Patent Publication Number: US-2023149958-A1

Title: Device for supplying a composition to a pressurized deposition system

Description:
PRIORITY CLAIM 
     This application claims priority to U.S. Provisional Application Serial No. 62/798,745 filed Jan. 30, 2019, the entire contents of which is hereby incorporated by reference herein. 
    
    
     FIELD OF INVENTION 
     The present invention relates to devices and methods for applying a composition onto a keratinous surface, e.g., a person’s skin. More specifically, the invention relates to devices and methods for applying a pressurized topical composition (e.g., a cosmetic composition or a skin treatment composition) to enhance the aesthetic appearance of skin. 
     BACKGROUND 
     Topical compositions having a variety of different forms, e.g., powder, liquid, viscous fluid, pressed compact, etc., may be applied to a keratinous surface, such as the skin of a user, to impart a desired benefit. In particular, the composition may be applied to the skin of the user to impart an improved aesthetic appearance to the skin. The composition may be applied to desired regions of the skin in a variety of different ways. For example, powdered compositions may be applied to the skin by manually transferring the composition via a brush. A viscous fluid composition, such as a liquid foundation composition, may be applied to the skin by manually distributing and smearing across a large area of the keratinous surface the composition with the user’s fingers or a sponge. 
     SUMMARY OF THE INVENTION 
     One exemplary embodiment of the present invention is directed to a handheld device. The device comprising a reservoir configured to store a fluid topical composition and to dispense a pressurized flow of the composition. The device also comprises an accumulator including an expandable chamber in fluidly communication with the reservoir. The expandable chamber is biased towards a deflated configuration so that, when filled with the composition the chamber expands against this bias applying pressure to the composition stored therein. The device further comprises a supply valve between the reservoir and the accumulator regulating the flow of the composition from the reservoir to the accumulator, and a pressure sensor generating pressure data corresponding to a pressure of the composition in the accumulator. The device also includes a processing arrangement receiving the pressure data from the pressure sensor, analyzing the pressure data to determine whether the pressure in the accumulator is above a predetermined threshold value and controlling the supply valve to maintain the pressure of the accumulator within a range between the predetermined threshold value and a predetermined ceiling value. In addition, the device comprises a deposition arrangement fluidly connected to an outlet of the accumulator and dispensing the composition from the accumulator under control of the processing arrangement. 
     A method for dispensing a topical composition is also described. The method comprises supplying, via a supply valve, a pressurized flow of the composition to an accumulator including an expandable chamber therein. The expandable chamber is biased towards a deflated configuration so that, when filled with the composition the chamber expands against this bias applying pressure to the composition stored therein. The method also comprises generating, by a pressure sensor, pressure data corresponding to a pressure of the composition in the accumulator. The method further comprises analyzing, by a processing arrangement the pressure data received from the pressure sensor to determine whether the pressure in the accumulator is above a predetermined threshold value and to control the supply valve to maintain the pressure of the accumulator within a range between the predetermined threshold value and a predetermined ceiling value. The method further comprises dispensing, by a deposition arrangement fluidly connected to an outlet of the accumulator, the composition from the accumulator under control of the processing arrangement. 
     A method for purging fluid from air-exposed regions of a topical sprayer is also provided. The method comprises supplying, via a supply valve, a pressurized flow of a topical composition to an accumulator including an expandable chamber therein. The expandable chamber is biased towards a deflated configuration so that, when filled with the composition the chamber expands against this bias applying pressure to the composition stored therein. The method also comprises generating, by a pressure sensor, pressure data corresponding to a pressure of the composition in the accumulator. The method further comprises analyzing, by a processing arrangement, the pressure data received from the pressure sensor to determine whether the pressure in the accumulator is above a cleaning threshold value and to control the supply valve to maintain the pressure of the accumulator above the cleaning threshold value. The method further comprises dispensing, by a deposition arrangement fluidly connected to an outlet of the accumulator, the composition from the accumulator under control of the processing arrangement until the pressure in the accumulator falls below a predetermined ceiling value. The cleaning threshold value is higher than the predetermined ceiling value. The cleaning threshold value is also selected such that the deposition arrangement dispenses the composition from the accumulator at a pressure that provides force sufficient to dislodge obstructions in the deposition arrangement. 
     These and other aspects of the invention will become apparent to those skilled in the art after a reading of the following detailed description of the invention, including the figures and appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG.  1    shows a block diagram of an exemplary device for applying a composition to the skin of a user, according to an exemplary embodiment of the present application. 
         FIG.  2    shows an exemplary embodiment of a reservoir charged with the composition that can be used with the exemplary device shown in  FIG.  1   . 
         FIG.  3    shows an alternative exemplary embodiment of a reservoir charged with the composition that can be used with the exemplary device shown in  FIG.  1   . 
         FIG.  4    shows an exemplary method for applying a composition to the skin of a user, according to an exemplary embodiment of the present application. 
         FIG.  5    shows an exemplary method for operating an exemplary device in a cleaning mode, according to an exemplary embodiment of the present application. 
     
    
    
     DETAILED DESCRIPTION 
     The present application provides a device and method for applying a pressurized composition to a keratinous substrate, e.g., a surface of the skin. In particular, the device of the present application controls delivery of a pressurized fluid composition to the keratinous substrate and is capable of being used while the device is held in any orientation, including an inverted orientation. Embodiments of the device receive a supply of the composition having a high initial pressure and dispense the composition at a reduced pressure suitable for application to a biologic surface, such as, for example, the skin of the face (e.g., suitably pressured to be tolerable to the person without significant pain during use or damage to the skin). The reduced pressure may also be selected to be suitable for dispensing the composition to form a thin layer of the composition on the skin. Preferably, the reduced pressure is selected to more controllably dispense the composition in a thin layer onto a desired area of skin as compared to higher pressures. The pressure may be selected to dispense the composition in a plurality of pulses such that the layer of composition formed on the substrate from each pulse covers a suitably sized area that repeated dispensing of pulses of the composition across the substrate allows for detailed and controlled application of the composition. For example, repeated dispensing of pulses of the composition across the skin allows for detailed and controlled application of a cosmetic composition to impart an aesthetically pleasing look. The devices and methods of the present invention may also be directed to applying a pressurized composition onto biologic surfaces other than a person’s skin. Other applications include, but are not limited to, applying a pressurized composition to the teeth or eyes, or to mucous membranes near the eyes and ears, or inside the nose, mouth, lip, vagina, the urethral opening or the anus of the person. 
       FIG.  1    shows a diagram of an exemplary device  100  for applying a fluid composition, e.g., a fluid skin treatment composition or a fluid cosmetic composition, to a keratinous substrate such as skin. The device  100  of this embodiment is sized and shaped to be a handheld device designed to be held within a palm of a user’s hand. 
     The fluid composition may comprise, for example, any suitable cosmetic ingredients for modifying an appearance of the skin, such as, for example, an opaque substance, a tinted cosmetic, or any other suitable compositions for enhancing the appearance of skin. The composition may also comprise ingredients such as a moisturizer for hydration, a carrier, or a benefit agent (e.g., a beneficial compound/composition /extract or an active ingredient) for treating and/or ameliorating a skin condition, e.g, acne, hyperpigmentation, eczema, hives, vitiligo, psoriasis, rosacea, warts, shingles, cold sore, pigmentation and tone, redness/oxidative skin stress, wrinkles, brightening, sagging/elasticity, etc. Exemplary embodiments of benefit agents that may be incorporated into the composition arc further described below. 
     A non-limiting list of useful hydrating active benefit agents includes hyaluronic acid, and humectants. The hyaluronic acid may be linear, cross-linked, or a mixture of linear and cross-linked hyaluronic acid. It may be in a salt form, such as sodium hyaluronate. A humectant is a compound intended to increase the water content of the top layers of skin (e.g., hygroscopic compounds). Examples of suitable humectants include, but are not limited to, glycerin, sorbitol or trehalose or a salt or ester thereof. 
     A non-limiting list of useful benefit agents for acne includes benzoyl peroxide, retinoids including retinol, retinal, retinoic acid, retinyl acetate, and retinyl palmitate, hydroxy acids include, but are not limited, to glycolic acid, lactic acid, malic acid, salicylic acid, citric acid, and tartaric acid, sulfur, Zinc PCA (Zinc Pyrrolidone carboxylic acid), Allantoin (5-ureidohydantoin), Rosemary, 4-hexylresoreinol, N-acetyl glucosamine, gluconolactone, niacinamide, azelaic acid, and resveratrol. 
     A non-limiting list of useful pigmentation active benefit agents includes resorcinols, such as niacinamide, 4-hexyl resorcinol, curcuminoids (such as Sabiwhite (Tetrahydrocurcumin), phytic acid, resveratrol, soybean glycine soja oil, gluconolactone, azelaic acid, and retinoids including retinol, retinal, retinoic acid, retinyl acetate, and retinyl palmitate, enzymes such as laccase, tyrosinase inhibitors, melanin-degradation agents, melanosome transfer inhibiting agents including PAR-2 antagonists, exfoliants, sunscreens, retinoids, antioxidants, Tranexamic acid, tranexamic acid cetyl ester hydrochloride, skin bleaching agents, linoleic acid, adenosine monophosphate disodium salt, Chamomilla extract, allantoin, opacifiers, tales and silicas, zinc salts, and the like. Examples of suitable tyrosinase inhibitors include but, are not limited to, Vitamin C and its derivatives, Vitamin E and its derivatives, Kojic Acid, Arbutin, resorcinols, hydroquinone, Flavones e.g., Licorice flavanoids. Licorice root extract, Mulberry root extract, Dioscorea Coposita root extract, Saxifraga extract and the like, Ellagic acid, Salicylates and derivatives, Glucosamine and derivatives, Fullerene, Hinokitiol, Dioic acid, Acetyl glucosamine, 5,5′-dipropyl-biphenyl-2,2′-diol (Magnolignan), 4-(4-hydroxyphenyl)-2-butanol (4-HPB), combinations of two or more thereof, and the like. Examples of vitamin C derivatives include, but are not limited to, ascorbic acid and salts, Ascorbic Acid-2-Glucoside, sodium ascorbyl phosphate, magnesium ascorbyl phosphate, and natural extract enriched in vitamin C. Examples of vitamin E derivatives include, but are not limited to, alpha-tocopherol, beta, tocopherol, gamma-tocopherol, delta-tocopherol, alpha-tocotrienol, beta-tocotrienol, gamma-tocotrienol, delta-tocotrienol and mixtures thereof, tocopherol acetate, tocopherol phosphate and natural extracts enriched in vitamin E derivatives. Examples of resorcinol derivatives include, but are not limited to, resorcinol, 4-substituted resorcinols like 4-alkylresorcinols such as 4-butyresorcinol (rucinol), 4-hexylresorcinol, phenylethyl resorcinol, 1-(2,4-dihydroxyphenyl)-3-(2,4-dimethoxy-3-methylphenyl)-Propane and the like and natural extracts enriched in resorcinols. Examples of salicylates include, but are not limited to, 4-methoxy potassium salicylate, salicylic acid, acetylsalicylic acid, 4-methoxysalicylic acid and their salts. In certain preferred embodiments, the tyrosinase inhibitors include a 4-substituted resorcinol, a vitamin C derivative, or a vitamin E derivative 
     A non-limiting list of useful redness/antioxidant active benefit agents includes watersoluble antioxidants such as sulfhydryl compounds and their derivatives (e.g., sodium metabisulfite and N-acetyl-cysteine), lipoic acid and dihydrolipoic acid, resveratrol, lactoferrin, and ascorbic acid and ascorbic acid derivatives (e.g., ascorbyl palmitate and ascorbyl polypeptide). Oil-soluble antioxidants suitable for use in the compositions of this invention include, but are not limited to, butylated hydroxytoluene, retinoids (e.g., retinol and retinyl palmitate), tocopherols (e.g., tocopherol acetate), tocotrienols, and ubiquinone. Natural extracts containing antioxidants suitable for use in the compositions of this invention, include, but not limited to, extracts containing flavonoids and isoflavonoids and their derivatives (e.g., genistein and diadzein), extracts containing resveratrol and the like. Examples of such natural extracts include grape seed, green tea, pine bark, propolis and extracts of feverfew. By “extracts of feverfew,” it is meant extracts of the plant “Tanacetum parthenium,” One particularly suitable feverfew extract is commercially available as about 20% active feverfew. 
     A non-limiting list of useful wrinkle active benefit agents includes N-acetyl glucosamine, 2-dimethylaminoethanol, copper salts such as copper chloride, peptides like argireline, syn-ake and those containing copper, coenzyme Q10, dill, blackberry, princess tree, picia anomala, and chicory, resorcinols, such as 4-hexyl resorcinol, curcuminoids and retinoids including retinol, retinal, retinoic acid, retinyl acetate, and retinyl palmitate, hydroxy acids include, but are not limited, to glycolic acid, lactic acid, malic acid, salicylic acid, citric acid, and tartaric acid. 
     A non-limiting list of useful brightening active benefit agents includes Vitamin C and its derivatives such as Ascorbic Acid 2-Glucoside, alpha-hydroxy acids such as lactic acid, glycolic acid, malic acid, tartaric acid, citric acid, or any combination of any of the foregoing, beta-hydroxy acids such as salicylic acid, polyhydroxy acids such as lactobionic acid and gluconic acid, 
     A non-limiting list of useful benefit agents for sagging skin includes blackberry extracts, cotinus extracts, feverfew extracts, extracts of Phyllanthus niruri and bimetal complexes having copper and/or zinc constituents. The bimetal complex having copper and/or zinc constituents may be, for example, copper-zinc citrate, copper-zinc oxalate, copper-zinc tartarate, copper-zinc malate, copper-zinc succinate, copper-zinc malonate, copper-zinc maleate, copper-zinc aspartate, copper-zinc glutamate, copper-zinc glutarate, copper-zinc fumarate, copper-zinc glucarate, copper-zinc polyacrylic acid, copper-zinc adipate, copper-zinc pimelate, copper-zinc subcrate, copper-zinc azealate, copper-zinc sebacate, copper-zinc dodccanoate, or combinations thereof. 
     Additional skin benefit agents or actives may include those actives listed in the following paragraphs. While some of these actives may have been listed above, they arc included below to ensure a more robust listing. 
     Examples of suitable additional benefit agents include: skin lightening agents, darkening agents, anti-aging agents, tropoelastin promoters, collagen promoters, anti-acne agents, shine control agents, anti-microbial agents such as anti-yeast agents, anti-fungal, and anti-bacterial agents, anti-inflammatory agents, anti-parasite agents, external analgesics, sunscreens, photoprotectors, antioxidants, keratolytic agents, detergents/surfactants, moisturizers, nutrients, vitamins, energy enhancers, anti-perspiration agents, astringents, deodorants, hair removers, hair growth enhancing agents, hair growth delaying agents, firming agents, hydration boosters, efficacy boosters, anti-callous agents, agents for skin conditioning, anti-cellulitc agents, fluorides, teeth whitening agents, anti-plaque agents, and plaque-dissolving agents, odor-control agents such as odor masking or pH-changing agents, and the like. Examples of various suitable additional cosmetically acceptable actives include UV filters such as but not limited to avobenzone (Parsol 1789), bisdisulizole disodium (Neo Heliopan AP), diethylamino hydroxybenzoyl hexyl benzoate (Uvinul A Plus), ecamsule (Mexoryl SX), methyl anthranilate, 4-aminobenzoic acid (PABA), cinoxate, ethylhexyl triazone (Uvinul T 150), homosalate, 4-methylbenzylidene camphor (Parsol 5000), octyl methoxycinnamate (Octinoxate), octyl salicylate (Octisalate), padimate O (Escalol 507), phenylbenzimidazole sulfonic acid (Ensulizole), polysilicone-15 (Parsol SLX), trolamine salicylate, Bemotrizinol (Tinosorb S), benzophenones 1-12, dioxybenzone, drometrizole trisiloxane (Mexoryl XL), iscotrizinol (Uvasorb HEB), octocrylene, oxybenzone (Eusolex 4360), sulisobenzone, bisoctrizole (Tinosorb M), titanium dioxide, zinc oxide, carotenoids, free radical scavengers, spin traps, retinoids and retinoid precursors such as retinol, retinoic acid and retinyl palmitate, ceramides, polyunsaturated fatty acids, essential fatty acids, enzymes, enzyme inhibitors, minerals, hormones such as estrogens, steroids such as hydrocortisone, 2-dimethylaminoethanol, copper salts such as copper chloride, peptides containing copper such as Cu:Gly-His-Lys, coenzyme Q1 0, amino acids such a proline, vitamins, lactobionic acid, acetyl-coenzyme A, niacin, riboflavin, thiamin, ribose, electron transporters such as NADH and FADH2, and other botanical extracts such as oat, aloe vera, Feverfew, Soy, Shiitake mushroom extracts, and derivatives and mixtures thereof. 
     Examples of suitable skin lightening benefit agents include, but are not limited to, tyrosinase inhibitors, melanin-degradation agents, melanosome transfer inhibiting agents including PAR-2 antagonists, exfoliants, sunscreens, retinoids, antioxidants, Tranexamic acid, tranexamic acid cetyl ester hydrochloride, skin bleaching agents, linoleic acid, adenosine monophosphate disodium salt, Chaniomilla extract, allantoin, opacifiers, talcs and silicas, zinc salts, and the like. 
     Examples of suitable tyrosinase inhibitors include but, are not limited to, Vitamin C and its derivatives, Vitamin E and its derivatives, Kojic Acid, Arbutin, resorcinols, hydroquinone, Flavones e.g. Licorice flavanoids, Licorice root extract, Mulberry root extract, Dioscorea Coposita root extract, Saxifraga extract and the like, Ellagic acid, Salicylates and derivatives, Glucosamine and derivatives, Fullerene, Hinokitiol, Dioic acid, Acetyl glucosamine, 5,5*-dipropyl-biphenyl-2,2′-diol (Magnolignan), 4-(4-hydroxyphenyl)-2-butanol (4-HPB), combinations of two or more thereof, and the like. Examples of vitamin C derivatives include, but are not limited to, ascorbic acid and salts, Ascorbic Acid-2-Glucoside, sodium ascorbyl phosphate, magnesium ascorbyl phosphate, and natural extract enriched in vitamin C. Examples of vitamin E derivatives include, but are not limited to, alpha-tocopherol, beta, tocopherol, gamma-tocopherol, delta-tocopherol, alpha-tocotrienol, beta-tocotrienol, gamma-tocotrienol, delta-tocotrienol and mixtures thereof, tocopherol acetate, tocopherol phosphate and natural extracts enriched in vitamin E derivatives. Examples of resorcinol derivatives include, but are not limited to, resorcinol, 4-substituted resorcinols like 4-alkylresorcinols such as 4-butyresorcinol (rucinol), 4-hexylresorcinol (Synovea HR, Sytheon), phenylethyl resorcinol (Symwhite, Symrise). 1-(2,4-dihydroxypheny))-3-(2.4-dimethoxy-3-methylphenyl)-Propane nivitol, Unigen) and the like and natural extracts enriched in resorcinols. Examples of salicylates include, but are not limited to, 4-methoxy potassium salicylate, salicylic acid, acetylsalicylic acid, 4-methoxysalicylic acid and their salts. In certain preferred embodiments, the tyrosinase inhibitors include a 4-substituted resorcinol, a vitamin C derivative, or a vitamin E derivative. In more preferred embodiments, the tyrosinase inhibitor comprises Phenylethyl resorcinol, 4-hexyl resorcinol, or ascorbyl-2-glucoside. 
     Examples of suitable melanin-degradation agents include, but are not limited to, peroxides and enzymes such as peroxidases and ligninases. In certain preferred embodiments, the melanin-inhibiting agents include a peroxide or a ligninase. 
     Examples of suitable melanosome transfer inhibiting agents including PAR-2 antagonists such as soy trypsin inhibitor or Bowman-Birk Inhibitor, Vitamin B3 and derivatives such as Niacinamide, Essential soy, Whole Soy, Soy extract. In certain preferred embodiments, the melanosome transfer inhibiting agents includes a soy extract or niacinamide. 
     Examples of exfoliants include, but are not limited to, alpha-hydroxy acids such as lactic acid, glycolic acid, malic acid, tartaric acid, citric acid, or any combination of any of the foregoing, beta-hydroxy acids such as salicylic acid, polyhydroxy acids such as lactobionic acid and gluconic acid, and mechanical exfoliation such as microdermabrasion. In certain preferred embodiments, the exfoliant include glycolic acid or salicylic acid. 
     Examples of sunscreens include, but are not limited to, avobenzone (Parsol 1789), bisdisulizole disodium (Neo Heliopan AP), diethylamino hydroxybenzoyl hexyl benzoate (Uvinul A Plus), ecamsule (Mexoryl SX), methyl anthranilate, 4-aminobenzoic acid (PABA), cinoxatc, ethylhexyl triazone (Uvinul T 150), homosalate, 4-methylbenzylidene camphor (Parsol 5000), octyl methoxycinnamate (Octinoxate), octyl salicylate (Octisalate), padimate O (Escalol 507), phenylbenzimidazole sulfonic acid (Ensulizole), polysilicone-15 (Parsol SLX), trolamine salicylate, Bemotrizinol (Tinosorb S), benzophenones 1-12, dioxybenzonc, drometrizole trisiloxane (Mexoryl XL), iscotrizinol (Uvasorb HEB), octocrylene, oxybenzone (Eusolex 4360), sulisobenzone, bisoctrizole (Tinosorb M), titanium dioxide, zinc oxide, and the like. 
     Examples of retinoids include, but are not limited to, retinol (Vitamin A alcohol), retinal (Vitamin A aldehyde), retinyl acetate, retinyl propionate, retinyl linolcate, retinoic acid, retinyl palmitate, isotretinoin, tazarotene, bexarotene, Adapalene, combinations of two or more thereof and the like In certain preferred embodiments, the retinoid is selected from the group consisting of retinol, retinal, retinyl acetate, retinyl propionate, retinyl linoleate, and combinations of two or more thereof. In certain more preferred embodiments, the retinoid is retinol. 
     Examples of antioxidants include, but are not limited to, water-soluble antioxidants such as sulthydryl compounds and their derivatives (e.g., sodium metabisulfite and N-acetylcysteine, glutathione), lipoic acid and dihydrolipoic acid, stilbenoids such as resveratrol and derivatives, lactoferrin, iron and copper chelators and ascorbic acid and ascorbic acid derivatives (e.g., ascobyl-2-glucoside, ascorbyl palmitate and ascorbyl polypeptide). Oil-soluble antioxidants suitable for use in the compositions of this invention include, but are not limited to, butylated hydroxytoluene, retinoids (e.g., retinol and retinyl palmitate), tocopherols (e.g., tocopherol acetate), tocotrienols, and ubiquinones. Natural extracts containing antioxidants suitable for use in the compositions of this invention, include, but not limited to, extracts containing flavonoids and isoflavonoids and their derivatives (e.g., genistein and diadzein), extracts containing resveratrol and the like. Examples of such natural extracts include grape seed, green tea, black tea, white tea, pine bark, feverfew, parthenolide-free feverfew, oat extracts, blackberry extract, cotinus extract, soy extract, pomelo extract, wheat germ extract, Hesperedin, Grape extract, Portulaca extract, Licochalcone, chalcone, 2,2′-dihydroxy chalcone, Primula extract, propolis, and the like. 
     In some preferred embodiments, useful benefit agents for acne include, but are not limited, salicylic acid. Zinc PCA (Zinc Pyrrolidone carboxylic acid), Allantoin (5-ureidohydantoin), Rosemary. 4-hexylresorcinol, N-acetyl glucosamine, gluconolactone, niacinamide, azelaic acid, and resveratrol. 
     In some preferred embodiments, a list of useful pigmentation active benefit agents includes tetrahydrocurcumin, phytic acid, resveratrol, soybean glycine soja oil, gluconolactone, laccase, 4-hcxyl resorcinol, N-acetyl glucosamine, gluconolactone, niacinamide, azelaic acid, and resveratrol. 
     In some preferred embodiments, a list of useful active benefit agents includes to simultaneously treat acne and pigmentation includes 4-hexyl resorcinol, N-acetyl glucosamine, gluconolactone, niacinamide, azelaic acid, and resveratrol. 
     In an exemplary embodiment, the fluid composition may be a suspension containing particulate materials therein, preferably, the particulates are uniformly distributed and/or suspended in a suitable topical carrier. For example, the fluid composition may comprise a topical carrier and particulates such as, for example, reflectance modifying agents (RMAs) (any component useful for altering reflectance of the skin) .... e.g., pigments and/or high refractive index particles for modifying a reflectance of skin. In particular, the high refractive index particles may comprise particles having a refractive index of 2.0 or greater. In one specific example, the RMA may comprise particles of titanium dioxide. The RMA may comprise or consist of particles of having an average diameter from about 0.35 microns to about 1.35 microns, from about 0.5 microns to about 1.0 microns, or from about 0.6 microns to about 0.8 microns. In one example, the RMA may comprise or consist of particles of having an average diameter of about 0.76 microns. In another example, the RMA may comprise or consist of particles having a distribution of particle sizes with a median diameter at about 0.58 microns. In one example, the RMA may comprise or consist of particles of having a distribution of particle sizes as follows: less than 10% of the particles having a diameter about or less than 0.37 microns, less than 50%) of the particles having a diameter about or less than 0.58 microns, and less than 90% of the particles having a diameter about or less than 1.31 microns. Specifically, the particles may be uniformly distributed and/or suspended in the topical composition (e.g., a liquid suspension). It is contemplated that the fluid composition may have any suitable viscosity for a topical formulation suitable for use on the skin. The fluid composition may, for example, be a thin liquid or a thick viscous fluid. The viscosity of the fluid composition may be selected to be sufficiently viscous to allow particulate materials contained in the fluid composition to remain suspended over a shelf life of the composition and thereby improve stability of the composition during storage, while being sufficiently thin such that the composition can be easily atomized into fine droplets for deposition onto the skin. For example, the fluid composition may have a viscosity at room temperature from about 1 cP to about 1200 cP, about 5 cP to about 1000 cP, or about 8 cP to about 882 cP In some examples, the fluid composition may have a viscosity at room temperature below about 300 cP. 
     The device  100  according to this embodiment comprises a reservoir  102  holding a supply of the fluid composition to be dispensed by the device  100 . The reservoir  102  in this embodiment includes a storage chamber charged with a pressurized supply of the composition therein although, as would be understood by those skilled in the art, multiple storage containers may also be provided, for example, if the composition to be applied is more effective when multiple components are mixed immediately before application. For example, the reservoir  102  may initially be charged with a supply of the composition, and as the device  100  applies the composition to the skin, the amount and/or pressure of the supply contained in the reservoir  102  gradually diminishes. In some embodiments, the reservoir  102  is a removeable container that can be replaced upon exhaustion of one or more of the contents therein. 
     In one exemplary embodiment, as shown in  FIG.  2   , the reservoir  102  comprises a rigid container defining a storage chamber  150  therein for holding the composition  152  and a propellant  154 , and a dispenser  159 , e.g., a valve or nozzle, for dispensing a pressurized flow of the composition  152  when the device is activated. The storage chamber  150  in this embodiment is rigid and does not vary in size or change shape as the pressure within the chamber  150  changes over time (i.e., as the composition is dispensed). For example, the storage chamber  150  may have a volume of about 30 mL or less, about 20 mL or less, or about 15 mL or less. The storage chamber  150  may be charged with any suitable amount of the composition  152 , such as, for example, about 10 mL or less, about 8 mL or less, or about 5 mL or less of the composition  152 , and propellant  154 . More particularly, the reservoir  102  may be any suitable canister having an interior surface that does not cause undesirable interactions between the composition  152  and the canister. For example, the reservoir  102  may be a metal aerosol canister, and preferably, an aluminum aerosol canister, coated with a continuous film of a protective coating that does not react with the composition  152 . The film creates a barrier preventing undesirable interactions between the composition  152  and the canister (e.g., formation of grey color aluminum oxide particulates from the aluminum canister that can discolor the composition  152 ). The protective coating may be a polymer coating, for example, an epoxy-phenolic coating as would be understood by those skilled in the art. 
     The propellant  154  in the storage chamber  150  pressurizes the composition  152  to generate propulsion for dispensing a pressurized flow of the composition  152  from the storage chamber  150  when the dispenser  159  is activated. The storage chamber  150  may be charged with any suitable amount of propellant  154  to pressurize the composition  152  to a desired pressure, such as, for example, within a range from about 5 psi to about 50 psi, from about 10 psi to about 40 psi, or from about 12 psi to about 30 psi. The propellant  154  may be any suitable gaseous propellant  154  that does not react with the composition  152  and that is suitable for topical application, preferably, pressurized air or nitrogen. In this exemplary embodiment, the reservoir  102  further comprises a dip tube  156  having a first end submersed within the composition  152  and a second end operably connected to the dispenser  159  for drawing the composition  152  from the first end to the second end and dispensing the pressurized flow via the dispenser  159  when it is activated. 
     In another exemplary embodiment, the reservoir  102  comprises a bag-on-valve system, an exemplary embodiment of which is shown in  FIG.  3   . The bag-on-valve system includes a flexible bag  172  holding a charge of the composition  152  within an interior chamber defined therein. The bag  172  changes size and shape as the pressure applied outwardly by its contents (and/or pressures applied to the external surface(s) of the bag  172 ) varies during use (e.g., as the contents of the bag  172  are dispensed). The bag  172  is preferably formed from a non-elastic material suitable for storing the composition  152 . In an exemplary embodiment, the bag  172  is formed from two sheets of polymer-laminated aluminum sealed together along outer edges of the internal chamber. An opening of the bag  172  is operably connected (e.g., via a dip tube  177 ) to a dispenser  176  for dispensing a pressurized flow of the composition  152  from the interior chamber when the dispenser  176  is activated. The bag-on-valve system further comprises an external rigid canister  174  that does not vary in size or change shape in response to changing internal pressures during operation of the device  100 . The external canister  174  is suitably sized and shaped to receive the bag  172  therein. In this embodiment, the bag  172  is inserted into the external canister  174  and the canister  174  is further charged with the propellant  154 . The propellant  154  within the external canister  174  exerts pressure against exterior surfaces of the bag  172  to deform the size and shape of the bag  172  and/or pressurize the interior chamber of the bag  172 . Therefore, the composition  152  stored within the interior chamber can be pressurized by the propellant  154  in the exterior canister  174  even though the composition  152  and the propellant  154  are maintained in separate chambers within the bag-on-valve system and do not intermix. Specifically, pressure from the propellant  154  pushes radially inward against the bag  172  compressing the composition  152  therein to generate propulsion for dispensing, via the dispenser  176 , a pressurized flow of the composition  152  from the interior chamber of the bag  172  when the dispenser  176  is activated. 
     In an alternative embodiment, the external canister  174  may include a biasing mechanism (e.g., a spring, or an electronically controlled actuator controlled by the processing arrangement  112  to bias the piston towards an emptied configuration) therein for pushing against and exerting pressure onto exterior surfaces of the bag  172  to deform the size and shape of the bag  172 . Similar to the propellant  154  discussed above, pressure exerted by the biasing mechanism pushes inward against the bag  172  compressing the composition  152  therein to generate propulsion for dispensing, via the dispenser  176 , a pressurized flow of the composition  152  from the interior chamber of the bag  172  when the dispenser  176  is activated. 
     The device  100  further comprises an accumulator  108  defining an expandable chamber  109  for receiving the composition  152  from the reservoir  102 . The reservoir  102  in this embodiment is fluidly connected by a series of conduits  103  and/or valves (e.g., including a supply valve  104 , as will be further described below) to the accumulator  108  to deliver a pressurized flow of the composition  152  to the expandable chamber  109  of the accumulator  108 . The expandable chamber  109  is biased towards a relaxed, deflated configuration in which the expandable chamber  109  is at its minimum size, and expands in response to a force applied against an interior surface of the chamber increasing its internal volume as pressurized material enters the expandable chamber  109 . For example, the expandable chamber  109  is relaxed in a deflated configuration when unfilled. However, the expandable chamber  109  expands as it is charged with increasing amounts of the composition and/or with increasing pressure from the reservoir  102  to exert a force against an interior surface of the expandable chamber  109 . As the composition and/or pressure is discharged from the expandable chamber  109 , the force against the interior surface of the expandable chamber  109  dissipates and the chamber  109  contracts to return toward its deflated configuration. A stiffness of the expandable chamber  109  according to this embodiment is selected to permit expansion of the expandable chamber  109  as material from the reservoir  102  is supplied thereto so that the bias of the expandable chamber  109  exerts on the material therein a desired pressure at which the material is to be dispensed. For example, the expandable chamber  109  according to one exemplary embodiment is formed from materials having a stiffness such that volume of the expandable chamber  109  expands at a rate from about 1 KPa/µL to about 10 KPa/µL, or from about 3 KPa/µL to about 5 KPa/µL, as the expandable chamber  109  is filled with the composition  152  from the pressurized flow dispensed by the reservoir  102 . The expandable chamber  109  of the accumulator  108  preferably has a capacity significantly smaller than that of the reservoir  102 . For example, the accumulator  108  may have a maximum fill capacity, within operating pressures of the device  100 , from about 1 µL, to about 50 µL, from about 2 µL to about 30 µL or from about 5 µL to about 25 µL. Those skilled in the an will understand that this accumulator  108  and the expandable chamber  109  permit the device to maintain a pressure at which the composition is dispensed within a desired range even as the pressure in the reservoir  102  changes during use. 
     In some embodiments, only a portion of the accumulator  108  is formed from elastic material while in other embodiments the entire accumulator  108  is formed of elastic material. When the force against the elastic material is relieved, e.g., as the material in the elastic chamber is discharged and, consequently, the pressure within the expandable chamber  109  decreases, the elastic material returns under its natural bias toward its undeformed configuration. Suitable elastic materials may include, for example, natural or synthetic rubbers, saturated or unsaturated rubbers, elastomers, e.g., silicone elastomers, thermoplastic elastomers, etc. 
     In an alternative embodiment, the accumulator  108  comprises a piston forming a portion of an interior surface of the expandable chamber  109 , and a biasing mechanism attached to the piston biasing the piston towards an emptied configuration, in which the piston is fully advanced such that the expandable chamber  109  is at its minimum size. The biasing mechanism may comprise a spring, compressed air exerting pressure against the piston, and/or an electronically controlled actuator controlled by the processing arrangement to bias the piston towards an emptied configuration. The piston is reversibly operable to advance or retract in response to changing amounts of the composition and/or the changing level of pressure within the expandable chamber  109 . For example, the biasing mechanism is compressed in response to a force exerted against the piston by increasing amounts of the composition and/or increasing pressure within the expandable chamber  109  so that the piston is retracted increasing the size of the expandable chamber  109 . As the force against the piston is relieved, e.g., by discharging the composition and/or pressure from the accumulator  108 , the biasing mechanism extends and returns toward the piston emptied configuration. 
     The device  100  according to this embodiment includes a supply valve  104  disposed between the reservoir  102  and the accumulator  108  that reversibly opens and closes to regulate pressurized flow from the reservoir  102  to the accumulator  108 . The supply valve  104  opens to allow the pressurized flow to pass therethrough into the accumulator  108 . and closes to prevent pressurized flow from entering the accumulator  108 . In some embodiments, the supply valve  104  is adjustable in predetermined increments. For example, the supply valve  104  may reversibly open and close in predetermined increments to incrementally increase or decrease a flow rate and/or a pressure of the pressurized flow passing through the supply valve  104  into the accumulator  108 . 
     The device  100  according to this embodiment also comprises a pressure sensor  106  monitoring pressure of the composition  152  in the accumulator  108 . The pressure sensor  106  may be positioned in any location suitable for detecting a fluid pressure of the composition in the accumulator  108 , for example, the pressure sensor  106  may be located within the accumulator  108  or may be external to the accumulator  108  (e.g., monitoring pressure by detecting a level of expansion of the expandable chamber  109 ). More particularly, the pressure sensor  106  may be mounted onto an interior wall of the expandable chamber  109  of the accumulator  108 . The pressure sensor  106  detects changes in pressure and generates pressure data corresponding to a pressure of the composition in the accumulator  108 . In some embodiments, the pressure sensor  106  may continuously monitor (at any desired frequency and/or rate) and generate pressure data corresponding to pressure of the composition in the accumulator  108  over any desired period of time. 
     The device  100  further comprises an orientation detector  158  monitoring an orientation of the device  100  (e.g., relative to vertical) when it is held by a user. The orientation detector  158  may comprise any suitable device(s) for detecting an orientation of the device  100  such as accelerometers, etc. to determine, for example, when the device  100  is held in a flow restricted configuration during which (depending on the design of the reservoir) an opening of the dip tube  156  may not be within the fluid in the reservoir  102 . At such times, as would be understood by those skilled in the art, the device  100  may be unable to supply fluid to the accumulator  108  and thus, if the expandable chamber  109  is emptied before the device  100  is returned to an upright position, dispensing of the composition may be temporarily unavailable. The orientation detector  158  may detect changes to the position and/or orientation of the device relative to gravity and generate orientation data corresponding to the positioning and/or orientation of the device  100 . As would be understood by those skilled in the art, data from the orientation detector  158  may be used to control the dispensing of composition, to provide feedback to the user to suggest repositioning the device  100 , etc. 
     The pressure sensor  106 , the orientation detector  158 , and/or the supply valve  104  are operably connected to a processing arrangement  112  executing instructions stored on a computer-accessible medium  114 . The processing arrangement  112  in this embodiment receives and analyzes pressure data received from the pressure sensor  106  and controls the supply valve  104 . The processing arrangement  112  may also receive and analyze orientation data received from the orientation detector  158  to further control the supply valve  104 . It is contemplated that the processing arrangement  112  and the computer-accessible medium  114  may be positioned anywhere within or external to the device  100 . The processing arrangement  112  may be, e.g., entirely or a part of, or include, but is not limited to, a computer/processor that can include, e.g., one or more microprocessors, and use instructions stored on a computer-accessible medium  114  (e.g., memory storage device). The computer-accessible medium  114  may, for example, be a non-transitory computer-accessible medium containing executable instructions therein. A storage arrangement may be provided separately from the computer-accessible medium  114 , which may provide the instructions to the processing arrangement  112  to configure the processing arrangement  112  to execute certain exemplary procedures, processes and methods. 
     The device  100  further includes a deposition arrangement  110  for dispensing the composition from the accumulator  108  as a pressurized spray. The deposition arrangement  110  is fluidly connected by a series of conduits  103  and/or valves to the accumulator  108  for obtaining the composition from the accumulator  108  and dispensing the pressurized composition. The deposition arrangement  110  in this embodiment may include, for example, a sprayer (e.g., an electronic sprayer or airbrush sprayer), a drop control device, or any other suitable application device for dispensing a pressurized composition via the deposition arrangement  110 . In one example, the deposition arrangement  110  includes one or more suitable nozzles (and/or valves, atomizers, etc.) for dispensing the composition from the accumulator  108  as a pressurized spray of droplets to form a uniform or substantially uniform thin layer of coverage on the skin. In some embodiments, the deposition arrangement  110  is operably connected to the accumulator  108  to dispense a pressurized spray of the composition from the accumulator  108  without any pressure sources between the accumulator  108  and the deposition arrangement  110 . The pressurized spray in this exemplary embodiment is propelled by the pressure of the composition obtained from the accumulator  108  and does not require any additional pressure sources before dispensing via the deposition arrangement  110 . 
     The nozzle may be any suitable device for dispensing droplets of the composition under pressure as would be understood by those skilled in the art. In certain embodiments, the deposition arrangement  110  comprises multiple nozzles. The use of multiple nozzles can increase an overall rate at which the device  100  may apply the composition to the skin. For example, the deposition arrangement  110  may include 2 to 10 nozzles, 3 to 8 nozzles, or 4 to 6 nozzles, each nozzle being aimed differently so that the composition can be applied to multiple regions on the skin at the same time. In one exemplary embodiment, the deposition arrangement  110  includes 5 nozzles. The nozzle(s) may each comprise a valve operably connected to the processing arrangement  112  for dispensing the composition by rapidly opening and closing the valve to release a pulse of a pressurized spray droplets of the composition. In an exemplary embodiment, the deposition arrangement  110  is operably connected to a processing arrangement  112  executing instructions stored on a computer-accessible medium  114 . The processing arrangement  112  may be further configured to direct and control dispensing of the composition from the accumulator  108  and through the deposition arrangement  110 . 
     The device  100  further comprises a power source (not shown) providing power to control and operate the device  100 . It is contemplated that the power source may be located anywhere within the device  100  or may alternatively be external to the device  100 . In one exemplary embodiment, the power source is operably connected to the supply valve  104 , the pressure sensor  106 , the orientation detector  158 , the processing arrangement  112  and/or the deposition arrangement  110 . Those skilled in the art will understand that various known suitable sources of power may be used. For example, the power source may comprise a battery or a connection to an external source of power. In particular, the power source may comprise a rechargeable battery device. 
     The present application also describes a method for dispensing a pressurized fluid composition. An exemplary method  200  is show in  FIG.  4   . When the device  100  is initially activated, the accumulator  108  may initially be unfilled and in a relaxed, unexpanded configuration. Steps  202  to  206  show an initial start-up stage for priming the accumulator  108  with a pressurized supply of the composition from the reservoir  102 . In this embodiment, an initial supply of the composition is provided to fill the accumulator  108  with the composition until a desired pressure within the accumulator  108  is reached. For example, in step  202 , a pressurized flow of the composition is provided to an expandable chamber  109  of an accumulator  108  via a supply valve  104 . As discussed above, the pressurized flow is, in certain embodiments, dispensed from a reservoir  102  charged with a pressurized supply of the composition. The supply valve  104 , which is disposed between the reservoir  102  and the accumulator  108 , reversibly opens and closes to control the supply of the composition flowing therethrough to the accumulator  108 . The processing arrangement  112  is operably connected to and directs the supply valve  104  to open and/or close as determined by the processing arrangement  112  to achieve and maintain the desired state of the accumulator  108 . In this initial step  202 . the processing arrangement  112  directs the supply valve  104  to open, allowing the pressurized flow from the reservoir  102  to fill the expandable chamber  109  of the accumulator  108  to a desired level. 
     As the pressurized flow is supplied to the accumulator  108 , the pressure sensor  106  monitors and generates pressure data corresponding to the fluid pressure of the composition in the accumulator  108  (step  204 ). The pressure sensor  106  provides real-time or near real-time feedback of the pressure within the accumulator  108 , as the expandable chamber  109  of the accumulator  108  fills with the composition. In step  206 , the processing arrangement  112  receives the pressure data from the pressure sensor  106  and analyzes the pressure data to determine whether the accumulator  108  has been filled with the composition to a desired pressure. More specifically, the processing arrangement  112  analyzes the pressure data to determine whether the pressure within the accumulator  108  has reached or exceeded a predetermined threshold value. If the pressure within the accumulator  108  is below the predetermined threshold value, the processing arrangement  112  directs the supply valve  104  to remain open to continue to supply the pressurized flow to the expandable chamber  109  of the accumulator  108  (step  202 ). If the pressure within the accumulator  108  has reached or exceeded the predetermined threshold value, the processing arrangement  112  directs the supply valve  104  to move to a closed configuration to stop the pressurized flow from filling the accumulator  108 . The predetermined threshold value is preferably selected to be a pressure below a pressure at which the composition is held in the reservoir  102 . More particular, the predetermined threshold value is selected to be a pressure suitable for application to a biologic surface (after passing through the one or more nozzles of the deposition arrangement). For example, the predetermined threshold value may be selected from a range from about 3 psi to about 9 psi, from about 4 psi to about 7 psi. or preferably, about 5 psi. This initial start-up stage (steps  202  to  206 ) may be performed continuously or may be incrementally iterated at a predetermined frequency or rate. For example, steps  202  to  206  may be iterated every 5 seconds, every 3 seconds, or every 1 second until the pressure within the accumulator  108  reaches or exceeds the predetermined threshold value. 
     Once the expandable chamber  109  of the accumulator  108  has been filled to the desired level, the device  100  is adequately primed for dispensing the composition via the deposition arrangement  110 . The deposition arrangement  110  dispenses the composition, for example, as pressurized pulses or as a continuous pressurized stream of the composition. In step  208 , the processing arrangement  112  receives instructions (e.g., based on a user interaction with an actuator or other control) and activates the deposition arrangement  110  to deliver the composition to the skin. The deposition arrangement  110  obtains the composition from the accumulator  108  and dispenses the composition via one or more nozzles, valves, and/or atomizers as a pressurized spray. In some embodiments, the deposition arrangement  110  dispenses the composition from the accumulator  108  to the skin without use of any additional pressure sources, as discussed above. In this exemplary embodiment, the deposition arrangement  110  dispenses the composition at a pressure that is substantially the same as the internal pressure of the accumulator  108 . When multiple nozzles, valves and/or atomizers are used, the pressure of the composition dispensed by each may be the same or substantially the same as one another. Those skilled in the art will understand that, depending on the geometry and number of nozzles, etc. the pressure of the composition leaving the nozzles, etc. may be higher or lower than that of the composition leaving the accumulator  108  so that, the pressure of the composition leaving the accumulator  108  is controlled to achieve a desired pressure leaving the nozzles. 
     As discussed above, the deposition arrangement  110  may comprise one or more nozzle(s) each having a valve operably connected to the processing arrangement  112  for dispensing the composition by rapidly opening and closing the valve to release a pulse of a pressurized spray droplets of the composition. The valve(s) of the deposition arrangement  110  may rapidly open and close within 0.5 ms, within 0.3 ms, within 0.2 ms, or within 0.1 ms, to release a pressurized spray of the composition. Preferably, the pressurized spray has a pressure from about 3 psi to 20 psi, from about 4 psi to about 15 psi, or from about 5 psi to about 10 psi. The accumulator  108  may be suitably configured (e.g., having a size, shape, stiffness and/or pressure) such that a desired amount of the composition is dispensed during each pulse without use of any additional pressure sources. For example, each nozzle, or all of the nozzles within the deposition arrangement  110 , collectively, may dispense during each pulse from about 1 nanoliters to about 50 nanoliters, from 2 nanoliters to about 25 nanoliters, from about 3 nanoliters to about 10 nanoliters or about 5 nanoliters of the composition 
     As the deposition arrangement  110  dispenses pressurized pulses of the composition from the accumulator  108  to the keratinous substrate, pressure within the expandable chamber  109  of the accumulator  108  slowly dissipates. The device  100  may adjust the supply of composition from the reservoir  102  to maintain pressure of the expandable chamber  109  of the accumulator  108  within a desired range, as describes further below in steps  210  to  214 . In steps  210  to  214 , the processing arrangement  112  controls the supply valve  104  and the pressure sensor  106  in a feedback loop to maintain pressure within a desired range, regardless of change in elevation or temperature for the surrounding environment in which the device  100  is used. 
     In step  210 , the pressure sensor  106  continues to monitor the pressure of the expandable chamber  109  as the deposition arrangement  110  dispenses the composition from the accumulator  108  to the skin. In step  212 , the processing arrangement  112  receives the pressure data from step  210  and analyzes the pressure data to determine whether the pressure within the accumulator  108  is within a desired pressure range, in particular, between the predetermined threshold value discussed above, and a predetermined ceiling value. The predetermined ceiling value of this embodiment is less than a pressure of the reservoir  102 . Moreover, the predetermined ceiling value is preferably selected within a predetermined margin of error, within which variabilities are not noticeable when applied to the skin of the user, and do not impact the aesthetic appearance of coverage provided by the composition as applied onto the skin. For example, the predetermined ceiling value may be within 1 psi to 5 psi from the predetermined threshold value. In one exemplary embodiment, the predetermined threshold value may be about 5 psi and the predetermined ceiling value may be about 7 psi. If the pressure within the accumulator  108  is within a range between the predetermined threshold value and a predetermined ceiling value, then the accumulator  108  does not require adjustments. However, if the pressure within the accumulator  108  falls below the predetermined threshold value, the processing arrangement  112  directs the supply valve  104  to re-open to re-supply the pressurized flow to the expandable chamber  109  of the accumulator  108  (step  214 ) and maintain the pressure of the accumulator  108  within the range between the predetermined threshold value and a predetermined ceiling value. 
     The present application also includes a method to operate the device  100  in a cleaning mode. An exemplary method  300  for cleaning the device  100  is show in  FIG.  5   . The device  100  may operate in cleaning mode at any suitable time. For example, the device  100  may operate in a cleaning mode when the device  100  is initially activated for use in a session or upon completion of a session. The device  100  may also operate in a cleaning mode in response to manual input by a user. The device  100  may diverge from normal operations, as exemplified in method  200 , enter into a cleaning mode, as exemplified in method  300 , and resume normal operations, i.e., continuing in method  200 , after the device  100  has completed the cleaning mode. In one exemplary embodiment, when the device  100  is initially activated, the device  100  starts in the cleaning mode as shown in  FIG.  5   . In particular, the exemplary method  300  of the cleaning mode replaces steps  202  to  206  of method  200 . After step  310  is completed, the device  100  may continue to step  208  within method  200  as described above. 
     Steps  302  and  304  are substantially similar to steps  202  and  204  described above. However, in step  306 , the processing arrangement  112  receives pressure data from the pressure sensor  106  and analyzes the pressure data to determine whether the accumulator  108  has been sufficiently filled with the composition to reach a cleaning threshold value. The cleaning threshold value is selected to be a pressure higher than the predetermined threshold value and/or the predetermined ceiling value. The cleaning threshold value is preferably selected to be a pressure below the pressure of the reservoir  102  so that additional pressure sources are not necessary for operating the device  100  in the cleaning mode. In some embodiments, the cleaning threshold value is selected so that the deposition arrangement  110  dispenses the composition from the accumulator  108  at a pressure that provides force sufficient to dislodge obstructions, such as, for example, dried and caked-on composition, in the deposition arrangement  110 . For example, the predetermined threshold value may be selected from a range from about 5 psi to about 20 psi, from about 6 psi to about 15 psi, or preferably, about 10 psi. Steps  302  to  306  may be performed continuously or incrementally iterated at a predetermined frequency or rate. For example, steps  302  to  306  may be iterated every 5 seconds, every 3 seconds, or every 1 second until the pressure within the accumulator  108  is sufficiently raised to exceed the cleaning threshold value. 
     In step  308 , the deposition arrangement  110  discharges the composition from the accumulator  108  via one or more nozzles, valves and/or atomizers to dispense a pressurized pulse or pressurized flow of the composition. The deposition arrangement  110  may initially dispense the composition from the accumulator  108  at a pressure that meets or exceeds the cleaning threshold value, but slowly dissipate as the deposition arrangement  110  dispenses pressurized pulses of the composition from the accumulator  108 . Preferably, the deposition arrangement  110  dispenses the composition from the accumulator  108  at the same pressure as the pressure within the expandable chamber  109  of the accumulator  108 , without any additional pressure sources. In the cleaning mode, the deposition arrangement  110  may discharge the composition as a continuous pressurized flow, or as a pressurized pulse incrementally dispensed at a predetermined frequency or rate (e.g., every 5 seconds, every 3 seconds, or every 1 second) until the pressure within the accumulator  108  is restored to be within the range between the predetermined threshold value and the predetermined ceiling value. For example, in step  310 , the pressure sensor  106  continues to monitor the pressure of the expandable chamber  109  of the accumulator  108  as the deposition arrangement  110  dispenses the composition from the accumulator  108 . In step  312 , the processing arrangement  112  receives pressure data from step  310  and analyzes the pressure data to determine whether the pressure within the accumulator  108  is within a desired pressure range, in particular, between the predetermined threshold value discussed above, and a predetermined ceiling value, for application of the composition to the keratinous substrate. If the pressure within the accumulator  108  is still in excess of the predetermined ceiling value, the device  100  continues to discharge the composition from the accumulator  108  via the deposition arrangement  110  until the desired pressure is reached, e.g., the pressure falling below the predetermined ceiling value. Once the pressures of the accumulator  108  falls below the predetermined ceiling value, the device  100  resumes operation within method  200 , in particular, continues to steps  208  to  214 , as discussed above. In some embodiments, the deposition arrangement  110  may comprises a plurality of nozzles that may each be individually activated through each iteration of steps  308  to  312 . For example, the processing arrangement  112  may direct the deposition arrangement  110  to discharge the composition via a rotating series of individually activated nozzles until the pressure within the accumulator  108  is restored to be within the range between the predetermined threshold value and the predetermined ceiling value. The collective amount of composition continually dispensed by the deposition arrangement  110  in the cleaning mode may comprise a small portion of a total amount of composition initially charged within the reservoir  102  so the composition is not excessively wasted by the device  100  when operating in cleaning mode. Preferably, the accumulator  108  is suitably configured (e.g., having a suitable size, shape, stiffness and/or pressure) such that the collective amount of composition dispensed by the device  100  in cleaning mode is a small portion (e.g., less than 1%, less than 0.5%, less than 0.3%, or less than 0.1%) of the total amount of composition initially charged within the reservoir  102 . For example, the deposition arrangement  110  dispenses in the cleaning mode a collective amount from about 1 microliter to about 50 microliters, about 3 microliters to about 25 microliters, or from about 5 microliters to about 20 microliters of the composition. 
     The increased cleaning pressure used in method  300  allows the device  100  to dispense the composition at an elevated pressure to assist unclogging of obstructions and/or to purge residual composition in air exposed portions of the deposition arrangement from prior use. The purging of fluid from air exposed portions of the deposition arrangement  110  clears the deposition arrangement  110  of old, air-exposed residual amounts of the composition from prior use, which can accumulate dirt, bacteria, mold and/or other undesirable contaminants during storage of the device  100  between uses. However, the increased cleaning pressure is preferably selected to be a pressure within the same operating pressure range during normal operation within method  200  before continuing use of the device  100  for application of the composition to a keratinous substrate. 
     In one exemplary embodiment, the reservoir  102  is a pressurized canister filled within the composition and a propellant. The pressurized canister may be initially charged with about 5 mL of the composition, which is gradually depleted as the device  100  is continually used. The propellant in this embodiment is nitrogen and pressurizes the composition within the pressurized canister to a pressure from about 12 psi to about 30 psi. In particular, when the canister is filled to 5 mL the nitrogen gas pressurizes the composition to a pressure about 30 psi. As the composition is discharged from the canister, the pressure is gradually reduced to about 12 psi, when the composition is completely emptied from the canister. Therefore, this exemplary pressurized canister can provide a pressurized flow of the composition having at least a pressure of 12 psi to the accumulator  108 . As already discussed above, a first step in the cleaning mode is to supply a pressurized flow of the composition to the accumulator  108 . In particular, the processing arrangement  112  directs the supply valve  104  to open and allow a pressurized flow of the composition to pass therethrough to fill and expand the expandable chamber  109  of the accumulator  108 . The processing arrangement  112  monitors, via the pressure sensor  106 , the pressure of the expandable chamber  109  and directs the supply valve  104  to close once a desired pressure within the expandable chamber  109  is reached. In this example, the supply valve  104  remains open until a pressure of about 12 psi is reached within the expandable chamber  109 . The deposition arrangement  110  in this embodiment may include a plurality of nozzles, preferably 5 nozzles. In a cleaning mode, the processing arrangement  112  directs the deposition arrangement  110  to discharge the composition by activating a single nozzle and individually cycling through each of the plurality of nozzles for each iteration of steps  308  and  312  as discussed above. Each of the nozzles comprises a valve that rapidly opens and closes to release about a pulse of a pressurized spray droplets of the composition. In particular, each valve may open and close within about 0.2 ms to dispense about 5 nanoliters of the composition during each pulse. As the composition is discharged through each of the nozzles, pressure within the expandable chamber  109  of the accumulator  108  incrementally decreases. The processing arrangement  112  continues to cycle through the nozzles to discharge the composition until a desired pressure for normal operation of the device  100  is reached. In this example, the desired operating pressure is about 5 psi, and a collective amount of about 15 microliters of the composition may be dispensed in the cleaning mode. 
     The device  100  is capable of dispensing pressurized composition from the deposition arrangement  110  when it is held in any orientation, whether it is held in an upright configuration or in a flow restricted configuration so long as composition remains within the accumulator  108 . The ability to operate the device  100  in any configuration, including a flow restricted configuration, can be useful to allow flexible manual manipulation of the device across different skin areas on the face of a user to access difficult to for application of the composition. 
     In one exemplary embodiment, the reservoir  102  comprises a storage chamber  150 , a dispenser  159  and a dip tube  156  having a first end  157  submersed within and open to the composition  152  and a second end  161  operably connected to the dispenser  159  for drawing the composition from the first end  157  to the second end  161  and dispensing the pressurized flow via the dispenser  159  when it is activated. However, the dip tube  156  cannot draw the composition from the first end  157  to the second end  161  when the reservoir  102  is inverted or angled relative to the vertical so that the first end  157  of the dip tube  156  is no longer submersed in the composition  152 . As discussed above, the orientation, i.e., whether or not the device  100  is upright or inverted, may be detected by the orientation detector  158 . The orientation detector  158  generates orientation data corresponding to the positioning and/or orientation of the device  100  relative to a vertical position. The processing arrangement  112  receives and analyzes the orientation data to determine whether the device  100  is being held at an orientation (e.g., inverted) in which the first end  157  is no longer submerged in the composition and closes the supply valve  104  when the orientation data indicates that the device  100  in such an orientation. Those skilled in the art will understand that the orientation detector  158  may employ any number of mechanisms in addition to or as an to an accelerometer to detect a condition in which the first end  157  is not submerged in the composition  152  including monitoring a level of fluid in the reservoir  102  and calculating a critical angle based on this amount at which the first end  157  is exposed, monitoring flow through the dip tube  156 , etc. The orientation detector  158  monitors the positioning and/or orientation of the device  100  throughout its operation, including during methods  200  and  300  and provides the orientation data to the processing arrangement  112 . In this exemplary embodiment, when the processing arrangement  112  determines that the device  100  is in a flow restricted configuration (e.g., when the first end  157  of the dip tube  156  is not submerged within the composition  152  within the reservoir  102 ), the supply valve  104  is closed and overrides steps  202 ,  214  and  302  discussed above. When the processing arrangement  112  determines that the device  100  is no longer in the flow restricted configuration (e.g., the device  100  resumes an upright configuration in which the first end  157  is submerged within the composition in the reservoir  102 ), the supply valve  104  is re-opened as determined in steps  202 ,  214  and  302  to refill the accumulator  108  as discussed above. 
     Although the supply valve  104  is closed when the device  100  is in a flow restricted configuration, the device  100  continues to dispense pressurized composition from the accumulator  108  via the deposition arrangement  110  so that use of the device  100  is not interrupted when the device  100  is inverted. The expandable chamber  109  of the accumulator  108  can be suitably sized to store an amount of the composition therein sufficient to permit the device  100  to continue to dispense the composition from the accumulator  108  via the deposition arrangement  110  during a predetermined period of time or over a predetermined number of pressurized pulses, even if the accumulator  108  does not receive any additional supply of the composition from the reservoir  102  during this time. Preferably, the accumulator  108  has a capacity for storing an amount of composition sufficient to continue dispensing the composition from the accumulator  108  via the deposition arrangement  110  over a predetermined period of time or for a predetermined number of pressurized pulses, without the pressure of the expanded chamber of the accumulator  108  falling below the predetermined threshold value or within predetermined margin of error, within which variabilities arc not noticeable when applied to the skin, and do not impact the aesthetic appearance of coverage provided by the composition. For example, the predetermined margin of error may be less than 2 psi, or preferably, less than 1 psi. For example, the device  100  may be capable of dispensing the composition from the accumulator  108  via the deposition arrangement  110 , without any additional supply from the reservoir  102  or any additional pressure sources, for at least 15 seconds, at least 30 second, or at least 1 minute. As another example, the expandable chamber  109  of the accumulator  108  may be sized to be capable of dispensing the composition from the accumulator  108  via the deposition arrangement  110 , without additional supply from the reservoir  102  for at least 50 pressurized pulses, at least  100  pressurized pulses, at least  300  pressurized pulses while maintaining the pressure of the expandable chamber  109  above the predetermined threshold within the predetermined margin of error. 
     The present invention will be further understood by reference to the following Example which is illustrative of the composition, form and method of producing the present invention. It is to be understood that many variations of composition, form and method of producing this would be apparent to those skilled in the art. The following Example, wherein parts and percentages are by weight unless otherwise indicated, are only illustrative. 
     EXAMPLE 
     Example 1 
     Example 1 provides an exemplary embodiment of a device  100  for applying a fluid composition, in particular a pressurized fluid composition, as described above and illustrated in  FIG.  1   . A suitable fluid composition has a viscosity at or about 1 cP (e.g., water) at room temperature. It is also contemplated that the exemplary device of Example 1 may be used with a fluid composition that is more viscous than water. The exemplary device of Example 1 includes a constant pressure liquid source of the fluid composition to be dispensed by the device, set at 30 psi, acting as the reservoir  102 . The liquid source feeds the fluid composition via rigid tubing acting as exemplary conduits  103  to a micro-valve (e.g., G300-G3001000 commercially available from TechElan, LLC) acting as the supply valve  104 . The micro-valve is fluidly connected via a T-shaped connector to a pressure sensor transducer, acting as the pressure sensor  106 , and an exemplary embodiment of the accumulator  108 . The T-shaped connector is connected via additional rigid tubing to the pressure sensor transducer. In Example 1, the pressure sensor transducer is a piezoresistive silicon pressure sensor, such as the board mounted pressure sensors commercially available from Honeywell International Inc. (c.g., sensors designated as SSCMLNT060PGAA5). The exemplary accumulator of Example I is an elastomer tubing, more specifically, silicone tubing. The exemplary accumulator has an elastic portion having a predetermined length that is not structurally supported by other components connecting thereto. The silicone tubing includes commercially available silicone rubber soft tubing, such as, for example, those having a hardness of at or about 50A durometer. A suitable silicone rubber soft tubing is commercially available from McMaster-Carr designated as 2124T3, having an inner diameter at or about 1/16 inch, an outer diameter at or about ⅛ inch, and a wall thickness at or about 1/32 inches. The elastomer tubing is directly connected to a deposition valve, such as a micro-dispensing valve (e.g., G300-150300 commercially available from TechElan, LLC), acting as an exemplary embodiment of the deposition arrangement  110 . The elastomer tubing is cut to length such that at or about 3.75 mm of length is the elastic portion of the elastomer tubing that is not structurally supported by the T-shaped connector or the deposition valve. The exemplary supply and deposition valves in Example 1 are connected to and operably controlled by an exemplary processing arrangement (e.g., LabVIEW system commercially available from National Instruments) according to the following steps:
     A) Start. Open deposition valve for 1 microsecond.   B) Evaluate pressure detected by the pressure sensor:
   If the pressure detected by the pressure sensor is less than 5 psi, then close the deposition valve and open the supply valve for 1 microsecond. Wait 1 microsecond, and return to “Start” in Step A.   If pressure is greater than 5 psi. return to “Start” in Step A.   
   

     The prototype of the exemplary device of Example 1 was constructed and demonstrated full functionality in applying a pressurized fluid composition to a substrate at a constant or substantially constant pressure of about 5 psi. 
     The invention described and claimed herein is not to be limited in scope by the specific embodiments herein disclosed since these embodiments are intended as illustrations of several aspects of this invention. Any equivalent embodiments are intended to be within the scope of this invention. Indeed, various modifications of the invention in addition to those shown and described herein will become apparent to those skilled in the art from the foregoing description. Such modifications are also intended to fall within the scope of the appended claims. All publications cited herein are incorporated by reference in their entirety.