Hollow core granules, products incorporating the granules, and methods for preparing the granules.

Abstract

The present invention provides hollow core granules, products incorporating the hollow core granules, and a method for producing the hollow core granules. [Solution] The hollow core granules may comprise at least one wall that substantially encloses and partitions the hollow core, substantially lacking both solid and liquid, wherein the at least one wall comprises a plurality of individual particles of at least one wall-forming material, the plurality of individual particles being sufficiently cohesive and bonded together so that the at least one wall is structurally self-supporting. The hollow core granules may further comprise a binder material present in the at least one wall. The hollow core granules may be useful as a standalone material and / or may be useful in the manufacture of various products in which the hollow core granules are mixed with further components or otherwise combined. The present disclosure further provides a method for manufacturing the hollow core granules.

Description

Technical Field

[0001] The present disclosure relates to hollow core particles. The hollow core particles can include at least one wall surrounding a cavity that defines the hollow core. The at least one wall can include particles of at least one wall-forming material and can similarly include at least one binder.

Background Art

[0002] Various compounds are known for various uses in substantially solid form. Many compounds, when provided in substantially granular form, can provide uses that are limited by the available surface area. For example, some compounds can be reactive, but any reaction can occur substantially only at the surface of the particles, and much of the mass of the particles does not participate in the reaction. Further, many materials useful in solid form, substantially in granular form, can be overly heavy. For example, clay particles are commonly used in various consumer products, most notably in typical animal litter compositions. Animal litter is often sold in substantially large volumes, such as may be required to fill a litter tray. Due to this typical arrangement, the volume of animal litter required for commercial packaging can be overly heavy. Further, there is still a need in the art for means to provide chemical products, compounds, and compositions in solid form, substantially in granular form, while also providing improved properties.

Summary of the Invention

Means for Solving the Problems

[0003] This disclosure relates to hollow core granules. Hollow core granules can be a design structure in which multiple particles of one or more wall-forming materials are aggregated, agglomerated, or otherwise joined together in the form of at least one wall substantially surrounding a cavity that partitions a hollow core. Hollow core granules are distinguished from the natural form of the wall-forming material in that the combination of individual particles as a wall surrounding the hollow core can cause the granules to exhibit improved properties compared to the wall-forming material in its natural form (i.e., not existing as multiple particles surrounding a hollow core). This makes hollow core granules available for various uses in various products that at least partially contain multiple hollow core granules. This disclosure also provides a method for forming such a hollow core structure and various products or manufactured articles that can contain hollow core granules.

[0004] In one or more embodiments, this disclosure may relate to hollow core granules. Although the structure is described in terms of a singular granule, such terminology is used for convenience, and it is understood that the various properties and uses of hollow core granules are not limited to a single granule. Rather, multiple granules exhibiting substantially the same properties and having substantially the same uses are encompassed in this disclosure. Furthermore, in use, it is understood that multiple granules are typically used to form a product or to perform a particular use. Nevertheless, the subject matter may be identified with a single granule or multiple granules.

[0005] In exemplary embodiments, the hollow core granules according to this disclosure may include at least one wall that substantially encloses and partitions the hollow core, substantially lacking both solid and liquid, the at least one wall comprising a plurality of individual particles of the at least one wall-forming material, the plurality of individual particles being sufficiently cohesive and bonded together such that the at least one wall is structurally self-supporting. The hollow core granules (or a plurality of hollow core granules) may in one or more embodiments be further defined with respect to one or more of the following descriptions, which may be combined as desired in any number or order, and the ability to make any particular combination of the following descriptions (or all possible combinations of the following descriptions) is immediately apparent from further disclosures herein.

[0006] At least one wall-forming material can be selected from the group consisting of clay, glass, ceramic, alumina, silicate, zeolite, carbon, metal, salt, absorbent, adsorbent, deodorant, odor inhibitor, surfactant, enzyme, bleach, oxidizing agent, reducing agent, gelling agent, flavoring agent, fragrance, abrasive, fertilizer, insecticide, pest control agent, fungicide, herbicide, antimicrobial agent, anti-adhesion agent, filler, binder, preservative, fluorescent agent, disinfectant, chelating agent, molecular binder, dye, colorant, colored particle, dust remover, and combinations thereof. At least one wall-forming material may include clay. Clay can contain bentonite. At least one wall-forming material may contain salt.

[0007] The salt can be selected from the group consisting of calcium carbonate, sodium chloride, sodium carbonate, sodium bicarbonate, sodium percarbonate, sodium sulfate, sodium carbonate peroxide, potassium chloride, magnesium carbonate, magnesium sulfate, and combinations thereof. The salt can be sodium bicarbonate. The hollow core granules according to claim 6, wherein the salt can be sodium carbonate. Salt can be sodium chloride.

[0008] At least one wall-forming material can be a fabric care composition. Fabric care compositions can be selected from the group consisting of laundry detergents, bleaches, whiteners, brighteners, stain removers, deodorizers, scent boosters, and combinations thereof. At least one wall-forming material may be an additive for the fabric care composition. At least one wall-forming material can be a pet litter composition. At least one wall-forming material can be an additive for the pet litter composition. Additives for pet litter compositions can be selected from the group consisting of fillers, flocculants, binders, preservatives, dust removers, fragrances, and mixtures thereof.

[0009] At least one wall-forming material can be configured for the absorption, adsorption, or other binding of one or more odor-causing chemicals that come into contact with the hollow core granules. At least one wall-forming material can be configured for absorption, adsorption, or other binding of an aqueous liquid that comes into contact with the hollow core granules. At least one wall-forming material can be configured for absorption, adsorption, or other binding of a non-aqueous liquid that comes into contact with the hollow core granules. At least one wall-forming material can be a pH adjusting agent.

[0010] At least one wall-forming material may contain fertilizer.

[0011] Fertilizers can be selected from a group consisting of nitrogen sources, phosphorus sources, potassium sources, micronutrient sources, and combinations thereof. Hollow core granules as fertilizer may be characterized by satisfying one or more of the following conditions: at least one wall-forming material may further include clay, and at least a portion of the fertilizer may be absorbed, adsorbed, or otherwise combined with the clay particles; at least a portion of the fertilizer may be in microencapsulated form; the fertilizer may contain at least two different fertilizers; the fertilizer may be configured for substantially immediate release; the fertilizer may be configured for controlled release.

[0012] At least one wall-forming material may contain a pest control agent. Pest control agents include bifenthrin, acephate, carbaryl, cyfluthrin, 2,4-dichlorophenoxyacetic acid, trifluralin, chlorpyrifos, arethrin, cypermethrin, disulfonate, 2,6-dichlorobenzonitrile, metrachlor, cyhalosrin, hydramethylnon, atrazine, chlorothalonil, mycrobutanil, dicamba, azadirachtin, captan, diazinon, carbofuran, methomyl, deltamethrin, propiconazole, borate, and dinote. The active agent may be selected from the group consisting of furan, dithiopyr, isoxaben, prodiamine, quinchlorac, cethoxydim, iron(III) phosphate, mancozeb, thiophanate-methyl, esfenvalerate, tebuconazole, resmethrin, glyphosate, malathion, permethrin, imidacloprid, fipronil, abamectin, spinosad, triclopyr, piperonyl butoxide, pendimethalin, oryzalin, oxadiazone, and combinations thereof.

[0013] At least one wall-forming material may further contain clay, and at least a portion of the pesticide may be absorbed, adsorbed, or otherwise combined with the clay particles. At least one wall-forming material may contain an odor masking agent.

[0014] Hollow core granules can be made hydrophilic. The hollow core granules can be made hydrophobic. The hollow core granules may further include one or more coating layers covering at least a portion of at least one wall. The hollow core granules may further include at least one binder material present in at least a portion of the interstitial space between individual particles of at least one wall-forming material.

[0015] At least one of the binders can be a hydrophilic material. At least one binder may contain polyethylene glycol (PEG) material. At least one of the binders can be a hydrophobic material. At least one binder may include a material selected from the group consisting of wax, paraffin, polycaprolactone, ethylene-vinyl acetate copolymer, polypropylene carbonate, poly(tetramethylene oxide), poly(ethylene adipate), poly(trans-butadiene), thermoplastic polyurethane, stearic acid, and combinations thereof. At least one binder can contain approximately 1% to 45% by weight, based on the total weight of the hollow core granules.

[0016] Hollow core granules can have a diameter of approximately 0.1 mm to approximately 20 mm. The diameter of the hollow core granules can be approximately 0.5 mm to 6 mm. The hollow core can have a diameter that is approximately 10% to 80% of the diameter of the hollow core granules. The diameter of the hollow core can be approximately 25% to 55% of the diameter of the hollow core granules. At least one wall can have an average thickness of approximately 0.05 mm to approximately 8 mm. The average thickness can be approximately 0.1 mm to 4 mm.

[0017] The hollow core particles can be configured such that the cavity partitioning the hollow core has a volume that is about 0.1% to about 50% of the volume of the hollow core particles. The volume of the cavity can be about 0.5% to about 10% of the volume of the hollow core particles. The hollow core particles can have a density that is at least 20% lower than the density of the wall-forming material. The density of the hollow core particles can be about 15% to about 50% lower than the density of the wall-forming material. The hollow core particles can be buoyant in water.

[0018] At least one wall can be an aggregate of individual particles of the wall-forming material. The individual particles of the wall-forming material can have an average particle size of about 0.01 mm to about 2 mm. The individual particles of the wall-forming material can have an average particle size of about 0.05 mm to about 1.0 mm. The hollow core particles can exhibit a time to substantially complete dissolution that is at least 10% faster than the time to substantially complete dissolution of at least one wall-forming material alone of the same weight.

[0019] The hollow core particles according to claim 1 can be configured to break into a plurality of portions including individual groups of wall-forming material particles upon application of an external force.

[0020] In an exemplary embodiment, the disclosure can relate to a product comprising a plurality of hollow core particles. The plurality of hollow core particles can be defined with respect to any one or two or more of the foregoing descriptions, and any further description of the hollow core particles as described herein. Further, the product comprising a plurality of hollow core particles can be further defined with respect to any one or two or more of the following descriptions, which can be combined as desired in any number or order, and the ability to make any particular combination (or all possible combinations of the following descriptions) will be immediately apparent from further disclosure herein.

[0021] The product can be configured as a cleaning agent product. Detergent products can be classified as fabric care products. Fabric care products can be selected from a group consisting of laundry detergents, upholstery cleaners, brighteners, whiteners, stain removers, scent boosters, and combinations thereof. The cleaning product can be dish soap. The cleaning agent product can be an abrasive cleaner. The cleaning agent product can be a plaque removal product.

[0022] A cleaning agent product can be a formulation of multiple components, and multiple hollow core granules can constitute one of the multiple components. The cleaning agent product may be a formulation of multiple components, in which two or more of the multiple components are included as wall-forming materials for multiple hollow core granules. All of the multiple components may be present as wall-forming materials for multiple hollow core granules. The product can be composed of nutritional supplements. The product can be formulated as a laxative. The product can be composed as a deodorizer.

[0023] Multiple hollow core granules can be configured to include at least one wall-forming material selected from the group consisting of sodium bicarbonate, zeolite, activated carbon, bentonite, and combinations thereof. Multiple hollow core granules can be configured to contain either or both an odor neutralizer and / or an odor masking agent. The product can be composed of animal litter. Multiple hollow core granules can be configured to contain sodium bicarbonate as at least one wall-forming material. Multiple hollow core granules can be configured to include clay as at least one wall-forming material. Clay can contain bentonite.

[0024] Multiple hollow core granules may constitute at least 5% by weight of the animal litter. The product can be formulated as a pet litter additive. Pet litter additives can be selected from the group consisting of fillers, flocculants, binders, preservatives, dust removers, fragrances, and mixtures thereof.

[0025] The product can be used as fertilizer. Multiple hollow core granules can be configured to include one or more nitrogen sources, phosphorus sources, potassium sources, and micronutrient sources as at least one wall-forming material. Multiple hollow core granules can be configured to include individual clay particles as at least one wall-forming material. At least one fertilizer material can be absorbed, adsorbed, or otherwise combined with the individual clay particles. Multiple hollow core granules can be configured to contain one or more fertilizer materials in a form encapsulated as at least one wall-forming material.

[0026] The product can be used as a pest control agent. Multiple hollow core granules contain bifenthrin, acephate, carbaryl, cyfluthrin, 2,4-dichlorophenoxyacetic acid, trifluralin, chlorpyrifos, arethrin, cypermethrin, disulfonate, 2,6-dichlorobenzonitrile, metrachlor, cyhalosrin, hydramethylnon, atrazine, chlorothalonil, mycrobutanil, dicamba, azadirachtin, captan, diazinon, carbofuran, methomyl, deltamethrin, propiconazole, borate, dinotefuran, dithiopyr, isoxaben, and prodial. The formulation may include an active agent selected from the group consisting of quinchlorac, cethoxydim, iron(III) phosphate, mancozeb, thiophanate-methyl, esfenvalerate, tebuconazole, resmethrin, glyphosate, malathion, permethrin, imidacloprid, fipronil, abamectin, spinosad, triclopyr, piperonyl butoxide, pendimethalin, oryzalin, oxadiazone, and combinations thereof.

[0027] Multiple hollow core granules can be configured to include individual clay particles as at least one wall-forming material. At least one pest control agent material can be absorbed, adsorbed, or otherwise combined with the individual particles of clay.

[0028] In exemplary embodiments, the present disclosure can further provide methods for preparing hollow core granules. In particular, such methods may include combining a binder having a melting point of about 40°C to about 95°C with a plurality of individual particles of at least one wall-forming material that are substantially insoluble in the binder and have a melting point higher than that of the binder to form a mixture; heating the mixture to a maximum temperature above the melting point of the binder and below the melting point of the plurality of individual particles of the at least one wall-forming material to form aggregates of the plurality of individual particles of the at least one wall-forming material; and cooling the aggregates of the plurality of individual particles of the at least one wall-forming material to form hollow core granules. The production method may be further defined with respect to one or more of the following descriptions, and these descriptions may be combined as desired in any number or order, and the ability to perform any particular combination of the following descriptions (or all possible combinations of the following descriptions) will be immediately apparent from further disclosures herein.

[0029] The formed hollow core granules may include at least one wall that substantially encloses and partitions the hollow core, substantially lacking both solid and liquid, the at least one wall comprising a plurality of individual particles of at least one wall-forming material, the plurality of individual particles being sufficiently cohesive and bonded together such that the at least one wall is structurally self-supporting. Multiple individual particles of the binder and at least one wall-forming material can be combined such that the amount of binder present in at least one wall of the hollow core granules is about 0.1% to about 50% by weight, based on the total weight of the hollow core granules. The amount of binder present in at least one wall of the hollow core granules can be approximately 5% to 30% by weight, based on the total weight of the hollow core granules. This process can be carried out in a fluidized bed. Cooling may include cooling to a temperature below the melting point of the binder.

[0030] This disclosure may further relate, in one or more embodiments, to products comprising one or more hollow core granules prepared according to the methods specifically provided above and / or otherwise described herein. In certain non-limiting exemplary embodiments, the products may be selected from the group consisting of laundry detergents, dish soaps, fabric cleaners, fabric deodorizers, polishing cleaners, plaque removal compositions, disinfectants, stain removers, whiteners, brighteners, bleaches, scent boosters, absorbents, adsorbents, deodorizers, odor masking products, fertilizers, pest control agents, animal litter, and animal litter additives.

[0031] This disclosure further includes a method for delivering one or more materials to a desired site of use, wherein the one or more materials are provided for delivery as a plurality of individual particles of the material contained in at least one wall of a hollow core granule as described herein. [Brief explanation of the drawing]

[0032] [Figure 1] Figure 1 is a partial cross-sectional perspective view of a hollow core granule according to an exemplary embodiment of the present disclosure. [Figure 2] Figure 2 is a partial cross-sectional view of an enlarged portion of the wall of a hollow core granule according to an exemplary embodiment of the present disclosure. [Figure 3] Figure 3 is a partial cross-sectional view of an enlarged portion of the wall of a hollow core granule according to a further exemplary embodiment of the present disclosure. [Figure 4] Figure 4 is a cross-sectional view of a hollow core granule incorporating multiple walls / layers according to an exemplary embodiment of the present disclosure. [Figure 5] Figure 5 is a graph showing the bulk density versus processing time of hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 6] Figure 6 is a graph showing the wall-forming material content versus processing time for hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 7]Figure 7 is a graph showing the fracturing strength versus processing time for hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 8] Figures 8A to 8E are graphs showing the wear of hollow core granules prepared according to exemplary embodiments of this disclosure at different residence times in a fluidized bed apparatus. [Figure 9] Figure 9 is a graph showing the granule size and associated cavity size of hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 10] Figure 10 is a graph showing the fractional weights of hollow core granules prepared according to exemplary embodiments of this disclosure at different residence times in a fluidized bed apparatus. [Figure 11] Figure 11 is a graph showing the granular bulk density for hollow core granules having a PEG binder and bentonite wall-forming material prepared according to exemplary embodiments of this disclosure at different residence times in a fluidized bed apparatus. [Figure 12] Figure 12 is a graph showing the dimensions of hollow core granules and associated cavity dimensions prepared according to exemplary embodiments of this disclosure as a function of processing time in a fluidized bed apparatus. [Figure 13] Figure 13 is a graph showing the percentage of cavity volume relative to the total granule volume of hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 14] Figure 14 is a graph showing the granule size and associated cavity size of hollow core granules prepared according to exemplary embodiments of this disclosure as a function of residence time in a fluidized bed apparatus. [Figure 15] Figure 15 is a graph showing the percentage of cavity volume relative to total granule volume of hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 16] Figure 16 is a graph showing the wear of hollow core granules prepared according to exemplary embodiments of the present disclosure as a function of sieving time. [Figure 17] Figure 17 is a table showing data for various hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 18] Figure 18 is a table showing additional data for various hollow core granules prepared according to exemplary embodiments of the present disclosure. [Figure 19] Figures 19A and 19B are scanning electron microscope (SEM) images at different magnifications of hollow core particles having zeolite as a wall-forming material according to exemplary embodiments of the present disclosure. [Figure 20] Figures 20A and 20B are SEM images at different magnifications of hollow core particles having activated charcoal as a wall-forming material according to exemplary embodiments of the present disclosure. [Figure 21] Figures 21A, 21B, and 21C are SEM images at different magnifications of hollow core particles having sodium bicarbonate as a wall-forming material according to exemplary embodiments of the present disclosure. [Figure 22] Figure 22 is a graph showing the performance of hollow core particles according to exemplary embodiments of this disclosure against sodium bicarbonate alone and bentonite alone for reducing the malodor caused by the release of ammonia from a specific amount of cat litter mimicry composition, felinine, added to a large amount of test material. [Figure 23] Figure 23 is a graph showing the performance of hollow core particles according to exemplary embodiments of this disclosure against sodium bicarbonate alone and bentonite alone for reducing the malodor caused by the release of sulfur compounds from a specific amount of cat litter mimic composition, felinine, added to a large amount of test material. [Figure 24] Figure 24 is an image of hollow core granules formed from sodium bicarbonate as a wall-forming material and PEG as a binder according to an exemplary embodiment of the present disclosure, the granules being cut in half. [Figure 25] Figure 25 is an image of hollow core granules formed from bentonite as a wall-forming material and PEG as a binder according to an exemplary embodiment of the present disclosure, the granules being cut in half. [Figure 26]Figure 26 is a base image of hollow core granules formed from sodium bicarbonate and bentonite as wall-forming materials and PEG as a binder, according to an exemplary embodiment of the present disclosure. [Figure 27] Figure 27 is an image of hollow core granules formed from sodium bicarbonate as a wall-forming material and polyoxyethylene stearyl ether as a binder according to an exemplary embodiment of the present disclosure, the granules being cut in half. [Figure 28] Figure 28 is an image of hollow core granules formed from bentonite as a wall-forming material and polyoxyethylene stearyl ether as a binder according to an exemplary embodiment of the present disclosure, the granules being cut in half. [Modes for carrying out the invention]

[0033] The present invention will be described in more detail below with reference to various embodiments. These embodiments are provided to make this disclosure thorough and complete and to fully convey the scope of the invention to those skilled in the art. In fact, the invention may be embodied in many different forms and should not be construed as being limited to the embodiments described herein, but rather these embodiments are provided so that this disclosure satisfies applicable legal requirements. Where used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural references unless otherwise explicitly indicated in the context.

[0034] This disclosure relates to structures having a substantially hollow core, compositions incorporating such structures, methods for manufacturing such structures, and uses / applications of such structures and compositions. The structures provided herein may, in particular, be hollow core structures comprising at least one shell / wall surrounding a cavity that is a hollow core. The shell / wall may specifically include at least one solid wall-forming material and a binder material. Multiple solid wall-forming materials may be utilized. Similarly, multiple binders may be utilized. At least one solid wall-forming material can be bound together with a binder to constitute a plurality of individual particles that partition the shell / wall surrounding the cavity that partitions the hollow core. The shell / wall may be characterized as a substantially continuous wall surrounding and enclosing the hollow core or cavity. Individual hollow core structures in which the wall is formed from a plurality of individual particles may therefore be referred to as granules. Therefore, as used herein, the term “granules” may refer to a hollow core structure, and the term “particles” may refer to individual pieces of solid material used as wall-forming material to form the shells / walls of the granules or hollow core structure. In some embodiments, there may be multiple shells / walls, each shell / wall independently having a different composition and / or thickness. Furthermore, the hollow core may be configured such that one or more components are contained therein in such quantities that the hollow core is not completely filled and therefore can still be called a hollow core. Such hollow core structures may be useful as standalone materials and / or in the manufacture of various products in which the hollow core structure is mixed with further components or otherwise combined.

[0035] The hollow core granules according to this disclosure can be configured with specific properties and applications. The exact nature of the properties and / or applications may vary based on other factors, including the properties of the material(s) forming the shell(s) / wall(s), the size of the hollow core structure, and the properties of any materials forming the components contained within the hollow core. In some embodiments, the hollow core structure of the present invention can be configured to provide one or more deodorizing functions. This may include exhibiting the ability to absorb and / or entrain odor-causing compounds, and may alternatively or additionally include exhibiting odor neutralizing ability, such as by containing and / or delivering odor neutralizing agents. In some embodiments, the hollow core structure of the present invention can be configured to provide one or more absorption and / or adsorption functions. This may include exhibiting the ability to absorb liquids, which may include polar and / or nonpolar liquids. Furthermore, the hollow core structure can be configured to selectively absorb and / or adsorb in terrestrial and / or underwater fields.

[0036] In some embodiments, the hollow core structure of the present invention can be provided as a designed form of one or more chemical products, compounds, compositions, etc. having a desired application, and improvements in properties can be achieved by providing one or more chemical products, compounds, compositions, etc. in a hollow core format (for example, a hollow core sodium carbonate exhibiting improved odor absorption and / or cleaning properties compared to “ordinary” sodium bicarbonate that is not a redesigned hollow core format, or a hollow core clay exhibiting improved liquid absorption compared to “ordinary” clay that is not a redesigned hollow core format). The improved properties may particularly relate to the natural form of the chemical product, compound, composition, etc., where the natural form is the form in which the chemical substance, compound, or composition exists naturally, or the form in which the chemical substance, compound, or composition is typically manufactured and / or sold. Natural forms can be, in particular, forms that are not hollow core formats.

[0037] The hollow core structure of the present invention may be useful as a standalone chemical or compound that can be made available for a variety of purposes. Similarly, such a standalone chemical or compound may be used as one or more components of a more complex composition (for example, a complex composition which is a material formed from at least two different chemicals, compounds, etc.). Furthermore, two or more chemicals, compounds, etc. may be combined to form hollow core granules, which may form part or all of the composition. In exemplary embodiments, the standalone chemicals, compounds, etc. may include materials such as sodium bicarbonate, clay, and surfactants, and further examples of such materials will be discussed further herein. Thus, such materials can be provided as products in which all or part of them are formed from prepared granules. For example, cleaning products, abrasives, personal care products, deodorizers, animal litter, etc., may be prepared as a whole from the hollow core granules described herein, or such hollow core granules may form one or more components of such products. In some embodiments, the hollow core structure of the present invention can be configured specifically for applications in delivering a desired product to a desired environment. For example, fertilizers, pest control agents, etc., can be provided as hollow core structures that enable the delivery of fertilizers, pest control agents, etc., having improved properties. The aforementioned uses and products are understood to be exemplary embodiments and are not intended to limit the useful applications of the hollow core structures of this disclosure.

[0038] Structure with a hollow core

[0039] Referring to Figure 1, the structure / granule 10 according to this disclosure may include an outer wall 15 surrounding and substantially enclosing an inner core 20, the inner core may be substantially hollow and therefore partition a cavity. The term “wall” should not be interpreted as limiting, and it should be understood that such a term may be synonymous with a similar term, e.g., “shell.” Thus, the term “wall” may be used throughout this disclosure, but it should be understood that the wall encloses a cavity partitioning a hollow core. The substantially hollow core may contain relatively small amounts of material (e.g., solid or liquid), but otherwise is essentially an open void within the outer wall. Specifically, the phrase “substantially hollow” may indicate that at least 90 volume percent, at least 95 volume percent, or at least 99 volume percent of the core does not contain any solid and / or liquid material. The structure 10 may be further defined with respect to having an outer wall surface 17 and an inner wall surface 19. Therefore, the core of the hollow core structure may be defined as the internal volume of the hollow core structure whose boundaries are defined by the inner wall surface 19.

[0040] The hollow core granules according to this disclosure may be described in particular as comprising at least one wall that substantially encloses and partitions a hollow core substantially lacking both solid and liquid, wherein the at least one wall comprises a plurality of individual particles of at least one wall-forming material, the plurality of individual particles being sufficiently cohesive and bonded together such that the at least one wall is structurally self-supporting. The at least one wall substantially enclosing a cavity may indicate that the wall completely encloses the cavity, or that the wall exhibits open porosity in such a way that one or more open pores can partition one or more pathways between the internal cavity and the external environment. In addition to the further considerations provided herein, the property of at least one wall "substantially enclosing" a cavity can mean, in particular, that the wall completely encloses the cavity (i.e., 100% enclosure) or that it encloses the cavity with a small portion of the wall being discontinuous, such as through the presence of open pores or other discontinuities in the wall that provide openings between the cavity and the external environment (i.e., at least 90%, at least 95%, at least 98%, or at least 99% enclosure based on the area of ​​the wall). The determination of the amount of enclosure can be calculated based on measurements of microscopic images. For example, in the SEM images provided in Figures 19A to 21C, it is clear that open pores in the wall can be visually identified and measured. Other analytical methods may be used in the same manner. In some embodiments, it may be desirable to have less than 100% enclosure of the cavity in order to achieve improved properties as described herein. The fact that a cavity is "substantially devoid" of any solid or liquid can indicate that the core of the granule is not intentionally filled with solid or liquid material, and that there is an open space extending across the hollow core granule when measured from the inner surface of the wall. This is particularly evident in the images of hollow core granules cut in half to show the internal cavity, shown in Figures 24, 25, 27, and 28. Thus, substantially devoid can mean that the internal volume of the core, partitioned by the inner surface of the wall, is at least 90%, at least 95%, at least 97%, or at least 99%, open, and that no solid or liquid is present.For multiple individual particles to be "well-bound" can mean that the particles maintain their positions relative to each other and do not exhibit any significant rearrangement during normal handling of the hollow core granules.

[0041] The hollow core structure 10 may be provided in various sizes, and the average size may be defined with respect to the diameter of the hollow core structure (e.g., in the case of a substantially spherical structure) or with respect to the maximum dimension (e.g., a lateral or longitudinal measurement in the case of a substantially elongated or heterogeneous structure). The hollow core granules may have an average size of about 0.1 mm to about 20 mm, about 1 mm to about 10 mm, or about 2 mm to about 5 mm. In some embodiments, the hollow core structure may be substantially smaller in size, such as having an average size of about 0.1 mm to about 7 mm, about 0.5 mm to about 6 mm, about 1 mm to about 5 mm, about 1.5 mm to about 4.5 mm, or about 2 mm to about 4 mm. In other embodiments, the hollow core structure may be substantially larger in size, such as having an average size of about 2 mm to about 20 mm, about 3 mm to about 15 mm, or about 4 mm to about 12 mm. In yet another embodiment, even larger sizes such as approximately 5 mm to approximately 50 mm, approximately 10 mm to approximately 45 mm, or approximately 15 mm to approximately 40 mm can be achieved. Thus, the aforementioned sizes may refer to individual granules. Furthermore, as will become clearer from the manufacturing methods described below, the granule size achieved may be defined at least in part by the particle size of the binder material used. Thus, the binder material may be provided with a larger particle size to achieve larger hollow core granules, or the binder material may be provided with a smaller particle size to achieve smaller hollow core granules.

[0042] In some embodiments, the individual granules of the hollow core structure may be substantially spherical, substantially elliptical, or otherwise substantially rounded. In such embodiments, the walls may completely enclose the cavity that partitions the hollow core (i.e., the hollow core is completely isolated from the surrounding environment). However, other shapes are not excluded. For example, in certain embodiments, the hollow core structure 10 provided herein may be elongated, for example, substantially fibrous or tubular, and may have closed ends, open ends, or partially closed ends. Furthermore, the structure 10 may be substantially irregular in shape. For example, the hollow core granules may have a substantially elliptical shape. Furthermore, at least a portion of the walls of the hollow core granules may be concave. In some embodiments, a plurality of structures 10 may be bonded to each other to form aggregates of two, three, four, or five or more structures. Such aggregates may have a substantially "pear" shape (for example, when the two adhered particles are of different sizes) or a substantially "figure eight" shape (for example, when the two adhered particles are of substantially the same size).

[0043] As illustrated in Figure 1, the walls 15 of the structure 10 are substantially uniform in thickness. However, in some embodiments, the thickness of the walls 15 may vary. The average wall thickness (e.g., measured from the outer wall surface 17 to the inner wall surface 19) may be in the range of about 0.05 mm to about 8 mm, about 0.1 mm to about 7 mm, about 0.5 mm to about 6 mm, about 1.0 mm to about 5 mm, or about 1.5 mm to about 2.5 mm. If small-sized granules are prepared, their average wall thickness may be proportionally smaller, for example, about 0.1 mm to about 4 mm, about 0.25 mm to about 3.5 mm, about 1 mm to about 3 mm, or about 1.5 mm to about 2.5 mm. The wall thickness and overall size of the hollow core structure 10 may vary based on the type of material used to form the hollow core structure. In particular, the properties of the binder used can strongly influence the size of the cavities that partition the core of the hollow core structure. Similarly, the wall thickness may depend at least partially on the size of the individual particles of the wall-forming material used. In some embodiments, processing conditions, such as the length of time spent in the fluidized bed, may also be a factor in the dimensions of the hollow core structure. Thus, the relative dimensions of the overall size of the hollow core structure, the wall thickness of the hollow core structure, and the size of the cavities that partition the hollow core of the structure may be customized through the selection of binder material, the type of wall-forming material, and the size of the individual particles of the wall-forming material. In some embodiments, such dimensions can be summarized in terms of the relationship between the diameter of the cavities that partition the hollow core of the individual granules (i.e., the diameter across the hollow core at its maximum dimension when measured on the inner wall surface) and the total diameter of the individual granules (i.e., the diameter across the granules at its maximum dimension when measured on the outer wall surface). In particular, the cavity diameter can be about 10% to about 80%, about 15% to about 65%, about 20% to about 60%, about 25% to about 55%, or about 30% to about 50% of the granule diameter. In some embodiments, the relative dimensions can be summarized in terms of the volume of the cavity partitioning the hollow core relative to the total volume of the granules. In particular, the volume of the cavity can be about 0.1% to about 50%, about 0.25% to about 25%, about 0.5% to about 10%, about 0.7% to about 7%, or about 1% to about 4% of the total volume of the granules.The relative dimensions mentioned above may also affect the bulk density of the hollow core structure. In various embodiments, the hollow core structures described herein may have bulk densities in the ranges of about 200 g / liter (g / L) to about 2000 g / L, about 250 g / L to about 1200 g / L, about 200 g / L to about 900 g / L, about 400 g / L to about 850 g / L, about 450 g / L to about 800 g / L, or about 500 g / L to about 750 g / L. Thus, the hollow core granules described herein may have bulk densities that differ significantly from the bulk density of the wall-forming material itself. For example, if sodium bicarbonate has a bulk density of about 1100 g / L, the hollow core granules described herein using sodium bicarbonate as the wall-forming material may have a bulk density of about 700 g / L. Similarly, if bentonite has a bulk density of about 1000 g / L, the hollow core granules described herein using bentonite as a wall-forming material may have a bulk density of about 600 g / L. Thus, in some embodiments, the hollow core granules of the present disclosure may have a bulk density at least 20%, at least 30%, or at least 40% lower than the bulk density of the wall-forming material in its natural form (i.e., naturally occurring or commercially available). Specifically, the hollow core granules may have a bulk density at least 10% to about 75%, at least 15% to about 50%, or at least 20% to about 45% lower than the bulk density of the wall-forming material in its natural form. The comparison may be characterized as the density of the formed hollow core granules versus the density of the wall-forming material before it is incorporated into the hollow core granules.

[0044] The hollow core structure of the present invention can still maintain a substantially consistent shape despite having an open or substantially open cavity bounded by walls. This is a remarkable effect, as at least one of the walls is formed from a plurality of individual particles of wall-forming material without an internal mass supporting the wall. Thus, at least one wall can be characterized as substantially self-supporting in that the wall does not substantially collapse itself, but rather maintains the granular shape described above, while having a central cavity substantially lacking any solid or liquid material within it, in some embodiments.

[0045] Hollow core granules can still exhibit remarkably high strength despite being hollow rather than solid throughout the granule. The strength may be, in particular, the fracturing strength, as discussed in the attached examples. This strength may vary depending on the choice of wall-forming material and binder. In some embodiments, the granule strength is at least The granular intensity can be 0.5 Newtons (N), at least 2N, at least 3N, at least 5N, at least 10N, or at least 15N. In some embodiments, the maximum granular intensity may have a maximum value of about 50N. In certain embodiments, the granular intensity can be about 0.5N to about 50N, about 1N to about 30N, about 2N to about 25N, or about 3N to about 20N.

[0046] The walls 15 of the hollow core structure 10 are composed of aggregates of individual particles 152 of one or more solid wall-forming materials, so that the walls 15 have interstitial spaces 154 between the particles 152. This can be seen in the partial cross-sectional view illustrated in Figure 2. Thus, the walls 15 are substantially continuous in that they are formed from individual particles that have sufficiently associated with each other to form a stable, self-supporting structure, and the interstitial spaces can provide specific properties to the hollow core structure 10. As can be seen in Figure 2, the external surface 17 and / or internal surface 19 of the walls 15 are not necessarily uniform and may exhibit a level of roughness or unevenness that can be distinguished from a substantially smooth wall surface. In some embodiments, the interstitial spaces 154 may be at least partially filled with binder material. This is shown in Figure 3, where the particles 152 are substantially surrounded by the binder 155. However, it is understood that the binder 155 does not necessarily have to completely surround all of the particles 152. Similarly, the binder 155 may exist in a discontinuous form, for example, a granular form, so that individual binder particles can bind together two or more particles 152 of the wall-forming material.

[0047] The hollow core structure 10 according to this disclosure may include a single wall 15. However, in some embodiments, the structure 10 may comprise a plurality of walls, which in some embodiments may be characterized as walls having a multilayer structure. As can be seen in the cross-sectional view of Figure 4, the structure 10 may comprise an internal core or cavity 20 that may be substantially empty or lack solid or liquid material, and a surrounding wall 15. The wall 15 (which may be referred to as the first wall, first layer, inner wall, or inner layer) may then be substantially surrounded by another wall 25 (which may be referred to as the second wall, second layer, further wall, further layer, outer wall, or outer layer). Thus, the hollow core structure 10 may comprise a single wall or layer surrounding a substantially hollow internal core 20, or it may comprise a plurality of walls or layers. If a plurality of walls or layers are present, each individual wall or layer may have a different average thickness, or the relative average thickness of the walls or layers may vary. In some embodiments, the outer wall or outer layer may have an average thickness thinner than the inner wall or inner layer. At least one of the multiple walls or layers is an aggregate of individual particles of the wall-forming material. However, one or more walls or layers, particularly the outer wall or outer layer, may constitute a coating applied to the inner wall or inner layer. Aggregation may be referred to in more detail with respect to the substantial adhesion of individual particles of the wall-forming material to adjacent particles. Adhesion may occur by various interaction forces and may be achieved at least partially by the presence of one or more binder materials that at least partially coat the individual particles of the wall-forming material and / or at least partially fill the interstitial spaces between the individual particles of the wall-forming material.

[0048] In some embodiments, the hollow core structures described herein may be defined with respect to the porosity of the walls of the structure. Porosity may be defined at least in part with respect to the presence of interstitial spaces 154 between the particles 152 that form the walls 15 of the individual granules of the hollow core structure 10. Porosity may be controlled in various ways, for example, by controlling the amount of any binder that may be present by combining particles of two or more different average particle sizes, by changing the average size of the individual particles 152 that form the walls 10. For example, the particles used as the wall-forming material may have an average size in the range of about 0.01 mm to about 2 mm, about 0.02 mm to about 1.5 mm, about 0.05 mm to about 1.0 mm, or about 0.1 mm to about 0.8 mm. In some embodiments, a range of particle sizes may be used to achieve a higher packing density of the walls by using smaller particles to fill the spaces between larger particles. Therefore, the wall-forming material particles may have an average size that spans a range such that the minimum particle size differs from the maximum particle size by about 1 mm, about 0.8 mm, about 0.5 mm, or about 0.2 mm.

[0049] In some embodiments, porosity may be further controlled, at least partially, through the selection of materials used to form the walls, for example, by utilizing highly porous or low-porosity materials, or by utilizing a combination of materials with different porosity. Examples of materials useful for forming the walls of the hollow core structure of the present invention are discussed in detail below. In some embodiments, porosity may be defined with respect to one or more of the following: average pore size, pore distribution, etc. For example, the average pore diameter of the pores in the walls of the structure may be in the range of about 100 nm to about 200 μm, about 250 nm to about 100 μm, or about 500 nm to about 50 μm.

[0050] In addition to the properties of the walls, the hollow core structures according to this disclosure can also be defined with respect to the properties of the hollow core. As described above, the cavity (i.e., open volume) that partitions the hollow core may vary, and the cavity may be substantially devoid of any solid or liquid material (e.g., less than 10%, less than 5%, less than 2%, or less than 1% of the cavity volume, containing any solid or liquid therein at the time of manufacture). In some embodiments, the hollow core structure may include contents of further material present in the volume partitioned by the inner surface of the innermost wall of the hollow core structure. For example, a structural scaffold may be present in the cavity partitioning the hollow core. In another example, a liquid may be filled in the cavity partitioning the hollow core. Thus, the hollow core structure can provide a delivery article in which the material present in the hollow core can be delivered in a controlled manner via dissolution, destruction, or other removal of the outer wall to release the internal material.

[0051] The structures described herein can be characterized using various inspection techniques. For example, scanning electron microscopy (SEM) testing may be useful for characterizing particle properties, particle morphology, porosity, and pore distribution. Therefore, the structures and products incorporating such structures can be further defined with respect to one or more of the aforementioned features. The porosity of hollow core granules can be seen, for example, in the scanning electron microscopy (SEM) images shown in Figures 19A to 21C. Hollow core granules containing zeolite particles as wall-forming material are shown in the SEM image of Figure 19A at 59x magnification and in the SEM image of Figure 19B at 270x magnification. Hollow core granules containing activated charcoal particles as wall-forming material are shown in the SEM image of Figure 20A at 68x magnification and in the SEM image of Figure 20B at 229x magnification. Hollow core granules containing sodium bicarbonate particles as the wall-forming material are shown in the SEM images at 87x magnification in Figure 21A, at 346x magnification in Figure 21B, and at 1,535x magnification in Figure 21C. As can be seen in each image, the hollow core granules were consistently prepared using particles of different wall-forming materials. Furthermore, it is clear from the images that the hollow core granules consistently maintain a similar structure, and that the walls of the hollow core granules have numerous pores between the individual particles of the wall-forming material. It can be seen that the open porosity varies depending on whether there are many or few pores filled with the binder material. Therefore, the hollow core granules can be configured with higher or lower open porosity by controlling the processing so that more or less binder is retained in the walls of the hollow core granules. The ability to control open porosity can be very useful in fine-tuning the properties achieved, such as improved dissolution, absorption / adsorption properties, and other properties that will be further discussed herein.

[0052] Various wall-forming materials may be used to prepare one or more walls of the hollow core granules according to this disclosure. The wall-forming materials may be functional, structural, or both. Functional wall-forming materials can be any material contained in the hollow core granules that imparts a desired function to the product containing the hollow core granules. Thus, such materials may be used individually to form a product exhibiting the function of the functional material, and / or any number of such materials may be used in any combination to form a product exhibiting a combined function. It is understood that a product containing hollow core granules having one or more functional materials as wall-forming materials may also contain other non-functional components, such as fillers, extenders, inert components, etc. Furthermore, the hollow core granules themselves may contain fillers, extenders, inert components, etc., as one or more wall-forming materials in combination with one or more functional materials to achieve an appropriate dosage of the functional material in the hollow core granules as a whole. Functional materials(s) may be available in solid form (e.g., particles) under the conditions necessary for the preparation of the hollow core granules described herein. In such cases, the functional materials may be even more effective as structural components of the walls of the hollow core granules. However, in some embodiments, one or more functional materials for use in the hollow core granules may typically be available in liquid form under the conditions necessary for the preparation of the hollow core granules described herein. In such embodiments, the liquid materials may be combined with the structural materials to provide the liquid in solid form. The structural materials, which may be combined with one or more liquid materials, may also be functional materials. However, the structural materials, which may be combined with one or more liquid materials, may be non-functional in the hollow core granules being prepared, and therefore the structural materials may be referred to as carrier components or particles, fillers, extenders, inert components or particles, etc. Clay, ceramics, silicates, zeolites, carbon, and even other minerals or salts may be useful as carriers that can absorb, adsorb, or impregnate the desired liquid to be included in the hollow core granules.The carrier particles may be considered substantially inert to the delivery site (i.e., they do not provide the desired benefit but are still safe to use), may remain after the delivery of the activator, or may further dissolve or disintegrate. In some embodiments, the carrier particles may have an additive effect such that the effectiveness of the liquid functional material is improved through its combination with the carrier particles, or the carrier particles themselves produce different desired effects at the delivery site.

[0053] The liquid component may, alternatively or additionally, be provided in a form suitable for use in forming one or more walls of hollow core granules as described herein, by the use of encapsulation technology. Therefore, capsules and / or microcapsules may be utilized. The encapsulation technology may also be used in conjunction with other solid materials to provide the encapsulated component in a controlled release form, thereby requiring the encapsulation shell to be solubilized, decomposed, or otherwise removed so that the encapsulated material is released at the delivery site.

[0054] Encapsulation of any material used as a wall-forming material for the hollow core granules of the present invention can be carried out using any suitable method. For example, microcapsules can be formed using any of the following chemical encapsulation techniques, e.g., solvent evaporation, solvent extraction, organic phase separation, interfacial polymerization, simple and complex coacervation, in situ polymerization, liposome encapsulation, and nanoencapsulation. Alternatively, physical methods of encapsulation can be used, e.g., spray coating, pan coating, fluidized bed coating, annular jet coating, spinning disc spraying, spray cooling, spray drying, spray chilling, fixed nozzle co-extrusion, centrifugal head co-extrusion, or immersion nozzle co-extrusion. Regardless of the encapsulation methodology employed, the material used to form the capsule may vary. Classes of materials typically used as wall or shell materials include proteins, polysaccharides, starches, waxes, fats, natural and synthetic polymers, and resins. Examples of materials for use in the microencapsulation process used to form microcapsules include gelatin, gum arabic, polyvinyl acetate, potassium alginate, carob bean gum, potassium citrate, carrageenan, potassium polymetaphosphate, citric acid, potassium tripolyphosphate, dextrin, polyvinyl alcohol, povidone, dimethylpolysiloxane, dimethyl silicone, purified paraffin wax, ethylcellulose, bleached shellac, processed food starch, sodium alginate, guar gum, sodium, sodium citrate, carboxymethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, sodium ferrocyanide, sodium polyphosphate, locust bean gum, methylcellulose, sodium trimetaphosphate, methylethylcellulose, sodium tripolyphosphate, microcrystalline wax, tannic acid, petroleum wax, terpene resins, tragacanth, polyethylene, xanthan gum, and polyethylene glycol.Microcapsules are commercially available, and exemplary types of microcapsule technology are found in: Gutcho, Microcapsules and Microencapsulation Techniques (1976); Gutcho, Microcapsules and Other Capsules Advances Since 1975 (1979); Kondo, Microcapsule Processing and Technology (1979); Iwamoto et al., AAPS Pharm. Sci. Tech. 2002 3(3): article 25; of the type described in U.S. Patent No. 5,004,595 by Cherukuri et al.; U.S. Patent No. 5,690,990 by Bonner; U.S. Patent No. 5,759,599 by Wampler et al.; U.S. Patent No. 6,039,901 by Soper et al.; U.S. Patent No. 6,045,835 by Soper et al.; U.S. Patent No. 6,056,992 by Lew; U.S. Patent No. 6,106,875 by Soper et al.; U.S. Patent No. 6,117,455 by Takada et al.; U.S. Patent No. 6,482,433 by DeRoos et al.; and U.S. Patent No. 6,929,814 by Bouwmeesters et al., each of which is incorporated herein by reference.

[0055] Non-limiting exemplary embodiments of materials that may be suitable for use in forming the walls of hollow core structures described herein include: clay (e.g., bentonite), glass, ceramics, alumina, silicates, zeolites, carbon (e.g., activated charcoal), metals, salts (e.g., sodium bicarbonate or baking soda, sodium carbonate or soda ash, sodium chloride, etc.), powder formulations (e.g., solid cleaning compositions, e.g., laundry detergents, dish soaps, fabric cleaners / deodorizers, abrasive cleaners, etc.), absorbents, adsorbents, and deodorizers. Examples include deodorants, health or beauty agents, surfactants, enzymes, bleaches, oxidizing agents (e.g., peroxides), reducing agents, gelling agents (e.g., gelatin, pectin, cellulose-based, etc.), flavorings, fragrances, abrasives, fertilizers, insecticides, pest control agents, fungicides, herbicides, antimicrobial agents, anti-sticking agents, fillers, binders, preservatives, fluorescent agents (e.g., brighteners), disinfectants, chelating agents, molecular binders, dyes, colorants, colored particles, dust removers, and other materials known for use in consumer products and / or industrial settings to provide specific functions to products. Any of the foregoing may be functional materials as referenced above, and may also be provided as standalone products that can be added to other products to impart a desired function and / or combined with other products as necessary to achieve additive results. Such materials may be used in solid form as functional and / or structural wall-forming materials, with or without modification, to impart controlled release and / or modify the hydrophilic / hydrophobic properties of the material. Such materials may be used in liquid form as functional wall-forming materials when combined with a carrier or other solid material and / or modified to a solid format, e.g., the encapsulation method described above. The foregoing list of wall-forming materials is not intended to be exhaustive, and it will be understood that those skilled in the art can identify, in light of the entirety of this disclosure, other chemical products, compounds, compositions, etc., used in or as commercial products that can be similarly utilized in forming the hollow core structures of the disclosure.

[0056] In certain embodiments, bentonite or sodium bicarbonate may be used specifically as wall-forming materials for a vast number of applications of such materials, and both may be used as functional and / or structural components of the hollow core granules of the present invention. Non-limiting examples of bentonite clays that can be used include sodium bentonite, potassium bentonite, lithium bentonite, calcium bentonite, and magnesium bentonite, or combinations thereof. Clay-based liquid absorbent materials are described, for example, in U.S. Patent No. 8,720,375 by Miller et al., the disclosure of which is incorporated herein by reference. Furthermore, non-limiting examples of absorbent or adsorbent materials suitable for use in hollow core granules in combination with bentonite or as a substitute for bentonite include clay, quartz, feldspar, calcite, illite, calcium carbonate, carbon, mica, Georgian white clay, hectorite, smectite, opal, kaolinite, pumice, tobermite, slate, gypsum, vermiculite, halloysite, sepiolite, marl, diatomaceous earth, dolomite, attapulgite, montmorillonite, Monterey shale, Fuller's soil, silica, fossilized plant materials, perlite, expanded perlite, mixtures thereof, and similar materials.

[0057] Preferably, the wall-forming material during the preparation of hollow core granules is in a substantially particulate solid form and may be adapted or configured to be substantially insoluble in the binder that may be used to form the wall structure. This may refer to the spontaneous state of the material or may result from a combination of the desired material and another structural material, as already discussed above. In some embodiments, the wall-forming material, when used in the preparation of hollow core granules, is composed of solid particles having a melting point of about 100°C or higher, about 110°C or higher, about 120°C or higher, or about 130°C or higher.

[0058] Any functional material in hollow core granules according to this disclosure may be provided in a manner that provides controlled release of the material. Controlled release can specifically represent any of the following: delayed release in which substantially the entire amount of material (i.e., a “bolus”) is released after a predetermined period; delayed release in which the release of the material begins after a predetermined period and proceeds over a second predetermined period (i.e., a “long-term release”); or metric release in which the release of the material begins substantially immediately after application but proceeds over a predetermined period. Controlled release can be achieved by using the encapsulation methods considered above. Controlled release can also be achieved by selecting materials configured as “rapid-release” and “sustained-release” forms of the material. Furthermore, configurations of controlled release can be applied to any material, in conjunction with any product, and / or in conjunction with any use of hollow core granules, as otherwise described herein. While specific products discussed herein may be specifically described in terms of their controlled release forms, it is understood that these controlled release characteristics can be applied to any product described herein, regardless of whether such characteristics are specifically referred to in relation to other considerations of the product herein.

[0059] In some embodiments, the walls of the hollow core structures described herein may be formed from a gelling material. Such a gelling material may comprise at least one hydrophilic long-chain polymer and at least one water source. Useful hydrophilic long-chain polymers in this specification include long-chain carbohydrates (e.g., polysaccharides) and various proteins. The hydrophilic long-chain polymer is preferably configured to thicken upon hydration (with or without heating) to form a gel. Non-limiting examples of hydrophilic long-chain polymers that may be used to form walls according to this disclosure include gelatin, pectin, carrageenan, gellan gum, guar gum, locust bean gum, gum arabic, xanthan gum, starch, methylcellulose, agar, konjac, alginates, and combinations thereof (including single-component, two-component, three-component, or four-component blends). The hydrophilic long-chain polymer may contain about 0.1% to about 20% by weight, about 1% to about 15% by weight, or about 2% to about 10% by weight of the gelling material used to form the walls of the hollow core structure. The gelling material may otherwise contain about 80% to about 99.9% by weight, about 85% to about 99% by weight, or about 90% to about 98% by weight of a water source, particularly deionized water.

[0060] In some embodiments, the walls of the hollow core granules may contain lipid materials. Non-limiting examples of lipid bases include oils, fats, and compositions formed using them. In some embodiments, edible fats may be used in particular. Suitable lipid materials for use in forming lipophilic compositions include fats and oils derived from one or more sources, such as plant sources, animal sources, nut sources, and seed sources. Suitable lipid materials may be predominantly or completely saturated, predominantly or completely unsaturated, or hydrogenated. Non-limiting examples of suitable lipid materials include fats and / or oils derived from one or more of the following: cocoa, palm, coconut, almond, cashew, hazelnut, macadamia nut, peanut, pecan, pistachio, walnut, pumpkin seed, sesame seed, soybean, rapeseed, corn, safflower seed, etc. Specific, non-limiting examples of lipid-based materials that may be used in preparing the compositions described herein include chocolate of any cocoa concentration (e.g., milk chocolate, dark chocolate, white chocolate), palm fat, coconut fat, peanut butter, hazelnut fat, vegetable oil, milk fat, confectionery fat (e.g., available from AAK, AB), etc. Such materials may also contain additional components, such as sugars, salts, other oils, etc. For example, chocolate may contain sugars, cocoa butter, alkali-processed cocoa, milk fat, lactose (e.g., derived from milk), soy lecithin, emulsifiers, vanillin, artificial flavors, milk, and / or other components. Milk components that may be used in lipophilic compositions include fats, proteins, and / or sugars derived from cow's milk, goat's milk, etc.

[0061] As described above, in one or more embodiments, the walls of hollow core granules are prepared by the use of a binder, and the formed walls hold the contents of the binder material. However, in some embodiments, substantially all of the binder may be removed from the structure during the processing of the structure. This may occur in particular when one or more wall-forming materials, as described above, are of a nature that allows their particles to remain bound together even after the removal of the binder material. In certain embodiments, at least a portion of the binder is retained in the walls of the formed hollow core granules. For example, the formed granules may contain binder retained in the walls of the granules (e.g., in at least a portion of the interstitial space between individual particles of the wall-forming material) in amounts of about 0.1% to about 50% by weight, about 1% to about 45% by weight, about 2% to about 40% by weight, or about 5% to about 30% by weight, based on the total weight of the granules. The remaining weight of the granules may be comprised of the wall-forming material(s) alone or in combination with any coating applied to the granules.

[0062] The binder material may be provided in a specific format, particularly for use in processing treatments for forming hollow core granules. Specifically, it may be beneficial for the binder to be in granular form when added to a processing apparatus. In this way, the wall-forming material particles can aggregate or accumulate around the binder particles as the solid binder softens by heating. Subsequently, as the binder liquefies, the liquid binder flows out from the core of the granules being formed and into the walls formed by the wall-forming material. For this purpose, it may be particularly useful for the binder particles, seeds, or crystals to have an initial size in the range of about 0.1 mm to about 5 mm, about 0.5 mm to about 4 mm, or about 0.8 mm to about 3 mm.

[0063] Various materials may be used as binders. In some embodiments, the binder may be a material that is substantially solid at temperatures below about 50°C, below about 45°C, or below about 40°C, and liquid above such temperatures. In certain embodiments, the binder may be adapted or configured to be solid at temperatures in the range of about 10°C to about 50°C, about 15°C to about 45°C, or about 20°C to about 40°C. Additionally or alternatively, the binder may be a material having a melting point in the range of about 40°C to about 95°C, about 45°C to about 90°C, or about 50°C to about 90°C. The binder may also be selected for a given application based on whether the binder is hydrophilic or hydrophobic, as further described herein. For example, in some embodiments, hydrophobic binders such as paraffinic hydrocarbons, olefinic hydrocarbons, waxes, beeswax, or similar materials exhibiting the aforementioned state-change properties may be used. Hydrophobic polymers may be used similarly. Non-limiting examples of suitable hydrophobic binders include waxes, paraffins, polycaprolactones, ethylene-vinyl acetate copolymers, polypropylene carbonates, poly(tetramethylene oxide), poly(ethylene adipate), poly(trans-butadiene), thermoplastic polyurethanes (e.g., carbothane TPU), and stearic acid. Similarly, one or more of the above lipid materials may be used as hydrophobic binders. In further embodiments, the binder may specifically be a hydrophilic material, such as polyethylene glycol (PEG). Further examples of suitable binders include materials such as polyoxyethylene fatty ethers derived from various types of alcohols (e.g., lauryl, cetyl, stearyl, and oleyl alcohols), such as Brij® S100 (polyoxyethylene stearyl ether) or Steareth-100. Such polyoxyethylene fatty ethers are inherently more hydrophobic than other hydrophilic binders, such as PEG materials, but may still be useful as hydrophilic binders.Similarly, fatty acids with carbon chain lengths in the range of C10 to C30 may be useful as binders, and one exemplary embodiment is stearic acid. In one or more embodiments, the binder may be a material having a melting temperature lower than the melting temperature of the material used to form the walls of the hollow core structure. Thus, suitable binder materials may have substantially high melting temperatures, for example, in the range of about 90°C to about 200°C, about 100°C to about 180°C, or about 110°C to about 160°C. For example, in some embodiments, plastics (e.g., polyvinyl chloride (PVC), high-density polyethylene (HDPE), etc.), thermoplastics, rubber, and similar materials may be used as binders.

[0064] In some embodiments, the binder may be selected particularly with respect to the viscosity of the binder in liquefied form. Binders with lower liquid viscosity can be processed more quickly for granule formation, while binders with higher liquid viscosity require a longer processing time for granule formation. However, similarly, the liquid viscosity of the binder can affect one or more properties of the finished granules. For example, binders with higher liquid viscosity can result in relatively strong granules. Thus, the selection of the binder can be a factor in the liquid viscosity of the binder. In some embodiments, the flow properties of the binder in liquid form may be controlled at least in part by the selection of the molecular weight of the binder. For example, PEG materials may be particularly useful as binders, and various grades of PEG materials can be selected at least in part based on the molecular weight of the material. In various embodiments, PEG materials suitable for use as binders in hollow core granules may have molecular weights of at least 400 Da, at least 1000 Da, at least 2000 Da, or at least 4000 Da. The maximum molecular weight can be, for example, 50,000 Da or less, 45,000 Da or less, or 40,000 Da or less. More specifically, the PEG molecular weight can be in the range of about 400 Da to about 34,000 Da. In certain embodiments, lower ranges may be used, for example, about 400 Da to about 15,000 Da, about 500 Da to about 12,000 Da, or about 1,000 Da to about 10,000 Da. In other embodiments, higher ranges may be used, for example, about 8,000 Da to about 34,000 Da, about 10,000 Da to about 30,000 Da, or about 12,000 Da to about 25,000 Da.

[0065] Molecular weight can be expressed as weight-average molecular weight (Mw) or number-average molecular weight (Mn). Both expressions are based on characterizing polymer solute-containing solutions as having an average number of molecules (ni) and a molar mass (Mi) of each molecule. Therefore, the number-average molecular weight is defined by the following formula 1.

[0066]

number

[0067] The weight-average molecular weight (also known as the molecular weight average) can be measured directly using light scattering and is defined by the following equation 2.

[0068]

number

[0069] Molecular weight can also be expressed as Z-average molar weight (Mz), and calculations give more weight to molecules with larger molar weights. Z-average molar weight is defined by equation 3 below.

[0070]

number

[0071] Unless otherwise specified, molecular weight (MW) is expressed herein as weight-average molecular weight.

[0072] While various solid wall-forming materials are described above along with various binders, it is understood that this disclosure intends to cover all combinations of wall-forming materials and binders, as described herein and as otherwise deemed useful in light of this disclosure.Thus, the present disclosure includes a hollow core structure in which at least one wall or layer comprises any of the following: particles of one or more types of clay (e.g., bentonite) combined with at least one binder; glass particles combined with at least one binder; one or more ceramic particles combined with at least one binder; one or more alumina particles combined with at least one binder; one or more silicate particles combined with at least one binder; one or more zeolite particles combined with at least one binder; carbon particles combined with at least one binder; one or more metal particles combined with at least one binder; one or more salt particles (e.g., sodium bicarbonate or baking soda, sodium carbonate or soda ash, or sodium chloride) combined with at least one binder; at least one Particles of one or more cleaning compositions combined with one binder; particles of one or more fertilizers combined with at least one of the above binders; particles of one or more pest control agents combined with at least one of the above binders; particles of one or more absorbents and / or adsorbents combined with at least one of the above binders; particles of one or more deodorizers and / or odor inhibitors combined with at least one of the above binders; particles of one or more bleaches or bleaching agents combined with at least one of the above binders; particles of one or more oxidizing agents combined with at least one of the above binders; particles of one or more reducing agents combined with at least one of the above binders; particles of one or more gelling agents combined with at least one of the above binders; particles of one or more fillers combined with at least one of the above binders; and particles of one or more chelating agents combined with at least one of the above binders. Naturally, it is understood that any type of material described herein may be used alone or in combination with a solid when the desired material is not in solid form as a wall-forming material.

[0073] As will be further discussed herein, the selection of wall-forming material and / or binder material can be effective in customizing hollow core granules to exhibit various properties. In some embodiments, hollow core granules can be defined with respect to water absorption capacity. This can be a characteristic feature in particular with respect to hollow core granules containing a wall-forming material and / or binder suitable for the hollow core granules to be hydrophilic. In exemplary embodiments, hollow core granules may have water absorption capacity such that the hollow core granules absorb water by weight of about 5% to about 80%, about 10% to about 70%, or about 15% to about 60% of the initial weight of the hollow core granules. Hollow core granules may also exhibit a higher water absorption rate than the wall-forming material alone. For example, hollow core granules may have a water absorption rate that exceeds the water absorption rate of the wall-forming material used to form the hollow core granules by about 2% to about 20%, about 2% to about 15%, or about 3% to about 10% compared to the wall-forming material in its natural form before being incorporated into the hollow core granules.

[0074] In some embodiments, the hollow core granules described herein may be defined with respect to oil absorption capacity. This can be a characteristic property in particular with respect to hollow core granules comprising a suitable wall-forming material and / or binder such that the hollow core granules are hydrophobic. In exemplary embodiments, hollow core granules may have oil absorption capacity such that the hollow core granules absorb oil by a weight of about 5% to about 80%, about 10% to about 70%, or about 25% to about 65% of the initial weight of the hollow core granules. Hollow core granules may also exhibit a higher oil absorption rate than the wall-forming material alone. For example, hollow core granules may have an oil absorption rate that exceeds the oil absorption rate of the wall-forming material used in forming the hollow core granules by about 5% to about 50%, about 10% to about 40%, or about 15% to about 35% of the oil absorption rate of the wall-forming material used in forming the hollow core granules (i.e., when the wall-forming material is in its natural form before being incorporated into the hollow core granules).

[0075] Preparation method

[0076] The hollow core structures according to this disclosure may be prepared according to a variety of methods. In one or more embodiments, a method for preparing a structure having a substantially hollow core may include combining a binder described herein with a plurality of solid particles of a wall-forming material described herein to form a mixture. The wall-forming material may, in particular, be a material that is substantially insoluble in the binder and has a melting point higher than the melting point of the binder. In light of the exemplary embodiments of the solid wall-forming material and the exemplary embodiments of the binder provided above, it will be immediately apparent which types of solid wall-forming material may be combined with which types of binder to carry out such a method. In exemplary embodiments, the preferred binder may be a material having a melting point of about 40°C to about 95°C (or a further range above), and the preferred solid particles may be a material having a melting point of about 60°C or higher, about 70°C or higher, about 80°C or higher, about 100°C or higher, or about 110°C or higher. Naturally, it is understood that a suitable binder may be selected such that the binder has a melting point at least 5°C, at least 10°C, at least 15°C, or at least 20°C lower than the melting point of the wall-forming material. The binder and solid particles may be combined at a temperature lower than the melting point of the binder, for example, room temperature or ambient temperature. The binder and solid particles may be mixed at this temperature for a specific time, for example, about 15 seconds to about 180 seconds, about 30 seconds to about 150 seconds, or about 45 seconds to about 120 seconds, etc., to provide a substantially homogeneous mixture.

[0077] The combination of materials may be in the first container for transfer to a second container for heating. Alternatively, this process can be carried out in a single unit, such as a fluidized bed reactor. In this way, a fluidizing gas, such as air, flows upward through the bed to bring about mixing and, optionally, heating and / or cooling of the mixture. Other types of reactors may also be used. When using a fluidized bed reactor, the binder material particles may be added to the fluidized bed first, followed by the wall-forming material particles.

[0078] The binder can be melted by heating a mixture of the binder and solid particles to a maximum temperature. Thus, the maximum temperature can be above the melting point of the binder and below the melting points of the multiple solid particles. Such heating can be adapted or configured to form aggregates of the solid particles. In some embodiments, the maximum temperature may be only about 5°C, about 10°C, or about 20°C above the melting point of the binder. The binder may, alternatively or additionally, be at least partially fluidized (e.g., melted) when added to the wall-forming material. For example, the binder in liquid form may be sprayed onto the wall-forming material particles by an atomizer or similar unit adapted or configured to provide the liquid binder in a substantially fine spray or mist form. In some embodiments, in-situ melting can be utilized when binder particles substantially larger than the wall-forming material particles are used. Specifically, hollow core particles may be formed by the penetration of wall-forming material particles into molten binder particles and subsequent layering. However, preferably, the material is supplied in a suitable configuration such that wall-forming material particles accumulate or aggregate around the binder seed particles or crystals, and as heating continues, the binder flows out from the center of the forming granules and enters the interstitial space of the wall-forming particles.

[0079] In some embodiments, heating can be carried out using a specified heating rate. For example, heating may preferably be carried out at a rate of about 5°C / min to about 25°C / min, about 7°C / min to about 22°C / min, or about 10°C / min to about 20°C / min. Heating may start at ambient temperature and continue at the aforementioned rates until the maximum temperature is reached. In some embodiments, the maximum temperature may be maintained over a predetermined period of time. For example, the maximum temperature may be maintained over a period of about 30 seconds to about 1 hour, about 30 seconds to about 45 minutes, or about 2 minutes to about 30 minutes. As can be seen in the attached examples, the residence time at the maximum heating temperature may affect the final granule properties, including wall thickness, granule size, and the percentage of binder present in the walls of the formed granules.

[0080] In some embodiments, the processing time in the fluidized bed reactor can be controlled to adjust the average size of the individual granules of the hollow core structure being prepared. The processing time may also be adjusted to control other properties, such as the size of the cavities in the individual granules of the hollow core structure, the ratio of the cavity diameter to the overall diameter of the granules, and the bulk density of the granules. In some embodiments, the processing time in the fluidized bed reactor can be adjusted to a range of about 10 to about 20 minutes or about 12 to about 18 minutes in order to maximize one or more of the mentioned properties. Lower values ​​can be obtained by utilizing shorter processing times (e.g., about 1 to about 9 minutes or about 3 to about 7 minutes) and / or longer processing times (e.g., about 22 to about 30 minutes). The processing time may also be adjusted based on the viscosity of the liquefied binder. Specifically, higher viscosity may require longer residence times, while lower viscosity may require shorter residence times.

[0081] The aggregate of multiple solid particles formed can be cooled to provide multiple granules, each having a substantially hollow core (i.e., internal cavity). In particular, this may include cooling to a temperature below the melting point of the binder. In some embodiments, it may be beneficial to bring the solid particles to a substantially rapid cooling, e.g., cooling to below the melting point of the binder within a time of about 5 seconds to about 5 minutes, about 10 seconds to about 3 minutes, or about 15 seconds to about 2 minutes. In other embodiments, longer cooling times may be utilized, e.g., about 5 minutes to about 60 minutes, about 10 minutes to about 50 minutes, about 20 minutes to about 40 minutes, or about 25 minutes to about 35 minutes.

[0082] As a non-limiting example, in some embodiments, the preparation of the structures described herein may be carried out in a multi-stage mixer. For example, in a first-stage mixer, wall-forming material particles can be combined with a binder to effectively form a relatively thin coating of wall-forming particles around the crystals or particles(s) of the binder. Mixing may continue while the wall-forming particles continue to agglomerate around the binder, or otherwise bond to increase the wall thickness. If desired, the particles from the first-stage mixer may be passed through a second-stage mixer, where agglomeration or particle bonding may continue for wall formation. A structure with the desired wall thickness may then be passed through a rotary dryer (or similar structure) to remove some or substantially all of the binder from the structure, leaving a structure with the desired hollow core configuration. For such agglomeration, the size of the cavities within the individual granules of the hollow core structure can be controlled by using a selection of binder material. Binders that tend to exist as relatively small particles or crystals can therefore be selected to form individual granules with relatively small core diameters, and binders that tend to exist as relatively large particles or crystals can therefore be selected to form individual granules with relatively large core diameters.

[0083] As discussed above, wall-forming material particles may initially agglomerate around binder material particles, but as the binder material liquefies, it can flow out of the core of the granules being formed and accumulate wall-forming material particles. The discharge of the binder from within the granules being formed and / or formed creates internal cavities within the granules. Some of the binder may remain on one or both of the inner wall surface 19 and the outer wall surface 17 of the wall forming the individual granules. Similarly, some of the binder may remain in the interstitial space 154, as discussed earlier. As a non-limiting example, a formed structure having a substantially hollow core according to this disclosure may be configured such that the amount of binder present in the walls of the hollow core structure is about 0.1% to about 50% by weight, about 1% to about 45% by weight, about 2% to about 40% by weight, or about 5% to about 30% by weight, based on the total weight of the granules.

[0084] In one or more embodiments, a structure having a substantially hollow core may be prepared in a gel-forming process. Such a process may be particularly useful for forming a hollow core structure having a substantially continuous outer wall composed mainly of water and a gel-forming agent, and which is a gel or hydrogel. Such a hollow core structure may be used as is, or it may be further processed to form, for example, an additional outer wall surrounding the gel wall.

[0085] A method for preparing a structure according to such embodiments may include providing an aqueous solution of a gel-forming agent. The gel-forming agent may be a hydrophilic long-chain polymer, in particular, as described separately herein. Preferably, the gel-forming agent and water may be raised to a temperature to form a solution, or specifically heated to a temperature that promotes polymer dissolution. For example, an aqueous solution of the gel-forming agent may be heated to a temperature of about 50°C or higher, about 60°C or higher, or about 70°C or higher, for example, about 50°C to about 95°C, about 55°C to about 90°C, or about 60°C to about 85°C. The solution may be stirred until substantially all of the formed gel is dissolved (for example, as can be confirmed by visual inspection), or it may simply be left to stand at the rising temperature.

[0086] The method may further include bringing a stream of solution into contact with a hydrophobic liquid in a manner adapted or configured to form droplets of a gel-forming agent (e.g., a hydrophilic long-chain polymer). Contact can be made by various means. For example, the stream of solution and the stream of hydrophobic liquid can be poured simultaneously so that the two streams can come into sufficient physical contact to separate the solution into gel droplets. In some embodiments, the hydrophobic liquid can be provided in a container, and an aqueous solution of the gel-forming agent can be poured into the container or otherwise introduced. If desired, the solution may be delivered in substantially droplet form or in the form of a relatively narrow stream for contact with the hydrophobic liquid. For example, the solution may be delivered through a syringe pump or similar device having one or more outlets of preferably small size, e.g., about 0.01 mm to about 2 mm, about 0.05 mm to about 1.5 mm, about 0.1 mm to about 1.2 mm, or about 0.2 mm to about 1 mm in diameter.

[0087] The solution may be at least partially cooled before being combined with the hydrophobic liquid, and / or cooled by contact with the hydrophobic liquid. In some embodiments, pre-cooling may be omitted. Preferably, the hydrophobic liquid is at a temperature lower than the temperature of the gel-forming agent solution. For example, the hydrophobic liquid may be at a temperature of about 45°C or less, about 40°C or less, or about 35°C or less (e.g., about 5°C to about 40°C, about 5°C to about 25°C, or about 5°C to about 20°C). In some embodiments, the hydrophobic liquid may be provided in a refrigerated tank or similar storage unit.

[0088] Optionally, the method may include separating the gel droplets from the hydrophobic liquid. If two flows of material are brought into contact simultaneously, the separation may be performed during the forming process by combining the flows, for example, by passing them through a sieve of appropriate size to capture the gel droplets. Alternatively, if a flow of solution is added to a hydrophobic liquid in a container, the mixture of the hydrophobic liquid and the formed gel droplets may be processed by passing it through a sieve of appropriate size to capture the gel droplets. In some embodiments, a conveyor or similar transport system may be used to move the collected gel droplets (or beads) from the hydrophobic liquid tank.

[0089] In some embodiments, it may be useful to wash the gel droplets with soap, for example, to provide substantially clean gel droplets. This may be achieved, for example, by rinsing with a soap solution, or by temporarily immersing the gel droplets in a soap solution bath and then rinsing with substantially pure water, or by any similar method. This may be beneficial because residual hydrophobic liquid on the gel droplets can make them substantially hydrophobic, potentially reducing their final strength and water absorption properties. By washing with soap, etc., substantially clean gel droplets can be provided.

[0090] It may be even more useful to form conditioned gel droplets by at least partially coating substantially clean gel droplets with a conditioning agent. The conditioning agent can be any material or combination of materials adapted or configured to substantially prevent the gel droplets from adhering to one another. Thus, the conditioning agent may also function as a flow aid. Furthermore, the conditioning agent may be one or more materials useful for improving the adhesion of a coating layer / wall to the gel droplets. In some embodiments, the conditioning agent may be a mixture of an inert powder and an oil. For example, talcum powder, powdered starch (e.g., corn starch, tapioca starch, arrowroot starch, rice starch), grain flour (e.g., oat flour), fumed silica, precipitated silica, powdered sugar, calcium silicate, sodium aluminosilicate, sodium ferrocyanide, potassium ferrocyanide, calcium ferrocyanide, calcium carbonate, magnesium carbonate, cellulose powder, bone phosphate, sodium silicate, silicon dioxide, magnesium trisilicate, potassium aluminum silicate, bentonite, aluminum silicate, stearic acid, polydimethylsiloxane, etc., may be used as inert powders. Suitable oils include silicone oil, mineral oil, dimethicone, etc.

[0091] The addition of conditioning agents may be particularly useful with respect to the subsequent addition of a coating layer onto the gel droplet. For example, clay materials in particular may be formed in the coating layer, which may include contacting the conditioned gel droplet with clay particles or powdered clay (or other materials already described herein). When a coating layer is applied to a gel droplet, it may be useful to carry out a drying step. For example, the gel droplet with the coating layer may be dried at ambient temperature or an elevated temperature, or forced air drying may be utilized. In some embodiments, the gel droplet with the coating layer may be dried at a temperature of about 90°C or higher, about 100°C or higher, or about 110°C or higher (e.g., about 90°C to about 150°C, about 100°C to about 140°C, or about 110°C to about 130°C). Preferably, drying at an elevated temperature may be carried out after the coating is complete. The coating may be carried out using various coating units (e.g., plate granulators, drum granulators, etc.), where the gel droplets may be mixed substantially uniformly with the coating material.

[0092] In one or more embodiments, the disclosure can therefore provide a substantially continuous process for manufacturing a hollow core structure. Such a process may include forming hydrogel beads / droplets, washing the formed hydrogel beads / droplets, and coating the hydrogel beads / droplets using a powdered or granular solid coating material. More specifically, forming beads / droplets may include contacting a hydrogel solution with an optionally refrigerated hydrophobic liquid, which may include delivering the hydrogel solution from a storage container through a syringe pump or similar component that may include multiple outlets. The beads / droplets may form substantially spontaneously in the hydrophobic liquid and may be removed therefrom to a washing / rinsing stage via a conveyor system or similar unit. In the washing / rinsing stage, the beads / droplets may have a residual layer of hydrophobic liquid, which may be substantially or completely removed from the beads / droplets by contact with a detergent solution that may be sprayed or otherwise come into contact with the beads / droplets. The washed / rinsed beads / droplets may optionally be at least partially dried, for example, by passing them through a heater and / or air dryer. The washed / rinsed beads / droplets, optionally at least partially dried, may optionally be pre-conditioned as discussed above. Thus, the beads / droplets may be spray-coated with a suitable conditioning material, or otherwise brought into contact with it. The washed / rinsed and optionally further treated beads / droplets may then be passed through a coating unit, which may consist of one or more mixing stages, where the beads / droplets are brought into contact with a powdered or granular solid coating material until a desired coating thickness is reached. The thus coated beads / droplets may then be passed through a drying unit for drying by heat and / or forced air.The dried beads / droplets may be ready for use, or optionally, they may be passed through one or more further mixing units for the addition of further coating layers, e.g., further conditioning layers and / or further layers of coating material (e.g., bentonite powder or other coating material as described herein). Such a process may be substantially continuous in that beads / droplets are continuously formed and transported from one processing unit to the next along a conveying system or similar preferred system to provide a finished hollow core structure.

[0093] Products and manufactured articles

[0094] Hollow core structures / granules can be used in forming a variety of products. Such products can be defined in terms of their functional aspects and / or in terms of their physical properties, which at least partially arise from the composition of at least one component of the product as a hollow core structure as described herein. The above manufacturing methods make it possible to configure various solid materials (e.g., compounds, minerals, and multi-component mixtures) into hollow core forms that can result in improved properties compared to the same material when provided in its high-density form (i.e., without internal cavities or hollow cores). For example, by providing a material in a hollow core form as described herein, it is possible to provide increased uses and improved performance, such as a reduction in the weight or bulk density of the material, improved product solubility, improved absorption and / or adsorption properties, improved component release, improved flowability of solid granules, or similar properties. With respect to mixtures of different materials, a single component of the mixture may be provided in hollow core form, thus imparting improved properties to the entire mixture of materials. Similarly, multiple or all components of a mixture may be provided in hollow core form. For example, the mixture may include one or more components separately configured as hollow core granules (e.g., a first group of hollow core granules in which the first component is a wall-forming material, a second group of hollow core granules in which the second component is a wall-forming material, and optionally more, groups of hollow core granules, the groups of hollow core granules being mixed). Another example is that the mixture may include one or more components combined as hollow core granules (e.g., a group of hollow core granules in which two or more components are all used as wall-forming materials). Further examples include that the mixture may include any of the above-described types of hollow core granules and one or more components that are not in the form of hollow core granules.

[0095] In some embodiments, products provided in the form of hollow core structures can exhibit improved solubility compared to non-hollow core versions of the material. The improvement in solubility can be particularly evident when comparing materials on a size basis. Granules prepared as hollow core structures having an outer wall containing multiple individual particles of a given material are significantly larger in size than the individual particles of material present in the outer wall of the granules. Larger granules can be configured to decompose immediately in the presence of a suitable solvent, allowing the smaller particles forming the granule walls to dissolve individually. Fully dense particles of material present at substantially the same size as the hollow core granules dissolve significantly more slowly as the solvent slowly penetrates the surface. Thus, granules formed at the walls of individual particles of material exhibit a significantly larger surface area for interaction with the solvent. Similarly, the binder used in forming the granules can be selected for the desired solubility in the solvent. For example, with respect to solid materials intended to dissolve in aqueous or polar solvents, hydrophilic binders, such as various PEG materials, may be used, and these binders contribute at least partially to the rapid dissolution of the granules in the solvent. Similarly, with respect to solid materials intended to be dissolved in nonpolar solvents, hydrophobic binders, such as waxes or hydrophobic polymers, may be utilized, and these binders also contribute, at least partially, to the rapid dissolution of the granules in the solvent. In some embodiments, the time to substantially complete dissolution of a given weight of granules having the hollow core structures described herein may be at least 10%, at least 25%, at least 50%, or at least 75% faster than the time to substantially complete dissolution of the same weight of the same material in a completely dense form (i.e., not in a hollow core form). More specifically, the hollow core form of the material may dissolve substantially at a rate about 10% to about 99%, about 15% to about 95%, about 20% to about 90%, or about 25% to about 80% faster than the non-hollow core form of the same material.

[0096] The properties of hollow core structures described herein as being formed from multiple particles of one or more materials bonded to a wall with a binder material can provide a variety of options for controlled-release compositions. Different materials have different dissolution rates in various solvents and solvent temperatures due to the chemical and / or physical properties of the materials. Based on the specified dissolution rates of the materials, according to this disclosure, it is possible to provide granules of hollow core structures whose walls comprise particles of two or more different materials having two or more different dissolution rates. For example, as will be discussed further herein, the hollow core structures of the present invention may be used in fertilizer products. Various chemical products and compounds useful as fertilizers can exhibit different dissolution or release rates. In particular, "fast-release" fertilizers and "slow-release" fertilizers are well known. If it is desirable to provide a combination of fertilizers with different release rates, particles of fast-release fertilizers and particles of slow-release fertilizers can be combined in a desired ratio and used as wall-forming components for preparing granules of hollow core structures as described above. Therefore, the resulting fertilizer granules have a wall surrounding a hollow core, and the wall contains fast-release fertilizer particles and slow-release fertilizer particles in a designed ratio. When applied to a site where fertilization is required, the fast-release fertilizer particles provide immediate fertilization, while the slow-release fertilizer particles remain for the expected time due to their slow-release properties. The same principle can be applied to any number of solid materials with different dissolution and / or release rates, and as a result, many types of controlled-release granules can be prepared.

[0097] Similarly, controlled release may be achieved by using two or more different forms of the same solid material. For example, the desired material may be provided as two or more different forms of particles exhibiting two or more different dissolution or release rates. Different release rates may relate to particle size, particle purity, the presence of an encapsulation layer, or other recognized ways to affect the dissolution or release rate. For example, a first set of particles of a first size may have a first dissolution or release rate, and a second set of particles of a second different size may have a second different dissolution or release rate. As a further example, a first set of particles that are substantially pure (i.e., formed entirely from a single material or having only trace amounts of impurities) may exhibit a first dissolution or release rate, and a second set of particles may contain an amount of additives (e.g., an inert material or a different desired material having a different dissolution or release rate) such that the particles of the second set have a different dissolution or release rate than the particles of the first set. As yet another example, the first set of particles may be supplied uncoated, and the second set of particles of the same material may be supplied coated or encapsulated such that the coated or encapsulated particles exhibit delayed release compared to the uncoated or unencapsulated particles. These or similar situations can be applied to two, three, four, or more sets of particles, which can then be mixed in a desired ratio and used as a wall-forming material to prepare granules in which the walls surrounding a hollow core contain two, three, four, or more sets of particles having two, three, four, or more different dissolution or release rates. For example, in laundry care applications, it may be desirable to immediately release detergent materials into the cleaning solution, while delayed release of bleaching materials, brighteners, etc.In such cases, the laundry components for immediate release may be provided in an unmodified form, and the laundry components for delayed release may be provided in an encapsulated or coated form, and different materials may then be mixed and used as wall-forming materials to prepare granules of the laundry composition, which, when added to a cleaning solution, immediately releases detergent components while delaying the release of further components (i.e., coated or encapsulated components).

[0098] In some embodiments, providing the material in a hollow core form, as described herein, can be particularly beneficial in providing a reduced product weight without limiting product performance. For example, solid granular products, which are often sold in large quantities, may exhibit undesirably high weight, which can be cumbersome for consumers to carry and handle. By providing such products in a hollow core form, the total weight can be reduced while providing the product in a volume effective for achieving the desired final result, thus avoiding an effective increase in consumer costs to achieve the same result. In other words, the effective volume of the product can still provide substantially the same final result with a reduced product weight, while maintaining approximately the same product cost.

[0099] In exemplary embodiments, such a desired reduction in overall weight can be particularly applied in the field of high-density products, such as animal litter, which is often formed at least partially from clay. Clay is frequently used in animal litter because it is a relatively inexpensive and effective liquid absorbent material. However, clay is relatively dense, making animal litter products considerably heavier, and commercially sold quantities require as much as 30-40 pounds of clay-based litter to fill a large litter toilet. Therefore, the ability to provide hollow core structures as described herein can be particularly useful in forming animal litter with significantly lower weight and further improved absorbent properties. This can be extended to clay-based hollow core structures and non-clay hollow core structures.

[0100] The reduction in weight or mass of a given material by providing it in a hollow core form as described herein may vary based on the density of a substantially pure product. Higher-density materials, when provided in a hollow core form, can reduce the mass or weight of the product more significantly than lower-density materials. In some embodiments, a given volume of material provided in a hollow core form according to this disclosure may have a mass or weight that is at least 5%, at least 10%, at least 15%, or at least 20% less than the mass or weight of the same volume of material provided in its natural or typical non-hollow core form. In certain embodiments, the hollow core version may have a mass or weight that is about 5% to about 60%, about 7% to about 40%, or about 10% to about 35% less than the mass or weight of the product of the same volume of the non-hollow core version.

[0101] In some embodiments, granules formed as a hollow core structure can exhibit an improved ability to absorb and / or adsorb gases and liquids. Thus, materials previously known to exhibit good absorption and / or adsorption properties in their typical high-density forms can have such properties improved by constituting the particles of the material as a wall around a hollow core. Similarly, materials that do not necessarily exhibit absorption and / or adsorption properties in their typical high-density forms can be utilized for such purposes if the particles of the material are constituting a wall around a hollow core. While we do not wish to be bound by theory, it is thought that improvements in absorption and / or adsorption properties may result, at least in part, from an increase in porosity achieved by collectively binding a very large number of smaller particles of the material to form a wall surrounding a hollow core. Similarly, a combination of many small particles in a shell structure can significantly increase the surface area available for absorption and / or adsorption purposes. Furthermore, the addition of a binder in the shell structure can similarly provide absorption and / or adsorption properties that are additive to such properties present in the particles of the solid wall-forming material itself. Such properties could extend to applications in odor absorption (i.e., the capture of odor-causing chemicals that may exist in a substantially gaseous state) and liquid absorption (e.g., cleaning overflows).

[0102] Improved absorption and / or adsorption can, in particular, demonstrate that the same volume or weight of gas or liquid can be absorbed by less weight of hollow core granules compared to the same material in its natural or typical completely dense form (i.e., not in the hollow core form). For example, the hollow core structures of the present invention can provide at least 10%, at least 25%, at least 50%, or at least 75% greater absorption of gas and / or liquid (based on the volume of gas, or based on either the volume or mass of liquid) compared to the same weight of material in a form other than the hollow core form described herein. More specifically, such improvements may be in the range of about 10% to about 95%, about 15% to about 90%, about 20% to about 85%, or about 25% to about 75%.

[0103] In exemplary embodiments, hollow core granules configured to improve gas absorption and / or adsorption and function as deodorants (i.e., configured to absorb, adsorb, or otherwise trap, bind, and / or neutralize odor-causing compounds) can be prepared using a variety of wall-forming materials, a variety of binders, and may contain an optional odor neutralizer. For example, various clays (e.g., bentonite), salts (e.g., sodium bicarbonate), carbon materials (e.g., activated carbon), and highly porous materials (e.g., zeolites) may be effective in capturing odor-causing compounds, and any one or more of such materials, or other materials exhibiting similar effectiveness, may be used as wall-forming materials for the hollow core granules. Suitable binders include materials such as PEGs of various molecular weights (e.g., PEG8000, PEG12000, and / or PEG35000), saturated fatty acids (e.g., stearic acid), and polyoxyethylene fatty ethers (e.g., Brij® S100). The odor neutralizer may be provided as a solid that can be included as a wall-forming material, as a liquid combined with a solid wall-forming material, as a liquid blended with a binder, or as any other suitable form contained in hollow core granules. An example of a suitable odor neutralizer is lauryl methacrylate. Odor masking agents may also be used in a similar manner and may include fragrances, etc., that can deliver a desired odor in an amount sufficient to mask an undesirable odor.

[0104] The improved ability of the hollow core granules described herein to reduce malodors by absorbing, adsorbing, or otherwise binding to odor-causing chemicals or compounds is illustrated in Example 12 herein. Specifically, when a material effective as an odor control agent is used as a wall-forming material in the hollow core granules according to this disclosure, the material in hollow core form is shown to exhibit improved functionality compared to the same material in its natural state. For example, the hollow core form of an odor reducer can exhibit improved malodor reduction compared to the natural form of an odor reducer, in that the detectable concentration of the odor-causing chemical or compound may be less than 10%, less than 25%, less than 50%, less than 75%, or less than 90% after a predetermined contact time between the odor-causing chemical or compound and the odor reducer. The test in Example 12 demonstrated that the odor reducer in hollow core form had a continuous ability to provide improved malodor reduction that increased over time. Thus, the applicable period within the above range may be as short as about one hour or as long as about 100 hours.

[0105] In further exemplary embodiments, hollow core granules, which can be configured to have improved liquid absorption and / or adsorption and thus function for overflow cleaning or similar applications, can be prepared using a variety of wall-forming materials, a variety of binders, and may include optional additives to achieve a predetermined purpose, e.g., decomposition of organic matter. For example, various clays (e.g., bentonite), carbon materials (e.g., activated carbon), and highly porous materials (e.g., zeolites) may be effective for absorbing aqueous and / or non-aqueous liquids in various locations (on land and / or underwater), and any one or more of such materials, or other materials exhibiting similar effectiveness, may be used as wall-forming materials for hollow core granules. Suitable binders can be selected based on the desired application. For example, in a particular embodiment, a binder may be specifically selected to prepare granules for on-land use in absorbing liquids containing hydrocarbons, e.g., various oils. Suitable binders for such purposes include hydrophilic materials, such as PEGs of various molecular weights (e.g., PEG8000, PEG12000, and / or PEG35000), saturated fatty acids (e.g., stearic acid), and polyoxyethylene fatty ethers (e.g., Brij® S100). Clays, such as bentonite, may be particularly useful as wall-forming materials for such applications. In other specific embodiments, binders can be specifically selected to prepare granules for underwater applications, such as cleaning oil spills in marine fields. Suitable binders for such purposes include hydrophobic materials, such as waxes, paraffins, polycaprolactones, ethylene-vinyl acetate copolymers, polypropylene carbonates, poly(tetramethylene oxide) poly(ethylene adipate), poly(trans-butadiene), and thermoplastic polyurethanes (e.g., Carbonate TPU). Here again, various clays may be particularly useful as absorbent wall-forming materials in such applications. The hollow core granules may contain, along with other materials, biological agents and similar materials that are effective in breaking down hydrocarbons or that are otherwise effective in modifying spilled liquids to improve their ease of cleaning.Such components, provided as solids that may be included as wall-forming materials, may be liquids combined with solid wall-forming materials, liquids blended with binders, or may be contained in hollow core granules in any other preferred form.

[0106] In some embodiments, the ability to provide a given material in the hollow core configuration described herein can be beneficial with respect to the processing and use of the material. For example, many solid materials, typically sold in granular form, may exhibit significant dusting during handling due to the presence of fine particles (i.e., a certain amount of material whose size is significantly smaller than the average size of the remaining material). Fine particles may be inherently present in large quantities of certain materials due to the manufacturing process, due to the inevitable crushing of particles during storage and / or handling, or for other reasons. Since the individual particles forming the granules of the hollow core structure are held in place by the presence of a binder, dust reduction can be achieved according to this disclosure. Since the fine particles are bound together or adhered in the walls of the granules and / or in one or more layers of the walls, such fine particles are less likely to float in the air during particle movement. Thus, by providing a composition for a hollow core structure in which individual particles of a solid material are combined with a binder to form one or more walls or shells surrounding the hollow core, the amount of dust associated with a given amount of material can be significantly reduced.

[0107] In addition to reducing dusting, the structure of the hollow core granules (i.e., having a wall of particles and binder surrounding a hollow core) can also result in improved material flowability and / or pourability. Since the individual granules of the hollow core structure are formed by aggregation around binder particles, the individual granules can exhibit a substantial degree of uniformity in either or both size and shape. This can result in an improved appearance compared to particles of the same material in their typical high-density form, which can have a remarkably wide range of particle sizes and / or shapes. On the other hand, the hollow core structure of the present invention can have substantial uniformity in size such that the average particle size can vary by, for example, less than 20%, less than 15%, less than 10%, less than 5%, or less than 2% relative to the median particle size. Such uniformity can improve the way in which the individual granules interact with each other during movement, so that the hollow core structure flows more easily along and around each other.

[0108] In some embodiments, the hollow core granules according to this disclosure can be configured to provide pH adjustment. Thus, the hollow core granules can be added to a substantially acidic material or site (e.g., with a pH less than 7, less than 6, less than 5, less than 4, or less than 3) to make the material or site less acidic, substantially neutral (e.g., with a pH in the range of about 6 to about 8 or about 6.5 to about 7.5), or basic (e.g., with a pH greater than 7, greater than 8, greater than 9, greater than 10, greater than 11, or greater than 12). Alternatively, the hollow core granules can be added to a substantially neutral material or site to make the material or site substantially acidic as defined above, or substantially basic as defined above. Alternatively, the hollow core granules can be added to a substantially basic material or site as defined above to make the material or site less basic, substantially neutral as defined above, or substantially acidic as defined above. pH adjustment can be achieved by using an acidic component as a wall-forming material, using a basic component as a wall-forming material, using a buffer as a wall-forming material, or using several combinations of acidic components, basic components, and buffers as wall-forming materials. Examples of acidic components include organic acids, such as oxalic acid, tartaric acid, citric acid, and maleic acid, which are typically available in solid form. Various salts may also be used, with respect to their ability to release ions upon dissolution, which can be effective in lowering the pH of the surrounding environment. Examples of basic components include materials, such as oxides of various metals, and various salts, such as various carbonates and hydroxides, which can release ions upon dissolution and be effective in raising the pH of the surrounding environment. Buffer solutions can be prepared, for example, by a mixture of salts of similar materials that release ions into the solution at appropriate levels to maintain a substantially consistent pH in the local environment. Once provided as hollow core granules, pH-adjusting hollow core granules can be added to a liquid, for example, and achieve rapid dissolution to adjust the pH in the manner described above.

[0109] In light of the foregoing, it can be seen that this disclosure can encompass a wide variety of products that can exhibit very useful properties, including improvements to typical forms of the same material (maybe more) when not in the hollow core form described herein. This can be extended to a number of chemical products and compounds that are typically useful in various products in their salt forms. Many salts are generally produced in solid form under ambient conditions or are found naturally, and therefore a wide variety of salts may be used as wall-forming materials in the hollow core granules according to this disclosure. The salts that can be provided in the form of hollow core granules according to this disclosure can be organic or inorganic. In some embodiments, suitable salts for preparation as hollow core granules include those having cationic groups, such as aluminum, ammonium, bismuth, calcium, chromium, copper, germanium, iron, lithium, magnesium, manganese, nickel, palladium, platinum, potassium, silver, sodium, sulfur, tin, titanium, tungsten, vanadium, zinc, and zirconium. In further embodiments, suitable salts for preparation as hollow core granules include those having anionic groups, such as acetate, aluminate, ammonium sulfate, benzoate, boride, bicarbonate, bromate, bromide, carbide, carbonate, chloride, chromate, ferrite, fluoride, hydride, hydroxide, iodate, iodide, lactate, manganate, nitrate, nitride, oxalate, oxide, perchlorate, phosphate, phosphide, silicate, silide, stearate, sulfate, sulfide, titanate, tungstate, vanadate, and zirconate. Non-limiting examples of specific salts that can be used for hollow core granules include calcium carbonate, sodium chloride, sodium carbonate, sodium bicarbonate, sodium percarbonate, sodium sulfate, sodium carbonate peroxide, potassium chloride, magnesium carbonate, magnesium sulfate, and the like.

[0110] The ability of compounds, such as salts, to exhibit remarkably improved properties when in the form of hollow core structures can be demonstrated with respect to exemplary embodiments of sodium bicarbonate (NaHCO3) or baking soda. Sodium bicarbonate is known to have a wide variety of uses, one example being its use as a deodorant, taking into account its ability to absorb odor-causing compounds, such as sulfur compounds. As further described herein, particles of sodium bicarbonate can be combined with a binder, such as PEG, paraffin, or other binders, to form granules, where the hollow core is surrounded by one or more walls / shells containing sodium bicarbonate and the particular binder. The resulting hollow core sodium bicarbonate granules can provide improved odor absorption properties than known forms of sodium bicarbonate where the material is simply provided as a powder or in larger solid lumps. Thus, hollow core sodium bicarbonate granules can be particularly useful as deodorants for use in a variety of environments, including refrigerators, trash cans, garbage containers, pet litter boxes, etc. This is shown in Example 12 below, where it was demonstrated that sodium bicarbonate in the form of a hollow core exhibits improved odor reduction with respect to substances such as ammonia and sulfur.

[0111] Therefore, hollow-core sodium bicarbonate is an exemplary embodiment of a substantially pure compound, and such a substantially pure compound can be upgraded for improved use by modifying it to be combined with a binder to form hollow-core granules. Thus, the granules of hollow-core sodium bicarbonate differ from the typical form of sodium bicarbonate in that the granules contain particles of sodium bicarbonate within a shell / wall with a binder, such that the shell / wall surrounds the hollow core. The binder may be substantially inert with respect to the desired use of sodium bicarbonate, but in some embodiments, the binder may be selected to complement the intended use and thus produce an additive effect on the sodium bicarbonate itself. Hollow-core sodium bicarbonate also differs from the typical form of sodium bicarbonate with respect to improved properties, such as improved absorption and / or adsorption, improved dissolution, reduced weight, and other properties, as already discussed above.

[0112] As can be seen from exemplary embodiments in which sodium bicarbonate is used as a wall-forming material for hollow core structures, the present disclosure makes it possible to construct the wall-forming material into a higher-order format so that its usefulness and effectiveness as a standalone product can be improved. However, such improvements are not limited to sodium bicarbonate, and other wall-forming materials described herein can similarly benefit from reconstructing the material from its natural format (i.e., a typical completely dense form of solid material) to a walled format in which particles of the material are arranged in walls together with a binder surrounding a hollow core. Similarly, such improvements are not limited to use as a standalone product. Rather, individual materials upgraded to granules having a hollow core format, such as sodium bicarbonate, can be used as components of various mixtures and compositions defining other types of products.

[0113] For example, taking hollow-core sodium bicarbonate granules as an example, such an upgraded form of the material can be used as a component of a number of useful products. Currently, sodium bicarbonate is used in its typical fully dense form in other formulations, such as laundry detergents, dish soaps, carpet cleaners / deodorizers, animal litter, and personal care products, such as deodorants / antiperspirants, and dental care items (e.g., toothpaste). Therefore, one or more of such products may be modified and improved by replacing the sodium bicarbonate in its typical form with the hollow-core sodium bicarbonate granules according to this disclosure. The thus modified composition can then demonstrate improvements resulting from at least the improved functional aspect of the hollow-core sodium bicarbonate granules. Of course, sodium bicarbonate is used as an exemplary embodiment, and the ability to provide improved products is not limited to the use of hollow-core sodium bicarbonate granules. It is understood that such improvements can be achieved through the upgrading of chemical products, compounds, and complex mixtures and compositions, which may or may not contain sodium bicarbonate as an ingredient.

[0114] Since a wide variety of materials may be used as wall-forming materials, the hollow core granules of the present invention can be configured into a wide variety of products. Non-limiting examples of products that may partially or entirely contain the hollow core granules of the present disclosure include cleaning compositions (e.g., laundry detergents, dish soaps, fabric cleaners, fabric deodorizers, polishing cleaners, plaque removal compositions, disinfectants, etc.), cleaning composition additives (e.g., stain removers, whiteners, brighteners, bleaches, scent boosters, etc.), absorbents, adsorbents, deodorizers, odor masking products, fertilizers, pest control agents, animal litter, animal litter additives, and other consumer and / or industrial products. Any of the foregoing may be functional materials as referenced above, and may also be provided as standalone products that can be added to other products to impart a desired function and / or combined with other products as necessary to achieve additive results.

[0115] In one or more embodiments, products suitable for provision as hollow core granules may include mixtures of one or more chemical products, compounds, or materials that are effective as detergents / cleaners and / or additives useful for combination with detergents / cleaners. Many cleaning products are provided in solid form, typically as powders or other granular forms. Common examples of such compositions include fabric care items (e.g., laundry detergents for use in washing machines, upholstery cleaners, brighteners, whiteners, stain removers, scent boosters, etc.) and dishwashing detergents. According to this disclosure, existing cleaning compositions may be redesigned into an upgraded format in which one or more individual components of the mixture may exist in hollow core form. For example, sodium bicarbonate in such a formulation may be replaced with hollow core granules of sodium bicarbonate. Other individual components of the cleaning composition may be replaced, either alternatively or additionally, with components in hollow core versions. In other embodiments, the entire powder product may be modified so that the entire composition is in the form of hollow core granules. The powder cleaning composition may be a mixture of components that are blended into a substantially homogeneous powder or other granular form. Rather than using it in powder form, the entire mixture may be used as a wall-forming material and mixed with a suitable binder so that the individual particles of the entire cleaning composition aggregate with the binder in one or more walls of the formed granules having a hollow core format. Alternatively, the granules having a hollow core format may be prepared to have two or more walls / shells. In such embodiments, the first part of the cleaning composition may exist as a first inner shell or wall, and the second (or more) part of the cleaning composition may exist as a second (or more) wall or shell outside the inner shell. More specifically, one or more components of the cleaning composition may exist as a first inner shell or wall, and the second (or more) components of the cleaning composition may exist as a second (or more) wall or shell outside the inner shell. In this way, a timed release of individual components of the cleaner may be provided.For example, one or more outer shells in a dishwashing composition may provide a cleaning function, and one or more inner shells of the composition may provide a more desirable enzymatic function or a different function in the later part of the dishwashing cycle. In this way, a single composition can provide a timed release of different components of the composition. Similar effects can be achieved by forming layers in other compositions, such as laundry detergent compositions. In addition to providing a timed release, providing compositions in a hollow core format can provide further benefits. For example, redesigning powdered laundry detergents and similar formulations may be desirable, for example, to reduce the overall product weight, improve solubility (and thus reduce the possibility of detergent residue on cleaned items), etc.

[0116] The cleaning compositions according to this disclosure may consist substantially of only the hollow core granules according to this disclosure. The hollow core granules may also include chemical products, compounds, etc., which have one or more cleaning applications as wall-forming materials, and the wall-forming materials may also optionally include one or more carriers, fillers, inert materials, etc., which do not necessarily provide cleaning functionality. Thus, a cleaning composition consisting substantially of only hollow core granules may be configured as a substantially complete formulation for a designed application (e.g., laundry detergent, dishwashing detergent, etc.), or a cleaning composition consisting substantially of only hollow core granules may be configured as an additive (e.g., bleach, brightener, whitener, stain remover, deodorant, etc.) that can be added to another composition for a desired end application. The cleaning compositions according to this disclosure may also consist of hollow core granules in combination with non-hollow core components. For example, the cleaning composition may be provided as a mixture of components, one or more of which may be provided in hollow core form, while one or more of which remain may be provided in non-hollow core form.

[0117] As is evident from the foregoing, the cleaning compositions according to this disclosure may be a combination of materials that define the entire cleaning composition, or they may be more specialized products provided as additives for cleaning products. Non-limiting examples include additives such as brighteners, non-bleach whiteners (including oxidizing materials), scent boosters, enzymes, deodorizers, stain removers, and other materials useful for cleaning products. Furthermore, as already mentioned, the ability to provide compositions in a hollow core format can be similarly extended to liquid or semi-solid components. In particular, one or more liquid or semi-solid components may be absorbed, adsorbed, or embedded in or on the solid components of the cleaning composition, or on an inert carrier that can be harmlessly dissolved and removed in the cleaning solution.

[0118] In some embodiments, the cleaning product or composition according to the present disclosure may be a fabric cleaner or a fabric cleaning composition. A fabric cleaner may be any product configured to be used with at least textiles or fabrics, such as clothing, upholstery, carpets, rugs, bedding (e.g., sheets, blankets, duvets, bedspreads, quilts, mattresses, etc.), tapestries, etc.

[0119] Fabric cleaners may specifically be laundry detergents. Such compositions are known to contain a number of components, including polymers, surfactants, builders, deodorants, enzymes, oxidizing agents, bleaching components, salts, fragrances, etc. Salts, such as sodium sulfate, sodium carbonate, sodium bicarbonate, sodium chloride, potassium chloride, etc., may be particularly included in laundry detergents. Exemplary embodiments of suitable polymers include polyethylene glycol (PEG) polymers of various molecular weights. Exemplary embodiments of suitable surfactants include anionic, nonionic, zwitterionic, amphoteric, cationic, and combinations thereof. An example of a laundry detergent includes C12-15 ethoxylated alcohol, sodium laureth sulfate, sodium sulfate, sodium carbonate, sodium bicarbonate, disodium distylyl biphenyl disulfonate, modified acrylic acid copolymer, protease enzyme / amylase enzyme, sodium carbonate peroxide, potassium chloride, and fragrance. Such compositions may be provided in solid (e.g., powder) format, and solid detergent particles can be used as wall-forming materials to provide the laundry detergent as hollow core granules. In some embodiments, the product according to the Disclosure may be a laundry detergent prepared by the method described herein, wherein the laundry detergent comprises a mixture of hollow core granules and one or more further components effective in the laundry detergent composition. In further embodiments, the product according to the Disclosure may be a laundry detergent prepared by the method described herein, wherein the laundry detergent comprises hollow core granules prepared such that a plurality of individual particles of at least one wall-forming material comprise particles of the laundry detergent composition.

[0120] Fabric cleaners may also be provided in more specialized forms to deliver the designed effect. Various functional formulations are possible to design products that can be used as additives in fabric cleaning, particularly laundry care. Exemplary embodiments of such additive formulations include scent boosters, stain removers, brighteners, whiteners, bleaches, etc. Examples of scent boosters include sodium chloride builders, fragrances, sodium bicarbonate builders, hydrated silica processing aids, sorbitan oleate surfactants, and colorants. Such compositions may also be provided in solid (e.g., powder) form, using solid particles as a wall-forming material. Scent booster formulations can be provided as hollow core granules. Examples of stain removers include sodium carbonate, sodium percarbonate, C12-15 linear alcohol ethoxylates, fragrances, and blue salt. Such compositions may be provided in solid (e.g., powder) format, and the solid particles can be used as wall-forming materials to provide the stain remover formulation as hollow core granules. Other additive formulations for fabric care can similarly be formulated to provide products as hollow core granules.

[0121] Dishwashing detergents, which may be supplied in the form of hollow core particles, can also be formulated in the same manner. Any known solid dishwashing detergent may be formulated in this manner. Furthermore, individual components of a dishwashing detergent may be supplied as additives or otherwise formulated individually as hollow core granules that can be mixed with other components of a dishwashing detergent that is not in hollow core format.

[0122] Other types of household cleaners can also be subject to such redesign. For example, in the field of fabric care, carpet cleaners or other upholstery cleaners are often supplied in powder form, and such compositions can be improved by redesigning them into the hollow core format described herein. For example, sodium bicarbonate may be used in carpet cleaners to remove odors and provide a cleaning effect, and providing sodium bicarbonate as a wall-forming material for hollow core granules can be effective in improving activity in the end use, as such a format provides improved absorption and / or adsorption. Other components of such cleaners may be included additionally or alternatively in products in the hollow core format. Similarly, entire carpet or upholstery cleaning compositions may be supplied as hollow core granules that can be applied to the material to be cleaned. The applied granules may be vacuumed or otherwise removed at appropriate times, or, in some embodiments, the hollow core granules may be subjected to external forces (e.g., walking or use of machinery) to achieve decomposition of the hollow core granules into a finer powder form. Such mechanical action can be effective, for example, in improving the cleaning effect before removing the composition by vacuuming carpets, and in improving odor removal.

[0123] In some embodiments, hollow core granules may be specifically configured to decompose upon application of an external force. The external force may be friction, wiping, scrubbing, or other physical pressure typically applied during surface cleaning. More specifically, upon application of an external force, the hollow core granules may be configured to break into multiple parts, each containing a separate group of wall-forming material particles. In other words, the entire granule breaks into multiple subunits having a size smaller than the original granule but larger than the size of the individual wall-forming material particles, because the particles remain aggregated in each of the subunits. However, during the application of force, the individual particles may also be released along with the multiple subunits. During further or continued application of force, the multiple subunits may further decompose into even smaller subunits and / or individual wall-forming material particles.

[0124] As discussed above, the usefulness of hollow core structures can be extended to abrasive-type cleaners, particularly to cleaning products. As used herein, abrasive-type cleaners are intended to mean cleaners in which cleaning is achieved at least partially by the mechanical action of solid particles that physically remove deposits from a surface through a scrubbing action. Such cleaners can also achieve cleaning by their cleaning power, in addition to mechanically scrubbing particles along the surface to be cleaned. As discussed herein, the granules of a hollow core structure have at least one wall formed of smaller wall-forming material particles. If the wall-forming material is effective as an abrasive-type cleaner, the hollow core granules formed therefrom can exist as relatively large particles that can provide a "rough" abrasive surface, and the mechanical scrubbing action can gradually decompose the hollow core granules into finer particles. The result is analogous to surface sanding, where a rough surface with low grit is used first for bulk removal of material from the surface, and then a surface with higher grit is used for smoothing. The granules of the hollow core structure can similarly function as a low-grit coarse abrasive for bulk removal of residues and buildups, and as the granules break down into finer wall-forming particles, such particles function as a higher-grit abrasive to provide a better cleaning effect for removing smaller amounts of the residues and buildups. Furthermore, the binder material can be selected to control how easily the hollow core granules break down, how quickly the hollow core granules dissolve in the solvent, and to provide an additive cleansing effect. In addition, the hollow core format can provide the user with tactile feedback as an indicator of the effectiveness of abrasive cleaning. Larger hollow core granules impart a significantly different vibration than the finer wall-forming particles. Similarly, since the hollow core granules can be configured to break down under stress, for example, pressure during cleaning, the breakdown of the granules into finer wall-forming particles also provides tactile perception of how the cleaning action is progressing.Therefore, hollow core granules can be configured to successfully decompose into smaller particles, providing layered sculpting effectiveness due to the difference in cleaning ability provided by wall-forming particles of different sizes, intact hollow core granules, and intermediate-sized fragments of the granule walls when the granule walls decompose.

[0125] Similar to the polishing cleaners mentioned above, the hollow core granules of this disclosure can also be used as polishing agents. In particular, one or both of the wall-forming material and the binder can be selected to provide polishing properties. Similarly, the wall-forming material particles may be selected in size to provide the desired level of abrasiveness required to achieve a polishing effect without excessively scratching or damaging the material during polishing. In other respects, the hollow core polishing granules may be functionally similar to the abrasive cleaning granules described above.

[0126] In some embodiments, the hollow core granules of the present disclosure can be used in personal care articles. Specific examples lie in the realm of deodorants / antiperspirants. Further examples include exfoliating products, where the hollow core granules can provide a relatively coarse level of exfoliation at the initial larger granule size, and then a progressively smoother level of exfoliation as the hollow core granules decompose into individual wall-forming particles of significantly smaller size. Binder materials in such applications can be customized to provide additional skin cleansing and / or skin lubrication effects as the granules decompose and / or dissolve in water.

[0127] Dental care products are another example of products that can be improved by the use of hollow core granules. More specifically, the hollow core granules described herein may be used in forming toothpaste compositions. One or more individual components of a toothpaste composition may be provided as hollow core granules incorporated into an entire paste, gel, or similar composition used for plaque removal. For example, sodium bicarbonate is a common component in toothpaste compositions, and sodium bicarbonate may be present in the composition as hollow core granules. Similarly, since many plaque removal compositions utilize at least mild abrasive particles, such particles may be incorporated into the hollow core granules as at least one of the wall-forming materials. Furthermore, binder materials may also be selected to improve the activity of the wall-forming materials and / or to improve the dissolution of the wall-forming materials for rapid deployment during brushing. Alternatively, the entire plaque removal composition may be redesigned as a hollow core structure, which can then be combined with a substrate or carrier material to form a paste, gel, etc.

[0128] The use of hollow core granules can also provide novel plaque removal formulations. For example, instead of incorporating hollow core granules into a plaque removal gel or paste, the hollow core granules may comprise substantially the entirety of the plaque removal composition. In exemplary embodiments, a complete or substantially complete plaque removal composition can be used as a wall-forming material, and the resulting hollow core granules are effective as “toothpaste bits” that can be poured into the mouth for plaque removal. Similarly, multiple hollow core plaque removal granules may be combined into a tablet or similar form, resulting in a single “tablet” being inserted into the mouth for plaque removal. More specifically, the toothpaste bit or toothpaste tablet, once inserted into the mouth, may be chewed, resulting in the abrasive particles removing debris and other substances from the user’s teeth and / or gums. Here again, the choice of binder material may be effective in making the plaque removal granules more easily broken down or lasting longer, and as a result, the effective usage time may be customized. Furthermore, the binder may be effective in providing plaque-removing properties so that it is at least partially effective in removing debris or other material from the teeth and / or gums. Like other hollow core granules for abrasive cleaning, plaque-removing hollow core granules can provide varying levels of cleaning efficacy as the hollow core structure successfully breaks down into finer particles.

[0129] Cleaners, detergents, and similar products may be prepared as substantially "simple" products having only a few components, where one or more of the relatively few components used in such products may exist in a hollow core format, or substantially the entire composition defining the product may exist in a hollow core format. Other products of such types may be relatively complex in that they contain a large number of components. Here again, one or more of any of the components may be in a hollow core format, or substantially the entire composition may be in a hollow core format. However, in some types of compositions, it may be more typical that only the main component is in a hollow core format. Thus, the presence of only the main component in a hollow core format is considered herein. However, many consumer products may contain a wide variety of classes of materials, and it is understood that any further components that may be used in any product or manufactured article included in this disclosure, including animal litter, laundry products, dishwashing products, personal care articles, etc., may be included in such products or manufactured articles in the hollow core format described herein. Therefore, it is expressly intended that any of the following additives may be used in any product or manufactured article in which the component is understood to be typically used: fillers, binders, preservatives, flavorings, salts (e.g., carbonates, bicarbonates, chlorides, etc.), fluorescent agents (e.g., brighteners and / or whiteners), disinfectants, enzymes, antimicrobial agents, oxidizing agents, deodorants, pH adjusters, dyes, colorants, etc.

[0130] In some embodiments, the hollow core granules described herein can be useful for forming orally administered nutritional supplements. This allows for the provision of a wide variety of nutritional supplement forms to offer improved properties, whether the article is configured to be chewable or to be swallowed whole. With regard to the latter format, many nutritional supplements suffer from poor release of vitamins(s), minerals(s), fiber, probiotics, enzymes, amino acids, proteins, or other supplemental agents(s) typically found in various nutritional supplements. This often results from insufficient solubility of the entire pill or tablet form. However, as discussed above, the hollow core structures according to this disclosure can exhibit improved solubility due to the ability of the wall to rapidly decompose into significantly smaller particles used as wall-forming material, and due to the ability to customize the binder to the environment in which dissolution is carried out, such that the binder itself dissolves immediately in the contact solvent. Because smaller wall-forming particles provide a much larger surface area, the rapid breakdown of larger hollow core granules into individual wall-forming particles can provide rapid release and rapid uptake of the nutritional supplement(s) in the user's digestive system. Furthermore, the hollow core format can enable various combinations of components for timed release. As will be discussed separately herein, coating, encapsulation, and other methods can be employed to provide a specific amount of individual particles of one or more wall-forming materials in a delayed-release or sustained-release form. Thus, when hollow core granules of a nutritional supplement are ingested, at least a portion of the nutritional supplement used as wall-forming particles can provide substantially immediate release (if desired), and at least a portion of the nutritional supplement used as wall-forming particles can provide delayed and / or sustained release (if desired). Similarly, since not all nutritional supplements are immediately absorbed in the stomach and / or may be partially or completely broken down in the stomach, this disclosure makes it possible to provide at least a portion of nutritional supplement particles in a coated or encapsulated form that can withstand the highly acidic environment of the stomach but are released in the small intestine for the necessary absorption.Therefore, the ability to provide different nutritional components in different formats enables highly customizable nutritional supplement compositions in which the nutritional material exists as a wall-forming material for hollow core granules.

[0131] Similar to nutritional supplements, hollow core granules can be configured as other personal care products intended for oral intake. For example, laxatives, antacids, and similar materials may be used in hollow core granules. Materials such as PEG are known to function as laxatives, and hollow core granules may be prepared using a PEG binder for wall-forming materials that may be substantially inert and may also constitute a laxative or stool softener, or provide additional benefits such as being a fiber supplement or an antacid (e.g., sodium bicarbonate).

[0132] Since some users may have difficulty swallowing pills, tablets, capsules, etc., the hollow core granules of the present invention can be configured so that the nutritional supplement is in a chewable format. Specifically, the nutritional material may again be used as the wall-forming material of the hollow core granules, but the granules can be configured to be easily chewed in the user's mouth and / or to dissolve rapidly so that the supplement can be provided in a convenient form (e.g., solid dose relative to liquid dose) while still being easily ingested. Furthermore, various additives can be combined with the nutritional supplement to provide hollow core granules with a highly palatable composition. For example, sweeteners, flavorings, or other ingestible materials may be used as part of the wall-forming material so that nutritional components that may otherwise have bitterness, sourness, etc., can be masked by the additives. Furthermore, at least a portion of the binder may also be configured to impart a highly palatable quality in order to mask any unpleasant taste associated with the nutritional supplement itself. Nutritional supplements containing vitamins(s), minerals(s), fiber, probiotics, enzymes, amino acids, proteins, or other supplemental agents(s) typically found in various nutritional supplements can be supplied in bulk format, and the mass or volume of the hollow core granules shall be provided with dosing instructions for the amount of hollow core granules to be ingested to deliver the recommended daily dose or other dose of the supplement(s) contained therein. Alternatively, pre-administered amounts of hollow core granules may be combined into a single unit, for example by the use of a binder, so that the hollow core granules are held together in a block, wafer, or similar unit format from which the user may chew to release the hollow core granules.

[0133] An exemplary embodiment of a nutritional supplement is a vitamin D supplement, which comprises dextrose, microcrystalline cellulose, magnesium stearate, chamomile powder extract, flavorings, and vitamin D. These components are formulated and then used as wall-forming materials in the hollow core granules described herein. Any nutritional supplement can be similarly formulated for the preparation of supplements in a hollow core format.

[0134] In some embodiments, the hollow core structures of the present invention can be particularly useful for forming animal litter. As previously stated herein, clay is often the main component of animal litter products due to its relatively low cost and particularly good effectiveness for liquid absorption. However, clay is relatively dense, making animal litter products considerably heavier, and commercially sold quantities require as much as 30-40 pounds of clay-based litter to fill a large litter toilet. However, clay may be particularly suitable for use as a wall-forming material to produce clay as hollow core granules having walls containing smaller clay particles and a binder. Thus, the resulting hollow core clay granules can be particularly useful for forming animal litter with significantly lower weight and even improved absorption properties. This can be extended to animal litter having hollow core clay granules and hollow core granules formed from different wall-forming materials.

[0135] Accordingly, the present disclosure can provide an animal litter composition that comprises at least one of its components in the form of hollow core granules and can exhibit improved properties, including but not limited to a reduction in the overall weight of the composition. The hollow core granules may be present in the animal litter in a specified amount, for example, about 1% by weight or more, based on the total weight of the animal litter composition. In further embodiments, one or more types of hollow core granules may be present in the animal litter composition in amounts (independent of each other) of about 1% to about 95% by weight, about 2% to about 75% by weight, about 3% to about 60% by weight, or about 5% to about 50% by weight, based on the total weight of the composition. In some embodiments, the material present as hollow core granules may be present in relatively low concentrations, for example, about 1% to about 10% by weight, about 1.25% to about 7.5% by weight, or about 1.5% to about 5% by weight, based on the total weight of the animal litter composition. This may relate to components such as sodium bicarbonate, which may be useful as a deodorizing agent, fragrance, or other components typically present in animal litter. In further embodiments, the material present as hollow core granules may be present at relatively high concentrations, for example, about 10% to about 90% by weight, about 20% to about 85% by weight, or about 25% to about 75% by weight, based on the total weight of the animal litter composition. This may relate to components such as liquid absorbents (e.g., clay) or fillers. In other embodiments, the hollow core granules in the animal litter may be defined in terms of the volume ratio of the material, since the hollow core version is expected to be significantly lighter than the non-hollow core version of the same material. For example, the total content of hollow core granules in the animal litter may be in the range of about 5% to about 98% by volume, about 10% to about 95% by volume, about 20% to about 90% by volume, or about 30% to about 80% by volume, based on the total volume of the animal litter composition. Other concentration ranges already mentioned above may be used on a volume basis. This may include low-concentration and / or high-concentration components.

[0136] Animal litter may contain a variety of components, and it is understood that the animal litter compositions according to this disclosure may contain one of the following components in the form of hollow core granules. Similarly, the animal litter compositions of the present invention may contain two, three, four, or more of the following components in any combination in the form of hollow core granules. Non-limiting examples of the types of components that may be used in animal litter and may exist in the form of hollow core granules include liquid absorbents, fillers, flocculants (or flocculation-enhancing materials), binders, preservatives, biocides such as benzisothiazolinone, methylisothiazolon, dust removers, fragrances, bicarbonates, and combinations thereof.

[0137] Suitable fillers for use in the animal litter composition of the present invention include a variety of materials that can be non-absorbent, insoluble substrates or absorbent substrates. In one or more embodiments, useful fillers include absorbent substrates, such as non-aggregating clays. Non-limiting examples of useful non-aggregating clays include attapulgite, fuller's earth, calcium bentonite, palygorskite, sepiolite, kaolinite, illite, halloysite, formite, vermiculite, or mixtures thereof. Suitable fillers according to this disclosure may also include a variety of non-absorbent, insoluble substrates, such as non-clay materials. Non-limiting examples of non-clay materials that can be used include zeolite, crushed stone (e.g., dolomite and limestone), gypsum, sand, calcite, recycled waste materials, and silica. For example, an animal litter composition may contain one or more fillers in amounts of about 0% to about 75% by weight, about 10% to about 70% by weight, about 25% to about 65% by weight, or about 40% to about 60% by weight, based on the total weight of the animal litter composition or by volume based on the total volume of the animal litter composition. Such fillers may exist in a typical non-hollow core format, or as hollow core granules, or as one of several components used as wall-forming materials for hollow core granules.

[0138] A description of suitable flocculants is provided in Miller et al., U.S. Patent No. 8,720,375, which is incorporated herein by reference. Useful flocculants are materials suitable for promoting the adhesion of fine-sized particles of litter granules to each other and the adhesion of particles that form aggregates when wet. Preferably, the flocculant enables the formation of gelled aggregates when exposed to a liquid such as animal urine. The flocculant may be provided as a mixture (e.g., in particulate form) with further components of animal litter. In some embodiments, the flocculant may be provided as a coating on at least some of the other components forming the animal litter (e.g., as a coating on at least some of the filler material). Such a coating may be provided by any known method, e.g., by spraying. If desired, the flocculant may be provided as an outer layer / wall on a hollow core structure, as already described above. For example, the flocculant may be coated on a hollow core structure having a clay wall and / or a sodium bicarbonate wall. Non-limiting examples of materials suitable for use as flocculants include naturally occurring polymers, semi-synthetic polymers, and sealants. Exemplary embodiments of naturally derived flocculants include various starches, including corn starch; various gums, such as gum arabic, karaya gum, tragacanth gum, gatchigum, guar gum, and xanthan gum; and alginates, carrageenan, pectin, dextran, gelatin, gluten, dried plants of the Plantago family; polyvinyl alcohol; polyvinyl esters, such as polyvinyl acetate, polyvinylpyrrolidone, polyvinyl oxazolidone, polyvinylmethyloxazolidone; copolymers; and mixtures thereof. Exemplary embodiments of semi-synthetic polymers include cellulose ethers (e.g., methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, ethylhydroxyethylcellulose, methylhydroxypropylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, or mixtures thereof); and guar gum derivatives. The amount of any flocculant present in the animal litter composition may vary based on the overall composition.For example, if a larger amount of non-absorbent filler is used, it may be useful to include a larger amount of flocculant. In some embodiments, the flocculant may be present in a total amount of 0.1% to about 6% by weight, about 0.2% to about 5.5% by weight, about 0.3% to about 5% by weight, or about 0.5% to about 4% by weight, based on the total weight of the litter composition or in volume based on the total volume of the litter composition.

[0139] Within the range of containing one or more binders, preservatives, dust removers, fragrances, bicarbonates, etc., such materials may be present independently in any amount up to about 5% by weight, up to about 2% by weight, up to about 1% by weight, or up to about 0.5% by weight, for example, about 0.01% to about 5% by weight, about 4% by weight, about 3% by weight, about 2% by weight, or about 1% by weight, based on the total weight of the animal litter composition. Alternatively, such amounts may be based on volume based on the total volume of the litter composition. Furthermore, it is understood that any one or more of such materials may be expressly excluded from the animal litter composition of the present invention.

[0140] In some embodiments, the product according to the Disclosure may be animal litter prepared by the method described herein, such that the animal litter comprises a mixture of hollow core granules and one or more further components effective in the animal litter composition. In further embodiments, the product according to the Disclosure may be animal litter prepared by the method described herein, such that the animal litter comprises hollow core granules prepared such that at least one of the individual particles of wall-forming material comprises clay particles or sodium bicarbonate particles.

[0141] In addition to litter compositions, this disclosure can be further extended to various additives that may be used with cat litter. For example, various odor masking agents or deodorizers may be available in solid form, and such materials may be provided in the form of hollow core granules as described herein. Non-limiting examples of litter additives that may be provided in the form of hollow core granules include deodorizers, flocculants, dust removers, fragrances, odor masking agents, etc. Any one or more materials useful in pet litter may be formulated individually or together in the form of hollow core granules.

[0142] As already discussed herein, hollow core granules can be particularly useful in fertilizer compositions. Fertilizers are typically recognized as compositions that provide nitrogen, phosphorus, potassium, or other minerals necessary for plant health, such as so-called micronutrients (e.g., boron, chlorine, copper, iron, manganese, molybdenum, and zinc). Fertilizers can be particularly nitrogen sources, and examples of nitrogen sources include materials that can provide nitrogen as one or more of the following: amides, e.g., urea, ammonium urea nitrate (UAM), or polymer-encapsulated urea; ammonium compounds, e.g., ammonium bicarbonate, ammonium sulfate, ammonium chloride, etc.; and nitrates, e.g., sodium nitrate, calcium nitrate, and ammonium nitrate. Fertilizers can be particularly phosphorus sources, and examples of phosphorus sources include materials that can provide phosphorus in its elemental form or as a phosphate. Fertilizers can be particularly potassium sources, and examples of potassium sources include materials that can provide potassium in its elemental form or as a salt, e.g., potassium. Fertilizers can be sources of micronutrients in particular, and examples of sources of micronutrients include materials that provide the micronutrients mentioned above or otherwise acceptable micronutrients. Other materials that may be considered to fall within the group of fertilizers used herein may include materials commonly used to adjust soil pH. Materials that raise soil pH include lime, which may exist more specifically as calcium carbonate, or calcite limestone, or dolomite limestone (a combination of calcium carbonate and magnesium carbonate). Materials that lower soil pH include sulfur, or sulfur-containing minerals or sulfur-containing compounds.

[0143] Any one or more materials suitable for use as fertilizer may be used as wall-forming materials for the hollow core granules described herein. Thus, fertilizer materials available in solid form may be provided as relatively small particles partitioning one or more walls / shells in the hollow core granules. Upon delivery to the site of use, the fertilizer particles may be released from the relatively large granules for dissolution in the soil. Fertilizer materials available in liquid form may be combined with particles of an absorbent or adsorbent material, such as clay, so that a liquid fertilizer is thereby encompassed. The combined material particles may then be used to prepare hollow core granules of fertilizer. Upon delivery to the site of use, the fertilizer may be released from the carrier particles, and any remaining clay particles may be incorporated into the soil or other delivery site without harm.

[0144] Various chemical products and compounds useful as fertilizers can exhibit different dissolution and / or release rates. In particular, "fast-release" and "slow-release" fertilizers are widely known. When it is desirable to provide a combination of fertilizers with different release rates, fast-release fertilizer particles and slow-release fertilizer particles can be combined in a desired ratio and used as wall-forming components for preparing granules in a hollow core structure as described above. Thus, the resulting fertilizer granules have a wall surrounding a hollow core, which contains fast-release fertilizer particles and slow-release fertilizer particles in a designed ratio. When applied to a site requiring fertilization, the fast-release fertilizer particles provide immediate fertilization, while the slow-release fertilizer particles remain for the expected time due to their slow-release properties. The same principle can be applied to any number of solid materials with different dissolution and / or release rates, resulting in the preparation of many types of controlled-release granules. Alternatively, fertilizers with different release rates may be provided in separate hollow core granules. These separate hollow core granules can then be combined in a desired ratio when in use.

[0145] In some embodiments, controlled release of fertilizer may be achieved, in particular, by using encapsulation methods as already described above. For example, a particular fertilizer may be provided in a microencapsulated or other encapsulated form such that the fertilizer material is released only after dissolution, decomposition, etc., of the encapsulated material. Encapsulated fertilizer particles may be used as a wall-forming material (alone or in combination with other fertilizer particles in rapid-release and / or controlled-release forms) to provide hollow core fertilizer granules exhibiting controlled release. Coating techniques may also be used as a means to provide liquid components as wall-forming materials. As an example, polymer-encapsulated urea particles may be used as a wall-forming material that can be combined with a binder to prepare hollow core fertilizer granules. In further embodiments, controlled release may be achieved by the selection of a binder material. For example, the binder may be selected based on a specific solubility such that the fertilizer particles in the walls of the hollow core granules are released only when the binder dissolves. Similarly, hollow core fertilizer granules may have multiple walls, shells, coatings, etc., having different properties to control the release of one or more fertilizer components therefrom. Different walls, shells, coatings, etc., may release their fertilizer components only under specific conditions, and / or may exhibit different dissolution properties so that controlled release can be achieved based on the dissolution / decomposition of multiple walls, shells, coatings, etc. This can be characterized as a multi-stage release fertilizer or a controlled release fertilizer.

[0146] Fertilizer compositions may be applied to the site of use by various methods. Solid fertilizer compositions may be applied directly to the soil to release fertilizer components by dissolving over time. However, other fertilizer compositions may preferably be mixed with a solvent and then sprayed to the delivery site. The improved dissolution rate provided by utilizing the hollow core format described herein can be beneficial for such applications. In particular, solid hollow core fertilizer granules may be supplied in bulk, and the desired mass or volume of solid hollow core fertilizer granules can then be added to a tank sprayer or similar device immediately before application. Since the hollow core format can significantly reduce the dissolution time of the material, the hollow core fertilizer granules can dissolve rapidly without significant delay in a tank sprayer or similar device for application at the site of use. Therefore, hollow core granules can be particularly useful in large-scale agriculture, etc. Similarly, since the hollow core format significantly reduces the weight of the material, this can further improve the ease of application of the fertilizer.

[0147] The rapid dissolution of hollow core granules can also be advantageous for environmental safety. Fertilizer runoff can be problematic due to its passage into waterways (e.g., rivers, streams, ponds, or even sewage drains). Fertilizer particles can be easily washed into such waterways by heavy rain if the particles are not substantially decomposed or dissolved. Since the hollow core format can significantly accelerate dissolution and / or decomposition, the use of the hollow core format for fertilizers can mitigate such potential problems. As can be seen in the attached examples, hollow core fertilizer granules formed using bentonite as the wall-forming material and PEG8000 as the binder have been shown to dissolve in water in seconds. This illustrates the ability of this disclosure to provide a form of hollow core fertilizer granules that is conveniently stored and transported (solid vs. liquid), easier to handle (e.g., reduced weight), and rapidly dissolves upon contact with water to release fertilizer components.

[0148] In exemplary embodiments, hollow-core fertilizer granules can be prepared using a variety of wall-forming materials and binders. For example, various clays (e.g., bentonite), salts (e.g., sodium bicarbonate, magnesium sulfate, etc.), and similar materials can be useful as wall-forming materials, along with any specific solid fertilizer material that may be contained in the granules. Clay is particularly useful because such components can effectively bind various types of fertilizers, release the fertilizer into the soil, and then remain in the soil as an inert additive. Polymer-encapsulated fertilizers can be particularly utilized, with encapsulated urea and encapsulated phosphates being exemplary embodiments. Suitable binders include hydrophilic materials, such as PEGs of various molecular weights (e.g., PEG8000, PEG12000, and / or PEG35000), or similar materials that dissolve immediately in the soil for the decomposition of the granules and the release of fertilizer material therefrom.

[0149] Other types of materials that may be desirable for environmental applications may also benefit from being provided in a hollow core format. Pest control agents can include, for example, a wide variety of chemical products, compounds, etc., configured for the control of pests, insects, etc. The group of pest control agents can include, for example, algicidal agents, antimicrobial agents, biological pest control agents, disinfectants, fungicidal agents, herbicides, insecticides, acaricides, mollusk control agents, ovicidal agents, repellents, rodenticides, etc. Thus, the use of the term “pest control agent” herein can be understood to refer to any of the above exemplary embodiments of materials useful for the control of undesirable species (pests, insects, weeds, etc.). Many such materials are generally sold in particulate form for application in a spreader or by hand. Pest control agents may be designed so that improved performance is achieved by wetting after application. This may be necessary to ensure that the active ingredient is dispersed in the soil or other application point and / or to limit contact between the active ingredient and humans, pets, or wildlife. Furthermore, wetting may be necessary for dispersion and soil contact in order to prevent the unnecessary runoff of potentially hazardous chemicals into waterways.

[0150] Any chemical product, compound, or similar material effective as a pesticide may be used in forming the hollow core granules according to this disclosure. Specifically, the pesticide may be considered an activator in light of prior recognition of substances exhibiting pesticide activity. Non-limiting examples of pesticides that may be used in accordance with this disclosure and may be considered pesticide activators include bifenthrin, acephate, carbaryl, cyfluthrin, 2,4-dichlorophenoxyacetic acid, trifluralin, chlorpyrifos, arethrin, cypermethrin, disulfone, 2,6-dichlorobenzonitrile, metrachlor, cyhalosrin, hydramethylnon, atrazine, chlorothalonil, mycrobutanil, dicamba, azadirachtin, captan, diazinon, and others. This includes rubofuran, methomyl, deltamethrin, propiconazole, borate, dinotefuran, dithiopyr, isoxaben, prodiamine, quinchlorac, cethoxydim, iron(III) phosphate, mancozeb, thiophanate-methyl, esfenvalerate, tebuconazole, resmethrin, glyphosate, malathion, permethrin, imidacloprid, fipronil, abamectin, spinosad, triclopyr, piperonyl butoxide, pendimethalin, oryzalin, and oxadiazone.

[0151] In a manner similar to that already discussed above with respect to fertilizers, any one or more pesticides may be utilized in hollow core granules. In particular, one or more pesticides may be used as wall-forming materials for the hollow core granules described herein. Thus, pesticides available in solid form may be provided as relatively small particles that partition one or more walls / shells in the hollow core granules through combination with one or more binders. Upon delivery to the site of use, the pesticide particles may be released from relatively large granules for dissolution and / or dispersion in the soil. Pesticides available in liquid form may be combined with particles of an absorbent or adsorbent material, such as clay, so that the liquid pesticide is thereby encompassed. The combined material particles may then be used to prepare hollow core granules of pesticides. Upon delivery to the site of use, the pesticides may be released from the carrier particles, and the remaining clay particles may be incorporated into the soil or other delivery site without harm.

[0152] Pest-killing hollow core granules can be constructed using a single pesticide or a combination of pesticides having the same or different activity. When multiple different pesticides are used as wall-forming materials in the hollow core structure, the different pesticides can be combined in a desired ratio for combination with one or more binders for preparing the granules of the hollow core structure. Thus, the resulting pesticide granules have walls surrounding the hollow core, and these walls contain particles containing different pesticides in a designed ratio.

[0153] Pest control compositions may be applied to the site of use by various methods. Solid pest control compositions may be applied directly to soil or other surfaces for the release of pest control components(s). However, other pest control compositions may preferably be mixed with a solvent and then sprayed to the site of delivery. The improved dissolution rate provided by utilizing the hollow core format described herein can be beneficial for such applications. In particular, solid hollow core pest control granules may be supplied in bulk, and the desired mass or volume of solid hollow core pest control granules can then be added to a tank sprayer or similar device immediately before application. Since the hollow core format can significantly reduce the dissolution time of the material, the hollow core pest control granules can dissolve rapidly without significant delay in a tank sprayer or similar device for application at the site of use. This makes it possible to form lightweight compositions of solid format that are easy to store and transport, while still allowing for rapid delivery at the time of use.

[0154] For example, in the case of herbicides requiring direct plant contact, or pesticides sprayed for application in homes, etc., pesticides requiring delivery in liquid format can be beneficially constructed in solid format by combining the liquid pesticide with carrier particles before incorporating carrier particles loaded with the pesticide as wall-forming material in hollow core granules. The formed hollow core pesticide granules can then be dissolved in a suitable solvent before application. Suitable carrier particles and binders can be similarly selected to be dissolved and delivered together with the pesticide as inert components or as additives. For example, solid pesticide particles may be used as carriers for liquid pesticides. Similarly, pesticide hollow core granules may be prepared by using one or more pesticides as wall-forming material, and one or more additional pesticides may be used as coatings on the formed particles to provide mixed delivery of multiple pesticides in a given granule.

[0155] The ability to provide pesticide compositions having different release characteristics can be particularly beneficial. For example, some pesticides may pose a risk if ingested by wildlife or livestock, and it may be beneficial to reduce the time over which undesirable interactions can occur by rapidly dissolving, decomposing, etc., such pesticides. This can be a problem associated with many solid forms of pesticides that may persist in the environment for a considerable period of time. However, such materials may be provided in the form of a hollow core that exhibits rapid dissolution, decomposition, etc., according to this disclosure.

[0156] Hollow core pesticides can also be configured to exhibit specific properties that make them highly useful in various environments. For example, hollow core granules may be prepared to exhibit buoyancy, which can make them particularly useful for application in water. Ponds or other freshwater areas may require treatment for various pests, but it may be difficult to provide solid particles in a form that persists on the surface rather than immediately dissolving or sinking. The selection of a binder and / or the inclusion of additives in the wall-forming material can be effective in making the entire granule buoyant for a sufficient amount of time for the pesticide to be released onto the water surface. For example, a hydrophobic binder may be used for this purpose, and additives, such as cellulose-based materials (e.g., cellulose-based aerogel), straw (or similar buoyant plant materials), and various clays, may be used as additives and / or carriers for the pesticide in the wall-forming material of the hollow core granules to make the granules buoyant. The controlled release options already discussed herein may also be applied to ensure that the pest control agent material is released at an appropriate time after application to the treatment site.

[0157] In exemplary embodiments, hollow-core pesticide granules can be prepared using a variety of wall-forming materials and a variety of binders. Clay (e.g., bentonite) can be particularly useful as a wall-forming material in pesticide granules, together with any specific solid pesticide material that may be contained in the granules. Similarly, clay can be useful as a carrier for one or more pesticides, which may typically be provided in liquid form. Suitable binders include hydrophilic materials, such as PEGs of various molecular weights (e.g., PEG8000, PEG12000, and / or PEG35000), or similar materials that dissolve immediately for the release of the pesticide material held in the granules. PEGs and similar binders may, in particular, have one or more pesticides mixed with them so that the binder functions as a vehicle for at least one portion of the pesticide material(s), and clay particles or similar materials may be used as essentially inert wall-forming agents.

[0158] In some embodiments, the products formed as hollow core structures described herein may be provided in unit dose form. As already mentioned above, a wide variety of materials may be used as wall-forming materials for the hollow core granules, and the resulting product may be a plurality of hollow core granules that can be provided in any desired mass or volume. However, in some embodiments, it may be beneficial to provide a combination of hollow core granules of a specified mass or volume to achieve a desired dosage. For example, in the field of detergents / cleaners, it may be desirable to provide a predetermined mass or volume of laundry detergent composition as a convenient pre-dosage for a single load of laundry. Similar advantages can be achieved in other fields such as nutritional supplements, fertilizers, and pesticides, and in further areas where it may be more convenient for consumers to have a pre-dosage hollow core granule product instead of measuring out the desired dose of individual granules. Accordingly, any one or more hollow core granule products according to this disclosure may be provided in unit dose format in addition to, or as an alternative to, mass supply of individual granules.

[0159] For example, granular detergent compositions and pastes, gels, slurries, etc., are known to be provided in water-soluble film pouches, which may be called pods. The compositions of the present invention, provided as hollow core granules, may similarly be provided in unit dose forms, such that a large quantity of hollow core granules is provided in a pouch of a predetermined weight and / or volume. Preferred techniques for providing hollow core granules as described in unit dose form are described, for example, in U.S. Patent No. 8,669,220 by Huber et al.; U.S. Patent Application Publication No. 2002 / 0033004 by Edwards et al.; U.S. Patent Application Publication No. 2007 / 0157572 by Oehms et al.; U.S. Patent Application Publication No. 2012 / 0097193 by Rossetto et al.; U.S. Patent No. 4,973,416 by Adamy et al.; and U.S. Patent Application Publication No. 7,915,213 by Kellar et al., all of which are incorporated herein by reference. In exemplary embodiments, hollow core granules providing a given product (e.g., laundry detergent, dish soap, fertilizer, pesticide, etc.) may be wrapped in a poly(vinyl alcohol) film using, for example, a simple Uline heat sealer, thereby forming a unit dose pod. Any suitable water-soluble film may be used, and any suitable sealing technique may be utilized to form pods in any desired mass / volume suitable for providing a specified amount of product for the desired end use. Unit doses may also be provided in other forms, such as fabric pouches which may be formed from soluble or non-soluble fibers.

[0160] Other types of unit dose forms are also covered by this disclosure. For example, a unit dose may comprise a large amount of solid compressed with one or more binders. Such unit dose forms may include the contents of hollow core granules described herein for a particular end use. For example, a product, e.g., a nutritional supplement, a chewable plaque-removing composition, or other product that is undesirable to be wrapped in a film, may be provided in such a format. In certain embodiments, a desired mass / volume of hollow core granules may be combined with a binder that allows multiple hollow core granules to be held together as a unit dose. For example, a gum (e.g., guar gum or xanthan gum), a cellulosic material, a starch material, and / or a water-soluble adhesive may be used to aggregate multiple hollow core granules into a single unit dose form, thereby producing such blocks, tablets, pills, caplets, prills, or other shape factors. These blocks etc. formed from the hollow core structure can be significantly lighter and / or significantly faster dissolved compared to known unit dose powders that do not contain the hollow core structure of the present invention.

[0161] In light of the improved absorption properties discussed earlier in this specification, hollow core granules can be particularly effective in forming one or more products for which absorption and / or adsorption of gases and / or liquids is desired. In some embodiments, hollow core granules may be configured for use in the absorption and / or adsorption of one or more air pollutants. Many substances are classified as air pollutants by, for example, the U.S. Environmental Protection Agency. Non-limiting examples of such substances include carbon monoxide, lead, nitrogen oxides, ozone, particulate matter, sulfur dioxide, acrolein, asbestos, benzene, carbon disulfide, creosote, fuel oil / kerosene, polycyclic aromatic hydrocarbons, synthetic glassy fibers, and total petroleum hydrocarbons. Many materials are similarly known to be effective in absorbing, adsorbing, or otherwise binding to one or more of these or other types of air pollutants. Such materials can be used as wall-forming materials when preparing hollow core granules according to this disclosure. Granules containing these air pollutant capturing components can be deployed in various forms for interaction with the surrounding air to capture one or more air pollutants. Similarly, the granules can be embedded in articles suitable for capturing and subsequently disposing of air pollutants, such as air filters, industrial pollutant capturing articles (e.g., power plant gas filters and exhaust cleaners), etc. Such granules may also be used in personal items, such as respiratory masks, to remove air pollutants for personal use. As a non-limiting example, activated carbon, zeolites, and other porous materials are known to be effective in capturing various pollutants, and such materials may be incorporated into hollow core granules as wall-forming materials, thus providing granules effective for capturing one or more pollutants and odors, etc.

[0162] In some embodiments, hollow core granules may be configured for use in absorbing or otherwise capturing liquids. Hollow core granules can be configured to have excellent liquid absorption properties, and may be configured to preferentially absorb aqueous or hydrophobic liquids, so that they can be used in various ways for liquid removal and / or remediation of liquid spill sites. In certain embodiments, hollow core granules can be configured to absorb one or more types of liquids without dissolving the granules themselves. In this way, the liquid can be bound by the granules, and thus may be removed as a substantially cohesive mass and / or as individual granules substantially retaining their granular structure. This can be particularly useful for removing organic spills (e.g., oil) in marine or other aquatic environments. Hollow core granules can be configured to float substantially on the water surface (e.g., exhibiting the buoyancy discussed earlier herein) to maximize interaction with the spilled organic matter. Here too, the hollow core granules can be configured to maintain their granular structure and / or aggregate into clumps that are relatively easy to remove once binding activity is complete. This can be extended to the preparation of single-component articles, such as spill sleeves, where the hollow core granules are retained within a fabric, mesh, or otherwise porous article to prevent the dispersion of individual granules across the water surface while still retaining the inflow of organic material. In some embodiments, the granules can also incorporate components that provide functions in addition to absorption and / or adsorption. For example, biological components are known to be useful in decomposing organic matter or making certain materials less viscous to improve the material's absorbability.

[0163] The hollow core granules disclosed herein can be readily formulated for desired end uses by selecting wall-forming materials and / or binder materials, as shown in the appended examples. For example, the use of a hydrophobic binder is shown herein to provide hollow core granules that float on the surface of water (i.e., exhibit buoyancy). On the other hand, the use of a hydrophilic binder, e.g., PEG, can provide hollow core granules that are hydrophilic and sink immediately in water and dissolve rapidly. Furthermore, the use of the same wall-forming material (e.g., bentonite) is shown herein to result in two different types of hollow core granules that behave similarly in both aqueous and non-aqueous environments, when used with a hydrophilic binder, e.g., PEG, or when used with a hydrophobic binder, e.g., paraffin. Thus, the selection of a very stable wall-forming material, e.g., bentonite, can determine the granule properties regardless of the binder selection. Furthermore, the granules can be further modified using coating materials to further adjust the properties. For example, a combination of a hydrophilic binder (e.g., PEG) and a very stable wall-forming material, such as bentonite, can generally produce hydrophilic granules. However, these granules can be modified by forming a hydrophobic coating layer to make them buoyant, thus enabling them to float in a water environment and perform design functions where buoyancy is desired. For example, hollow core granules formed from bentonite and PEG, but coated with a hydrophobic layer, such as paraffin, can be useful for cleaning up oil spills in marine environments. [Examples]

[0164] experiment This disclosure is more fully illustrated by the following embodiments, which are provided to illustrate specific embodiments of this disclosure and should not be construed as limiting this disclosure.

[0165] Experimental method Various samples of hollow core granules were prepared using a fluidized bed dryer. For each sample set, 5 grams of a selected binder in granular form with a selected particle size was loaded into the fluidized bed dryer along with 250 grams of a selected wall-forming material in granular form with a selected particle size. This resulted in an excess amount of wall-forming material necessary for the bonding required to form hollow core granules. After processing, the formed granules were removed from the fluidized bed dryer (leaving the remaining unbonded wall-forming material) and weighed. Since all of the loaded binder was used for granulation but not all of the wall-forming material particles were used, the binder concentration of the formed granules was calculated by dividing the total weight (grams) of the formed granules by 5 grams (the initial weight of the binder loaded). Granulation using 5 grams of binder and 250 grams of wall-forming material (sodium bicarbonate or bentonite clay in these examples) was typically effective in preparing approximately 50 grams of hollow core granules.

[0166] Granule and cavity size To measure the average size of the formed granules, the average size of the internal cavities (i.e., hollow cores), and the average wall thickness, 20 granules randomly selected from each test set were cut in half using an Exacto knife, and the half that was visually observed to better retain its original shape was microscopically measured using a microscope ruler. For granules exhibiting a substantially elongated shape, three measurements were taken for each dimension, and the average of the sum of the three measurements was recorded.

[0167] Granule density To measure the granule density, a cup with a known volume of 33.5 mL was filled with granules and weighed. The obtained weight was divided by the known volume to determine the granule density, and the bulk density was obtained as the average of five measurements for a given sample of granules.

[0168] Granule strength The granule strength was measured as the maximum force required to crush the granules. The test was performed using a Tinius Olsen Model 5 ST Benchtop Tester (5kN / 1klbf). The mechanical probe was set to move at a speed of 100 mm / min. Each measurement was repeated using 10 granules randomly selected from each set of granules. The resistance force was recorded, and the maximum peak force was taken as the strength value. The 10 measurements were averaged to obtain the final numerical value of the granule strength in a given batch.

[0169] water absorption To measure water absorption by granules, 1 gram of water was dropped onto a prepared layer of granules with an average thickness of 1 cm. This combination was allowed to stand for 5 minutes to form aggregates before weighing. The percentage of water absorption was calculated according to the following formula: [(weight of aggregate - 1 g) / 1 g] × 100%.

[0170] oil absorption To measure the absorption of oil by the granules, 8 grams of granules were placed in oil in a sieve for 5 minutes.

[0171] This combination was left for 5 minutes to drain off excess oil, and any remaining free oil was absorbed by the filter paper. Subsequently, the granules were weighed, and the percentage of oil absorption was calculated according to the following formula: [(Weight of wet granules - 8g) / 8g] × 100%.

[0172] Underwater stability To evaluate water stability, 3 grams of granules were placed in a beaker filled with 0.03 liters of water at room temperature (approximately 22°C). The granules were monitored to determine when they began to disintegrate. The time from when the granules were placed in the water-filled beaker until disintegration was measured and reported as the water stability time.

[0173] Stability in oil To evaluate oil stability, 3 grams of granules were placed in a beaker filled with 0.03 liters of Lukoil standard 10W-40 multigrade mineral engine oil (API SF / CC) at room temperature (approximately 22°C). The granules were monitored to determine when they began to disintegrate. The time from when the granules were placed in the oil-filled beaker until they disintegrated and appeared as a precipitate was measured and reported as the oil stability time.

[0174] buoyancy To evaluate the ability of granules to remain suspended in water, 3 grams of granules were placed in a beaker filled with 0.15 liters of water at room temperature (approximately 22°C). This combination was immediately evaluated, and in all cases where it was observed that the majority of the granules remained suspended, the granules were considered buoyant in water.

[0175] Dissolution time in agitated water To further evaluate solubility in water, 10 grams of granules were placed in a beaker filled with 1.4 liters of deionized water at room temperature (approximately 22°C). An impeller stirrer was placed in the beaker set to 500 rpm. The time from the addition of the granules until they disappeared (i.e., the solution became substantially clear, indicating substantial dissolution) was measured and reported as the dissolution time. Measurements were performed only for samples where the wall-forming material was a water-soluble solid (i.e., sodium bicarbonate).

[0176] Example 1: Sodium bicarbonate + PEG Granules were prepared using 5 grams of PEG8000 (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals, and this was loaded into a fluidized bed dryer with 250 grams of sodium bicarbonate (nominal size 0.100 mm to 0.400 mm). The fluidized bed dryer was operated at 65°C, and five batches were prepared at the maximum temperature with different residence times (5 minutes, 10 minutes, 15 minutes, 20 minutes, or 30 minutes). Each batch was cooled to 30°C before removing the formed granules. An image of one of the hollow core granules after cutting is shown in Figure 24.

[0177] The bulk density of granules as a function of processing time in the fluidized bed dryer was found to increase substantially with increasing residence time, and the measured values ​​are shown in Figure 5. Residence time was also found to be a factor in the total amount of sodium bicarbonate particles present in the formed granules, and the total content increased with processing time but appeared to plateau when the binder was fully utilized, as shown in Figure 6. Granule strength was found to remain almost constant, with only a slight decrease as processing time increased (see Figure 7). A similar pattern was observed with respect to particle abrasion (see Figures 8A-8E).

[0178] The size of the cavities in the formed granules was determined to be strongly influenced by the initial size of the binder particles. The shell thickness was approximately the same as the cavity diameter, as shown in Figure 9, where A, B, and C are the outer dimensions of the granules, and a, b, and c are the dimensions of the cavities. Therefore, it was found that the cavity diameter was approximately 1 / 3 of the outer diameter of the granules. Thus, the cavity volume was calculated to be approximately 3-4% of the total volume of the granules. The fractional composition of a typical batch of hollow core granules is shown in Figure 10, which was also found to depend on the residence time in the fluidized bed. The fractional composition was evaluated in accordance with ASTM E-11 using three sieves (nominal sizes of 1 mm, 2 mm, and 3.2 mm). In general, it was found that longer residence times in the fluidized bed resulted in larger granule sizes and longer time for the wall-forming material particles to aggregate with the binder crystals (see Figure 10). The overall granule characteristics are shown in the tables in Figures 17 and 18.

[0179] Example 2: Bentonite + PEG Granules were prepared using 5 grams of PEG8000 (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals, and these were loaded into a fluidized bed dryer together with 250 grams of bentonite (nominal size 0.100 mm to 0.400 mm). The fluidized bed dryer was operated at 65°C, and five batches were prepared at the maximum temperature with different residence times (15 minutes and 30 minutes). Each batch was cooled to 30°C before removing the formed granules. An image of one of the hollow core granules after cutting is shown in Figure 25.

[0180] The bulk density of the granules as a function of processing time in the fluidized bed dryer was found to substantially decrease with increasing residence time, and the measured values ​​are shown in Figure 11. The granule strength was found to be lower than the measured strength of the granules in Example 1 (the granules of the present invention were 3.6N, compared to 15N for the granules in Example 1). The shell thickness of the bentonite hollow core granules was approximately equal to the diameter of the cavity (see Figure 12). Therefore, the diameter of the cavity was found to be about 1 / 3 of the total diameter of the granules. Therefore, the volume of the cavity was found to be about 3-4% of the total volume of the granules (see Figure 13). The overall granule characteristics are shown in the tables in Figures 17 and 18.

[0181] Example 3: Sodium bicarbonate + bentonite + PEG Granules were prepared using 5 grams of PEG8000 (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals, and these were loaded into a fluidized bed dryer together with 235 grams of bentonite (nominal size 0.100 mm to 0.400 mm) and 235 grams of sodium bicarbonate (nominal size 0.100 mm to 0.400 mm). After operating the fluidized bed dryer at 65°C for 15 minutes, the mixture was cooled to 30°C, and the formed granules were removed. The obtained granules had an average granule size similar to that of the bentonite granules in Example 2. The density of the obtained granules was approximately intermediate between that of the sodium bicarbonate granules in Example 1 and the bentonite granules in Example 2. The strength of the granules was similar to that of the bentonite granules in Example 2. The overall granule characteristics are shown in the tables in Figures 17 and 18. Images of multiple hollow core granules are shown in Figure 26.

[0182] Example 4: Sodium bicarbonate + Brij(trademark) S100 Granules were prepared using 5 grams of Brij® S100 (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals, and loaded into a fluidized bed dryer with 250 grams of sodium bicarbonate (nominal size 0.100 mm to 0.400 mm). The fluidized bed dryer was operated at 60°C. Immediately after reaching the maximum temperature, the granules were cooled to 30°C, and the formed granules were removed (i.e., virtually zero residence time). Brij® S100 has a melting temperature similar to PEG8000, but the resulting liquid is much less viscous than liquefied PEG. This resulted in a remarkably fast processing rate, as the liquefied Brij® S100 penetrated the aggregated wall-forming particles, leaving cavities that partitioned the hollow core. The properties of the formed granules were substantially similar to those of PEG + sodium bicarbonate granules, except for the solubility parameter, because Brij™ S100 is somewhat more hydrophobic than PEG. The overall granule properties are shown in the tables in Figures 17 and 18. An image of one of the hollow core granules after cutting is shown in Figure 27.

[0183] Example 5: Bentonite + Brij(trademark) S100 Granules were prepared using 5 grams of Brij® S100 (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals, and loaded into a fluidized bed dryer together with 250 grams of bentonite (nominal size 0.100 mm to 0.400 mm). The fluidized bed dryer was operated at 60°C. Immediately after reaching the maximum temperature, the granules were cooled to 30°C, and the formed granules were removed (i.e., virtually zero residence time). The properties of the formed granules were substantially similar to those of PEG + bentonite granules. Brij® S100 + bentonite granules showed somewhat higher water stability because Brij® S100 is somewhat more hydrophobic than PEG. The overall granule properties are shown in the tables in Figures 17 and 18. An image of one of the hollow core granules after cutting is shown in Figure 28.

[0184] Example 6: Sodium bicarbonate + paraffin Granules were prepared using 5 grams of paraffin (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals, and this was loaded into a fluidized bed dryer along with 250 grams of sodium bicarbonate (nominal size 0.100 mm to 0.400 mm). The fluidized bed dryer was operated at 55°C with residence times of 0, 5, and 10 minutes at the maximum temperature. The formed granules were cooled to 30°C before removal. Since paraffin has a lower melting point than PEG, granule formation was faster than observed when PEG was used as the binder.

[0185] The bulk density of the formed granules was found to be lower than that of granules formed using wall-forming particles of sodium bicarbonate with either PEG8000 or Brij® S100 as a binder (i.e., 556–575 g / liter for the granules of the present invention compared to 671–716 g / liter for granules formed using PEG8000 or Brij® S100 as a binder). As can be seen in Figure 14, the overall granule size and cavity size were slightly smaller at a residence time of 0 minutes but increased with additional residence time in the fluidized bed. The volume of cavities was found to account for approximately 2–5% of the total granule volume (see Figure 15). These granules appeared to be relatively weaker than PEG-based granules, as demonstrated by both abrasion tests (see Figure 16) and crushing strength measurements (granules of the present invention with a strength of 3.5 N). The overall granule characteristics are shown in the tables in Figures 17 and 18.

[0186] Example 7: Bentonite + Paraffin Tests have shown that granules formed from bentonite and paraffin lack sufficient strength to withstand the slight shear forces encountered during preparation in the fluidized bed method described above. While we do not wish to be bound by theory, the hydrophilic nature of bentonite and the hydrophobic nature of paraffin are thought to be at least partially involved in the incompatibility that enables granule formation. However, the granules were prepared using a drum-like formation process. Granules were prepared using 5 grams of paraffin (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals. These were manually mixed with approximately 500 grams of bentonite (nominal size 0.100 mm to 0.400 mm) in a heated pan at 55°C for 5 minutes. After cooling to 30°C, the formed granules were removed for evaluation.

[0187] The strength of these granules was actually about 0.5 N (compared to about 3.5 N for samples prepared using PEG or Brig® S100). Due to the hydrophobic nature of paraffin, in the water absorption test, water did not propagate through the granular material but was absorbed into the bentonite particles on the surface, artificially inflating the measurement results in this method (115%). Most of the paraffin-bentonite granules initially floated in water but disintegrated in about 1 hour. The granules maintained their integrity in oil for longer than 3 days. The overall granule characteristics are shown in the tables in Figures 17 and 18.

[0188] Example 8: Bentonite + Stearic Acid Granules were reformed using a manual drum-like process with 5 grams of stearic acid (nominal size 1.2 mm to 1.6 mm) as binder particles or crystals. These were manually mixed with approximately 500 grams of bentonite (nominal size 0.100 mm to 0.400 mm) in a heated pan at 75°C for 5 minutes. After cooling to 30°C, the formed granules were removed for evaluation. Since sodium bicarbonate is known to decompose in the same temperature range as stearic acid (i.e., approximately 70°C), we did not attempt to test it using sodium bicarbonate as a wall-forming material. The strength and bulk density of the formed granules were similar to those obtained for granules made using paraffin and bentonite. In this case, stearic acid behaved as a hydrophobic binder very similar to paraffin. The overall granule properties are shown in the tables in Figures 17 and 18.

[0189] Example 9: Bentonite + Polycaprolactone Attempts were made to form hollow core granules using both the fluidized bed method and manual mixing methods described above, employing bentonite as the wall-forming material and polycaprolactone as the binder, but the hollow core granules were not successfully formed. Polycaprolactone is a hydrophobic polymer with a melting point of 60°C, and even when temperatures up to 150°C were used, the resulting product was a thin coating of bentonite particles surrounding a solid polycaprolactone core. While we do not wish to be bound by theory, it is thought that the viscosity of the liquefied polycaprolactone was too high, preventing the liquid from propagating into the bentonite shell. Therefore, it was determined that the viscosity of the liquefied binder should be sufficiently low to allow the wall-forming particles to propagate into the wall in order to successfully form hollow core granules. Similarly, higher viscosity materials, such as polycaprolactone, are also considered usable when mixed with another binder material and / or viscosity modifier so that the overall viscosity of the liquefied binder composition is sufficiently low for hollow granule formation.

[0190] Example 10: Formation of hollow core granules by hydrogel method Hydrogel particles were prepared using a 2.4 wt% aqueous solution of agar. This solution was heated to approximately 100°C to dissolve the agar, and then cooled to 60°C to maintain a suitable solution viscosity for further processing. Droplets were formed by injecting a stream of agar solution into a vegetable oil bath cooled to approximately 11°C. The droplets formed spontaneously upon contact with the vegetable oil. The formed droplets were then separated from the oil and washed with a soapy solution.

[0191] The separated and washed droplets were partially dried in air and then coated with a conditioning composition formed from talcum powder and silicone oil. The conditioned gel droplets were then mixed with bentonite powder until the particles were visually substantially uniformly coated with bentonite powder. The coated granules were dried under static heating at a temperature of approximately 120°C. The drying time was found to be partially dependent on the thickness of the granule layer. For example, a layer of substantially uniform thickness dried sufficiently in about 1 hour, while a granule layer of approximately 1 cm thickness required about 10 hours for the desired drying time. While static drying was used, forced air may be applied to shorten the drying time. Some samples were dried at a temperature of approximately 160°C, but such drying temperatures were found to result in undesirable shrinkage / deformation of the particles.

[0192] Example 11: Hollow core detergent granules Hollow core granules were prepared using a powdered detergent composition, and the changes in properties of the prepared hollow core granules were tested against the natural detergent powder. The detergent used was a commercially available composition sold under the name Arm and Hammer Crisp Clean Detergent. To prepare hollow core granules, Pluriol® E8000PEG particles were loaded into a Sherwood M501 fluidized bed dryer as a binder material along with powdered detergent as a wall-forming material, and the material was processed to form hollow core detergent granules. Three separate runs were performed to obtain three samples of hollow core detergent granules. In Examples 1-3, processing was carried out in the same manner as the preparation method described above to obtain "lab scale" granule formations in quantities of approximately 100 grams (test samples 1-3 discussed below). Two additional samples were prepared on a production scale to obtain granule formations in quantities of 4 kg (test sample 4) and 50 kg (test sample 5), confirming that the observed properties were consistently maintained in large-scale production.

[0193] Next, the solubility of the hollow-core detergent granules was compared to that of the detergent composition in its natural form (i.e., "neat"). For each test sample (hollow-core granules or neat detergent powder), 10 grams of the sample were dissolved in 1600 mL of water at room temperature, and the time it took for all the granules to dissolve was recorded as the dissolution time. A 2000 mL glass beaker was used for this test, and the mixture was stirred at 700 rpm using an IKA Werke EUROSTAR Power-B Overhead Stirrer Mixer equipped with a propeller. The time was measured using a stopwatch.

[0194] A comparative neat sample of detergent powder showed a dissolution time of 9 minutes and 32 seconds. Five test samples of hollow-core detergent granules showed the following dissolution times: 1) 4 minutes and 30 seconds; 2) 4 minutes and 24 seconds; 3) 4 minutes and 21 seconds; 4) 4 minutes and 37 seconds; and 5) 6 minutes and 11 seconds. As verified by the tests, the presentation of the detergent composition in hollow-core format significantly reduced the time to dissolution compared to its natural form. This was surprising, as the particle size of the powdered detergent composition did not change in the hollow-core form compared to the natural form. Rather, the dissolution time of the detergent composition in hollow-core form was reduced to an even shorter duration than the dissolution time of the binder material. This is considered evidence that the overall properties of hollow-core granules provide an additive effect or more in improving dissolution properties, and such a remarkable improvement in physical properties is expected to extend to other functions, such as absorption properties. Furthermore, the significant reduction in dissolution time supports the expectation that the presentation of other chemical products, compounds, and compositions in a hollow core format will improve the dissolution of such hollow core products, and proportionally improve the release of their components (e.g., cleaners, fertilizers, pesticides, and other materials discussed herein).

[0195] Example 12: Hollow core granule odor test Hollow core granules were prepared using various different wall-forming materials, and their ability to trap odor-causing chemicals and prevent or reduce associated odors was evaluated. A total of seven samples were evaluated: 1) Hollow core granules containing PEG binder and activated carbon as wall-forming materials; 2) Hollow core granules containing PEG binder and zeolite clinoptilolite as wall-forming materials; 3) Hollow core granules containing PEG binder and sepiolite clay as wall-forming materials; 4) Hollow core granules containing a mixture of PEG binder and sepiolite clay, zeolite clinoptilolite, and activated carbon as wall-forming materials; 5) Hollow core granules containing PEG binder and sodium bicarbonate as wall-forming materials; 6) Natural sodium bicarbonate powder; and 7) Natural sodium bentonite clay from Bentonite Performance Minerals. Samples 6 and 7 were used as comparison examples to compare the odor reduction performance of the hollow core granules with materials typically used in products, such as pet litter. For each of the hollow core granule samples 1 to 5, each sample was prepared to contain approximately 15% to 25% by weight of PEG binder and approximately 85% to 75% by weight of the respective wall-forming material. SEM images of the zeolite clinoptilolite hollow core granules are provided in Figures 19A and 19B. SEM images of the activated carbon hollow core granules are provided in Figures 20A and 20B. SEM images of the sodium bicarbonate hollow core granules are provided in Figures 21A to 21C.

[0196] To conduct the odor test, approximately 100 grams of test sample were placed in an Erlenmeyer vacuum flask equipped with a side valve and a single-hole stopper. Either an additional valve or a Drager ammonia sampling tube (available from Drager, Inc.) was attached to the stopper. Approximately 20 mL of synthetic urine (felinine (an amino acid compound [2-amino-3-propanoic acid] found in cat urine, and a microbial lyase-mediated precursor of the putative cat pheromone) and thiol [3-mercapto-3-methylbutan-1-ol]) was added to each sample. Ammonia levels were monitored directly from the Drager tube, and sulfur gas was periodically measured using a Halimeter (available from Interscan Corporation). The samples were monitored for approximately 100 hours, and NH3 (ppm) and S (ppb) were measured. The results showed that lower concentrations of each odor-causing chemical were associated with better performance of the test material in capturing the odor-causing chemical, while higher concentrations were associated with lower performance. Figure 22 shows the odor reduction performance using NH3, and Figure 23 shows the odor reduction performance using S. For both NH3 and S gas, the hollow-core zeolite clinoptilolite provided the best degree of odor reduction. As can be seen in Figure 23, a direct comparison between hollow-core sodium bicarbonate and natural sodium bicarbonate for sulfur odor reduction showed that the hollow-core material exhibited superior performance. Specifically, after approximately 100 hours, the S concentration measured for hollow-core sodium bicarbonate was approximately 26 ppb, while the S concentration measured for natural sodium bicarbonate was approximately 100 ppb.

[0197] As used herein, “about” or “substantially” may indicate that a particular enumerated value is intended to be interpreted as encompassing both the explicitly enumerated value and values ​​relatively close thereto. For example, a value “about” a particular number or “substantially” a particular value may refer not only to the particular number or value, but also to a number or value that varies from it by (+ or -) 5%, 4%, 3%, 2%, or 1% or less. In some embodiments, this value may be defined as a distinct value, and thus the terms “about” or “substantially” (and therefore the variance mentioned) may be excluded from such a distinct value.

[0198] Many modifications and other embodiments of the invention described herein will be recalled by those skilled in the art who are interested in these inventions and who have an interest in the teachings presented in the foregoing description. Therefore, it should be understood that the invention is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Certain terms are used herein, but they are used only in a general and descriptive sense and not for limiting purposes.

Claims

[Claim 1] Hollow core granules, A wall comprising a plurality of solid particles aggregated to have interstitial spaces between them, and the contents of a binder material present in at least a portion of the interstitial spaces, the wall having an outer surface and an inner surface, An internal cavity substantially enclosed by the aforementioned wall and whose boundary is defined by the aforementioned inner wall surface, the internal cavity not containing any internal mass that supports the wall so that the wall is structurally self-supporting, Includes, The melting point of the aforementioned binder material is approximately 40°C to approximately 95°C. The plurality of solid particles contain materials that are effective as components of detergent products or animal litter products. The aforementioned hollow core granules.

Images