume of a volatile solvent and 75% by volume of water.Claims 2 / 3 Page 3 CN 120957605 A 29. A thixotropic composition prepared by the method of any one of claims 14 to 28. 30. A method of applying a thixotropic composition to an agricultural product or its packaging material, comprising: preparing the thixotropic composition according to any one of claims 14 to 28; and applying the thixotropic composition to a hydrophobic surface of the agricultural product or its packaging material using an impregnation tank, a spray bar, or a brush bed, or any combination thereof. 31. The method of claim 30, wherein the thixotropic composition is applied using a combination of a spray bar and a brush bed, or using a combination of an impregnation tank and a brush bed. 32. A method of protecting a packaging material from oxygen penetration and / or moisture loss through the packaging material, comprising applying the thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of the packaging material. 33. A method of protecting an agricultural product from dehydration and / or oxidation, comprising applying the thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of the agricultural product. 34. A method for improving the shelf life of an agricultural product, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of the agricultural product. 35. A method for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of a packaging material intended for packaging the agricultural product; optionally, the method further comprises packaging the agricultural product in the packaging material. 36. A method for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of a packaging material encapsulating the agricultural product. 37. The method according to any one of claims 33 to 36, wherein the agricultural product is an agricultural product, such as a fruit or vegetable product, or wherein the agricultural product is cut flowers. 38. The method according to any one of claims 32 to 37, wherein the thixotropic composition is applied using a spray bar, an immersion tank, a brush bed, inkjet printing, gravure printing, or a doctor blade, or a combination thereof. 39. The method of claim 38, wherein a combination of a spray bar and a brush bed is used to apply the thixotropic composition. 40. The method of claim 38, wherein a combination of an impregnation tank and a brush bed is used to apply the thixotropic composition. 41. Use of the thixotropic composition of any one of claims 1 to 13 or 29 for protecting agricultural products with hydrophobic surfaces from dehydration and / or oxidation. 42. Use of the thixotropic composition of any one of claims 1 to 13 or 29 for improving the shelf life of agricultural products with hydrophobic surfaces.43. The use according to claim 41 or 42, wherein the agricultural product is an agricultural product, such as a fruit or vegetable product, or wherein the agricultural product is cut flowers. 44. The use of the thixotropic composition according to any one of claims 1 to 13 or 29 for protecting packaging materials from oxygen penetration and / or moisture loss through the packaging material. Claims 3 / 3 Page 4 CN 120957605 A Hydrophobic Gas Barrier Coating Technical Field

[0001] The present invention relates to a composition that forms a transparent hydrophobic gas barrier coating on a hydrophobic surface, such as the surface of an agricultural product (e.g., food, such as agricultural products, including fruits and vegetables; or cut flowers) or on the surface of packaging materials (e.g., packaging materials commonly used to package agricultural products). This composition effectively protects agricultural products from dehydration and / or oxidation, and / or prevents oxygen penetration and / or moisture loss through the packaging material. The invention also generally relates to methods for preparing the composition, methods for applying the composition to a hydrophobic surface, and uses of the composition as described herein. Background Art

[0002] Many hydrophobic surfaces would benefit from coatings that act as barriers to the movement of gases and / or water. These surfaces include, but are not limited to, the surfaces of fruits (e.g., pome fruits or tomatoes), cut flowers (e.g., roses), and packaging materials (e.g., oriented polypropylene (PP) and polyethylene (PE)).

[0003] Fruit and vegetable produce is often stored for long periods and frequently transported over long distances to reach the final point of sale for delivery to consumers. This can cause problems if produce ripens rapidly or is easily damaged during transport. Overripe or damaged fruits and vegetables are often unsellable or inedible, resulting in significant waste. Therefore, it is desirable to improve the shelf life of products by increasing the length of time they can be stored before consumption and by preventing premature ripening, damage, and / or spoilage.

[0004] For fruits and cut flowers, their shelf life is adversely affected by moisture loss and air oxidation. PP and PE packaging materials are very good at preventing moisture from migrating into or out of food. However, they have very poor oxygen barrier properties. For example, meat packaging prevents the meat from dehydrating, while in products like [unspecified products], packaging prevents moisture from seeping in. These packaging materials are often reinforced with an aluminized coating to overcome the problem of poor oxygen barrier properties. Aluminized coatings are expensive and make the packaging opaque. However, consumers want to be able to inspect most products before purchasing.

[0005] The present invention provides a solution to the problem that agricultural products (e.g., produce or cut flowers) and their packaging materials need to be protected from oxygen in addition to preventing moisture from seeping in or out. Summary of the Invention

[0006] The present invention generally relates to a composition comprising or containing a thixotropic mixture.Therefore, the compositions of the present invention are thixotropic compositions. The terms "thixotropic mixture" and "thixotropic composition" are used interchangeably herein and refer to the thixotropic compositions of the present invention. In some aspects of the invention, the thixotropic composition comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, an oil and / or a wax, and a solvent containing a volatile solvent, or comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, an oil and / or a wax, and a solvent containing a volatile solvent. In other aspects, the montmorillonite clay is hydrophobically modified (e.g., by the action of a compatibilizer), thus requiring no compatibilizer, or the mixture does not contain a compatibilizer. Therefore, in these other aspects, the present invention provides a thixotropic composition comprising at least one hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or a wax, and a solvent containing a volatile solvent, or comprises at least one hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or a wax, and a solvent containing a volatile solvent.

[0007] Therefore, according to a first aspect of the invention, a novel thixotropic composition is provided, comprising at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, an oil and / or wax, and a solvent comprising a volatile solvent. In some embodiments, the compatibilizer is an edible compatibilizer. In some embodiments, the oil and / or wax is a natural oil or wax. In some embodiments, the solvent comprises water and a volatile solvent (e.g., ethanol).

[0008] According to a second aspect of the invention, a novel thixotropic composition is provided, comprising at least one hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or wax, and a solvent comprising a volatile solvent. In some embodiments, the oil and / or wax is a natural oil or wax. In some embodiments, the thixotropic composition is edible. In some embodiments, the solvent comprises water and a volatile solvent.

[0009] As described herein, when applied to a hydrophobic surface, the thixotropic composition of the present invention forms a transparent, hydrophobic coating on the surface that also acts as a gas barrier. Therefore, the thixotropic composition of the present invention can be used to form a transparent, hydrophobic, and gas-barrier coating on a hydrophobic surface. This coating is suitable for protecting agricultural products from dehydration and / or oxidation; improving the shelf life of agricultural products; and reducing or preventing oxygen penetration and / or moisture loss through packaging materials. Agricultural products include cut flowers or foods, such as agricultural products (e.g., fruits and vegetables), and packaged agricultural products, such as packaged produce. These products have hydrophobic surfaces.

[0010] The present invention also provides a method for preparing the thixotropic composition of the present invention, and a thixotropic composition prepared by the method of the present invention.This method typically involves mixing montmorillonite clay, a compatibilizer, oils and / or waxes, and a solvent containing a volatile solvent. At least one step of the mixing process is carried out under high-shear mixing conditions; that is, at least two components of the composition are mixed together under high shear. In some aspects of the invention, all components of the composition are mixed together under high shear.

[0011] Accordingly, according to a third aspect of the invention, a method for preparing a thixotropic composition is provided, comprising mixing montmorillonite clay, a compatibilizer, oils and / or waxes, and a solvent containing a volatile solvent under high shear. In some embodiments, the method further includes applying the thixotropic composition to a hydrophobic surface of an agricultural product or packaging material.

[0012] According to a fourth aspect of the invention, a method for preparing a thixotropic composition is provided, comprising dispersing at least one montmorillonite clay in water; mixing a compatibilizer into the montmorillonite clay in water under high shear to hydrophobically modify the montmorillonite clay, thereby forming hydrophobically modified (e.g., hydrophobic) montmorillonite clay; filtering, drying, and grinding the hydrophobically modified (e.g., hydrophobic) montmorillonite clay to form a powder; mixing the powder with oil and / or wax under high shear; and adding a solvent comprising a volatile solvent. In some embodiments, the solvent comprises water and a volatile solvent (e.g., ethanol). In some embodiments, the powdered hydrophobically modified montmorillonite clay is sieved and then mixed with oil and / or wax. In some embodiments, the method further comprises applying the thixotropic composition to a hydrophobic surface of an agricultural product or packaging material.

[0013] According to a fifth aspect of the invention, a method for preparing a thixotropic composition is provided, comprising wetting montmorillonite clay with water; adding a compatibilizer to the wetted montmorillonite clay in a kneader equipped with an extruder head to hydrophobically modify the montmorillonite clay, thereby forming hydrophobically modified (e.g., hydrophobic) montmorillonite clay; extruding the hydrophobically modified (e.g., hydrophobic) montmorillonite clay through the extruder head to form “noodles” or granules (e.g., the clay can be extruded as “noodles” and then crushed or split into granules); drying and grinding the granules to form a powder; mixing the powder with oil and / or wax under high shear; and adding a solvent comprising a volatile solvent. In some embodiments, the solvent comprises water and a volatile solvent (e.g., ethanol). In some embodiments, the powdered hydrophobically modified montmorillonite clay is sieved and then mixed with oil and / or wax. In some embodiments, the method further includes applying the thixotropic composition to a hydrophobic surface of an agricultural product or packaging material.

[0014] The present invention also provides a method for applying the thixotropic composition of the present invention to a hydrophobic surface of an agricultural product or packaging material. Applying the thixotropic composition of the present invention to such hydrophobic properties imparts one or more advantageous properties, as described herein. For example, the thixotropic composition of the present invention can be used in methods for protecting agricultural products from dehydration and / or oxidation; or for improving the shelf life of agricultural products.The thixotropic composition of the present invention can be used to protect packaging materials from oxygen penetration and / or moisture loss through packaging materials (e.g., packaging materials for packaging agricultural products). Typically, these methods involve applying the thixotropic composition of the present invention to a hydrophobic surface of agricultural products and / or packaging materials as needed.

[0015] Therefore, according to a sixth aspect of the present invention, a method for protecting agricultural products from dehydration and / or oxidation is provided, comprising applying the thixotropic composition of the present invention to a hydrophobic surface of the agricultural product. Agricultural products include cut flowers or food, such as agricultural products (e.g., fruits and vegetables), and packaged agricultural products, such as packaged produce. These products have hydrophobic surfaces. In one embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, oils and / or waxes (e.g., natural oils or waxes), and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oils and / or waxes (e.g., natural oils or waxes), and a solvent comprising a volatile solvent. In some embodiments, the thixotropic composition is applied to the agricultural product via an impregnation tank, a spray bar, or a brush bed, or a combination thereof.

[0016] According to a seventh aspect of the invention, a method for improving the shelf life of an agricultural product having a hydrophobic surface is provided, comprising applying the thixotropic composition of the invention to the hydrophobic surface of the agricultural product. Agricultural products include cut flowers or foods, such as agricultural products (e.g., fruits and vegetables), and packaged agricultural products, such as packaged produce. These products have hydrophobic surfaces. In one embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, oils and / or waxes (e.g., natural oils or waxes), and a solvent comprising a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oils and / or waxes (e.g., natural oils or waxes), and a solvent containing a volatile solvent. In some embodiments, the thixotropic composition is applied to the agricultural product via an impregnation tank, a spray bar, or a brush bed, or a combination thereof.

[0017] According to an eighth aspect of the invention, a method is provided for protecting packaging materials from (e.g., reducing or even preventing) oxygen permeation and / or moisture loss through the packaging material, comprising applying the thixotropic composition of the invention to a hydrophobic surface of the packaging material.In one embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent containing a volatile solvent. In some embodiments, the thixotropic composition is applied to packaging material via an impregnation tank, a spray bar, or a brush bed, or a combination thereof.

[0018] According to a ninth aspect of the invention, a method is provided for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying the thixotropic composition of the invention to a hydrophobic surface of a packaging material intended for use in packaging agricultural products. For example, the packaging material may be used for packaging food, typically agricultural products. In one embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent containing a volatile solvent. In some embodiments, the thixotropic composition is applied to packaging material via an impregnation tank, a spray bar, or a brush bed, or a combination thereof. After applying the composition to the packaging material, the method may optionally further include using the packaging material to package the agricultural product.

[0019] According to a tenth aspect of the invention, a method is provided to protect agricultural products from dehydration and / or oxidation, or to improve the shelf life of agricultural products, comprising applying the thixotropic composition of the invention to a hydrophobic surface of a packaging material encapsulating the agricultural product. For example, the packaging material may surround food, typically agricultural products. In one embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent containing a volatile solvent. In some embodiments, the thixotropic composition is applied to packaging material via an impregnation tank, a spray bar, or a brush bed, or a combination thereof.

[0020] According to an eleventh aspect of the invention, a method is provided for applying a thixotropic composition to a hydrophobic surface of an agricultural product or its packaging material, comprising optionally preparing the thixotropic composition of the invention by any of the methods of the invention described herein; and applying the thixotropic composition to the surface of the agricultural product or its packaging material by means of an impregnation tank, a spray bar, or a brush bed, or any combination thereof. Agricultural products include cut flowers or foods, such as agricultural products (e.g., fruits and vegetables), and packaged agricultural products, such as packaged produce. These products have hydrophobic surfaces. In one embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent comprising a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent comprising a volatile solvent. In some embodiments, the thixotropic composition is prepared by any of the methods of the invention described herein and then applied to agricultural products using an impregnation tank, spray bar, or brush bed, or a combination thereof.

[0021] A twelfth aspect of the invention provides for the use of the thixotropic composition of the invention. The invention provides for the use of the thixotropic composition of the invention for protecting agricultural products having hydrophobic surfaces from dehydration and / or oxidation (e.g., for reducing or even preventing dehydration and / or oxidation of agricultural products). The invention also provides for the use of the thixotropic composition of the invention for improving the shelf life of agricultural products having hydrophobic surfaces; optionally, wherein an improvement is achieved relative to the shelf life of the same agricultural product without the use of the thixotropic composition of the invention, or relative to the shelf life of the same agricultural product coated with conventional compositions known in the art. In these uses of the invention, the agricultural product may optionally be an agricultural product, such as a fruit or vegetable product, or cut flowers. The invention also provides for the use of the thixotropic composition of the invention for protecting packaging materials from oxygen permeation and / or moisture loss through the packaging material (e.g., for reducing or even preventing oxygen permeation and / or moisture loss through the packaging material). In any of these uses of the invention, the thixotropic composition may comprise at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent comprising a volatile solvent. Alternatively, the thixotropic composition used may comprise hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent comprising a volatile solvent.Detailed Description

[0022] The following detailed descriptions are provided to enable those skilled in the art to prepare and use the invention. Specific details are set forth for purposes of explanation to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not required to practice the invention. The description of specific applications is provided only as representative examples. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be applied to other embodiments and applications without departing from the scope of the invention. The invention is not intended to be limited to the embodiments shown, but should be given the widest possible scope consistent with the principles and features disclosed herein.

[0023] Hydrophobic surfaces are prone to oxidation and moisture loss, therefore, coatings are often applied to agricultural products to improve shelf life. The invention disclosed herein addresses the problem that hydrophobic materials need to prevent dehydration and / or oxidation in addition to preventing the seepage or penetration of moisture, and allows consumers to inspect coated products before purchase. In order to coat organic agricultural products (e.g., organic fruits) to maintain the organic state of the agricultural products, a composition that is not only edible but also organic is also needed.

[0024] In a first aspect, the present invention provides a thixotropic composition comprising at least one montmorillonite clay, a compatibilizer (e.g., an edible compatibilizer) for hydrophobically modifying the montmorillonite clay, an oil and / or wax (e.g., a natural oil or wax), and a solvent comprising a volatile solvent.

[0025] When applied to a hydrophobic surface, the thixotropic composition forms a transparent hydrophobic gas barrier coating. For example, when applied to a hydrophobic surface of agricultural products (e.g., food products, such as agricultural products, including fruits and vegetables; or cut flowers), the thixotropic composition can effectively protect the agricultural products from dehydration and / or oxidation, and / or improve the shelf life of the agricultural products. When applied to a hydrophobic surface of packaging materials, the thixotropic composition can effectively protect the packaging materials from oxygen penetration and / or moisture loss through the packaging materials. If the packaging material is used to package or is intended for use with agricultural products, the thixotropic composition of the present invention provides protection against oxygen penetration and / or moisture loss through the packaging material, which can be used to protect agricultural products from dehydration and / or oxidation, and / or to improve the shelf life of agricultural products.

[0026] As used herein, the term "thixotropic" refers to a mixture having non-Newtonian fluid dynamics, whose flow characteristics (e.g., apparent viscosity) vary with shear rate and shear duration.

[0027] In some embodiments, the montmorillonite clay is montmorillonite, latonite (sodium magnesium lithium silicate, Na0.7Si8Mg5.5Li0.3O2O(OH)4), bentonite, lithium montmorillonite, or latonite, or a mixture of any two, any three, any four, or all five thereof.In some embodiments, the montmorillonite clay is selected from sodium montmorillonite, sodium bentonite, sodium lithium montmorillonite, lithium saponite, or saponite, or a mixture of any two, three, four, or all five thereof. For example, the montmorillonite clay may be sodium montmorillonite or lithium saponite.

[0028] In some embodiments, the thixotropic composition comprises 1.0 wt.% to 10.0 wt.% (percentage of the total weight of the thixotropic composition) of montmorillonite clay. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of the total weight of the thixotropic composition) of montmorillonite clay. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage by weight of the total thixotropic composition) of montmorillonite clay. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 10.0 wt.% (percentage by weight of the total thixotropic composition) of sodium montmorillonite or lithium montmorillonite. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage by weight of the total thixotropic composition) of sodium montmorillonite. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage by weight of the total thixotropic composition) of sodium montmorillonite. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of the total weight of the thixotropic composition) of lithium saponite. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage of the total weight of the thixotropic composition) of lithium saponite.

[0029] The surface portion of (unmodified) montmorillonite clay is hydrophilic, or even substantially hydrophilic. Due to its hydrophilicity, unmodified montmorillonite clay does not disperse well in oils or waxes, thus, preparing compositions comprising montmorillonite clay and oils or waxes is challenging. Therefore, a compatibilizer is included in the mixture to hydrophobically modify the montmorillonite clay in the composition. Generally, a "compatibility agent" is an organic modifier that reacts with and hydrophobically modifies a substance. In particular, as used herein, the term "compatibility agent" refers to a reagent that hydrophobically modifies ("hydrophobically") montmorillonite clay in a composition, thereby making the montmorillonite clay "hydrophobically modified".A compatibilizer reacts with montmorillonite clay to hydrophobically modify the montmorillonite clay particles, thereby making the clay compatible with the hydrophobic polymer (page 5 / 17, CN 120957605 A). Specifically, the compatibilizer reacts with the montmorillonite clay via ionic dipole bonding of OH groups to exchangeable sodium ions on the clay surface, thereby changing the surface of the montmorillonite clay from hydrophilic to hydrophobic. The hydrophobically modified montmorillonite clay (e.g., hydrophobic montmorillonite clay) has the advantageous characteristic of being oleophilic or waxophilic rather than hydrophilic. The surface of the hydrophobically modified montmorillonite clay is substantially hydrophobic and can be completely hydrophobic. Accordingly, in some embodiments, the compatibilizer transforms the montmorillonite clay into "hydrophobic montmorillonite clay".

[0030] Commonly used compatibilizers include ionic liquids. Ionic liquids can be composed of organic cations (including ammonium, phosphonium, sulfonium, imidazolium, pyrrolidinium, piperidinium, and / or pyridinium) and a combination of several organic and inorganic anions. Compatibilizers that can be used in this invention include sodium citrate, monoglycerides or diglycerides of natural fats, and / or monoesters or diesters of pentaerythritol. Therefore, in some embodiments, the thixotropic composition of this invention contains sodium citrate as a compatibilizer. In some embodiments, the compatibilizer in the thixotropic composition of this invention contains monoglycerides or diglycerides of natural fats and / or monoesters or diesters of pentaerythritol, such as octadecyl monoester of pentaerythritol. In some embodiments, the thixotropic composition contains montmorillonite and sodium citrate, such as sodium montmorillonite and sodium citrate. In some embodiments, the thixotropic composition contains lithium saponite and sodium citrate. In other embodiments, the thixotropic composition comprises montmorillonite (e.g., sodium montmorillonite) and an octadecanyl monoester of pentaerythritol.

[0031] In some embodiments, the thixotropic composition comprises 0.1 wt.% to 5.0 wt.% (percentage by weight of the total weight of the thixotropic composition) of a compatibilizer, such as 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%. Therefore, the thixotropic composition may comprise sodium citrate, monoglycerides or diglycerides of natural fatty acids, and / or monoesters or diesters of pentaerythritol (e.g., octadecyl monoester of pentaerythritol), in total amounts of 0.1 wt.% to 5.0 wt.% (percentage of the total weight of the thixotropic composition), for example 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%.In some embodiments, the thixotropic composition comprises 0.1 wt.% to 5.0 wt.% (percentage of total weight of the thixotropic composition), for example, 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%. In some embodiments, the thixotropic composition comprises 2 wt.% to 6 wt.% montmorillonite (e.g., sodium montmorillonite) and 0.5 wt.% to 5.0 wt.% (percentage of total weight of the thixotropic composition), for example, 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%. In some embodiments, the thixotropic composition comprises 2 wt.% to 6 wt.% lithium saponite and 0.5 wt.% to 5.0 wt.% (percentage of total weight of the thixotropic composition), for example 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.% sodium citrate.

[0032] In some embodiments, the compatibilizer is present in the composition as a milliequivalent value of the cation exchange capacity of montmorillonite clay. The cation exchange capacity can be measured indirectly by the methylene blue test or by ammonium exchange and Kjeldahl nitrogen determination. These methods are known in the art. The typical cation exchange capacity of montmorillonite clay is 90 milliequivalents / 100g to 100 milliequivalents / 100g.

[0033] The present invention also provides a novel thixotropic composition comprising at least one montmorillonite clay, sodium citrate, oil and / or wax, and a solvent comprising a volatile solvent. In some embodiments, the novel thixotropic composition comprises montmorillonite or lithium soapstone, sodium citrate, oil and / or wax, and a solvent containing a volatile solvent.

[0034] The thixotropic composition of the present invention comprises oil, wax, or oil and wax. In some embodiments, the oil and / or wax is a natural oil or wax. In this document, the term “natural” or “naturally occurring” means an oil or wax that is present in or derived from nature and is not manufactured or produced by humans. This term does not require that the oil or wax be “directly obtained from nature.” “Natural” or “naturally occurring” oil or wax can be a natural equivalent, but this is not necessary. Oils or waxes are generally edible, meaning that the oil or wax is safe for human or animal consumption. In some embodiments, the oil and / or wax in the thixotropic composition is derived from plants. In some embodiments, the thixotropic composition comprises vegetable oil or nut oil. Examples of oils suitable for inclusion in the compositions of the present invention include rapeseed oil, coconut oil, olive oil, and / or palm oil. In some embodiments, the thixotropic composition comprises rapeseed oil or coconut oil.In some embodiments, the thixotropic composition may alternatively or additionally comprise wax. Examples of waxes suitable for inclusion in the compositions of the present invention include beeswax, candelilla wax, and / or carnauba wax.

[0035] In some embodiments, the thixotropic composition comprises 1 wt.% to 10 wt.% (percentage of the total weight of the thixotropic composition) of oil and / or wax. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of the total weight of the thixotropic composition) of oil and / or wax. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage of the total weight of the thixotropic composition) of oil and / or wax.

[0036] In some embodiments, the weight ratio of oil and / or wax to montmorillonite clay in the thixotropic composition is about 1:1.

[0037] The thixotropic composition of the present invention also comprises a solvent, wherein the solvent comprises or is composed of a volatile solvent. As used herein, the term "volatile" refers to a liquid that readily evaporates into a gas. In some embodiments, the volatile solvent is ethanol. In other embodiments, the solvent comprises a mixture of a volatile solvent and water, such as a mixture of ethanol and water. In some embodiments, the mixture comprises 10%–50% volatile solvent and 50%–90% water. In some embodiments, the mixture comprises 25% by volume of volatile solvent and 75% by volume of water. A mixture of 25% by volume of volatile solvent and 75% by volume of water is advantageous because it promotes the mixing of montmorillonite clay and oil or wax.

[0038] In some embodiments, the solvent is present in an amount of at least 85 wt.% (percentage of the total weight of the thixotropic composition). In some embodiments, the solvent is present in an amount of 85 wt.% to 97.5 wt.% (e.g., 90 wt.% to 97.5 wt.%). In some embodiments, the solvent is present in an amount of 90 wt.% to 95 wt.% (percentage of the total weight of the thixotropic composition).

[0039] In some embodiments, the thixotropic composition is edible. As used herein, the term "edible" means an article that is safe for human or animal consumption.

[0040] In some embodiments, the thixotropic composition is organic. As used herein, the term "organic" means a component that, once applied to an agricultural product, does not alter the organic state of the agricultural product. Therefore, these components meet the standards set for organically produced agricultural products, such as the "organic" declaration established by the USDA's National Organic Program (NOP). In some embodiments, the organic composition does not contain any inorganic components, wherein, as used herein, the term "inorganic" means a component that, once applied to an agricultural product, alters the organic state of the agricultural product.

[0041] The thixotropic composition of the present invention forms a transparent coating on a hydrophobic surface (e.g., the surface of an agricultural product or the surface of packaging material encapsulating the product). As used herein, the term "transparent" refers to a coating that allows light to pass through. Thus, the coating film on the surface may be imperceptible to the human eye, or it may have a slightly "shiny" surface that distinguishes it from an uncoated product. Thus, the transparent coating can make the agricultural product clearly visible (e.g., through the coating on its surface and / or through the coated packaging material). Thick coatings of compositions comprising crosslinked bentonite clay are known in the art as UV protectants, which are at most translucent or opaque. Those skilled in the art can test whether the coating on the product surface is transparent by the naked eye or by methods known in the prior art.

[0042] The thixotropic composition of the present invention forms a hydrophobic gas barrier coating on a hydrophobic surface (e.g., the surface of an agricultural product or the surface of packaging material encapsulating the product). As used herein, a hydrophobic gas barrier refers to a coating that repels water and acts as a barrier to prevent the movement of gases through the hydrophobic surface. Therefore, a hydrophobic gas barrier coating protects the surface to which it is applied from the penetration of moisture and / or the exchange of gases (including oxygen) through the surface. Thus, when applied to the surface of agricultural products (e.g., product instructions 7 / 17 pages 11 CN 120957605 A), the hydrophobic gas barrier coating can be used to prevent product dehydration and / or oxidation. When applied to the hydrophobic surface of packaging materials, the hydrophobic gas barrier coating can be used to prevent product encapsulated within or intended to be encapsulated within packaging materials from dehydration and / or oxidation.

[0043] In a second aspect, the present invention provides a thixotropic composition comprising at least one hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oil and / or wax (e.g., natural oils or waxes), and a solvent comprising a volatile solvent. In some embodiments, the thixotropic composition comprises at least one hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oil and / or wax, and a solvent comprising water and a volatile solvent (e.g., ethanol).

[0044] The descriptions and definitions provided herein in the context of the thixotropic compositions of the first aspect of the invention also apply to the thixotropic compositions of the second aspect of the invention, and to all other aspects of the invention, including each of the methods and uses of the invention described herein.

[0045] As used herein, “hydrophobically modified montmorillonite clay” refers to montmorillonite clay that has been hydrophobically modified (“hydrophobic”). The surface of hydrophobically modified montmorillonite clay is substantially hydrophobic and may be completely hydrophobic. Therefore, in some embodiments, “hydrophobically modified montmorillonite clay” may be referred to as “hydrophobic montmorillonite clay”. Hydrophobically modified montmorillonite clay (e.g., hydrophobic montmorillonite clay) has the advantageous characteristic of being oleophilic or waxophilic rather than hydrophilic.A known method for determining whether montmorillonite clay is hydrophobic or hydrophilic is to use contact angle measurement. The contact angle of a water droplet on montmorillonite clay is measured using standard contact angle measuring equipment known in the art. Water droplets forming on a hydrophobic surface indicate that the cohesive forces associated within the droplet are greater than the forces associated with the interaction between the water and the montmorillonite clay surface. A contact angle greater than 90° between the montmorillonite clay surface and the water droplet indicates that the clay is hydrophobic.

[0046] In some embodiments, at least one hydrophobically modified montmorillonite clay is selected from hydrophobically modified (e.g., hydrophobic) montmorillonite, lithium saponite (sodium magnesium lithium silicate, Na0.7Si8Mg5.5Li0.3O2O(OH)4), bentonite, lithium montmorillonite, or saponite, or a mixture of any two, any three, any four, or all five thereof. In some embodiments, the hydrophobically modified (e.g., hydrophobic) montmorillonite clay is selected from hydrophobically modified (e.g., hydrophobic) sodium montmorillonite, sodium bentonite, sodium lithium montmorillonite, lithium soapstone (Na0.7Si8Mg5.5Li0.3O2O(OH)4), or soapstone, or a mixture of any two, three, four, or all five thereof. For example, the composition may contain hydrophobically modified sodium montmorillonite or hydrophobically modified lithium soapstone.

[0047] In some embodiments, the thixotropic composition contains 1.0 wt.% to 10.0 wt.% (percentage of the total weight of the thixotropic composition) of hydrophobically modified (e.g., hydrophobic) montmorillonite clay. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of total weight of the thixotropic composition) of hydrophobically modified (e.g., hydrophobic) montmorillonite clay. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage of total weight of the thixotropic composition) of hydrophobically modified (e.g., hydrophobic) montmorillonite clay.

[0048] In some embodiments, the oils and / or waxes in the thixotropic composition are edible and / or natural oils or waxes, as defined herein. In some embodiments, the thixotropic composition comprises 1 wt.% to 10 wt.% (percentage of total weight of the thixotropic composition) of oil or wax. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage by weight of the total thixotropic composition) of oil and / or wax. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage by weight of the total thixotropic composition) of oil and / or wax.

[0049] In some embodiments, the ratio of oil or wax to hydrophobically modified (e.g., hydrophobic) montmorillonite clay in the thixotropic composition is 1:1.

[0050] In some embodiments, the solvent consists of a volatile solvent, such as ethanol. In other embodiments, the solvent specification (page 8 / 17, CN 120957605 A) comprises a mixture of a volatile solvent (e.g., ethanol) and water. In some embodiments, the mixture comprises 10%–50% volatile solvent and 50%–90% water. In some embodiments, the mixture comprises 25% by volume volatile solvent and 75% by volume water, which advantageously promotes the mixing of montmorillonite clay and oil or wax. In some embodiments, the volatile solvent is ethanol. In some embodiments, the solvent is present in an amount of at least 85 wt.% (percentage of the total weight of the thixotropic composition), for example, 85 wt.% to 97.5 wt.%, or 90 wt.% to 97.5 wt.%, optionally 90 wt.% to 95 wt.% (percentage of the total weight of the thixotropic composition).

[0051] In some embodiments, the thixotropic composition is edible, having the meaning as defined herein. In some embodiments, the composition is organic, having the meaning as defined herein.

[0052] The thixotropic composition forms a coating on a hydrophobic surface (e.g., the surface of an agricultural product or the surface of packaging material encapsulating a product), the coating being transparent and acting as a hydrophobic gas barrier. These terms are defined herein.

[0053] In some embodiments of any thixotropic composition described herein, the thixotropic compositions of the present invention do not contain PVOH. For example, in some embodiments, the thixotropic compositions of the present invention do not contain any synthetic polymers and / or do not contain any semi-synthetic polymers.

[0054] The present invention also provides methods for preparing thixotropic compositions, and compositions prepared by these methods. The descriptions and definitions provided herein in the context of the thixotropic compositions of the first and second aspects of this invention also apply to the methods for preparing the thixotropic compositions of this invention.

[0055] The methods of this invention for preparing thixotropic compositions involve at least one step performed under high shear. Any method or method step involving high shear mixing described herein can be performed using any known high-shear mixer (e.g., blade mixer, Cowles dissolver, or colloid mill). High-shear mixing requires equipment with high RPM and high horsepower to ensure that the dispersing blades can reach a maximum speed of 2,500 to 5,000 feet per minute. The high-shear mixing process may take 1 to 2 hours. For mixing smaller batches of the composition, a high-shear mixer can be used. High shear forces can also be applied by extrusion, as described herein.High-shear mixing methods are advantageous because they enable rapid mixing of montmorillonite clay and solvent (as well as other components, if present) to form thixotropic mixtures, such as a uniformly dispersed dispersion of montmorillonite clay particles (lamellae). When using standard mixing methods that do not involve high shear (e.g., a can with a paddle mixer), the mixing of montmorillonite clay and solvent never fully disperses the montmorillonite clay to form a uniformly dispersed mixture. This is because the montmorillonite clay lamellars are held together in a stacked form by numerous weak bonds (e.g., hydrogen bonds and ionic dipole interactions), which together form a large cohesive force. Standard mixing is insufficient to overcome this cohesive energy. When using methods involving high shear, the increased energy and large forces generated by high shear are sufficient to break the forces holding these montmorillonite clay lamellars together. Therefore, the method of preparing the compositions of the present invention using high shear is highly efficient. High-shear mixing reduces the viscosity of the thixotropic composition, promoting the mixing and reaction of the compatibilizer to convert the montmorillonite clay from hydrophilic to hydrophobic. High-shear mixing can also be used to incorporate oils and / or waxes into thixotropic mixtures, as described herein.

[0056] Therefore, in a third aspect, the present invention provides a method for preparing a thixotropic composition comprising at least one montmorillonite clay, a compatibilizer, an oil and / or wax, and a solvent comprising a volatile solvent. The method comprises mixing montmorillonite clay, a compatibilizer, an oil or wax, and a solvent under high shear. The at least one montmorillonite clay used in the method may be any montmorillonite clay described herein. Similarly, the compatibilizer, oil and / or wax, and solvent comprising a volatile solvent used in the method may each be any of the compatibilizer, oil and / or wax, and solvent as defined herein.

[0057] In some embodiments, the method comprises mixing montmorillonite or lithium montmorillonite, sodium citrate, natural oils and / or waxes, and a solvent comprising a volatile solvent (e.g., ethanol) under high shear. In some embodiments, the method comprises mixing montmorillonite (e.g., sodium montmorillonite), sodium citrate, natural oils and / or waxes, and a solvent comprising ethanol and optionally water under high shear. In other embodiments, the method includes mixing lithium soapstone, sodium citrate, natural oils and / or waxes under high shear, and a solvent comprising ethanol and optionally water. In any of these embodiments, the natural oil is optionally rapeseed oil or coconut oil, and / or the natural wax is optionally beeswax, carnauba wax or candelilla wax.

[0058] In a fourth aspect, the present invention provides a method for preparing a thixotropic composition, comprising dispersing at least one montmorillonite clay in water; and then mixing a compatibilizer into the montmorillonite clay in water under high shear to hydrophobically modify the montmorillonite clay, thereby forming a hydrophobically modified (e.g., hydrophobic) montmorillonite clay.The hydrophobically modified (e.g., hydrophobic) montmorillonite clay is then filtered, dried, and ground into powder. The powder is then mixed with oil and / or wax under high shear, followed by the addition of a solvent containing a volatile solvent. At least one montmorillonite clay used in the method can be any montmorillonite clay described herein. Similarly, the compatibilizer, oil and / or wax, and solvent containing a volatile solvent used in the method can each be any of the compatibilizer, oil and / or wax, and solvent as defined herein.

[0059] The high-shear mixing method is as described above. High-shear mixing reduces the viscosity of the montmorillonite clay and the aqueous dispersion, promoting the mixing and reaction of the compatibilizer with the montmorillonite clay to hydrophobically modify the montmorillonite clay, thereby forming a hydrophobically modified (e.g., hydrophobic) montmorillonite clay (i.e., converting the montmorillonite clay into "hydrophobic montmorillonite clay"), as described above. The dispersion and mixing steps of the method are performed using standard equipment known in the art, such as mixers typically used for small batches, or Cowles blade or vane mixers (vane pumps) typically used for larger batches. The mixing process can be 1500-2000 feet per minute. The montmorillonite clay in the aqueous dispersion forms a thixotropic mixture, which has the meaning defined herein.

[0060] In some embodiments, the method includes dispersing montmorillonite (e.g., sodium montmorillonite) in water. In some embodiments, the method includes dispersing lithium montmorillonite in water. In some embodiments, the montmorillonite clay is dispersed in water at approximately 1.5 wt.% to 5.0 wt.% (percentage of the total weight of the thixotropic composition). In some embodiments, the montmorillonite clay is dispersed in water at 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of the total weight of the thixotropic composition). In some embodiments, the thixotropic composition comprises 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage of the total weight of the thixotropic composition) of montmorillonite clay (e.g., montmorillonite or lithium montmorillonite).

[0061] The hydrophobically modified (e.g., hydrophobic) montmorillonite clay obtained in the high-shear mixing step can be filtered using standard methods known in the art, such as using commercially available substrate and frame filter presses. The method then includes drying the filtered clay using standard methods known in the art, such as by using an external heat source, for example, using a drum dryer or spray dryer. The method then includes grinding the dried, filtered clay into a powder. Any standard grinding method known in the art can be used, such as using a hammer mill or ball mill.

[0062] The powdered hydrophobically modified (e.g., hydrophobic) montmorillonite clay is then mixed with oil and / or wax under high shear. Suitable high-shear mixing methods are described above. In some embodiments, the oil and / or wax are mixed under high shear until a homogeneous exfoliating solution is obtained.Once the energy and immense force generated by the high shear reach a level sufficient to break the large cohesive forces (due to numerous weak bonds, such as hydrogen bonds and ionic dipole interactions) that hold the montmorillonite clay flakes together, a homogeneous exfoliation solution is obtained.

[0063] In some embodiments, powdered hydrophobically modified (e.g., hydrophobic) montmorillonite clay is sieved and then mixed with oil and / or wax. For example, a sieve smaller than 325 mesh (i.e., a sieve with 325 holes / inch) can be used.

[0064] In a fifth aspect, the present invention provides a method for preparing a thixotropic composition, comprising wetting montmorillonite clay with water; adding a compatibilizer to the wetted montmorillonite clay in a kneader equipped with an extruder head to hydrophobically modify the montmorillonite clay, thereby forming hydrophobically modified (e.g., hydrophobic) montmorillonite clay; and extruding the hydrophobically modified (e.g., hydrophobic) montmorillonite clay through the extruder head to form granules. The hydrophobically modified (e.g., hydrophobic) montmorillonite clay particles are then dried and ground into powder. The powder is then mixed with oil and / or wax under high shear, followed by the addition of a solvent containing a volatile solvent.

[0065] In some embodiments, the method includes wetting the montmorillonite (e.g., sodium montmorillonite) with water. In some embodiments, the method includes wetting the lithium montmorillonite with water. In some embodiments, the wetting step produces a pellet containing 30 wt.%–90 wt.% montmorillonite clay. In some embodiments, the wetted montmorillonite clay pellet contains 80 wt.%–90 wt.% montmorillonite clay, for example, 85 wt.% montmorillonite clay.

[0066] A compatibilizer is mixed with the wetted montmorillonite clay agglomerate using a kneader (preferably a mixer) to hydrophobically modify the wetted montmorillonite clay, thereby forming a wetted, hydrophobically modified (e.g., hydrophobic) montmorillonite clay. The energy of the kneading process mixes and heats the water and montmorillonite clay to form a thixotropic mixture with a uniform distribution of montmorillonite clay particles (lamellae). Once kneaded, the hydrophobically modified wetted montmorillonite clay agglomerate is extruded through the extruder head of the kneader to form hydrophobic montmorillonite clay particles. The extrusion step imparts further high shear to the clay agglomerate. An extrusion orifice of approximately 0.25 inches is typically used.

[0067] The extruded particles of the hydrophobically modified (e.g., hydrophobic) montmorillonite clay can be dried and ground using any of the known methods described above, and optionally sieved.

[0068] In some embodiments of any method for preparing the thixotropic composition of the present invention, the montmorillonite clay is selected from montmorillonite, lithium saponite (Na0.7Si8Mg5.5Li0.3O2O(OH)4), bentonite, lithium montmorillonite or saponite, or a mixture of any two, any three, any four or all five thereof.In some embodiments of any method for preparing the thixotropic composition of the present invention, the montmorillonite clay is selected from sodium montmorillonite, sodium bentonite, sodium lithium montmorillonite, lithium saponite, or saponite, or a mixture of any two, any three, any four, or all five thereof. For example, the montmorillonite clay may contain sodium montmorillonite or lithium saponite.

[0069] In some embodiments of any method for preparing the thixotropic composition of the present invention, the thixotropic composition prepared by this method contains 1.0 wt.% to 10.0 wt.% (percentage of the total weight of the thixotropic composition) of montmorillonite clay. In some embodiments, the thixotropic composition contains 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of the total weight of the thixotropic composition) of montmorillonite clay. In some embodiments, the thixotropic composition comprises 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage of the total weight of the thixotropic composition) of montmorillonite clay.

[0070] The step of combining the montmorillonite clay with a compatibilizer hydrophobically modifies the montmorillonite clay. The term "compatibility" has the meaning as defined herein. In some embodiments of any method of the present invention for preparing the thixotropic composition, the compatibilizer is selected from sodium citrate. In other embodiments, the compatibilizer is a monoglyceride or diglyceride of a natural fatty acid, and / or a monoester or diester of pentaerythritol, such as an octadecyl monoester of pentaerythritol. In some embodiments of any method of the present invention for preparing the thixotropic composition, the montmorillonite clay is montmorillonite (e.g., sodium montmorillonite) and the compatibilizer is sodium citrate. In some embodiments of any method of the present invention for preparing the thixotropic composition, the montmorillonite clay is lithium saponite and the compatibilizer is sodium citrate.

[0071] In some embodiments of any method for preparing a thixotropic composition according to the present invention, the thixotropic composition prepared by such method comprises 0.5 wt.% to 5.0 wt.% (percentage of the total weight of the thixotropic composition) of a compatibilizer, such as 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%. In some embodiments of any method for preparing a thixotropic composition according to the present invention, the thixotropic composition comprises 0.1 wt.% to 5.0 wt.% (percentage of the total weight of the thixotropic composition), such as 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%.In some embodiments of any method for preparing the thixotropic composition of the present invention, the thixotropic composition comprises 2 wt.% to 6 wt.% of montmorillonite (e.g., sodium montmorillonite) and 0.5 wt.% to 5.0 wt.% (percentage of the total weight of the thixotropic composition), for example 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.%. In some embodiments of any method for preparing a thixotropic composition according to the present invention, the thixotropic composition comprises 2 wt.% to 6 wt.% lithium saponite and 0.5 wt.% to 5.0 wt.% (percentage of total weight of the thixotropic composition), for example, 0.1 wt.% to 2.0 wt.%, 0.1 wt.% to 1.0 wt.%, 0.1 wt.% to 0.5 wt.%, or 0.1 wt.% to 0.25 wt.% sodium citrate.

[0072] In some embodiments of any method for preparing a thixotropic composition according to the present invention, the oil and / or wax is edible or natural oil or wax as defined herein. In some embodiments of any method for preparing a thixotropic composition according to the present invention, the thixotropic composition comprises 1 wt.% to 10 wt.% (percentage of total weight of the thixotropic composition) of oil or wax. In some embodiments, the thixotropic composition comprises 1.0 wt.% to 5.0 wt.%, 1.0 wt.% to 3.0 wt.%, 1.5 wt.% to 3.0 wt.%, or 1.5 wt.% to 2.5 wt.% (percentage of the total weight of the thixotropic composition) of oil and / or wax. In some embodiments, the thixotropic composition comprises (or about) 1.5 wt.%, 2.0 wt.%, or 2.5 wt.% (percentage of the total weight of the thixotropic composition) of oil and / or wax.

[0073] In some embodiments of any method of preparing the thixotropic composition of the present invention, the oil and / or wax and montmorillonite clay are added in a 1:1 (wt / wt) ratio.

[0074] The method of preparing the thixotropic composition of the present invention employs a solvent comprising a volatile solvent, as defined herein. In some embodiments, the solvent consists of a volatile solvent (e.g., ethanol). In other embodiments, the solvent comprises a mixture of a volatile solvent (e.g., ethanol) and water. For example, the solvent mixture may contain 10 vol% to 50 vol% of volatile solvent and 50 vol% to 90 vol% of water; for example, about 25 vol% of volatile solvent and 75 vol% of water, which advantageously promotes the mixing of montmorillonite clay and oil or wax.In some embodiments, the amount of solvent added is at least 85 wt.% (percentage of the total weight of the thixotropic composition), for example, 85 wt.% to 97.5 wt.%, or 90 wt.% to 97.5 wt.%; optionally 90 wt.% to 95 wt.%.

[0075] The present invention also provides a thixotropic composition prepared by any method of the present invention. The thixotropic composition prepared by any method of the present invention may be edible and may optionally be organic. These terms have the meanings defined herein.

[0076] In some embodiments of any method of preparing a thixotropic composition of the present invention, the method further includes applying the thixotropic composition to a product having a hydrophobic surface. In some embodiments of any method of preparing a thixotropic composition of the present invention, the composition is applied using a spray bar, an immersion tank, a brush bed, inkjet printing, gravure printing, or a doctor blade or a combination thereof. For example, a composition prepared by any method of the present invention may be applied using a combination of a spray bar and a brush bed or using an immersion tank and a brush bed. The method may also include drying the composition after application (e.g., by applying heat), but more generally, allowing the composition to air dry under ambient conditions. The thixotropic composition forms a coating on the hydrophobic surface to which it is applied. The coating is transparent and acts as a hydrophobic gas barrier. These terms are defined herein.

[0077] Examples of products having at least one hydrophobic surface include agricultural products. As used herein in conjunction with all aspects of the invention, the term "agricultural product" refers to a product derived from plants and animals. Agricultural products include cut flowers and plants, and also include foods such as produce (e.g., fruits and vegetables). These products have hydrophobic surfaces. In some embodiments, an agricultural product is a produce. As used herein, the term "produce" refers to a crop produced on a farm. In some embodiments, a produce is a fruit, such as a pome fruit, a citrus fruit, or a tomato. The invention is particularly applicable to pome fruits, and more particularly to apples, pears, and / or quinces. In other embodiments, a produce is a vegetable. For example, a vegetable produce could be a cucumber or a mushroom. In other embodiments, a produce is a cut flower, such as a rose. In some embodiments, the thixotropic composition is applied to the agricultural product prior to harvest, as per page 12 / 17 of the specification (CN 120957605 A), but in other embodiments, the thixotropic composition is applied after harvest.

[0078] Other examples of products having at least one hydrophobic surface include packaging materials. As used herein in connection with all aspects of the invention, the term "packaging material" includes bags, films and wrapping materials (including shrink wrap or vacuum wrap), boxes, cartons, pallets, and other containers.Packaging materials can be made of plastics, such as polypropylene (PP) or polyethylene (PE). In some embodiments, the thixotropic composition is applied to the packaging material before it is used to package the product, but in other embodiments, the thixotropic composition is applied to the packaging material after it is used to package the product (i.e., once the product is encapsulated within the packaging material).

[0079] The present invention also provides a method of applying the thixotropic composition of the present invention to a hydrophobic surface of an agricultural product or packaging material to provide one or more technical effects as described herein. The descriptions and definitions provided herein in the context of the thixotropic compositions of the first and second aspects of the present invention also apply to the methods described below for protecting agricultural products from dehydration and / or oxidation, for improving shelf life, and / or for preventing oxygen penetration and / or moisture loss through packaging materials.

[0080] Thus, in a sixth aspect, the present invention provides a method for protecting agricultural products from dehydration and / or oxidation, comprising applying the thixotropic composition of the present invention to a hydrophobic surface of the agricultural product. For example, the method is used to protect agricultural products from dehydration and / or oxidation during storage or display. Agricultural products are as defined herein. In one embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oils and / or waxes, and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, oils and / or waxes, and a solvent containing a volatile solvent. The terms “montmorillonite clay,” “compatibility,” “hydrophobically modified montmorillonite clay,” “oils and / or waxes,” and “solvent containing a volatile solvent” are as defined herein. The thixotropic composition may be applied to agricultural products before harvest, but more typically after harvest.

[0081] Agricultural products dehydrate more rapidly under drier environmental conditions and upon exposure to air / oxygen. For example, moisture is lost from agricultural products (e.g., fruits, such as pome fruits) and vegetables during storage. The thixotropic compositions and related methods of the present invention can be used to reduce moisture loss from products by reducing the water vapor permeability of the hydrophobic surface of the product to which the thixotropic composition is applied or its packaging material. As used herein, protecting agricultural products “from dehydration” means protecting them from moisture loss (e.g., water loss). In these embodiments, “protection” from dehydration encompasses reducing or even preventing dehydration. A reduction in dehydration can be defined by comparing it to the dehydration of the same product without any coating composition (uncoated control) or to the dehydration of the same product coated with a conventional composition known in the art. Methods for observing and measuring dehydration of agricultural products are known in the art. For example, dehydration can be measured by weighing the agricultural product, where weight loss corresponds to moisture loss.In some embodiments, agricultural products coated with the thixotropic composition of the present invention exhibit at least 5% less weight loss during three weeks of storage at ambient temperature compared to the same uncoated agricultural product (control). For example, agricultural products coated with the thixotropic composition of the present invention exhibit at least 10%, 20%, 25%, 30%, 40%, 45%, 50%, or 55% less weight loss during three weeks of storage at ambient temperature compared to the same uncoated agricultural product (control).

[0082] Oxidation of agricultural products (e.g., fruits (e.g., pome fruits) and vegetables) leads to browning and softening. The thixotropic compositions and related methods of the present invention can be used to protect products from oxidation by reducing the oxygen permeability of the hydrophobic surface of the product to which the thixotropic composition is applied or its packaging material. As used herein, protecting agricultural products “from oxidation” means protecting the surface of the agricultural product from oxidation. In these embodiments, “protection” from oxidation encompasses reducing or even preventing oxidation. The reduction in oxidation can be defined by comparison with the oxidation of the same product without any coating composition (uncoated control) or with the oxidation of the same product coated with conventional compositions known in the art. Methods for observing and measuring the oxidation of agricultural products are known in the art. For example, the oxidation of agricultural products (e.g., browning and / or softening of agricultural products, such as fruits, especially pome fruits) is typically observed and measured by the naked eye.

[0083] In a seventh aspect, the present invention provides a method for improving the shelf life of agricultural products having hydrophobic surfaces, comprising applying a thixotropic composition of the present invention to the hydrophobic surface of the agricultural product. Agricultural products are as defined herein. In one embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oils and / or waxes, and a solvent comprising a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, oils and / or waxes, and a solvent comprising a volatile solvent. The terms “montmorillonite clay,” “compatibilizer,” “hydrophobically modified montmorillonite clay,” “oil and / or wax,” and “solvent containing volatile solvents” are as defined herein. Thixotropic compositions may be applied to agricultural products before harvest, but more commonly after harvest.

[0084] The shelf life of agricultural products (particularly fresh produce) can be defined as the length of time a product can be stored without becoming unsuitable for use, consumption, or sale. Within the shelf life of a product, a specified proportion of the product maintains an acceptable quality under the expected (or specified) conditions. Dehydration and / or oxidation of agricultural products can shorten their shelf life. Therefore, protecting products from dehydration and / or oxidation can be used to maintain or improve the expected shelf life of the product.An “improvement” in shelf life can be an extension of the time a product can be stored without becoming unsuitable for use, consumption, or sale. An improvement in shelf life is achieved compared to the shelf life of the same agricultural product without any coating composition (uncoated control), or compared to the shelf life of the same agricultural product coated with a conventional composition known in the art.

[0085] In an eighth aspect, the present invention provides a method for protecting packaging materials from oxygen penetration and / or moisture loss (e.g., dehydration) through a hydrophobic surface of the packaging material, comprising applying a thixotropic composition of the present invention to a hydrophobic surface of the packaging material. In one embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, an oil or wax, and a solvent comprising a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, an oil or wax, and a solvent comprising a volatile solvent. The terms “montmorillonite clay,” “compatibilizer,” “hydrophobically modified montmorillonite clay,” “oil and / or wax,” and “solvent containing volatile solvent” are as defined herein. After applying the thixotropic composition to the packaging material, the method may optionally further include packaging the agricultural product using the packaging material.

[0086] In some embodiments, the method provides protection against oxygen permeation. In other embodiments, the protection is against moisture loss, such as or including dehydration. In other embodiments, the method provides protection against both oxygen permeation and moisture loss (such as or including dehydration). The thixotropic compositions and related methods of the present invention can be used to protect packaging materials from oxygen permeation and / or moisture loss (such as dehydration) through the packaging material by reducing the oxygen and / or water vapor (e.g., water) permeability of the hydrophobic surface of the product to which the thixotropic composition is applied. In these embodiments, “protecting” the packaging material from oxygen permeation and / or moisture loss through the hydrophobic surface of the packaging material includes reducing or even preventing oxygen permeation and / or moisture loss (such as dehydration). The reduction in oxygen permeation and / or moisture loss (e.g., water loss) can be defined as compared to oxygen permeation and / or moisture loss (e.g., water loss) through the same hydrophobic surface of a packaging material without any coating composition (uncoated control), or as compared to oxygen permeation and / or moisture loss (e.g., water loss) through the same hydrophobic surface of a packaging material coated with a conventional composition known in the art.

[0087] In a ninth aspect, the present invention provides a method for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying a thixotropic composition of the present invention to a hydrophobic surface of a packaging material intended for use in packaging agricultural products. Suitable packaging materials are defined herein. Agricultural products are defined herein. Protection against dehydration and / or oxidation and improvement of shelf life are defined herein.In one embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oil or wax, and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay (see page 14 / 17 of CN 120957605 A), oil or wax, and a solvent containing a volatile solvent. The terms “montmorillonite clay,” “compatibility,” “hydrophobically modified montmorillonite clay,” “oil and / or wax,” and “solvent containing a volatile solvent” are as defined herein. After applying the thixotropic composition to a packaging material, the method may optionally further include packaging the agricultural product using the packaging material.

[0088] In a tenth aspect, the present invention provides a method for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying the thixotropic composition of the present invention to a hydrophobic surface of a packaging material encapsulating the agricultural product. For example, the packaging material may surround food, typically agricultural products. Suitable packaging materials are defined herein. This document defines agricultural products. This document defines protection against dehydration and / or oxidation and improved shelf life. In one embodiment, the thixotropic composition used in the method comprises hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oil or wax, and a solvent containing a volatile solvent. In another embodiment, the thixotropic composition used in the method comprises at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, oil or wax, and a solvent containing a volatile solvent. The terms “montmorillonite clay,” “compatibility,” “hydrophobically modified montmorillonite clay,” “oil and / or wax,” and “solvent containing a volatile solvent” are as defined herein.

[0089] In any of these methods of the invention, in some embodiments, the thixotropic composition is applied to a hydrophobic surface using an impregnation tank, a spray bar, or a brush bed, or any combination thereof. For example, a spray bar is used, and optionally a spray bar and a brush bed are used to apply the composition.

[0090] In a twelfth aspect, the invention provides for use with the thixotropic compositions of the invention. This invention provides the use of the thixotropic compositions of the invention for protecting agricultural products with hydrophobic surfaces from dehydration and / or oxidation (e.g., for reducing or even preventing dehydration and / or oxidation of agricultural products). The invention also provides the use of the thixotropic compositions of the invention for improving the shelf life of agricultural products with hydrophobic surfaces; optionally, the improvement is achieved relative to the shelf life of the same agricultural product without the use of the thixotropic compositions of the invention, or relative to the shelf life of the same agricultural product coated with conventional compositions known in the art. In these uses of the invention, the agricultural product may optionally be an agricultural product, such as fruit or vegetable produce (typically pome fruits), or cut flowers.The present invention also provides the use of the thixotropic composition of the present invention for protecting packaging materials from oxygen permeation and / or moisture loss through the packaging material (e.g., for reducing or even preventing oxygen permeation and / or moisture loss through the packaging material). In any of these uses of the present invention, the thixotropic composition may comprise hydrophobically modified (e.g., hydrophobic) montmorillonite clay, oil or wax, and a solvent comprising a volatile solvent. Alternatively, the thixotropic composition used may comprise at least one montmorillonite clay, a compatibilizer for hydrophobically modifying the montmorillonite clay, oil or wax, and a solvent comprising a volatile solvent.

[0091] Example 1

[0092] An experiment was conducted in which apples were coated with a thixotropic composition comprising 25 g of lithium soapstone, 16 g of rapeseed oil, and 2 g of sodium citrate per liter of solvent. The thixotropic composition was prepared by mixing the lithium soapstone, rapeseed oil, sodium citrate, and solvent in a mixer and shearing until 80 degrees Celsius was reached. The coating was applied manually using a sprayer and allowed to dry under ambient conditions. The weight of the apples was monitored for three weeks at ambient temperature. Compared to uncoated (control) apples, the apples coated with the thixotropic composition showed an 8% reduction in weight loss.

[0093] Example 2

[0094] An experiment was conducted in which apples were coated with a thixotropic composition containing 16 g of lithium soapstone, 25 g of rapeseed oil, and 2 g of sodium citrate per liter of solvent. The thixotropic composition was prepared by mixing the lithium soapstone, rapeseed oil, sodium citrate, and solvent in a mixer and shearing until 80 degrees Celsius was reached. The coating was applied manually to the apples using a sprayer and allowed to dry under ambient conditions. The weight of the apples was monitored for three weeks at ambient temperature. Compared to uncoated (control) apples, the apples coated with the thixotropic composition showed a 25.4% reduction in weight loss. Instruction manual 15 / 17 pages 19 CN 120957605 A

[0095] Example 3

[0096] An experiment was conducted in which apples were coated with a thixotropic composition comprising 25 g montmorillonite, 15 g rapeseed oil, 3.5 g beeswax and 2 g sodium citrate per liter of solvent. The thixotropic composition was prepared by mixing the montmorillonite, rapeseed oil, beeswax, sodium citrate and solvent in a mixer and shearing until 80 degrees Celsius was reached. The coating was applied manually to the apples using a sprayer and allowed to dry under ambient conditions. The weight of the apples was monitored for three weeks at ambient temperature. Compared with uncoated (control) apples, the apples coated with the thixotropic composition showed a 45.9% reduction in weight loss.

[0097] Example 4

[0098] An experiment was conducted in which apples were coated with a thixotropic composition comprising 20 g lithium soapstone, 25 g coconut oil and 2 g sodium citrate per liter of solvent. Thixotropic compositions were prepared by mixing lithium soapstone, coconut oil, sodium citrate, and solvent in a mixer and shearing until the temperature reached 80 degrees Celsius.The coating was applied manually to the apples using a sprayer and allowed to dry under ambient conditions. The weight of the apples was monitored for three weeks at ambient temperature. Compared to uncoated (control) apples, the apples coated with the thixotropic composition showed a 31% reduction in weight loss.

[0099] Example 5

[0100] An experiment was conducted in which Bartlett pears were coated with a thixotropic composition containing 25 g sodium montmorillonite, 9.5 g pentaerythritol octadecyl monoester, and 18 g candelilla wax per liter of 75 vol% water and 25 vol% ethanol. The thixotropic composition was prepared by mixing sodium montmorillonite, pentaerythritol octadecyl monoester, candelilla wax, water, and ethanol in a mixer for 40 minutes. Using this thixotropic composition, Bartlett pears were coated using a manual sprayer and hand rubbing to simulate a spray bar and brush bed. The Bartlett pears were stored for 3 weeks, and dehydration was measured. Compared to uncoated (control) pears, pears coated with the thixotropic composition showed a 55% reduction in dehydration.

[0101] Example 6

[0102] Another experiment was conducted in which Bartlett pears were coated with a thixotropic composition comprising 25 g sodium montmorillonite, 9.5 g pentaerythritol octadecyl monoester, and 18 g candelilla wax per liter of 75 vol% water and 25 vol% ethanol. The thixotropic composition was prepared by wetting a mixture of powdered sodium montmorillonite and pentaerythritol octadecyl monoester with 15 g of water and ethanol (75 vol%:25 vol%) to prepare a wetted hydrophobic montmorillonite clay. The wetted hydrophobic montmorillonite clay was placed in a mixer and extruded. The extruded hydrophobic montmorillonite clay particles (noodles) were then dried and ground using a ball mill to form powdered hydrophobic montmorillonite clay. The powdered hydrophobic montmorillonite clay was then dispersed in a mixer in 75 vol%:25 vol% water and ethanol for 20 minutes, resulting in a solids concentration of 5.25%. Using this thixotropic composition, Bartlett pears were coated with a manual sprayer and hand rubbed to simulate a spray bar and brush bed. The Bartlett pears were refrigerated for 3 weeks, and dehydration was measured. Compared to uncoated (control) pears, the pears coated with the thixotropic composition showed a 49% reduction in dehydration.

[0103] The terms “comprising,” “including,” and “having” as used in the claims and specification herein shall be considered as indicating an open group that may include other unspecified elements. The terms “a,” “an,” and the singular forms of words shall be considered as including the plural forms of the same words, such that these terms indicate the provision of one or more something. The terms “a” or “single” may be used to indicate one and only one something. Similarly, other specific integer values, such as “two,” may be used when intended to refer to a particular quantity of things. The terms “preferred,” “ideal,” “optional,” “may,” and similar terms are used to indicate that the mentioned items, conditions, or steps are optional (non-essential) features of the invention.

[0104] The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications can be made while remaining within the spirit and scope of the invention. It will be apparent to those skilled in the art that methods, apparatuses, apparatus elements, materials, procedures and techniques other than those specifically described herein can be applied to the practice of the invention as broadly disclosed herein without resorting to excessive experimentation. The invention is intended to cover all functional equivalents known in the art of the methods, apparatuses, apparatus elements, materials, procedures and techniques described herein. Whenever a scope is disclosed, it is intended to cover all subscopes and individual values. The invention is not limited to the disclosed embodiments, including any embodiments illustrated in the drawings or illustrated in the specification, which are given by way of example rather than limitation.

[0105] Although the invention has been described with respect to a limited number of embodiments, those skilled in the art who benefit from this disclosure will understand that other embodiments can be devised without departing from the scope of the invention disclosed herein. Therefore, the scope of the invention should be limited only by the appended claims.

[0106] All references in this application, such as patent documents (including published or granted patents or equivalents), patent application publications, non-patent documents, or other source materials, are incorporated herein by reference in their entirety to the extent that each reference is at least partially inconsistent with the disclosure in this application (e.g., partially inconsistent references are incorporated by reference except for the partially inconsistent parts). Specification 17 / 17 pages 21 CN 120957605 A.

Claims

1. A thixotropic composition for protecting agricultural products from dehydration and / or oxidation, comprising: (a) At least one montmorillonite clay; (b) A compatibilizer used to hydrophobically modify the montmorillonite clay; (c) Oils and / or waxes; and (d) Solvents, which include volatile solvents.

2. The thixotropic composition according to claim 1, wherein the at least one montmorillonite clay is 1 wt.% to 10 wt.%, optionally 1 wt.% to 5 wt.%.

3. The thixotropic composition according to claim 1 or claim 2, wherein the at least one montmorillonite clay is montmorillonite, lithium saponite, bentonite, lithium montmorillonite, or saponite; or a mixture of any two or more thereof.

4. The thixotropic composition according to any one of claims 1 to 3, wherein the compatibilizer comprises or is composed of sodium citrate; or wherein the compatibilizer comprises or is composed of monoglycerides or diglycerides of natural fats and / or monoglycerides or diesters of pentaerythritol.

5. The thixotropic composition according to any one of claims 1 to 4, wherein the compatibilizer is 0.1 wt.% to 5.0 wt.%.

6. A thixotropic composition for protecting agricultural products from dehydration and / or oxidation, comprising: (a) at least one hydrophobically modified montmorillonite clay; (b) Oils and / or waxes; and (c) Solvents, which include volatile solvents.

7. The thixotropic composition according to claim 6, wherein the hydrophobic montmorillonite clay is 1 wt.% to 10 wt.%, optionally 1 wt.% to 5 wt.%.

8. The thixotropic composition according to claim 6 or claim 7, wherein the at least one hydrophobically modified montmorillonite clay is hydrophobically modified montmorillonite, lithium saponite, bentonite, lithium montmorillonite, or saponite; or a mixture of any two or more thereof.

9. The thixotropic composition according to any one of claims 1 to 8, wherein the oil and / or wax comprises plant-derived oil and / or wax, optionally wherein the oil is a vegetable oil or nut oil; or wherein the wax comprises carnauba wax or beeswax.

10. The thixotropic composition according to any one of claims 1 to 9, wherein the oil and / or wax is 1 wt.% to 10 wt.%, optionally 1 wt.% to 5 wt.%.

11. The thixotropic composition according to any one of claims 1 to 10, wherein the solvent is at least 85 wt.%, optionally from 85 wt.% to 97.9 wt.%.

12. The thixotropic composition according to any one of claims 1 to 11, wherein the solvent comprises or is composed of ethanol; or wherein the solvent is a mixture of ethanol and water, optionally wherein the mixture comprises 25% by volume of a volatile solvent and 75% by volume of water.

13. The thixotropic composition according to any one of claims 1 to 12, wherein the composition is edible.

14. A method for preparing a thixotropic composition, comprising mixing montmorillonite clay, a compatibilizer for hydrophobic modification of the clay, oil and / or wax, and a solvent containing a volatile solvent under high shear conditions.

15. A method for preparing a thixotropic composition, comprising: (a) Disperse montmorillonite clay in water; (b) The compatibilizer is mixed into montmorillonite clay in water under high shear to hydrophobically modify the montmorillonite clay; (c) Filtering hydrophobic saponin clay; (d) Dry the hydrophobic saponite clay; (e) Grind the dry hydrophobic montmorillonite clay to form powdered hydrophobic montmorillonite clay; (f) Mixing the powdered hydrophobic montmorillonite clay with oil and / or wax under high shear; and (g) Add a solvent containing a volatile solvent.

16. The method of claim 15, wherein the montmorillonite clay is dispersed in water to form a dispersion of 1 wt.% to 5 wt.%.

17. A method for preparing a thixotropic composition, comprising: (a) Moisten the montmorillonite clay with water; (b) Adding a compatibilizer to wetted montmorillonite clay in a kneader equipped with an extruder head to hydrophobically modify the montmorillonite clay. (c) Extruding hydrophobic montmorillonite clay through the extruder head to form hydrophobic montmorillonite clay particles; (d) Dry the hydrophobic saponite clay particles; (e) Grind the dried hydrophobic montmorillonite clay particles to form powdered hydrophobic montmorillonite clay. (f) Mixing the powdered hydrophobic montmorillonite clay with oil and / or wax under high shear; and (g) Add a solvent containing a volatile solvent.

18. The method according to claim 17, wherein the wetted montmorillonite clay is 30 wt.% to 90 wt.% montmorillonite clay, optionally about 85 wt.% montmorillonite clay.

19. The method according to claim 17 or 18, wherein the kneader is a mixer.

20. The method according to any one of claims 15 to 19, wherein step (e) further comprises sieving the powdered hydrophobic montmorillonite clay.

21. The method according to any one of claims 14 to 20, wherein the montmorillonite clay accounts for 1 wt.% to 10 wt.% of the thixotropic composition; optionally, it accounts for 1 wt.% to 5 wt.% of the thixotropic composition.

22. The method according to any one of claims 14 to 21, wherein the compatibilizer comprises 0.1 wt.% to 5.0 wt.% of the thixotropic composition.

23. The method according to any one of claims 14 to 22, wherein the oil or wax accounts for 1 wt.% to 10 wt.% of the thixotropic composition; optionally, it accounts for 1 wt.% to 5 wt.% of the thixotropic composition.

24. The method according to any one of claims 14 to 23, wherein the solvent comprises at least 85 wt.% of the thixotropic composition; optionally, it comprises from 85 wt.% to 97.9 wt.% of the thixotropic composition.

25. The method according to any one of claims 14 to 24, wherein the montmorillonite clay is montmorillonite, lithium saponite, bentonite, lithium montmorillonite, or saponite; or a mixture of any two or more thereof.

26. The method according to any one of claims 14 to 25, wherein the compatibilizer comprises sodium citrate; or wherein the compatibilizer comprises monoglycerides or diglycerides of natural fats and / or monoglycerides or diesters of pentaerythritol.

27. The method according to any one of claims 14 to 26, wherein the oil and / or wax comprises plant-derived oil and / or wax, optionally wherein the oil is a vegetable oil or nut oil; or wherein the wax comprises carnauba wax or beeswax.

28. The method according to any one of claims 14 to 27, wherein the solvent comprises or is composed of ethanol; or wherein the solvent is a mixture of ethanol and water; optionally wherein the mixture comprises 25% by volume of a volatile solvent and 75% by volume of water.

29. A thixotropic composition prepared by any one of claims 14 to 28.

30. A method of applying a thixotropic composition to an agricultural product or its packaging material, comprising: The preparation of the thixotropic composition according to any one of claims 14 to 28; and The thixotropic composition is applied to the hydrophobic surface of the agricultural product or its packaging material using an impregnation tank, spray bar, or brush bed, or any combination thereof.

31. The method of claim 30, wherein the thixotropic composition is applied using a combination of a spray bar and a brush bed, or a combination of an impregnation tank and a brush bed.

32. A method for protecting a packaging material from oxygen infiltration and / or moisture loss through the packaging material, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of the packaging material.

33. A method for protecting agricultural products from dehydration and / or oxidation, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of the agricultural product.

34. A method for improving the shelf life of an agricultural product, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of the agricultural product.

35. A method for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of a packaging material intended for packaging the agricultural products; Optionally, the method further includes packaging the agricultural product in the packaging material.

36. A method for protecting agricultural products from dehydration and / or oxidation, or for improving the shelf life of agricultural products, comprising applying a thixotropic composition according to any one of claims 1 to 13 or 29 to a hydrophobic surface of a packaging material encapsulating the agricultural product.

37. The method according to any one of claims 33 to 36, wherein the agricultural product is an agricultural product, such as a fruit or vegetable product, or wherein the agricultural product is cut flowers.

38. The method according to any one of claims 32 to 37, wherein the thixotropic composition is applied using a spray bar, an immersion tank, a brush bed, inkjet printing, gravure printing, or a doctor blade or a combination thereof.

39. The method of claim 38, wherein a combination of a spray bar and a brush bed is used to apply the thixotropic composition.

40. The method of claim 38, wherein the thixotropic composition is applied using a combination of an impregnation tank and a brush bed.

41. The use of the thixotropic composition according to any one of claims 1 to 13 or 29 for protecting agricultural products having hydrophobic surfaces from dehydration and / or oxidation.

42. Use of the thixotropic composition according to any one of claims 1 to 13 or 29 for improving the shelf life of agricultural products having a hydrophobic surface.

43. The use according to claim 41 or 42, wherein the agricultural product is an agricultural product, such as a fruit or vegetable product, or wherein the agricultural product is cut flowers.

44. The use of the thixotropic composition according to any one of claims 1 to 13 or 29 for protecting packaging materials from oxygen penetration and / or moisture loss through the packaging materials.