Powder filling technology for aerosol canisters

Abstract

Three-phase aerosol canister filling process preventing particle agglomeration through powder-liquid separation. Commercial validation shows 611% improvement in statistical process control (Cpk 0.09 to 0.64) and controlled particle size maintenance (58 μm vs. 82 μm agglomeration in slurry methods) as demonstrated through scanning electron microscopy. Process includes environmental protection (inert gas blankets), precision equipment (antistatic coating, orbital welding), and achieves 6% material savings with elimination of consumer complaints acknowledged by major industry competitors. Enables manufacture of products meeting regulatory requirements that cannot be reliably produced using conventional slurry-based methods.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a continuation-in-part and claims priority from U.S. application Ser. No. 18 / 638,935, filed on Apr. 18, 2024, which claims priority to U.S. provisional application Ser. No. 63 / 498,612, filed Apr. 27, 2023, each herein incorporated by reference in their entireties.BACKGROUND

[0002] This invention relates to filling technology for aerosol canisters, and related processes and products.

[0003] Commercial data from 28,939 production units demonstrates that slurry methods produce systematic process control failures with capability index (Cpk) of about 0.09, far below industry standards. Conventional aerosol filling creates liquid-powder slurries before filling, causing particle agglomeration and product failures.

[0004] Scanning electron microscopy shows slurry processing increases PVP-I particle size from 38 to 82 microns (116% increase), causing actuator clogging in ICH Q7 stability studies. Major corporations acknowledge these problems: Unilever publicly stated “We've heard from our fans that your go-to Living Proof Dry Shampoo wasn't spraying properly. Trust us, we feel your pain.” (as stated on Unilever advertisement Jan. 30, 2025)

[0005] Slurry preparation requires expensive equipment ($400,000 mills), continuous agitation for 8-72 hours, and results in 10-13% material waste through required overfill to compensate for inconsistent delivery. These systematic failures indicate conventional methods are inadequate for reliable powder aerosol manufacturing.SUMMARY OF THE INVENTION

[0006] The present invention comprises a three-phase aerosol filling process that solves manufacturing failures through powder-liquid separation until point of filling. Commercial validation demonstrates about 611% improvement in statistical process control (Cpk about 0.09 to about 0.64), particle size control preventing agglomeration, and about 6% material cost savings.

[0007] The process comprises: Phase 1—adding a dry powder with environmental protection; Phase 2—adding a liquid without premature powder contact; Phase 3—adding a propellant. Specialized equipment includes inert gas blankets, precision dosing systems, and intrinsic safety features.

[0008] Head-to-head testing with identical formulations shows the process transforms statistically incapable manufacturing (Cpk 0.09) into approaching-capable operations (Cpk 0.64). BRIEFDESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a side view of an actuator for use in one embodiment.

[0010] FIG. 2 is a cross-sectional side view of a valve system for use in one embodiment.

[0011] FIG. 3A is a side view of an actuator for use in one embodiment; FIG. 3B is a cross-sectional view of the actuator taken along line A-A in FIG. 3A; FIG. 3C is an enlarged view of the actuator taken from circle X is FIG. 3B; and FIG. 3D is a table of the insert orifice measurements.

[0012] FIG. 4A is a cross-sectional view of a valve and valve components for use in one embodiment; FIG. 4B is an exploded view of the valve components in one embodiment; and FIG. 4C is a table listing the valve components.

[0013] FIG. 5A is a side view of a canister for use in one embodiment; and FIG. 5B is an enlarged view of section A from FIG. 5A of the cannister, according to one embodiment.

[0014] FIG. 6A is a SEM image of PVP-I raw powder (38 μm baseline).

[0015] FIG. 6B is a SEM image of PVP-I after slurry processing (82 μm, 116% agglomeration increase).

[0016] FIG. 6C is a SEM image of PVP-I after three-phase processing according to present invention (58 μm, controlled increase).DETAILED DESCRIPTION

[0017] The below discussion and definitions are intended to guide understanding but are not intended to be limiting with regard to other disclosures in this application. Throughout this application, references to percentage (%) of compositions of the present invention refers to the % by weight of a given substance to the total weight of the composition being discussed, also signified by “w / w” or “wt / wt”, unless stated otherwise.

[0018] Generally speaking, the present invention is directed to filling an aerosol canister without having to form a liquid-powder slurry prior to filling. The process of filling an aerosol canister without having to form a liquid-powder slurry prior to filling comprises at least 3 components (powder, liquid, and propellant) to be filled in three (3) distinct phases in an aerosol canister. In an embodiment, the present invention is directed to replacing the conventional, single-step process of filling a combination of powder and liquid components into a canister, with the present two-phase process of filling powder first and liquid after, or liquid first and powder after.

[0019] In an embodiment, a process of the present invention comprises, consists essentially of, or consists of at least the two-phase process described herein. In an embodiment, a product or aerosol composition of this invention comprises, consists essentially of, or consists of powder, liquid, and propellant of this invention.

[0020] In an embodiment of a process of this invention, Phase 1 is (i.e. comprises, consists essentially of, or consists of) the powder phase, during which powder is added to the aerosol canister (for instance free-flowing or non-free-flowing or amorphous or crystals or any form of solid); Phase 2 is (i.e. comprises, consists essentially of, or consists of) the liquid phase, during which liquid is added to the aerosol canister (where the liquid may be water based / solvent based, and may be a typical liquid and / or for instance an emulsion or paste); and Phase 3 is (i.e. comprises, consists essentially of, or consists of) the propellant phase, during which propellant (e.g. a propellant such as a compressed gas) is added to the aerosol canister to complete the filling of the canister and prepare a filled aerosol canister and a final aerosol product. The Phase 3 propellant phase occurs after Phase 2, and is not interchangeable with Phase 1 or Phase 2.

[0021] In an embodiment, Phase 1 is (i.e. comprises, consists essentially of, or consists of) the liquid phase, during which liquid is added to the aerosol canister (where the liquid may be water based / solvent based, and may be a typical liquid and / or for instance an emulsion or paste); Phase 2 is (i.e. comprises, consists essentially of, or consists of) the powder phase, during which powder is added to the aerosol canister (for instance free-flowing or non-free-flowing or amorphous or crystals or any form of solid); and Phase 3 is (i.e. comprises, consists essentially of, or consists of) the propellant phase, during which propellant (e.g. a propellant such as a compressed gas) is added to the aerosol canister to complete the filling of the canister and prepare a filled aerosol canister and a final aerosol product. The Phase 3 propellant phase occurs after Phase 2, and is not interchangeable with Phase 1 or Phase 2.

[0022] In an embodiment, powder filling technology, liquid filling technology, and / or propellant filling technology are / is conventional. In an embodiment, the present invention utilizes all three technologies (powder, liquid, and propellant) to create an aerosol spray with a heavy powder content. The conventional technology uses a slurry phase (powder and liquid premixed requiring continuous agitation and / or circulation) along with a propellant phase addition. The current invention utilizes powder, liquid, and propellant as separate phases which allows the powder to remain in powder format without any contact with liquid; in an embodiment said contact with liquid may reduce potency, efficiency, size, shape, and adsorbing or absorbing capabilities of the powder. The three phase filling technology also allows for ensuring all three phases of the correct proportions are added to the canister. In the event of the older technology using slurry, the powders (either suspended or solubilized) have a tendency to “fall out” resulting in incorrect, improper and / or inconsistent dosing amounts of the powder in the final canister.

[0023] In the present invention, in an embodiment and without being bound by theory, powder and liquid are not introduced to each other until the point of filling (i.e. added to the canister), preventing or minimizing particle agglomeration and preventing decreases in product efficacy. Without being bound by theory, by eliminating the interaction between the liquid and powder until filling, the powder is able to come into contact with the propellant more quickly and maintain its potency and useful structure.

[0024] The present invention provides several advantages over conventional aerosol filling technology. Significant advantages include improved finished product performance and improved product delivery, improved ease of handling, labor savings due to lower batching and compounding times and processes, lower capital expenses. Also, significant advantages include reduced batch time, reduced need for circulation, reduced risk of poor product, and improved effectiveness of the powder. Also, while a powder filler according to the present invention may require a capital expenditure of up to $200,000, such cost is roughly half the cost of powder mills that are needed for some current aerosol fillers, which may cost up to $400,000.

[0025] In an embodiment, a process of the present invention may be used in any aerosol canister filling process that requires or may require a powder load for instance in the liquid stage of the product, including for instance an aerosol canister that conventionally would be filled after dissolving or suspending the powder in a liquid for instance to form a slurry.

[0026] In an embodiment the powder added during the powder phase (Phase 1 or 2) is from about 0.1% to about 60% w / w of the liquid added during the liquid phase (Phase 1 or 2). In an embodiment the liquid added during the liquid phase (Phase 1 or 2) is from about 40% to about 99.9% w / w of the powder added during the powder phase (Phase 1 or 2).

[0027] In an embodiment of this invention, including a product or process, powder is from 1-25%, liquid is from 1-50%, and propellant is from 1-90%.

[0028] A “powder” e.g. as used in a Powder Phase according to the present invention, in an embodiment, comprises benzocaine, hydrocortisone, lidocaine, polyvinylpyrrolidone-iodine, colloidal oatmeal, aluminum chlorohydrate, aluminum chloride, aloe vera, pramoxide hydrochloride, tapioca starch, silica, rice starch, titanium oxide, zinc oxide, tolnaftate, miconazole nitrate, menthol, camphor, salicylic acid, cetylpyridinium chloride, budenoside, naloxone hydrochloride, phenylephrine, and / or any other active ingredient(s) or functional ingredient(s) or other ingredients that may exist in a powder or solid format. In an embodiment, a powder used in a Powder Phase of this invention comprises, consists of, or consists essentially of rice starch, cetrimonium chloride, kaolin, and distearyldimonium chloride. In an embodiment, a powder used in a Powder Phase of this invention comprises, consists of, or consists essentially of a mixture of corn starch, rice starch, and / or tapioca starch, benzothonium chloride, calamine powder, kaolin, sodium bicarbonate, and magnesium stearate. In an embodiment, the powder in the Powder Phase is about 5-15% w / w of the canister components, including e.g. 7-12% w / w, 7-10% w / w, or 8-12% w / w.

[0029] A “liquid” e.g. as used in a Liquid Phase according to the present invention in an embodiment of a product or process of the present invention can be any flowing liquid (i.e. that can be considered a liquid). For instance, in an embodiment, a liquid of this invention may be one or more of a solubilizing agent, suspending agent, and / or carrier. For instance, in an embodiment of this invention, a liquid may comprise alcohol(s), silicone(s), humectant(s), emollient(s), water, UVA / UVB agent(s), vegetable Oil(s), synthetic oil(s), and / or other flowing liquid(s) as discussed above. In an embodiment, a liquid used in a Liquid Phase of this invention comprises, consists essentially of, or consists of a mixture of ethanol, fragrance, extract(s), and silicone(s). In an embodiment, a liquid used in a Liquid Phase of this invention comprises, consists of, or consists essentially of a mixture of alcohol, silicone, sorbitan oleate, bisabolol, isopropylmyristate, fragrance, and essential oil(s). In an embodiment, the liquid in the Liquid Phase is about 2-20% w / w of the canister components, including e.g. 3-12% w / w, 3-6% w / w, or 8-12% w / w.

[0030] A “propellant” used in a Propellant Phase according to the present invention may be any propellant including e.g. a propelling chemical, e.g. a compressed gas, that may be filled into a canister and produce an aerosol. In an embodiment of a product or process of the present invention, propellant comprises any propellant or propelling chemical including but not limited to, in whole or partially, isobutane, butane, n-butane, propane, HFC 152a, 245fa, 1234ze, HFO-1234ze, 1233zd, HFO-1233zd, HFA134 a, HFA 134A / p, pentane, isopentane, nitrogen, compressed gas(es) such as compressed air, carbon dioxide, nitrogen dioxide, nitrous oxide, argon, and / or dimethyl ether, and / or any blend of any of the above or other propellants for instance, propellant mixture(s). A Propellant Phase of the present invention may include conventionally known or other processes for adding propellant to an aerosol canister, including for instance inline propellant blending. In an embodiment, a propellant used in a Propellant Phase of this invention comprises, consists of, or consists essentially of a mixture of propellants such as HFC 152a, propane, and isobutane. In an embodiment, the propellant in the Propellant Phase is about 75-90% w / w of the canister components, including e.g. 1-80%, 50-90%, 80-90%, or 75-85% w / w.

[0031] An “aerosol canister” according to the present invention refers to a canister that will have or has powder, liquid, and propellant under pressure to be dispensed as an aerosol. In an embodiment, the canister is a container that may be used to hold and dispense an aerosol. In an embodiment, an aerosol canister is a self-propelled canister. In an embodiment, an aerosol canister according to the present invention is through-the-valve, metered valve, under the cup, or is prepared with micro-filling technology.

[0032] In an embodiment, an aerosol canister product of the present invention comprises an aerosol canister of this invention having been filled with Phases 1, 2, and 3. Said aerosol product may include aerosol formulations inclusive of for instance topical, oral, and / or hair products, for instance for personal care; medical devices; over the counter; or any other aerosol products. A canister may be sized for a desired use, including for instance hand-held use.

[0033] An example of a canister of the present invention is shown in FIG. 5. Dimensions are presented in millimeters, unless otherwise stated. The canister is prepared with an aluminum alloy having 95% or more aluminum (e.g. 99.7%). The canister is lined with a phenolic epoxy. The canister provides a minimum of metal exposure (e.g. 50 mA maximum). The opening is 1″ outside. The canister has a pressure rating of DOT 2P, overflow of 259 mL, and unfilled / empty container weight.

[0034] In an embodiment, powder filling technology (e.g. equipment) according to this invention is or may be commercially available equipment, in an embodiment that was customized to include special filling nozzles that place powder directly into a canister such as a 1 inch canister opening without any powder deposit such as visible powder deposit on the chime of the canister. Additionally, in an embodiment, special coatings and augers were or may be customized to create accurate dosing for free-flowing powders and non-free flowing powders so the equipment can handle all powder technologies despite their flow or coagulating characteristics. In an embodiment, the equipment was or may be customized to make the unit intrinsically safe e.g. for operations around flammable powders and / or electrostatically charged powders.

[0035] FIG. 1 is a drawing of an actuator 100 for use in one embodiment, for instance for preparing a dry shampoo powder spray as described in Example 1. The actuator 100 includes a height A1, a top portion thickness A2, and a width A3. A1 is between about 15 and 17 mm, A2 is between about 5 and 7 mm, and A3 is between about 21 and 24 mm. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown may not be to scale. Drawing scale is in millimeters (mm). Actuator is nonmechanical break up actuator. Specifications: basic actuator made of polypropylene, insert (Blk. 0.035″ orifice×0.036″ land length) is acetal. (Summit Europe, The Netherlands).

[0036] FIG. 2 is a cross sectional view of a valve system 10 for use in one embodiment, for instance for preparing a dry shampoo powder spray as described in Example 1. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown are not to scale. The valve system comprises a stem 2 (1×0.025×0.349 Nat, material: acetal), a body 3 (0.062 RE 0.031 VT, material: nylon), a spring 4 (0.023, material: 302 stainless steel), a gasket 5 (0.050 BUNA Summit SV-77 / 92; material BUNA), a cup 6 (M.CUP EPT / LAMB CON RiNek, material: TINPLATE / POLYPRO), and a tube 7 all operable to function and maintain the valve system 10 (standard cut, material: LD polyethylene). Dimension ‘A’ refers to stem outer diameter, measurement about 4.03 mm, tolerance±0.04 mm. Dimension ‘B’ refers to stem to curl of cup, measurement about 6.48 mm, tolerance±0.38 mm. Dimension ‘C’ refers to cup height, measurement about 9.40 mm, ±0.13 mm. Dimension ‘D’ refers to cup width, measurement about 32.52 mm, tolerance±0.08 mm. Dimension ‘E’ refers to dip tube outer diameter, measurement about 4.32 mm, tolerance±0.05 mm. Dimension ‘F’ refers to pedestal diameter, measurement about 12.64 mm, tolerance±0.13 mm. FBOC length for dip-tube with tube straight: about 160 mm. For can size 45×178. (Summit Europe, The Netherlands).

[0037] FIG. 3A is a side view an actuator 200 for use in one embodiment, for instance for an anti-perspirant product. FIG. 3B shows the actuator 200 with the overcap 210. FIG. 3C shows the insert in the orifice of the actuator 200. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown may not be to scale. (Lindal Dispenser GmbH, Schönberg, Germany). FIG. 3D is a table of the insert orifice measurements.

[0038] FIG. 4A is a cross-sectional view of a valve 400 and valve components for use in one embodiment. Dimensions shown may be varied to accommodate equipment of different sizes.

[0039] Dimensions shown may not be to scale. FIG. 4B is an exploded view of the valve assembly 400 including the valve components A (mounting cup), B (mounting cup gasket), C (inner gasket), D (stem), E (spring), F (housing), G (diptube). (Lindal Group, Lindal North America, Columbus, Indiana). FIG. 4C is a table listing the valve components and component description.

[0040] FIG. 5A is a side view a canister 500 for use in one embodiment. FIG. 5B is an enlarged view of A from FIG. 5A, showing the radius of curvature at about 26.5. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown may not be to scale. Units shown are in millimeters (mm), unless otherwise stated. Canister description: Aluminum Alloy (99.7% A1, 1070), white exterior, round shoulder, epoxyphenolic inside liner, maximum metal exposure: 50.0 mA, 1″ outside opening, pressure rating: DOT 2P, weight: 28 g (ref), overflow: 259 mL (ref), machine curl.

[0041] The present invention comprises a three-phase filling process validated through extensive commercial manufacturing. Process control improvements are demonstrated through head-to-head comparison using identical MICRO-DRY 323 aluminum chlorohydrate formulations.

[0042] The Process Capability Index (Cpk) is a statistical measure in quality control showing how well a process meets customer specifications, indicating both its consistency (narrow spread) and its centering (mean close to the target) relative to specification limits (USL / LSL). A higher Cpk signifies a better, more capable process, while a lower Cpk suggests potential nonconforming product.TABLE 1Head-to-Head Manufacturing ComparisonConventional Three-ParameterSlurryPhase ProcessImprovementSample Size28,939 units5,410 unitsStatisticallysignificantProcess 0.090.64611%Capability(INCAPABLE)(APPROACHING)IMPROVEMENT(Cpk)Standard 0.83%0.46%44% reductionDeviationPVP-I Particle 82 μm (+116%)58 μm (+53%)ControlledSizeagglomerationThree-Phase Process Specifications:Phase 1—Powder Phase: Dry powder addition with inert gas protection (nitrogen, argon, helium) preventing hygroscopic powder moisture absorption. Pre-measured dosing ensures consistent delivery.Phase 2—Liquid Phase: Liquid addition with process enhancements: about 35° C. heating for aluminum chlorohydrate systems, nitrogen purge for anhydrous conditions.

[0045] Phase 3—Propellant Phase: Propellant addition with precision nozzles preventing powder deposit on canister chime, ensuring proper valve sealing.

[0046] Scanning electron microscopy shows conventional slurry processing increases PVP-I particle size from 38 to 82 microns (116% increase), causing actuator clogging in ICH Q7 stability studies, as shown in FIGS. 6A-6B. Major corporations acknowledge these problems: Unilever publicly stated “We've heard from our fans that your go-to Living Proof Dry Shampoo wasn't spraying properly. Trust us, we feel your pain.” (as stated by Unilever on Jan. 30, 2025.

[0047] FIG. 6A is a SEM image of PVP-I raw powder (about 38 μm baseline).

[0048] FIG. 6B is a SEM image of PVP-I after slurry processing (about 82 μm, about 116% agglomeration increase).

[0049] FIG. 6C is a SEM image of PVP-I after three-phase processing according to the present invention (about 58 μm, controlled increase).Equipment Specifications:

[0050] Specialized powder filling equipment includes: antistatic coating preventing powder adhesion; orbital welding eliminating accumulation crevices; stainless steel mirror polish (Ra<0.4 μm) for smooth flow; intrinsically safe design with mechanical powder contact zone separated from electrical components; chime-protection nozzles preventing valve failures.Evidence SummaryUnexpected Results: about an 611% Cpk improvement (about 0.09→about 0.64); Particle size control (about 38 μm→about 58 μm vs. about 82 μm slurry); Process time reduction (between about 8 to about 72 hours→2 about hours), as shown in FIGS. 6B-6C.

[0052] Industry Recognition: Unilever acknowledgment of unsolved problems; $60+ billion corporation couldn't solve with conventional methods; Public admission of product failures

[0053] Commercial Success: Three successful product lines; ICH Q7 stability compliance; about a 6% material cost savings; Zero consumer complaints.

[0054] The present invention may be further understood in connection with the following Examples and embodiments. The following non-limiting Examples and also embodiments described throughout this application are provided to illustrate the invention.EXAMPLES

[0055] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices and / or methods claimed herein are made and evaluated, and are intended to be purely exemplary of the invention and are not intended to limit the scope of what the inventors regard as their invention. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

[0056] Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in ° C. or is at ambient temperature, and pressure is at or near atmospheric.Example 1: Dry Shampoo Powder Spray

[0057] A dry shampoo powder spray is prepared according to the following 3 Phases:Phase 1Phase 2Phase 3Mixture of Rice Starch,Mixture of Ethanol,Propellant or mixture ofCetrimonium Chloride,fragrance, extracts, siliconespropellants-HFC152A,Kaolin, DistearyldimoniumIsobutane, PropaneChloride~7-~10% w / w~3-~6% w / w~80-~90% w / wExample 2: Anti-Chafing Spray

[0058] An anti-chafing spray is prepared according to the following 3 Phases:Phase 1-Powder blendPhase 2-Liquid blendPhase 3-Propellant blendMixture of Corn / Rice / Mixture of alcohol, silicone,Mixture of propellants-HFCTapioca Starch,sorbitan oleate, bisabolol,152a, propane, isobutaneBenzothonium Chloride,isopropylmyristate, fragrance,Calamine Powder, Kaolin,essential oilsSodium Bicarbonate,Magnesium Stearateabout 8-abount 12% w / wabout 8-about 12% w / wabout 75-about 85% w / w

[0059] The powder filling equipment is a commercially available equipment that was customized to include special filling nozzles that place powder directly into the 1-inch canister opening without any powder deposit on the chime of the canister. Additionally, special coatings and augers were customized to create accurate dosing for free-flowing powders and non-free flowing powders so the equipment can handle all powder technologies despite their flow or coagulating characteristics. Additionally, the equipment was customized to make the unit intrinsically safe for operations around flammable powders and / or electrostatically charged powders.Example 3: Dry Shampoo Powder SprayPhase 1: Rice Starch, Cetrimonium Chloride, Kaolin, Distearyldimonium Chloride (between about 7-about 10% w / w);

[0061] Phase 2: Ethanol, fragrance, extracts, silicones (between about 3-about 6% w / w);

[0062] Phase 3: HFC152A, Isobutane, Propane (between about 80-about 90% w / w).

[0063] Results: Elimination of consumer complaints (Unilever acknowledgment proves industry problem), about 6% material savings through reduced overfill (between about 116-about 120 g vs. between about 122-about 127 g), resolution of hygroscopic powder handling challenges.Example 4: Antiperspirant SprayPhase 1: Aluminum Chlorohydrate (MICRO-DRY 323), starches, other powders (between about 10-about 14% w / w);

[0065] Phase 2: Alcohol, silicone, carriers—heated to about 35° C. with nitrogen purge (remainder); and

[0066] Phase 3: HFC 152a, propane, isobutane (between about 55-about 70% w / w).

[0067] Results: Head-to-head comparison with identical formulations: Cpk improvement from about 0.09 to about 0.64 (about 611% increase), mean API about 19.42% to about 20.08% (closer to about 20.20% target), standard deviation reduced about 44%, process time reduced from between about 8-about 72 hours to about 2 hours.Example 5: PVP-I Antiseptic SprayPhase 1: Povidone-Iodine Complex powder (between about 4-about 8% w / w);

[0069] Phase 2: Isopropyl Myristate liquid carrier (between about 3-about 7% w / w); and

[0070] Phase 3: N-Pentane, Propane / Butane propellant blend (between about 85-about 93% w / w).

[0071] SEM Analysis Results: —Raw powder: 38 μm average (baseline) —Slurry processing: about 82 μm average (about 116% agglomeration increase) —Three-phase processing: about 58 μm average (about 53% controlled increase), as shown in FIG. 6C.

[0072] Results: Zero actuator clogging in ICH Q7 stability studies vs. systematic slurry failures, particle size control enabling regulatory compliance, consistent API potency delivery.

[0073] The use of the terms “a,”“an,”“the,” and similar referents in the context of describing the present invention (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0074] Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. Use of the term “about” is intended to describe values either above or below the stated value in a range of approximately ±10%; in other embodiments, the values may range in value above or below the stated value in a range of approximately ±5%; in other embodiments, the values may range in value above or below the stated value in a range of approximately ±2%; in other embodiments, the values may range in value above or below the stated value in a range of approximately ±1%. The preceding ranges are intended to be made clear by context, and no further limitation is implied. All method steps described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise stated. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0075] As used herein the term “method” refers to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the chemical, mechanical, biochemical and medical arts. Unless otherwise expressly stated, it is in no way intended that any method or aspect set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not specifically state in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including matters of logic with respect to arrangement of steps or operational flow, plain meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification.

[0076] While in the foregoing specification the present invention has been described in relation to certain embodiments thereof, and many details have been put forth for the purposes of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of the invention.

[0077] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.

Examples

example 1

Dry Shampoo Powder Spray

[0057]A dry shampoo powder spray is prepared according to the following 3 Phases:

Phase 1Phase 2Phase 3Mixture of Rice Starch,Mixture of Ethanol,Propellant or mixture ofCetrimonium Chloride,fragrance, extracts, siliconespropellants-HFC152A,Kaolin, DistearyldimoniumIsobutane, PropaneChloride~7-~10% w / w~3-~6% w / w~80-~90% w / w

example 2

Anti-Chafing Spray

[0058]An anti-chafing spray is prepared according to the following 3 Phases:

Phase 1-Powder blendPhase 2-Liquid blendPhase 3-Propellant blendMixture of Corn / Rice / Mixture of alcohol, silicone,Mixture of propellants-HFCTapioca Starch,sorbitan oleate, bisabolol,152a, propane, isobutaneBenzothonium Chloride,isopropylmyristate, fragrance,Calamine Powder, Kaolin,essential oilsSodium Bicarbonate,Magnesium Stearateabout 8-abount 12% w / wabout 8-about 12% w / wabout 75-about 85% w / w

[0059]The powder filling equipment is a commercially available equipment that was customized to include special filling nozzles that place powder directly into the 1-inch canister opening without any powder deposit on the chime of the canister. Additionally, special coatings and augers were customized to create accurate dosing for free-flowing powders and non-free flowing powders so the equipment can handle all powder technologies despite their flow or coagulating characteristics. Additionally, the e...

example 3

Dry Shampoo Powder Spray

Phase 1: Rice Starch, Cetrimonium Chloride, Kaolin, Distearyldimonium Chloride (between about 7-about 10% w / w);[0061]Phase 2: Ethanol, fragrance, extracts, silicones (between about 3-about 6% w / w);[0062]Phase 3: HFC152A, Isobutane, Propane (between about 80-about 90% w / w).[0063]Results: Elimination of consumer complaints (Unilever acknowledgment proves industry problem), about 6% material savings through reduced overfill (between about 116-about 120 g vs. between about 122-about 127 g), resolution of hygroscopic powder handling challenges.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a continuation-in-part and claims priority from U.S. application Ser. No. 18 / 638,935, filed on Apr. 18, 2024, which claims priority to U.S. provisional application Ser. No. 63 / 498,612, filed Apr. 27, 2023, each herein incorporated by reference in their entireties.BACKGROUND

[0002] This invention relates to filling technology for aerosol canisters, and related processes and products.

[0003] Commercial data from 28,939 production units demonstrates that slurry methods produce systematic process control failures with capability index (Cpk) of about 0.09, far below industry standards. Conventional aerosol filling creates liquid-powder slurries before filling, causing particle agglomeration and product failures.

[0004] Scanning electron microscopy shows slurry processing increases PVP-I particle size from 38 to 82 microns (116% increase), causing actuator clogging in ICH Q7 stability studies. Major corporations acknowledge these problems: Unilever publicly stated “We've heard from our fans that your go-to Living Proof Dry Shampoo wasn't spraying properly. Trust us, we feel your pain.” (as stated on Unilever advertisement Jan. 30, 2025)

[0005] Slurry preparation requires expensive equipment ($400,000 mills), continuous agitation for 8-72 hours, and results in 10-13% material waste through required overfill to compensate for inconsistent delivery. These systematic failures indicate conventional methods are inadequate for reliable powder aerosol manufacturing.SUMMARY OF THE INVENTION

[0006] The present invention comprises a three-phase aerosol filling process that solves manufacturing failures through powder-liquid separation until point of filling. Commercial validation demonstrates about 611% improvement in statistical process control (Cpk about 0.09 to about 0.64), particle size control preventing agglomeration, and about 6% material cost savings.

[0007] The process comprises: Phase 1—adding a dry powder with environmental protection; Phase 2—adding a liquid without premature powder contact; Phase 3—adding a propellant. Specialized equipment includes inert gas blankets, precision dosing systems, and intrinsic safety features.

[0008] Head-to-head testing with identical formulations shows the process transforms statistically incapable manufacturing (Cpk 0.09) into approaching-capable operations (Cpk 0.64). BRIEFDESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 is a side view of an actuator for use in one embodiment.

[0010] FIG. 2 is a cross-sectional side view of a valve system for use in one embodiment.

[0011] FIG. 3A is a side view of an actuator for use in one embodiment; FIG. 3B is a cross-sectional view of the actuator taken along line A-A in FIG. 3A; FIG. 3C is an enlarged view of the actuator taken from circle X is FIG. 3B; and FIG. 3D is a table of the insert orifice measurements.

[0012] FIG. 4A is a cross-sectional view of a valve and valve components for use in one embodiment; FIG. 4B is an exploded view of the valve components in one embodiment; and FIG. 4C is a table listing the valve components.

[0013] FIG. 5A is a side view of a canister for use in one embodiment; and FIG. 5B is an enlarged view of section A from FIG. 5A of the cannister, according to one embodiment.

[0014] FIG. 6A is a SEM image of PVP-I raw powder (38 μm baseline).

[0015] FIG. 6B is a SEM image of PVP-I after slurry processing (82 μm, 116% agglomeration increase).

[0016] FIG. 6C is a SEM image of PVP-I after three-phase processing according to present invention (58 μm, controlled increase).DETAILED DESCRIPTION

[0017] The below discussion and definitions are intended to guide understanding but are not intended to be limiting with regard to other disclosures in this application. Throughout this application, references to percentage (%) of compositions of the present invention refers to the % by weight of a given substance to the total weight of the composition being discussed, also signified by “w / w” or “wt / wt”, unless stated otherwise.

[0018] Generally speaking, the present invention is directed to filling an aerosol canister without having to form a liquid-powder slurry prior to filling. The process of filling an aerosol canister without having to form a liquid-powder slurry prior to filling comprises at least 3 components (powder, liquid, and propellant) to be filled in three (3) distinct phases in an aerosol canister. In an embodiment, the present invention is directed to replacing the conventional, single-step process of filling a combination of powder and liquid components into a canister, with the present two-phase process of filling powder first and liquid after, or liquid first and powder after.

[0019] In an embodiment, a process of the present invention comprises, consists essentially of, or consists of at least the two-phase process described herein. In an embodiment, a product or aerosol composition of this invention comprises, consists essentially of, or consists of powder, liquid, and propellant of this invention.

[0020] In an embodiment of a process of this invention, Phase 1 is (i.e. comprises, consists essentially of, or consists of) the powder phase, during which powder is added to the aerosol canister (for instance free-flowing or non-free-flowing or amorphous or crystals or any form of solid); Phase 2 is (i.e. comprises, consists essentially of, or consists of) the liquid phase, during which liquid is added to the aerosol canister (where the liquid may be water based / solvent based, and may be a typical liquid and / or for instance an emulsion or paste); and Phase 3 is (i.e. comprises, consists essentially of, or consists of) the propellant phase, during which propellant (e.g. a propellant such as a compressed gas) is added to the aerosol canister to complete the filling of the canister and prepare a filled aerosol canister and a final aerosol product. The Phase 3 propellant phase occurs after Phase 2, and is not interchangeable with Phase 1 or Phase 2.

[0021] In an embodiment, Phase 1 is (i.e. comprises, consists essentially of, or consists of) the liquid phase, during which liquid is added to the aerosol canister (where the liquid may be water based / solvent based, and may be a typical liquid and / or for instance an emulsion or paste); Phase 2 is (i.e. comprises, consists essentially of, or consists of) the powder phase, during which powder is added to the aerosol canister (for instance free-flowing or non-free-flowing or amorphous or crystals or any form of solid); and Phase 3 is (i.e. comprises, consists essentially of, or consists of) the propellant phase, during which propellant (e.g. a propellant such as a compressed gas) is added to the aerosol canister to complete the filling of the canister and prepare a filled aerosol canister and a final aerosol product. The Phase 3 propellant phase occurs after Phase 2, and is not interchangeable with Phase 1 or Phase 2.

[0022] In an embodiment, powder filling technology, liquid filling technology, and / or propellant filling technology are / is conventional. In an embodiment, the present invention utilizes all three technologies (powder, liquid, and propellant) to create an aerosol spray with a heavy powder content. The conventional technology uses a slurry phase (powder and liquid premixed requiring continuous agitation and / or circulation) along with a propellant phase addition. The current invention utilizes powder, liquid, and propellant as separate phases which allows the powder to remain in powder format without any contact with liquid; in an embodiment said contact with liquid may reduce potency, efficiency, size, shape, and adsorbing or absorbing capabilities of the powder. The three phase filling technology also allows for ensuring all three phases of the correct proportions are added to the canister. In the event of the older technology using slurry, the powders (either suspended or solubilized) have a tendency to “fall out” resulting in incorrect, improper and / or inconsistent dosing amounts of the powder in the final canister.

[0023] In the present invention, in an embodiment and without being bound by theory, powder and liquid are not introduced to each other until the point of filling (i.e. added to the canister), preventing or minimizing particle agglomeration and preventing decreases in product efficacy. Without being bound by theory, by eliminating the interaction between the liquid and powder until filling, the powder is able to come into contact with the propellant more quickly and maintain its potency and useful structure.

[0024] The present invention provides several advantages over conventional aerosol filling technology. Significant advantages include improved finished product performance and improved product delivery, improved ease of handling, labor savings due to lower batching and compounding times and processes, lower capital expenses. Also, significant advantages include reduced batch time, reduced need for circulation, reduced risk of poor product, and improved effectiveness of the powder. Also, while a powder filler according to the present invention may require a capital expenditure of up to $200,000, such cost is roughly half the cost of powder mills that are needed for some current aerosol fillers, which may cost up to $400,000.

[0025] In an embodiment, a process of the present invention may be used in any aerosol canister filling process that requires or may require a powder load for instance in the liquid stage of the product, including for instance an aerosol canister that conventionally would be filled after dissolving or suspending the powder in a liquid for instance to form a slurry.

[0026] In an embodiment the powder added during the powder phase (Phase 1 or 2) is from about 0.1% to about 60% w / w of the liquid added during the liquid phase (Phase 1 or 2). In an embodiment the liquid added during the liquid phase (Phase 1 or 2) is from about 40% to about 99.9% w / w of the powder added during the powder phase (Phase 1 or 2).

[0027] In an embodiment of this invention, including a product or process, powder is from 1-25%, liquid is from 1-50%, and propellant is from 1-90%.

[0028] A “powder” e.g. as used in a Powder Phase according to the present invention, in an embodiment, comprises benzocaine, hydrocortisone, lidocaine, polyvinylpyrrolidone-iodine, colloidal oatmeal, aluminum chlorohydrate, aluminum chloride, aloe vera, pramoxide hydrochloride, tapioca starch, silica, rice starch, titanium oxide, zinc oxide, tolnaftate, miconazole nitrate, menthol, camphor, salicylic acid, cetylpyridinium chloride, budenoside, naloxone hydrochloride, phenylephrine, and / or any other active ingredient(s) or functional ingredient(s) or other ingredients that may exist in a powder or solid format. In an embodiment, a powder used in a Powder Phase of this invention comprises, consists of, or consists essentially of rice starch, cetrimonium chloride, kaolin, and distearyldimonium chloride. In an embodiment, a powder used in a Powder Phase of this invention comprises, consists of, or consists essentially of a mixture of corn starch, rice starch, and / or tapioca starch, benzothonium chloride, calamine powder, kaolin, sodium bicarbonate, and magnesium stearate. In an embodiment, the powder in the Powder Phase is about 5-15% w / w of the canister components, including e.g. 7-12% w / w, 7-10% w / w, or 8-12% w / w.

[0029] A “liquid” e.g. as used in a Liquid Phase according to the present invention in an embodiment of a product or process of the present invention can be any flowing liquid (i.e. that can be considered a liquid). For instance, in an embodiment, a liquid of this invention may be one or more of a solubilizing agent, suspending agent, and / or carrier. For instance, in an embodiment of this invention, a liquid may comprise alcohol(s), silicone(s), humectant(s), emollient(s), water, UVA / UVB agent(s), vegetable Oil(s), synthetic oil(s), and / or other flowing liquid(s) as discussed above. In an embodiment, a liquid used in a Liquid Phase of this invention comprises, consists essentially of, or consists of a mixture of ethanol, fragrance, extract(s), and silicone(s). In an embodiment, a liquid used in a Liquid Phase of this invention comprises, consists of, or consists essentially of a mixture of alcohol, silicone, sorbitan oleate, bisabolol, isopropylmyristate, fragrance, and essential oil(s). In an embodiment, the liquid in the Liquid Phase is about 2-20% w / w of the canister components, including e.g. 3-12% w / w, 3-6% w / w, or 8-12% w / w.

[0030] A “propellant” used in a Propellant Phase according to the present invention may be any propellant including e.g. a propelling chemical, e.g. a compressed gas, that may be filled into a canister and produce an aerosol. In an embodiment of a product or process of the present invention, propellant comprises any propellant or propelling chemical including but not limited to, in whole or partially, isobutane, butane, n-butane, propane, HFC 152a, 245fa, 1234ze, HFO-1234ze, 1233zd, HFO-1233zd, HFA134 a, HFA 134A / p, pentane, isopentane, nitrogen, compressed gas(es) such as compressed air, carbon dioxide, nitrogen dioxide, nitrous oxide, argon, and / or dimethyl ether, and / or any blend of any of the above or other propellants for instance, propellant mixture(s). A Propellant Phase of the present invention may include conventionally known or other processes for adding propellant to an aerosol canister, including for instance inline propellant blending. In an embodiment, a propellant used in a Propellant Phase of this invention comprises, consists of, or consists essentially of a mixture of propellants such as HFC 152a, propane, and isobutane. In an embodiment, the propellant in the Propellant Phase is about 75-90% w / w of the canister components, including e.g. 1-80%, 50-90%, 80-90%, or 75-85% w / w.

[0031] An “aerosol canister” according to the present invention refers to a canister that will have or has powder, liquid, and propellant under pressure to be dispensed as an aerosol. In an embodiment, the canister is a container that may be used to hold and dispense an aerosol. In an embodiment, an aerosol canister is a self-propelled canister. In an embodiment, an aerosol canister according to the present invention is through-the-valve, metered valve, under the cup, or is prepared with micro-filling technology.

[0032] In an embodiment, an aerosol canister product of the present invention comprises an aerosol canister of this invention having been filled with Phases 1, 2, and 3. Said aerosol product may include aerosol formulations inclusive of for instance topical, oral, and / or hair products, for instance for personal care; medical devices; over the counter; or any other aerosol products. A canister may be sized for a desired use, including for instance hand-held use.

[0033] An example of a canister of the present invention is shown in FIG. 5. Dimensions are presented in millimeters, unless otherwise stated. The canister is prepared with an aluminum alloy having 95% or more aluminum (e.g. 99.7%). The canister is lined with a phenolic epoxy. The canister provides a minimum of metal exposure (e.g. 50 mA maximum). The opening is 1″ outside. The canister has a pressure rating of DOT 2P, overflow of 259 mL, and unfilled / empty container weight.

[0034] In an embodiment, powder filling technology (e.g. equipment) according to this invention is or may be commercially available equipment, in an embodiment that was customized to include special filling nozzles that place powder directly into a canister such as a 1 inch canister opening without any powder deposit such as visible powder deposit on the chime of the canister. Additionally, in an embodiment, special coatings and augers were or may be customized to create accurate dosing for free-flowing powders and non-free flowing powders so the equipment can handle all powder technologies despite their flow or coagulating characteristics. In an embodiment, the equipment was or may be customized to make the unit intrinsically safe e.g. for operations around flammable powders and / or electrostatically charged powders.

[0035] FIG. 1 is a drawing of an actuator 100 for use in one embodiment, for instance for preparing a dry shampoo powder spray as described in Example 1. The actuator 100 includes a height A1, a top portion thickness A2, and a width A3. A1 is between about 15 and 17 mm, A2 is between about 5 and 7 mm, and A3 is between about 21 and 24 mm. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown may not be to scale. Drawing scale is in millimeters (mm). Actuator is nonmechanical break up actuator. Specifications: basic actuator made of polypropylene, insert (Blk. 0.035″ orifice×0.036″ land length) is acetal. (Summit Europe, The Netherlands).

[0036] FIG. 2 is a cross sectional view of a valve system 10 for use in one embodiment, for instance for preparing a dry shampoo powder spray as described in Example 1. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown are not to scale. The valve system comprises a stem 2 (1×0.025×0.349 Nat, material: acetal), a body 3 (0.062 RE 0.031 VT, material: nylon), a spring 4 (0.023, material: 302 stainless steel), a gasket 5 (0.050 BUNA Summit SV-77 / 92; material BUNA), a cup 6 (M.CUP EPT / LAMB CON RiNek, material: TINPLATE / POLYPRO), and a tube 7 all operable to function and maintain the valve system 10 (standard cut, material: LD polyethylene). Dimension ‘A’ refers to stem outer diameter, measurement about 4.03 mm, tolerance±0.04 mm. Dimension ‘B’ refers to stem to curl of cup, measurement about 6.48 mm, tolerance±0.38 mm. Dimension ‘C’ refers to cup height, measurement about 9.40 mm, ±0.13 mm. Dimension ‘D’ refers to cup width, measurement about 32.52 mm, tolerance±0.08 mm. Dimension ‘E’ refers to dip tube outer diameter, measurement about 4.32 mm, tolerance±0.05 mm. Dimension ‘F’ refers to pedestal diameter, measurement about 12.64 mm, tolerance±0.13 mm. FBOC length for dip-tube with tube straight: about 160 mm. For can size 45×178. (Summit Europe, The Netherlands).

[0037] FIG. 3A is a side view an actuator 200 for use in one embodiment, for instance for an anti-perspirant product. FIG. 3B shows the actuator 200 with the overcap 210. FIG. 3C shows the insert in the orifice of the actuator 200. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown may not be to scale. (Lindal Dispenser GmbH, Schönberg, Germany). FIG. 3D is a table of the insert orifice measurements.

[0038] FIG. 4A is a cross-sectional view of a valve 400 and valve components for use in one embodiment. Dimensions shown may be varied to accommodate equipment of different sizes.

[0039] Dimensions shown may not be to scale. FIG. 4B is an exploded view of the valve assembly 400 including the valve components A (mounting cup), B (mounting cup gasket), C (inner gasket), D (stem), E (spring), F (housing), G (diptube). (Lindal Group, Lindal North America, Columbus, Indiana). FIG. 4C is a table listing the valve components and component description.

[0040] FIG. 5A is a side view a canister 500 for use in one embodiment. FIG. 5B is an enlarged view of A from FIG. 5A, showing the radius of curvature at about 26.5. Dimensions shown may be varied to accommodate equipment of different sizes. Dimensions shown may not be to scale. Units shown are in millimeters (mm), unless otherwise stated. Canister description: Aluminum Alloy (99.7% A1, 1070), white exterior, round shoulder, epoxyphenolic inside liner, maximum metal exposure: 50.0 mA, 1″ outside opening, pressure rating: DOT 2P, weight: 28 g (ref), overflow: 259 mL (ref), machine curl.

[0041] The present invention comprises a three-phase filling process validated through extensive commercial manufacturing. Process control improvements are demonstrated through head-to-head comparison using identical MICRO-DRY 323 aluminum chlorohydrate formulations.

[0042] The Process Capability Index (Cpk) is a statistical measure in quality control showing how well a process meets customer specifications, indicating both its consistency (narrow spread) and its centering (mean close to the target) relative to specification limits (USL / LSL). A higher Cpk signifies a better, more capable process, while a lower Cpk suggests potential nonconforming product.TABLE 1Head-to-Head Manufacturing ComparisonConventional Three-ParameterSlurryPhase ProcessImprovementSample Size28,939 units5,410 unitsStatisticallysignificantProcess 0.090.64611%Capability(INCAPABLE)(APPROACHING)IMPROVEMENT(Cpk)Standard 0.83%0.46%44% reductionDeviationPVP-I Particle 82 μm (+116%)58 μm (+53%)ControlledSizeagglomerationThree-Phase Process Specifications:Phase 1—Powder Phase: Dry powder addition with inert gas protection (nitrogen, argon, helium) preventing hygroscopic powder moisture absorption. Pre-measured dosing ensures consistent delivery.Phase 2—Liquid Phase: Liquid addition with process enhancements: about 35° C. heating for aluminum chlorohydrate systems, nitrogen purge for anhydrous conditions.

[0045] Phase 3—Propellant Phase: Propellant addition with precision nozzles preventing powder deposit on canister chime, ensuring proper valve sealing.

[0046] Scanning electron microscopy shows conventional slurry processing increases PVP-I particle size from 38 to 82 microns (116% increase), causing actuator clogging in ICH Q7 stability studies, as shown in FIGS. 6A-6B. Major corporations acknowledge these problems: Unilever publicly stated “We've heard from our fans that your go-to Living Proof Dry Shampoo wasn't spraying properly. Trust us, we feel your pain.” (as stated by Unilever on Jan. 30, 2025.

[0047] FIG. 6A is a SEM image of PVP-I raw powder (about 38 μm baseline).

[0048] FIG. 6B is a SEM image of PVP-I after slurry processing (about 82 μm, about 116% agglomeration increase).

[0049] FIG. 6C is a SEM image of PVP-I after three-phase processing according to the present invention (about 58 μm, controlled increase).Equipment Specifications:

[0050] Specialized powder filling equipment includes: antistatic coating preventing powder adhesion; orbital welding eliminating accumulation crevices; stainless steel mirror polish (Ra<0.4 μm) for smooth flow; intrinsically safe design with mechanical powder contact zone separated from electrical components; chime-protection nozzles preventing valve failures.Evidence SummaryUnexpected Results: about an 611% Cpk improvement (about 0.09→about 0.64); Particle size control (about 38 μm→about 58 μm vs. about 82 μm slurry); Process time reduction (between about 8 to about 72 hours→2 about hours), as shown in FIGS. 6B-6C.

[0052] Industry Recognition: Unilever acknowledgment of unsolved problems; $60+ billion corporation couldn't solve with conventional methods; Public admission of product failures

[0053] Commercial Success: Three successful product lines; ICH Q7 stability compliance; about a 6% material cost savings; Zero consumer complaints.

[0054] The present invention may be further understood in connection with the following Examples and embodiments. The following non-limiting Examples and also embodiments described throughout this application are provided to illustrate the invention.EXAMPLES

[0055] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices and / or methods claimed herein are made and evaluated, and are intended to be purely exemplary of the invention and are not intended to limit the scope of what the inventors regard as their invention. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the invention.

[0056] Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in ° C. or is at ambient temperature, and pressure is at or near atmospheric.Example 1: Dry Shampoo Powder Spray

[0057] A dry shampoo powder spray is prepared according to the following 3 Phases:Phase 1Phase 2Phase 3Mixture of Rice Starch,Mixture of Ethanol,Propellant or mixture ofCetrimonium Chloride,fragrance, extracts, siliconespropellants-HFC152A,Kaolin, DistearyldimoniumIsobutane, PropaneChloride~7-~10% w / w~3-~6% w / w~80-~90% w / wExample 2: Anti-Chafing Spray

[0058] An anti-chafing spray is prepared according to the following 3 Phases:Phase 1-Powder blendPhase 2-Liquid blendPhase 3-Propellant blendMixture of Corn / Rice / Mixture of alcohol, silicone,Mixture of propellants-HFCTapioca Starch,sorbitan oleate, bisabolol,152a, propane, isobutaneBenzothonium Chloride,isopropylmyristate, fragrance,Calamine Powder, Kaolin,essential oilsSodium Bicarbonate,Magnesium Stearateabout 8-abount 12% w / wabout 8-about 12% w / wabout 75-about 85% w / w

[0059] The powder filling equipment is a commercially available equipment that was customized to include special filling nozzles that place powder directly into the 1-inch canister opening without any powder deposit on the chime of the canister. Additionally, special coatings and augers were customized to create accurate dosing for free-flowing powders and non-free flowing powders so the equipment can handle all powder technologies despite their flow or coagulating characteristics. Additionally, the equipment was customized to make the unit intrinsically safe for operations around flammable powders and / or electrostatically charged powders.Example 3: Dry Shampoo Powder SprayPhase 1: Rice Starch, Cetrimonium Chloride, Kaolin, Distearyldimonium Chloride (between about 7-about 10% w / w);

[0061] Phase 2: Ethanol, fragrance, extracts, silicones (between about 3-about 6% w / w);

[0062] Phase 3: HFC152A, Isobutane, Propane (between about 80-about 90% w / w).

[0063] Results: Elimination of consumer complaints (Unilever acknowledgment proves industry problem), about 6% material savings through reduced overfill (between about 116-about 120 g vs. between about 122-about 127 g), resolution of hygroscopic powder handling challenges.Example 4: Antiperspirant SprayPhase 1: Aluminum Chlorohydrate (MICRO-DRY 323), starches, other powders (between about 10-about 14% w / w);

[0065] Phase 2: Alcohol, silicone, carriers—heated to about 35° C. with nitrogen purge (remainder); and

[0066] Phase 3: HFC 152a, propane, isobutane (between about 55-about 70% w / w).

[0067] Results: Head-to-head comparison with identical formulations: Cpk improvement from about 0.09 to about 0.64 (about 611% increase), mean API about 19.42% to about 20.08% (closer to about 20.20% target), standard deviation reduced about 44%, process time reduced from between about 8-about 72 hours to about 2 hours.Example 5: PVP-I Antiseptic SprayPhase 1: Povidone-Iodine Complex powder (between about 4-about 8% w / w);

[0069] Phase 2: Isopropyl Myristate liquid carrier (between about 3-about 7% w / w); and

[0070] Phase 3: N-Pentane, Propane / Butane propellant blend (between about 85-about 93% w / w).

[0071] SEM Analysis Results: —Raw powder: 38 μm average (baseline) —Slurry processing: about 82 μm average (about 116% agglomeration increase) —Three-phase processing: about 58 μm average (about 53% controlled increase), as shown in FIG. 6C.

[0072] Results: Zero actuator clogging in ICH Q7 stability studies vs. systematic slurry failures, particle size control enabling regulatory compliance, consistent API potency delivery.

[0073] The use of the terms “a,”“an,”“the,” and similar referents in the context of describing the present invention (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context.

[0074] Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. Use of the term “about” is intended to describe values either above or below the stated value in a range of approximately ±10%; in other embodiments, the values may range in value above or below the stated value in a range of approximately ±5%; in other embodiments, the values may range in value above or below the stated value in a range of approximately ±2%; in other embodiments, the values may range in value above or below the stated value in a range of approximately ±1%. The preceding ranges are intended to be made clear by context, and no further limitation is implied. All method steps described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise stated. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0075] As used herein the term “method” refers to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the chemical, mechanical, biochemical and medical arts. Unless otherwise expressly stated, it is in no way intended that any method or aspect set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not specifically state in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including matters of logic with respect to arrangement of steps or operational flow, plain meaning derived from grammatical organization or punctuation, or the number or type of aspects described in the specification.

[0076] While in the foregoing specification the present invention has been described in relation to certain embodiments thereof, and many details have been put forth for the purposes of illustration, it will be apparent to those skilled in the art that the invention is susceptible to additional embodiments and that certain of the details described herein can be varied considerably without departing from the basic principles of the invention.

[0077] The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.

Examples

example 1

Dry Shampoo Powder Spray

[0057]A dry shampoo powder spray is prepared according to the following 3 Phases:

Phase 1Phase 2Phase 3Mixture of Rice Starch,Mixture of Ethanol,Propellant or mixture ofCetrimonium Chloride,fragrance, extracts, siliconespropellants-HFC152A,Kaolin, DistearyldimoniumIsobutane, PropaneChloride~7-~10% w / w~3-~6% w / w~80-~90% w / w

example 2

Anti-Chafing Spray

[0058]An anti-chafing spray is prepared according to the following 3 Phases:

Phase 1-Powder blendPhase 2-Liquid blendPhase 3-Propellant blendMixture of Corn / Rice / Mixture of alcohol, silicone,Mixture of propellants-HFCTapioca Starch,sorbitan oleate, bisabolol,152a, propane, isobutaneBenzothonium Chloride,isopropylmyristate, fragrance,Calamine Powder, Kaolin,essential oilsSodium Bicarbonate,Magnesium Stearateabout 8-abount 12% w / wabout 8-about 12% w / wabout 75-about 85% w / w

[0059]The powder filling equipment is a commercially available equipment that was customized to include special filling nozzles that place powder directly into the 1-inch canister opening without any powder deposit on the chime of the canister. Additionally, special coatings and augers were customized to create accurate dosing for free-flowing powders and non-free flowing powders so the equipment can handle all powder technologies despite their flow or coagulating characteristics. Additionally, the e...

example 3

Dry Shampoo Powder Spray

Phase 1: Rice Starch, Cetrimonium Chloride, Kaolin, Distearyldimonium Chloride (between about 7-about 10% w / w);[0061]Phase 2: Ethanol, fragrance, extracts, silicones (between about 3-about 6% w / w);[0062]Phase 3: HFC152A, Isobutane, Propane (between about 80-about 90% w / w).[0063]Results: Elimination of consumer complaints (Unilever acknowledgment proves industry problem), about 6% material savings through reduced overfill (between about 116-about 120 g vs. between about 122-about 127 g), resolution of hygroscopic powder handling challenges.

Claims

1. A process of filling an aerosol canister without having to form a liquid-powder slurry prior to filling, comprising a first phase, a second phase, and a third phase; the first phase comprising adding powder to an aerosol canister; the second phase comprising adding liquid to the aerosol canister, wherein the powder remains in powder format without any contact with liquid until the point of filling to prevent particle agglomeration that increases particle size beyond functional spray requirements; and the third phase comprises adding propellant to the aerosol canister to complete the filling of the canister, wherein the powder maintains its potency and particle size integrity to form a final aerosol product.

2. The process of claim 1, wherein the first phase comprises a powder blend including a mixture of Corn / Rice / Tapioca Starch, Benzothonium Chloride, Calamine Powder, Kaolin, Sodium Bicarbonate, Magnesium Stearate between about 10% w / w and about 14% w / w, wherein the powder remains in powder format without contact with liquid until the point of filling to prevent particle agglomeration that would increase average particle size by more than 75% as demonstrated through comparative particle size analysis; the second phase comprises a liquid blend including a mixture of alcohol, silicone, sorbitan oleate, bisabolol, isopropylmyristate, fragrance, essential oils comprising the remainder after powder and propellant phases, wherein the liquid phase is heated to approximately 35° C. and nitrogen purge is applied to maintain anhydrous conditions; and the third phase comprises a propellant blend including HFC 152a, propane, and isobutane between about 55% w / w and about 70% w / w, wherein the process achieves statistical process control capability (Cpk) improvement from below 0.20 to above 0.60 compared to conventional slurry-based methods.

3. The process of claim 2, further comprising specialized powder filling equipment including filling nozzles that place powder directly into a 1-inch canister opening without any powder deposit on a chime of the canister to prevent propellant leakage during valve crimping, wherein the powder filling equipment includes: (a) an inert gas blanket system using nitrogen, argon, or helium at controlled flow rates to protect hygroscopic powders from moisture absorption during filling, (b) antistatic coating on all auger surfaces contacting powder to prevent electrostatic powder adhesion, (c) orbital welding construction eliminating crevices where powder accumulation could occur, (d) stainless steel mirror polish surfaces having Ra values below 0.4 micrometers for smooth powder flow, and (e) intrinsically safe design with mechanical powder contact zones separated from electrical components for safe handling of flammable and electrostatically charged powders, wherein the equipment enables pre-measured powder delivery in a single continuous dose to prevent dosing variations and maintain particle size control as demonstrated by comparative scanning electron microscopy analysis showing particle size increase limited to below 60% compared to baseline measurements.

4. The process of claim 3, wherein the first phase comprises Povidone-Iodine Complex powder between about 4% w / w and about 8% w / w; the second phase comprises Isopropyl Myristate liquid carrier between about 3% w / w and about 7% w / w; and the third phase comprises a propellant blend including N-Pentane and Propane / Butane between about 85% w / w and about 93% w / w, wherein the process prevents particle agglomeration as demonstrated by scanning electron microscopy showing controlled particle size maintenance compared to conventional slurry processing that causes severe agglomeration and actuator clogging failures.

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