# Patent

## Title
Aerosol antiperspirant compositions, products and methods

## Abstract

An aerosol antiperspirant composition is provided. The aerosol antiperspirant composition includes a propellant having a concentration from 70% to 90% by weight of the aerosol antiperspirant composition and an antiperspirant composition. The antiperspirant composition includes one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, an antiperspirant active particulate, one or more non-antiperspirant active particulates that are substantially inert, and a silicone sum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition.

## Background
TECHNICAL FIELD
One aspect of the invention relates generally to antiperspirant compositions. Another aspect of the invention relates generally to spray devices containing an antiperspirant composition and a propellant. Yet another aspect of the invention relates generally to methods of using antiperspirant spray devices.
BACKGROUND
Body odor may be generated in the area under the arms due to a high concentration of sweat glands. While perspiration is odorless, it contains natural oils that can be nutrient source for bacteria living on the skin. These bacteria interact with the natural oils, converting them into odor producing compounds. Antiperspirant compositions contain an active, such as an aluminum salt, that reacts with the electrolytes in perspiration to form a plug in the ducts of sweat glands. The plugs prevent perspiration from exiting the duct, thereby depriving the bacteria of water and a food source. Antiperspirant compositions may be applied to the skin in either a contact type product form, e.g., a stick or roll-on, or non-contact type product form, such as an aerosol spray. Aerosol spray devices that dispense an antiperspirant composition are known in the art. Various examples are described in U.S. Pat. No. 4,152,416; U.S. Pat. No. 4,806,338; U.S. Pat. No. 4,840,786; U.S. Pat. No. 4,904,463; U.S. Pat. No. 4,935,224; U.S. Pat. No. 5,298,236; U.S. Pat. No. 5,605,682; U.S. Pat. No. 5,814,309; U.S. Pat. No. 7,815,899; EP 674,899; WO 96/04884; WO 2004/014330; and WO 2007/001842.
Many aerosol antiperspirant users desire a product that minimizes the appearance of residue on the skin, has a dry rather than wet feel, has rapid perceived drying, is not sticky, and provides a cool/fresh feeling at time of application. Other desired product attributes include providing long lasting wetness and/or odor protection, an easily portable form for purses or small bags (as some users may apply the antiperspirant composition more than once a day) and minimizing the gassy cloud that forms during dispensing. While the relative importance/desirability of these characteristics may vary by geographical region and gender and not all users desire all or the same set of characteristics, a generally universal desire among aerosol antiperspirant users appears to exist for a dry rather than wet feel, minimizing the appearance of residue, and/or providing long lasting wetness/odor protection or efficacy.
While some currently marketed aerosol spray devices may provide at least some of these characteristics to varying degrees, there are often tradeoffs involved. For example, many currently available aerosol antiperspirant compositions also incorporate a volatile liquid (e.g., cyclopentasiloxane) as a carrier for the antiperspirant active. The volatile liquid evaporates following application to the skin, resulting in a dry skin feel, but sometimes leaves behind a visible residue (the antiperspirant active) that is subject to flaking and/or transfer to clothing. Flaking (or transfer) of the antiperspirant active may also reduce antiperspirant efficacy. Further in some cases the cyclopentasiloxane may not be deposited well by products containing propellant levels between 75% and 90%, which may further exacerbate the amount of visible residue and flaking mentioned above. Therefore, there is continuing desire to provide improved aerosol antiperspirant compositions and products.
SUMMARY OF THE DISCLOSURE
In accordance with one aspect, an aerosol antiperspirant composition is provided. The aerosol antiperspirant composition includes a propellant having a concentration from 70% to 90% by weight of the aerosol antiperspirant composition and an antiperspirant composition. The antiperspirant composition includes one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, an antiperspirant active particulate, one or more non-antiperspirant active particulates that are substantially inert, wherein the one or more non-antiperspirant active particulates that are substantially inert have a concentration from 10% to 30% by weight of the antiperspirant composition. The antiperspirant composition may have a total particulate concentration from 30% to about 60% by weight of the antiperspirant composition.
In accordance with other aspects, the invention may also be described by any one of the following paragraphs.
An aerosol antiperspirant composition, may comprise:

    
    
        a propellant having a concentration from 70% to 95%, preferably from 70% to 90%, more preferably from 80% to 90%, by weight of the aerosol antiperspirant composition;
        an antiperspirant composition comprising:
        
            one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, more preferably from 40% to 50% by weight of the antiperspirant composition;
            an antiperspirant active particulate;
            one or more non-antiperspirant active particulates that are substantially inert, wherein the non-antiperspirant active particulates are selected from the group consisting of native starches, particulate fragrance materials, hydrophobically modified starches and combinations thereof; and
            a silicone gum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition.
        
        
    
    


An aerosol antiperspirant composition, may also comprise:

    
    
        a propellant having a concentration from 70% to 95%, by weight of the aerosol antiperspirant composition;
        an antiperspirant composition comprising:
        
            one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition;
            an antiperspirant active particulate;
            one or more non-antiperspirant active particulates that are substantially inert, having a concentration from 10% to 30%, by weight of the antiperspirant composition; and
            wherein the antiperspirant composition has a total particulate concentration from 30% to about 60%, by weight of the antiperspirant composition.
        
        
    
    


In another aspect an aerosol antiperspirant composition, may also comprise:

    
    
        a propellant having a concentration from 70% to 95%, preferably from 87% to 90%, more preferably from 80% to 90%, by weight of the aerosol antiperspirant composition;
        an antiperspirant composition comprising:
        
            one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, more preferably from 40% to 50% by weight of the antiperspirant composition;
            an antiperspirant active particulate;
            one or more non-antiperspirant active particulates that are substantially inert;
            a silicone gum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition; and
            wherein the amount of total particulates in the antiperspirant composition is from 30% to 50% by weight of the antiperspirant composition.
        
        
    
    


An aerosol antiperspirant composition, may also comprise:

    
    
        a propellant having a concentration from 70% to 95%, preferably from 70% to 90%, more preferably from 80% to 90%, by weight of the aerosol antiperspirant composition;
        an antiperspirant composition comprising:
        
            one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, more preferably from 40% to 50% by weight of the antiperspirant composition;
            an antiperspirant active particulate;
            one or more non-antiperspirant active particulates that are substantially inert;
            a silicone gum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition; and
        
        
        wherein the amount of the one or more non-antiperspirant active particulates is from 1% to 25% by weight of the antiperspirant composition.
    
    


An aerosol antiperspirant composition, may also comprise:

    
    
        a propellant having a concentration from 70% to 95%, preferably from 70% to 90%, more preferably from 80% to 90%, by weight of the aerosol antiperspirant composition; an antiperspirant composition comprising:
        
            one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, more preferably from 40% to 50% by weight of the antiperspirant composition;
            an antiperspirant active particulate;
            one or more non-antiperspirant active particulates that are substantially inert;
            a silicone gum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition; and
        
        
        wherein the ratio of the antiperspirant active particulate concentration to total particulate concentration is from 0.1 to 0.75.
    
    


An aerosol antiperspirant composition, may also comprise:

    
    
        a propellant having a concentration from 70% to 95%, preferably from 70% to 90%, more preferably from 80% to 90%, by weight of the aerosol antiperspirant composition;
        an antiperspirant composition comprising:
        
            one or more liquid materials, wherein the one or more liquid materials comprise one or more non-volatile silicone fluids having a concentration from 40% to about 70% by weight of the antiperspirant composition, more preferably from 40% to 50% by weight of the antiperspirant composition;
            an antiperspirant active particulate;
            one or more non-antiperspirant active particulates that are substantially inert; a silicone gum; and
        
        
        wherein the concentration of the propellant is from 70% to 80% and the concentration of the silicone gum is from 0.1% to 0.6%.
    
    


In certain aspects the aerosol antiperspirant composition has a ratio of the concentration of the total liquid materials to the concentration of the total particulate materials is from about 0.6 to about 1.2.
The antiperspirant composition may also have a total particulate concentration from 30% to about 60%, in another aspect from 30% to 50% and/or from 40% to 50%, by weight of the antiperspirant composition. The one or more non-antiperspirant active particulates may comprise from 1% to 25% by weight of the antiperspirant composition. The ratio of the antiperspirant active particulate concentration to the total particulate concentration may be less than or equal to about 0.75 and/or the ratio of the antiperspirant active particulate concentration to total particulate concentration may be from 0.1 to 0.75. In another aspect the one or more non-antiperspirant active particulates that are substantially inert may have a concentration from 10% to 30%, in an alternative aspect from 10% to 25%, by weight of the antiperspirant composition.
In one aspect the one or more liquid materials of the antiperspirant composition consist essentially of one or more non-volatile silicone fluids. The antiperspirant composition may also comprise one or more liquid materials that comprise less than 10% by weight of volatile silicone fluids and/or the antiperspirant composition is substantially or completely free of volatile silicone fluids. Moreover, the one or more non-volatile silicone fluids may consist essentially of a polydimethyl siloxane fluid having a viscosity of 50 centistokes.
In another aspect the aerosol antiperspirant composition further comprises a particulate fragrance material having a concentration from about 0.25% to about 5% by weight of the antiperspirant composition and/or a liquid fragrance material having a concentration less than 4% by weight of the antiperspirant composition.
In another aspect the aerosol antiperspirant composition further comprises a silicone gum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition and/or from 0.1% to 0.6%, in another aspect from 0.25% to 0.5% by weight of the antiperspirant composition.
In an aspect the aerosol antiperspirant composition comprises one or more non-antiperspirant active particulates that are selected from the group consisting of particulate fragrance materials, native starches and combinations thereof.
In other aspects the aerosol antiperspirant composition may have a viscosity greater than 3,000 centipoises and/or the antiperspirant composition may be substantially or completely free of quartenary ammonium functional silicones. In other aspects the antiperspirant composition may be substantially or completely free of functionalized siloxanes capable of reacting with the antiperspirant active particulates via an acid base or chelation reaction.
In other aspects the propellant concentration may be from 70% to 80%, and/or 80% to 90% and the concentration of the silicone gum is from 0.3% to 1.5%, preferably 0.5% to 1%, by weight of the antiperspirant composition.
A product, comprising a reservoir (118), an actuator (110) comprising an actuator orifice (112), and a valve in fluid communication with the actuator orifice (112) and the reservoir, the reservoir may store the aerosol antiperspirant composition according to the invention herein.



BRIEF DESCRIPTION OF THE DRAWINGS
While the specification concludes with claims, it is believed that the same will be better understood from the following description taken in conjunction with the accompanying drawings wherein like numbers illustrate like elements throughout the views and in which:
FIG. 1 is a graph showing % Deposition and Spray Pattern Diameter as a function of gum concentration at 85% propellant;
FIG. 2 is a cross-sectional side view of one non-limiting example of a spray device comprising an actuator, a valve assembly and a reservoir containing a liquid propellant, a gaseous propellant and an antiperspirant composition; and
FIG. 3 is a photograph of three antiperspirant compositions, each having a different total particulate concentration, after spraying on a skin mimic material.



DETAILED DESCRIPTION
A spray device, container, composition, propellant, etc. may comprise, consist essentially of, or consist of, various combinations of the materials, features, structures, and/or characteristics described herein.
Reference within the specification to “embodiment(s)” or the like means that a particular material, feature, structure and/or characteristic described in connection with the embodiment is included in at least one embodiment, optionally a number of embodiments, but it does not mean that all embodiments incorporate the material, feature, structure, and/or characteristic described. Furthermore, materials, features, structures and/or characteristics may be combined in any suitable manner across different embodiments, and materials, features, structures and/or characteristics may be omitted or substituted from what is described. Thus, embodiments and aspects described herein may comprise or be combinable with elements or components of other embodiments and/or aspects despite not being expressly exemplified in combination, unless otherwise stated or an incompatibility is stated.
In all embodiments, all percentages are by weight of the antiperspirant composition (or formulation), unless specifically stated otherwise. All ratios are weight ratios, unless specifically stated otherwise. All ranges are inclusive and combinable. The number of significant digits conveys neither a limitation on the indicated amounts nor on the accuracy of the measurements. All numerical amounts are understood to be modified by the word “about” unless otherwise specifically indicated. Unless otherwise indicated, all measurements are understood to be made at approximately 25° C. and at ambient conditions, where “ambient conditions” means conditions under about 1 atmosphere of pressure and at about 50% relative humidity. The term “molecular weight” or “M.Wt.” as used herein refers to the number average molecular weight unless otherwise stated.
The term “antiperspirant composition” refers to any composition containing an antiperspirant active and which is intended to be sprayed onto skin, exclusive of a propellant.
The term “antiperspirant efficacy” refers to the amount of wetness protection provided by application of an antiperspirant composition to an underarm area (or axillia) by a spray device. Antiperspirant efficacy may be quantified by the amount (mg) of sweat collected following exposure to a hot room compared to a baseline amount.
The term “bulking or suspending material” refers to a material which is intended to reduce settling of a particulate from a liquid and/or reduce the severity of particulate caking post settling.
The term “deposition efficiency” refers to the percentage of a material (e.g., antiperspirant active, fragrance material, antiperspirant composition, etc.) that is deposited on a target surface compared to the amount of material that exits a spray device.
The term “particulate” refers to a material that is solid or hollow or porous (or a combination thereof) and which is substantially or completely insoluble in the liquid materials of an antiperspirant composition.
The term “propellant” refers to one or more gases that are used to pressurize the antiperspirant composition to facilitate egress of the antiperspirant composition from the container. Some propellants may be a mixture of gases (e.g., A-46 which may be a mixture of isobutane, butane and propane). A propellant may be in the form of a liquid (i.e., a liquefied gas) when under pressure within the reservoir of a spray device. In addition, a propellant may be in its gaseous state within the head space of the reservoir. A propellant may be present in both a liquefied form and its gaseous state within the reservoir. Unless specified otherwise (e.g., liquid propellant or gaseous propellant), the term propellant is intended to encompass the liquefied form and the gaseous state individually and collectively.
The term “substantially free of” refers to an amount of a material that is less than 1%, 0.5%, 0.25%, 0.1%, 0.05%, 0.01%, or 0.001% by weight of an antiperspirant composition. “Free of” refers to no detectable amount of the stated material, ingredient or thing.
The term “total fill” refers to the total amount of materials added to or stored within a reservoir(s) of a container. For example, total fill includes the propellant and antiperspirant composition stored within a spray device after completion of filling and prior to first use.
The term “viscosity” means dynamic viscosity (measured in centipoise, cPs, or Pascal-second, Pa·s) or kinematic viscosity (measured in centistokes, cSt, or m2/s) of a liquid at approximately 25° C. and ambient conditions. Dynamic viscosity may be measured using a rotational viscometer, such as a Brookfield Dial Reading Viscometer Model 1-2 RVT available from Brookfield Engineering Laboratories (USA) or other substitutable model as known in the art. Typical Brookfield spindles which may be used include, without limitation, RV-7 at a spindle speed of 20 rpm, recognizing that the exact spindle may be selected as needed by one skilled in the art. Kinematic viscosity may be determined by dividing dynamic viscosity by the density of the liquid (at 25° C. and ambient conditions), as known in the art.
I. PROPELLANTS
A spray device comprises a propellant stored in one or more reservoirs of the container. The propellant may be stored in the same reservoir as an antiperspirant composition or a separate reservoir, although it is preferred that the propellant is stored within the same reservoir as the antiperspirant composition. The propellant may be present in a liquefied form that is miscible with liquid carriers of the antiperspirant composition as well as gaseous state within a head space of the reservoir. The liquid propellant and the antiperspirant composition form a mixture that travels through the container, eventually exiting the container where the liquid propellant vaporizes to from a spray. The propellant may have a concentration from about 70% to about 90% or 95% or from about 70% to about 80% or from about 80% to about 90%. Generally, as propellant concentration increases through these higher concentrations, the discharge may tend be more “gassy” possibly resulting in less deposition of the antiperspirant composition on the target surface as well as a wider spray pattern.
A wide variety of propellants may be used with the spray devices and antiperspirant compositions described herein, although in some embodiments the spray device is substantially free of compressed gas propellants such as nitrogen, air and carbon dioxide. Some suitable propellants may have a boiling point (at atmospheric pressure) within the range of from about −45° C. to about 5° C. Some suitable propellants may include chemically-inert hydrocarbons such as propane, n-butane, isobutane and cyclopropane, and mixtures thereof, as well as halogenaed hydrocarbons such as dichlorodifluoromethane (propellant 12) 1,1-dichloro-1,1,2,2-tetrafluoroethane (propellant 114), 1-chloro-1,1-difluoro-2,2-trifluoroethane (propellant 115), 1-chloro-1,1-difluoroethylene (propellant 142B), 1,1-difluoroethane (propellant 152A), dimethyl ether and monochlorodifluoromethane, and mixtures thereof. Some propellants suitable for use include, but are not limited to, A-46 (a mixture of isobutane, butane and propane), A-31 (isobutane), A-17 (n-butane), A-108 (propane), AP70 (a mixture of propane, isobutane and n-butane), AP40 (a mixture of propane, isobutene and n-butane), AP30 (a mixture of propane, isobutane and n-butane), HFO1234 (trans-1,3,3,3-tetrafluoropropene) and 152A (1,1 difluoroethane).
II. ANTIPERSPIRANT COMPOSITIONS
A. Antiperspirant Composition Viscosity
In some embodiments, it may be desirable for the viscosity of the antiperspirant composition to be from about 1,000 centipoise, 2,000 centipoise, or 3,000 centipoise to about 50,000 centipoise 40,000 centipoise, or 30,000 centipoise, or 20,000 centipoise, or 10,000 centipoise, or 7,000 centipoise, 5,000 centipoise or 4,000 centipoise at 25° C. (1 centipose being equal to 1×10−3 Pa·s). It is believed that a viscosity lower than 1,000 centipoise may lead to an antiperspirant composition, which when spayed, results in a runny or drippy effect on skin. This may be perceived by a user as having a wet rather than dry feel. For comparison, roll-on type antiperspirant compositions often have viscosities below 1,000 centipoise, because the roll-on applicator utilizes a roller ball to apply a thin film of the antiperspirant composition thereby minimizing a runny or drippy effect.
By way of illustration, three antiperspirant compositions (Examples 1, 2 and 3) were prepared, each having a different total particulate concentration and, therefore, viscosity. Example 1 comprised 30% total particulates, and Example 2 comprised 37% total particulates while Example 3 comprised 44% total particulates. The composition of Example 1 had a viscosity of about 950 centistokes, the composition of Example 2 had a viscosity of about 2,050 centistokes while the composition of Example 3 had a viscosity of about 5,500 centistokes. Approximately 0.1 ml of each antipersprirant composition was applied to a skin mimic using a syringe. The skin mimic samples were then positioned vertically for approximately 10 seconds. FIG. 3 is a photograph taken of the skin mimic samples after approximately 10 seconds in the vertical position. It can be seen that the composition of Example 1 was very “runny” and had an average drip length more than triple that of the composition of Example 3. The antiperspirant composition of Example 1 approximated that of a roll-on type antiperspirant product and is believed to have poor aesthetics for use in an aerosol antiperspirant product. The antiperspirant composition of Example 3 exhibited good aesthetics and is believed to be acceptable for use in an aerosol antiperspirant product. An antiperspirant composition should be flowable so that it may be sprayed effectively from a spray device. Therefore in certain aspects, the aerosol antiperspirant composition may be devoid of sufficient concentrations and/or substantially free of ingredients that provide thickened stick or gel type of rheology in antiperspirant stick or gel products. Some common agents which may be excluded in sufficient amounts include hydrogenated castor oil, solid paraffins, silicone waxes, and mixtures thereof.
B. Non-Volatile Silicone Fluids
The antiperspirant compositions comprise one or more non-volatile silicone fluids. The non-volatile silicone fluid may function as the primary or principal liquid carrier for the antiperspirant active. As used herein, the term “non-volatile” refers to a material that has a boiling point above 250° C. (at atmospheric pressure) and/or a vapor pressure below 0.1 mm Hg at 25° C. Conversely, the term “volatile” refers to a material that has a boiling point less than 250° C. (at atmospheric pressure) and/or a vapor pressure about 0.1 mm Hg at 25° C. Incorporating a non-volatile silicone fluid in an antiperspirant composition may provide several benefits. First, non volatile silicone fluids can be more effectively deposited on the skin than volatile silicone fluids from aerosol antiperspirant compositions containing high levels of propellant, such as greater than 70% or 80% propellant. Deposition of high concentrations of a non-volatile carrier fluid in the antiperspirant composition is believed to reduce visible white residue at application, reduce visible white residue throughout the day and reduce antiperspirant composition transfer to clothes while dressing. This can be illustrated by comparing the deposition of liquids from two test samples. The first test sample comprises 85% A 46 propellant and 15% cyclopentasiloxane by weight of the antiperspirant composition, and the second comprises 85% A 46 and 15% of 50 centistoke dimethicone by weight of the antiperspirant composition. Both test samples used the same valve and actuator combination. The first test sample comprising cyclopentasiloxane had a deposition efficiency of about 24% and the second test sample comprising 50 centistoke dimethicone had a deposition efficiency of about 42%. This represents a 65% improvement in deposition by replacing the cyclopentasilcone with 50 cst dimethicone. While not being bound by any theory, it is believed that the lower deposition of antiperspirant composition comprising cyclopentasiloxane may result from both inherent volatility of the volatile silicone fluid which can allow it to begin evaporating prior to deposition and a higher solubility of the antiperspirant composition in the propellant resulting in an increase in the evaporation rate as the antiperspirant composition is co-vaporized with the propellant as both are expelled from the container. Second, incorporating a non-volatile silicone fluid may increase the substantivity of the antiperspirant composition on skin, thereby potentially increasing antiperspirant efficacy, as the antiperspirant composition may form a film that more readily adheres to skin rather than flaking off or transferring to clothing throughout the day. Third, incorporating a non-volatile silicone fluid may also decrease the propensity for a visible residue to appear on skin (compared to using a volatile silicone fluid), as the non-volatile silicone fluid does not evaporate thereby leaving behind the white antiperspirant active as a visible residue. However, incorporating a non-volatile silicone fluid is not without potential tradeoffs. A perception of wetness post application (which may be undesirable for some consumers) is one tradeoff that may be associated with high concentrations of a non-volatile silicone fluid in an antiperspirant composition.
The total concentration of non-volatile, silicone fluids may be from about 30%, 35%, 40%, 45%, 50% to about 70%, 65%, 60%, 55% or 50% by weight of an antiperspirant composition. In some embodiments, the total concentration of non-volatile, silicone fluids may be from about 35% or 45% to about 55% by weight of an antiperspirant composition. The liquid materials of the antiperspirant composition may consist essentially of or primarily comprise a non-volatile, silicone fluid(s). Some non-volatile, silicone fluids that may be used include, but are not limited to, polyalkyl siloxanes, polyalkylaryl siloxanes, and polyether siloxane copolymers, and mixtures thereof. Some preferred non-volatile silicone fluids may be linear polyalkyl siloxanes, especially polydimethyl siloxanes (e.g., dimethicone). These siloxanes are available, for example, from Momentive Performance Materials, Inc. (Ohio, USA) under the tradename Element 14 PDMS (viscosity oil). Silicones Fluids from Dow Corning Corporation (Midland, Mich., USA) available under the trade name Dow Corning 200 Fluid series (e.g., 3 to 350 centistokes). Other non-volatile silicone fluids that can be used include polymethylphenylsiloxanes. These siloxanes are available, for example, from the General Electric Company as SF 1075 methyl phenyl fluid or from Dow Corning as 556 Fluid. A polyether siloxane copolymer that may be used is, for example, a dimethyl polyoxyalkylene ether copolymer fluid. Such copolymers are available, for example, from the General Electric Company as SF-1066 organosilicone surfactant. The non-volatile, silicone fluid may have an average viscosity from about 3 centistokes, 5 centistokes, 10 centistokes, 20 centistokes, or 50 centistokes to about 350 centistokes, 200 centistokes, 100 centistokes, 50 or 30 centistokes at 25° C. (1 centistoke being equal to 1×10−6 m2/s). In some specific embodiments, the silicone fluid may have a viscosity from about 5 centistokes to about 100 centistokes or 5 centistokes to about 50 centistokes or about 5 centistokes to about 30 centistokes. Higher viscosity non-volatile silicone fluids (e.g., greater than 100 centistokes or 200 centistokes or 350 centistokes) are preferably mixed with lower viscosity, non-volatile silicone fluids to achieve an appropriate antiperspirant composition viscosity in combination with the concentration of particulates. High viscosity, non-volatile silicone fluids (e.g., greater than 100, 200, or 350 centistokes) may comprise less than 25% by weight of an antiperspirant composition.
In some instances, the non-volatile silicone fluid is a polydimethylsiloxane fluid (also commonly referred to as dimethicone). It will be appreciated that a polydimethylsiloxane fluid may be further characterized by, optionally, its viscosity or its molecular weight or its formula or a combination thereof. In some instances, the polydimethylsiloxane fluid may have the following characteristics:









TABLE 1






Approximate 
Approximate Average 



Molecular
Number of Monomer Units 


Viscosity
Weight1
in the Polymers

















 3 Centistokes
500
6


 5 Centistokes
800
9


 10 Centistokes
1200
13


 20 Centistokes
2000
27


 30 Centistokes
2600
35


 50 Centistokes
3800
50


100 Centistokes
6000
80


200 Centistokes
9400
125


350 Centistokes
13,700
185





1The compositions of Examples 1 to 24, to the extent they contained a dimethicone fluid, were formulated utilitizing a Dow Corning DC200 series fluid, which is believed to have had average molecule weights and average number of monomer subunits falling within the approcximate values of above-described table.






The polydimethylsiloxane fluid may have the following formula (II):

M-DX-M

wherein M is (CH3)3SiO and D is 2CH3(SiO) and X is equal to the average number of monomer units (see, e.g., Table 1) in the polymer minus 2. In some embodiments, X may be from about 6 to about 185, from about 9 to about 125, from about 9 to about 80, from about 9 to about 50, from about 13 to about 50 or from about 27 to about 50. In other embodiments, X may be from about 6 to about 35, from about 9 to about 35 or from about 13 to about 35. The term “approximate” as used in Table 1 refers to ±10% of a given value.

While a wide variety of non-volatile silicone fluids or oils may be used in an antiperspirant composition, in some instances it may be desirable for the non-volatile silicone fluid(s) to consist essentially of or consist of or consist primarily of non-functionalized silicone fluids. In some embodiments, it may be further desirable for the non-volatile silicone fluid(s) to be substantially or completely free of non-functionalized siloxanes capable of reacting with the antiperspirant active via an acid-base reaction or a chelation reaction. This is in contrast to, for instance, U.S. Pat. No. 4,806,338 which proposes the use of functionalized siloxanes. Functionalized siloxanes may in some instances be disadvantageous in that they may react with the antiperspirant active, either via an acid-base reaction in the case of aminofunctional silicones, which are Lewis bases (the antiperspirant actives are Lewis acids), or via a chelation reaction (in the case of the carboxy functional silicones), which reactions can reduce the efficacy of the antiperspirant active. In addition, functional silicones of the type taught by U.S. Pat. No. 4,806,338 may have reduced solubility in the propellant (and vice versa) which may give rise to inhomogeneity in the product with resultant inhomogeneity of deposition on skin.
C. Liquid Fragrance Materials
An antiperspirant composition may also optionally comprise one or more liquid fragrance materials. Liquid fragrance materials are typically a mixture of perfume or aromatic components that are optionally mixed with a suitable solvent, diluent or carrier. Some suitable solvents, diluents or carriers for the perfume components may include ethanol, isopropanol, diethylene glycol monoethyl ether, dipropylene glycol, diethyl phthalate, triethyl citrate, isopropyl myristate and mixtures thereof. An antiperspirant composition may comprise from about 0.5%, 0.75%, 1%, 2%, 3% or 4% to about 10%, 8%, 6%, or 4%, 3% or 2% by weight of a liquid fragrance material.
The perfume component may be any natural or synthetic perfume component known to one skilled in the art of creating fragrances including, but not limited to, essential oils, citrus oils, absolutes, resinoids, resins, concretes, etc., and synthetic perfume components such as hydrocarbons, alcohols, aldehydes, ketones, ethers, acids, esters, acetals, ketals, nitriles, etc., including saturated and unsaturated compounds, aliphatic, carbocyclic and heterocyclic compounds. Some non-limiting examples of perfume components include: geraniol, geranyl acetate, linalool, linalyl acetate, tetrahydrolinalool, citronellol, citronellyl acetate, dihydromyrcenol, dihydromyrcenyl acetate, tetrahydromyrcenol, terpineol, terpinyl acetate, nopol, nopyl acetate, 2-phenylethanol, 2-phenylethyl acetate, benzyl alcohol, benzyl acetate, benzyl salicylate, benzyl benzoate, styrallyl acetate, amyl salicylate, dimethylbenzyl carbinol, trichloromethylphenyl-carbinyl acetate, p-tert.butyl-cyclohexyl acetate, isononyl acetate, vetiveryl acetate, vetiverol, alpha-n-amylcinammic aidehyde, alpha-hexylcinammic aldehyde, 2-methyl-3-(p-tert.butylphenyl)-propanol, 2-methyl-3-(p-isopropylphenyl)-propanal, 3-(p-tert.butylphenyl)-propanal, tricyclodecenyl acetate, tricyclodecenyl propionate, 4-(4-hydroxy-4-methylpentyl)-3-cyclohexene carbaldehyde, 4-(4-methyl-3-pentenyl)-3-cyclohexene carbaldehyde, 4-acetoxy-3-pentyltetrahydropyran, methyldihydrojasmonate, 2-n-heptylcyclopentanone, 3-methyl-2-pentylcyclopentanone, n-decanal, 9-decenol-1, phenoxyethyl isobutyrate, phenyl-acetaldehyde dimethyl acetal, phenylacetaldehyde diethyl acetal, geranonitrile, citronellonitrile, cedryl acetate, 3-isocamphylcyclohexanol, cedryl methyl ether, isolongifolanone, aubepine nitrile, aubepine, heliotropine, coumarin, eugenol, vanillin, diphenyl oxide, hydroxycitronellal, ionones, methylionones, isomethylionones, irones, cis-3-hexenol and esters thereof, indane musk fragrances, tetralin musk fragrances, isochroman musk fragrances, macrocyclic ketones, macrolactone musk frangrances, ethylene brassylate, aromatic nitro-musk fragrances. Some perfume components are also described in Arctander, Perfume and Flavour Chemicals (Chemicals), Vol. I and II (1969) and Arctander, Perfume and Flavour Materials of Natural Origin (1960).
D. Other Liquid Materials
While it may be desirable for the liquid materials of the antiperspirant composition to consist essentially of or be primarily formed from non-volatile silicone fluids, it is contemplated that other liquid materials may be optionally included in an antiperspirant composition. The liquid materials of the antiperspirant composition may comprise less than 30%, 20%, 10%, or less than 5% by weight of liquid materials other than non-volatile, silicone fluids. Said in another way, the liquid materials of the antiperspirant composition may comprise more than 70%, 75%, 80%, 85%, 90% or about 100% by weight of non-volatile silicone fluids.
It is believed that an antiperspirant composition whose liquid materials comprise too much of a volatile silicone fluid may lead to an increased propensity for the appearance of a residue due to the evaporation of the volatile silicone fluid. An antiperspirant composition may comprise less than 10%, 5%, 1%, or 0.5% by weight of a volatile silicone fluid. An antiperspirant composition may be substantially or completely free of a volatile silicone fluid.
An antiperspirant composition may optionally comprise one or more silicone gums. The term “gum” is used to refer to a material that has a viscosity within the range from about 100,000 to about 100 million centistokes at 25° C. and which is slowly flowable, as opposed to a rigid solid, which is not flowable, or a liquid, which is too flowable. Silicone gum materials are blends of a silicone gum and a diluents, wherein the diluents reduces the viscosity of the blend. Some common diluents can include but are not limited to 5 centistoke dimethicone, 50 centistoke dimethicone, 100 centistoke diemthicone or cyclopentasiloxane. The silicone gum may comprise high viscosity polydimethylsiloxanes with terminal methyl (e.g., dimethicone) or hydroxyl (e.g., dimethiconol) groups. Silicone gums may have a molecular weight from 100,000 Daltons greater than 2,000,000 Daltons. The viscosity of the silicone gums (without a diluents) may range from 300,000 centistokes to greater than 2,500,000 centistokes or higher compared to the viscosity of silicone gum materials (inclusive of diluents) which may be less than 10,000 centistokes. Some examples of silicone gums and silicone gums materials include, but are not limited to, quaternary ammonium functional silicones such as DC7-6030 available from Dow Corning and 34720, 34749, 34731, 33134, SF-96, SF-1066, SF18 (350), SE30 and SE32 available from General Electric.
A silicone gum (or silicone gum material) may be added to an antiperspirant composition to further increase deposition and/or substantivity of the antiperspirant composition and/or increase the drop size of the aerosol spray particles. The improvement in deposition can be illustrated by evaluating the deposition of a test sample comprising 85% A46 propellant, 14.64% 50 centistoke dimethicone, and 0.36% DC1503 (note this is made by mixing 97% 50 cst dimethicone with 3% DC1503, which contains 12% silicone gum, and then adding that mixture to the propellant at a 15%). Deposition testing of this sample using the same valve and accuator as the aforementioned samples showed a deposition efficiency of about 58%. This represents a 38% improvement in deposition versus the aforementioned test sample compring only 50 cst dimethicone and a more than 100% improvement over the sample comprising only cyclopentasiloxane. Maximizing liquid deposition in the test sample comprising a high concentration of a non-volatile silicone fluid and a high propellant concentration is desirable not only to reduce visible white but also to reduce potential inhalation hazards. Volatile silicones, such as cyclopentasiloxane, may be removed from the lung via exhaling while nonvolatile materials are less likely to be removed by the mechanism. As such it is desirable to limit inhalable non-volatile silicone materials by increasing the deposition efficiency via the addition of silicone gum.
However, formulating an antiperspirant composition with a silicone gum in combination with relatively high concentrations of a non-volatile silicone fluid and/or relatively high concentrations of total particulates may involve a number of tradeoffs. For example, too much of a silicone gum may dramatically increase viscosity of the antiperspirant composition and the risk of clogging of the container actuator and/or valve, particularly where there is already a relatively high concentration of total particulates. Still further, too much of a silicone gum may reduce the diameter of the spray making it more difficult for a user to achieve complete coverage of an axillia (typically a 7.5 cm×12.5 cm area) during application as well as potentially creating regions of high antiperspirant composition dosage, thereby potentially impacting skin feel. Further, some silicone gums, such as the quartenary ammonium functional silicones described in U.S. Pat. No. 7,815,899 may have an undersirable odor (e.g., a fish-like odor) associated therewith, which may then be imparted to an antiperspirant composition in some instances.
Examples 4 to 8 illustrate the effect that silicone gum concentration may have on spray pattern and deposition (FIG. 1) at higher propellant and particulate concentrations. The antiperspirant compositions of Examples 4 to 8 comprised different concentrations of a silicone gum material (12% dimethiconol in dimethicone), ranging from 1% (Example 4) to 12% (Example 8) by weight of the antiperspirant composition. The antiperspirant compositions were sprayed on a black paperboard and the spray pattern diameter and characteristics were noted. As can be see in FIG. 1 there is a decrease in spray pattern diameter with increasing gum level. It is believed that the spray pattern produced by Example 8 is poor for use in an aerosol antiperspirant product, while the spray patterns of Examples 5, 6 and 7 are acceptable. The spray patterns of Examples 4 and 7 were marginally acceptable. Different propellants (e.g., with a lower vapor pressure, such as A-17) might improve the spray pattern of Example 4 while Example 8 might improve with an increase in propellant to, for example 90%. As also can be seen in FIG. 1, deposition increases with increasing gum concentration. However, levels of DC1503 greater than 9% (1.08% gum) show limited improvement and significant degradation of the spray pattern. At higher propellant levels, such as 90%, higher gum concentration might provide a significant deposition enhancement without degradation of the spray pattern. Furthermore, levels below 0.3 show limited relatively low deposition at 85% propellant but could provide a significant deposition enhancement if the propellant were reduced to 70 or 80%.
Generally, it is believed that the concentration of the silicone gum may be increased as propellant concentration increases, all other variables being equal. Conversely, it is believed that as the amount of particulates increases, the concentration of the silicone gum should be decreased as the amount of particulates increases, all other variables being equal. This is believed particularly true within the particulate range of 40% to 60% by weight of the antiperspirant composition, as mounding of the antiperspirant composition may result. Without intending to be bound by any theory, the following Table is believed to balance these competing considerations for the most preferred propellant ranges of 70% to 90%. Above 90% propellant, it is believed that up to 1.5% silicone gum would also be acceptable.
















Total 




Propellant 
Particulate
Silicone Gum



Concentration
Concentration
Concentration









70% to 80%
40% to 50%
about 0.1% to about 0.6%



70% to 80%
50% to 60%
about 0.1% to about 0.4%



80% to 90%
40% to 50% 
0.3% to 1.5%, preferably 





about 0.3% to about 1%



80% to 90%
50% to 60% 
0.3% to 1%, preferably 





about 0.3% to about 0.7%










Given the one or more potential challenges associated with incorporating a gum and more particularly a silicone gum, an antiperspirant composition may have a concentration of a silicone gum from about 0.1%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7% or 0.8% to about 1.5%, 1.25%, 1%, 0.9%, 0.8%, 0.7%, 0.65, 0.5%, or 0.4% by weight of the antiperspirant composition. In some instances, the most preferred concentration of silicone gum by weight of the antiperspirant composition is from about 0.3% to about 0.8% in order to balance pattern diameter/quality with deposition, as previously discussed for example with respect to FIG. 1 at 85% propellant concentration. In some instances, the antiperspirant composition may have from about 0.1% to about 0.6% of a silicone gum when paired with a propellant concentration from 70% to 80% and a particulate concentration from 40% to 50%. In some instances, the antiperspirant composition may have from about 0.1% to about 0.4% of a silicone gum when paired with a propellant concentration from 70% to 80% and a particulate concentration from 50% to 60%. In some instances, the antiperspirant composition may have from about 0.3% to about 1.5% of a silicone gum when paired with a propellant concentration from 80% to 90% and a particulate concentration from 40% to 50%. In some instances, the antiperspirant composition may have from about 0.3% to about 1% of a silicone gum when paired with a propellant concentration from 80% to 90% and a particulate concentration from 50% to 60%. While it is believed to be very desirable to include a silicone gum in an antiperspirant composition comprising a non-volatile silicone fluid and at propellant concentrations from about 70% to about 90% or even about 95%, it is also contemplated that in some instances it may be desirable for the antiperspirant composition to be substantially or completely free of a silicone gum.
If a silicone gum is included, any silicone gum having a viscosity within the ranges described herein may be used, provided it is soluble in the liquid carrier, propellant or a combination thereof of the antiperspirant composition. Some suitable silicone gums include silicone polymers of the dimethyl polysiloxane type, which may have other groups attached, such as phenyl, vinyl, cyano, or acrylic, but the methyl groups should be in a major proportion. Silicone polymers having a viscosity below about 100,000 centistokes (molecular weight below about 100,000) at 25° C. are not considered silicone gums here but are rather, typically, considered a silicone fluid. One non-limiting example of silicone gum suitable for use is a silicone/gum fluid blend comprising a dimethiconol gum having a molecular weight form about 200,000 to 4,000,000 along with a silicone fluid carrier with a viscosity from about 0.65 to 100 mm2 s−1. An example of this silicone/gum blend is available from Dow Corning, Corp. of Michigan, USA under the trade name DC-1503 Fluid (88% dimethicone fluid/12% dimethiconol). Other silicone gums materials include SF1236 Dimethicone, SF1276 Dimethicone, and CF1251 Dimethicone available from Momentive Performance Materials, Inc. of NY, USA.
An antiperspirant composition is preferably substantially or completely free of water added as separate ingredient (i.e., anhydrous), as too much added water may result in several deleterious effects such as: 1) increasing the propensity for antiperspirant active particulates to agglomerate (thereby increasing the propensity for clogging), and 2) reducing dry feel on skin. It will be appreciated that even an anhydrous antiperspirant composition may still contain some water that is bound with an ingredient (e.g., antiperspirant active, tapioca material, etc.) otherwise added to the antiperspirant composition.
E. Particulate Materials
While the combination of high propellant concentration and a high concentration of non-volatile silicone fluids may provide a number of benefits, this combination may also involve a number of tradeoffs. For example, a high concentration of a non-volatile silicone fluid may result in a wet and/or sticky skin feel. In addition, a non-volatile silicone fluid may tend to impede release of the antiperspirant active more so than a volatile liquid carrier, as a volatile liquid carrier eventually evaporates leaving behind the antiperspirant active and the other non-volatile components, which are easily wetted by perspiration thereby releasing the antiperspirant active. In contrast, non-volatile silicones do not evaporate as easily and tend to be hydrophobic, thereby potentially decreasing antiperspirant active release.
Delivering a sufficient concentration of particulates to the skin is believed to improve the skin feel of an antiperspirant composition comprising a high concentration of a non-volatile silicone fluid. It is believed that an antiperspirant composition comprising a total non-volatile liquid material to total particulate material ratio (L/P ratio) from about 0.6, 0.8, 1, 1.2, or 1.4 to about 1.6, 1.4, 1.2 or 1 may balance the tradeoff between enough particulates to provide acceptable skin feel while minimizing the appearance of residue. An antiperspirant composition may have a total particulate concentration from about 30%, 35%, or 40% to about 50% or 45% by weight of the antiperspirant composition.
The antiperspirant composition may comprise a variety of particulate materials. However, it is believed that the type (e.g., hydrophilic v. hydrophobic) and concentrations of particulate materials included in an antiperspirant composition may, in some instances, impact skin feel, release of the antiperspirant active, and the propensity for clogging in the spray device. For example, too much antiperspirant active may result in a wet or sticky skin feel due to the propensity of antiperspirant actives to become sticky when hydrated (e.g., by perspiration) even within the L/P ratios previously described. In addition, too much of a hydrophobic particulate material may reduce release of the antiperspirant active from the composition. Conversely, inclusion of a hydrophilic particulate material may advantageously aid release of the antiperspirant active, which may be beneficial in a composition comprising a high concentration of a non-volatile silicone fluid. However, hydrophilic materials may increase the risk of clogging in the presence of water. Therefore, it may be desirable to balance these and other design considerations when incorporating particulate materials in an antiperspirant composition comprising a non-volatile silicone fluid.
Referring to Examples 9 to 14, various antiperspirant compositions comprising a non-volatile silicone fluid and having different total particulates, total liquids and liquid to particulate ratios were analyzed for the amount of visible residue provided by the antiperspirant composition. L/P ratios of 0.5, 0.8, 1, 1.4, 1.9 and 3.6 were tested. L/P ratios less than 1 are believed to provide very good feel characteristics (see, e.g., Example 3, wherein 44% solids and an L/P ratio of 1.27 provided minimal runniness). From Examples 9 to 14, it is believed that increasing L/P ratios tends to reduce the appearance of visible residue in an antiperspirant composition comprising a non-volatile silicone fluid and, further, that L/P ratios greater than about 1 may be particularly beneficial, as there appears to be a significant decrease in the appearance of residue at an L/P ratio of about 1 (e.g., comparing Examples 11 and 12) and thereafter. Therefore, it is believed that L/P ratios from about 1 to about 1.6 may be particularly beneficial in some instances for balancing the tradeoff between skin feel and residue in an antiperspirant composition comprising a non-volatile silicone fluid.
Some examples of particulate materials suitable for use include, but are not limited to, antiperspirant actives, powders (e.g., starch materials), encapsulated fragrance materials and bulking or suspending agents (e.g., silicas or clay materials). Other types of particulates may also be incorporated in an antiperspirant composition.
Antiperspirant Actives
An antiperspirant composition comprises one or more antiperspirant actives. The antiperspirant actives are in a particulate form (rather than being solubilized) in the antiperspirant composition. Therefore, it may be desirable that the antiperspirant composition is provided in a form other than an emulsion or is substantially or completely free of solubilizers for the antiperspirant active. The antiperspirant composition may be provided in the form of a liquid dispersion (including suspensions and colloids). This is in contrast to, for instance, WO 03/002082 which discloses solubilizing the antiperspirant active in an emulsion having a disperse phase and a continuous phase. Since the amount of antiperspirant active may significantly impact skin feel, an antiperspirant composition may comprise from about 16%, 18%, 20%, 22%, or 24% to about 34%, 32%, 30%, 28%, or 26% by weight of a particulate antiperspirant active. In some instances, it may be desirable to utilize a low concentration of the antiperspirant active, such as less than 20% or 18% by weight of the antiperspirant composition. The antiperspirant active concentrations refer to the anhydrous amount that is added. While the above-described ranges are believed to be most preferred for aesthetics, it is contemplated that in some instances it may be desirable for the concentration of the antiperspirant active particulates to be higher, such as, for example, up to 40% or more by weight of the antiperspirant composition.
Referring to Examples 15 to 22, various antiperspirant compositions were prepared with differing concentrations of antiperspirant active particulates, non-volatile silicone fluid, total particulate concentrations and antiperspirant active particulate concentration to total particulate concentration. It is believed that high concentrations of antiperspirant active particulates and/or high antiperspirant active concentration to total particulate concentration ratios (A/P) may result in antiperspirant compositions that are undesirably sticky and/or which may result in undesirable clumping or balling of the antiperspirant active particulates when wetted by a sweat event. A small amount of water was added to the antiperspirant compositions to simulate a sweat event and the amount of tack associated with antiperspirant composition post wetting was measured. Comparing Examples 15 and 16 (both of which had the same concentration of dimethicone but differing total solids), the tack associated with the antiperspirant composition of Example 16 increased significantly to a level believed to be too sticky. The antiperspirant composition of Example 16 had an A/P ratio of 0.9 and an antiperspirant active particulate concentration of 40%. Comparing Examples 17, 18 and 19, the antiperspirant compositions of Examples 17 and 19 had acceptable tack scores while the antiperspirant composition of Example 19 was believed to be too sticky. The antiperspirant composition of Example 19 had an A/P ratio of 0.94 and an antiperspirant active particulate concentration of 48%. Comparing Examples 20, 21 and 22, the antiperspirant composition of Example 20 was believed to be acceptable while the antiperspirant compositions of Examples 21 and 22 had some clumping when wetted. The antiperspirant composition of Example 22 had an A/P ratio of 0.86 and an antiperspirant active particulate concentration of 50%. It is believed that antiperspirant active particulate concentrations greater 35%, 40%, 45% or 50% may result in undesirable stickiness and/or clumping in use when the A/P ratio is greater than 0.8, 0.85, 0.9 or 0.95. Said another way, it may be desirable for the antiperspirant composition to have an A/P ratio less than about 0.95, 0.9, 0.85 or 0.8, or from about 0.1 or 0.3 to about 0.75, 0.7, 0.6 or 0.5.
The antiperspirant active may represent the highest concentration of particulate materials in the antiperspirant composition. For example, the antiperspirant active (on an anhydrous basis) may comprise from about 50% to about 80%, or from about 50% to about 70%, or from about 50% to about 60% of the total particulate materials in the antiperspirant composition. The balance of the total particulate concentration comprises non-antiperspirant active particulates. Some examples of suitable antiperspirant actives include astringent metallic salts, particularly including the inorganic and organic salts of aluminum. Some non-limiting examples exemplary aluminum salts that can be used include aluminum chloride and the aluminum hydroxyhalides having the general formula Al2(OH)aQbXH2O where Q is chloride, bromide, or iodide (preferably chloride), a is from about 2 to about 5, and a+b=about 6, and a and b do not need to be integers, and where X is from about I to about 6, and X does not need to be an integer. Particularly preferred are the aluminum chlorhydroxides referred to as “5/6 basic chlorhydroxide” wherein “a” is 5 and “2/3 basic chlorhydroxide” wherein “a” is 4. Aluminum salts of this type can be prepared in the manner described more fully in U.S. Pat. Nos. 3,887,692; 3,904,741; and 4,359,456. Preferred compounds include the 5/6 basic aluminum salts of the empirical formula Al2(OH)5DI2H2O; mixtures of AlCl36H2O and Al2(OH)5Cl2H2O with aluminum chloride to aluminum hydroxychloride weight ratios of up to about 0.5. Some examples of antiperspirant actives include, but are not limited to aluminum chlorohydrate, aluminum dichlorohydrate, aluminum sesquichlorohydrate, aluminum chlorohydrex propylene glycol complex, aluminum dichlorohydrex propylene glycol complex, aluminum sesquichlorohydrex propylene glycol complex, aluminum chlorohydrex polyethylene glycol complex, aluminum dichlorohydrex polyethylene glycol complex, aluminum sesquichlorohydrex polyethylene glycol complex, aluminum sulfate buffered, aluminum zirconium trichlorohydrate, aluminum zirconium tretrachlorohydrate, aluminum zirconium pentachlorohydrate, aluminum zirconium octachlorohydrate, aluminum zirconium trichlorohydrdrex glycine, aluminum zirconium tretrachlorohydrex glycine, aluminum zirconium pentachlorolaydrex glycine, aluminum zirconium octachlorohydrex glycine and combinations thereof. In some instances, the aluminum salt may be prepared by methods well known in the art. In some embodiments, the aluminum salts may be made by applying heat to a dilute aqueous solution of an aluminum salt (e.g., less than 20% of an aluminum salt by weight of the dilute solution) to form a solid aluminum salt comprising aluminum hydrolysis polymers. Some non-limiting examples of such methods are described in U.S. Pat. Nos. 4,871,525 and 4,359,456.
Substantially Inert Particulate Materials
The balance of the total particulate concentration of an antiperspirant composition may comprise excipient particulate materials that are substantially inert with respect to itself and/or antiperspirant active, meaning there are no significant particle to particle interactions with respect to itself and/or the antiperspirant active when present in the antiperspirant composition. Excipient particulate materials exclude clays and silicas added to an antiperspirant composition as bulking or suspending agents, as these particles can exhibit strong particle to particle interactions. The excipient particulate materials may be either hydrophilic or hydrophobic (including hydrophobically modified, which tend to be moderately hydrophobic). Some non-limiting examples of substantially inert excipient particulate materials that may be included in an antiperspirant composition include, but are not limited to, encapsulated fragrance materials; native starches such as tapioca, corn, oat, potato, and wheat starch particulates or hydrophibically modified versions of these starches; talc; calcium carbonate; perlite; mica and polyethylene beads. One non-limiting example of a hydrohobically modified corn starch material suitable for use comprises aluminum starch octenylsuccinate, which is available under the trade name Dry Flo PC or Dry Flo Pure from Akzo Nobel, Netherlands. The substantially inert particulates may be free flowing. An antiperspirant composition may comprise from about 0.25%, 0.5%, 1%, 5%, 10%, 12%, or 14% to about 25%, 22%, 20%, 18%, or 16% by weight of the antiperspirant composition of substantially inert particulates. One substantially inert particulate material believed to be suitable for use is a hydrophilic or hydrophobically modified tapioca starch material. A tapioca starch material may be particularly beneficial as it is unlikely to induce an allergic reaction if inhaled. Tapioca is a starch which may be extracted from the cassava plant, typically from the root, which may then be processed or modified as known in the art. Tapioca starches are, advantageously, substantially non-allergenic. One non-limiting example of a hydrophobically modified tapioca starch material suitable for use comprises a silicone grafted tapioca starch, which is available under the trade name Dry Flo TS from AkzoNobel of the Netherlands. The INCI name is tapioca starch polymethylsilsesquioxane and may be produced by a reaction of methyl sodium siliconate (polymethylsilsesquioxane) and tapioca starch. This silicone grafted tapioca starch material is commercially available as CAS No. 68989-12-8. The silicone grafted tapioca starch material can be formed using any known means, including, but not limited to those methods described in U.S. Pat. Nos. 7,375,214, 7,799,909, 6,037,466, 2,852,404, 5,672,699, and 5,776,476. Other non-limiting examples of hydrophobically modified tapioca starch materials that are suitable for use include Dry Flo AF (silicone modified starch from Akzo Nobel), Rheoplus PC 541 (Siam Modified Starch), Acistar RT starch (available from Cargill) and Lorenz 325, Lorenz 326, and Lorenz 810 (available from Lorenz of Brazil). In some specific embodiments, the tapioca starch material may be hydrophilic in order to facilitate release of the antiperspirant active during use. One non-limiting example of a hydrophilic tapioca starch material suitable for use is available under the trade name Tapioca Pure available from Akzo Nobel. In some specific embodiments, the substantially inert particulate material comprises a hydrophilic tapioca material, a hydrophobic tapioca material or a mixture thereof.
An antiperspirant composition may optionally comprise one or more particulate fragrance carriers or materials that may or may not encapsulate a perfume component. Fragrance carriers are typically particulates, which would be considered part of the total particulate concentration of the antiperspirant composition. The fragrance carriers are preferably hydrophobic in order to minimize particle-to-particle interactions. The fragrance carriers may be either full or empty. A full fragrance carrier is a fragrance carrier that encapsulates or otherwise contains a perfume component while the fragrance carrier is stored within the spray device. Full fragrance carriers may release their perfume components by a variety of mechanisms post delivery from the spray device to provide a desired aroma or fragrance experience for a user. For example, the perfume components may be released by moisture upon wetting of the fragrance carrier, e.g., by perspiration or other body fluids. Alternatively or in addition thereto, the perfume components may be released by fracture of the carrier, such as by the application of pressure or a shearing force. An empty fragrance carrier is a fragrance carrier that does not contain a perfume component while stored within the spray device. One non-limiting example of an empty fragrance carrier is an uncomplexed cyclodextrin material.
Some non-limiting examples of fragrance carriers suitable for encapsulating a perfume component include, but are not limited to, oligosaccharides (e.g., cyclodextrins), starches, polyethylenes, polayamides, polystyrenes, polyisoprenes, polycarbonates, polyesters, polyacrylates, vinyl polymers, silicas, and aluminosilicates. Some examples of fragrance carriers are described in USPNs 2010/0104611; 2010/0104613; 2010/0104612; 2011/0269658; 2011/0269657; 2011/0268802; U.S. Pat. No. 5,861,144; U.S. Pat. No. 5,711,941; U.S. Pat. No. 8,147,808; and U.S. Pat. No. 5,861,144.
An antiperspirant composition may comprise from about 0.25%, 0.5%, 0.75%, 1%, or 2% to about 20%, 16%, 12%, 10%, 8%, 6% or 4% by weight of the antiperspirant composition of fragrance carriers. In some instances, the substantially inert excipient particles of the antiperspirant composition consist essentially of or completely of full fragrance carriers, empty fragrance carriers, or mixtures thereof. An antiperspirant composition may comprise from about 0.25%, 0.5%, 0.75%, or 1% to about 6%, 4% or 2% by weight of the antiperspirant composition of full fragrance carriers. An antiperspirant composition may comprise from about 0.25%, 0.5%, 1%, or 2% to about 16%, 12%, 10%, 8%, 6% or 4% by weight of the antiperspirant composition of empty fragrance carriers. In some instances, it may be desirable to incorporate a mixture of empty fragrance carriers and full fragrance carriers in the antiperspirant composition, wherein the empty fragrance carriers may be included to achieve the desired overall particulate concentration without the risk of perfume over-dosing.
In some instances, it may be desirable to provide a mixture of fragrance carriers and native starch powders to achieve the desired particle concentration. For example, from about a 20:80 to 80:20 (fragrance carrier to starch) mixture might be utilized. In some instances, a 50:50 mixture might be utilized and in other instances the native starch powders might have a concentration equal to about or less than 6% by weight of the antiperspirant composition while the concentration of the fragrance carriers might be equal to about or less than 9% by weight of the antiperspirant composition.
A wide variety of perfume components may be used with the fragrance carriers, including but not limited to volatile perfume components having a boiling point at normal pressure of less than about 260° C., more preferably less than about 250° C., and perfume components having significant low odor detection threshold, and mixtures thereof. The boiling points of many perfume components are given in, e.g., “Perfume and Flavor Chemicals (Aroma Chemicals),” Steffen Arctander, published by the author, 1969.
Bulking and Suspending Agents
An antiperspirant composition may comprise a bulking or suspending agent. In some instances, it may be desirable to include a bulking or suspending agent in the antiperspirant composition in order to reduce the risk of caking of the antiperspirant composition at the bottom of the container and/or to aid in the redispersion of the antiperspirant composition upon shaking without significant clumping so as to reduce the risk of clogging any small orifices within the spray device. This may be particularly useful as antiperspirant actives are dense and tend to settle quickly and/or may be prone to caking in the presence of moisture. Significant settling and/or agglomeration of particulates in an antiperspirant composition may complicate delivery of a uniform dose of the antiperspirant active from a spray device. This in turn may negatively impact skin feel or contribute to the appearance of a white residue. While other solutions for addressing redispersion, settling and/or caking may be employed, there may also be tradeoffs involved. For example, U.S. Pat. No. 7,815,899 suggests utilizing a high viscosity polymeric material (e.g., a quartenary ammonium functional silicone) to reduce the settling rate. However, this approach may, in some instances, have tradeoffs. For example, some quaternary silicones have a strong odor from amine impurities that can interfere with fragrance of the product. Moreover, these amines may negatively interact with the active via a lewis acid/base reaction.
The bulking or suspending agent may be hydrophobic, hydrophilic or comprise mixtures thereof. In some specific embodiments, these materials may be hydrophilic in order to facilitate release of the antiperspirant active during use. Some examples of silica materials that may be used include, but are not limited to, colloidal silicas. Some non-limiting examples of silica materials are available from Evonik Industries under the trade names Aerosil 200SP, Aerosil 300SP and Aerosil R972.
In some instances, the antiperspirant composition may include a clay material. Some non-limiting examples of clay materials include montmorillonite clays and hydrophobically treated montmorillonite clays. Montmorillonite clays are those which contain the mineral montmorillonite and may be characterized by a having a suspending lattice. Some examples of these clays include but are not limited to bentonites, hectorites, and colloidal magnesium aluminum silicates. Some non-limiting examples of organoclays include modified bentonite, modified hectorite, modified montorlinite and combinations thereof, some examples of which are available under the trade names Bentone 27 (stearalkonium bentonite), Bentone 34 (stearalkonium bentonite) and Bentone 38 (disteardimonium hectorite) from Elementis Specialities Plc. and Tixogel VPV (quaternium 90-bentonite), Tixogel VZV (stearalkonium bentonite), Tixogel LGM (stearalkonium bentonite) and Claytone SO (stearalkonium bentonite) from Southern Clay Products.
The antiperspirant composition may also comprise a clay activator, such as propylene carbonate, triethyl citrate, methanol, ethanol, acetone, water and mixtures and derivatives thereof. Clay activators may also strongly interact with an antiperspirant active (e.g., leading to clumping or coating of the antiperspirant active and/or changes in active polymer structure which may reduce antiperspirant efficacy). Therefore, it may be desirable to limit the amount of clay activator present in the antiperspirant composition to between about 0.5%, 0.75%, 1%, 1.25%, or 1.5% to about 3%, 2%, or 1.75% by weight of the antiperspirant composition.
III. SPRAY DEVICES
In order to avoid over-dosing of the antiperspirant composition, it is desirable that the spray device have a total mass flow rate of the propellant/antiperspirant composition mixture of less than 1.25 grams/sec or from about 0.5 grams/sec to about 1.3 grams/sec, or from about 0.6 grams/sec to about 1.0 grams/sec, or from about 0.7 grams/sec to about 1.0 grams/sec. The spray device may have an antiperspirant composition mass flow rate less than 0.3 grams/sec or from about 0.1 grams/sec to about 0.3 grams/sec or from about 0.1 grams/sec to 0.2 grams/sec or from about 0.15 grams/sec to about 0.2 grams/sec. It is believed that mass flow rates greater than described above may lead to a wet or sticky skin feel (even if the L/P ratio is within the ranges previously described), because the total amount of antiperspirant composition deposited on the skin may be too great.
The amount of antiperspirant active delivered to a target surface by a two second application from a spray device may be from about 40 mg, 50 mg, 60 mg, or 70 mg to about 100 mg, 90 mg, or 80 mg. The total amount of antiperspirant composition delivered to a target surface by a two second application of a spray device may be from about 0.1 grams to about 0.4 grams, or from about 0.2 grams to about 0.4 grams, or from about 0.2 grams to about 0.3 grams. The amount of liquid fragrance material delivered to a target surface by a two second application of a spray device may be from about 3 mg to about 20 mg, or from about 6 mg to about 15 mg, or from about 6 mg to about 12 mg. The amount of full fragrance carriers delivered to a target surface by a two second application of a spray device may be from about 0.75 mg to about 15 mg, or from about 1 mg to about 12 mg, or from about 1 mg to about 9 mg. The spray device may have a deposition efficiency, of either the antiperspirant composition and/or the antiperspirant active and/or the liquid fragrance material, that is from about 50%, 55%, 60%, 70% or 75% to about 85%, 80%, or 75%.
Referring to FIG. 2, one non-limiting example of a spray device that may be used with the antiperspirant compositions and propellants described herein is shown. While the spray device of FIG. 2 is described hereafter as one spray device suitable for use, it will be appreciated that many other spray devices, including other types of actuators and valve assemblies, etc., may also be used with the antiperspirant compositions and propellants described herein. The spray device 100 comprises a container 102, a liquid propellant 104 and an antiperspirant composition 106. It will be appreciated that the propellant 104 and antiperspirant composition 106 are merely shown for purposes of illustration in FIG. 2, and FIG. 2 is not intended to limit in any way the type or arrangement of the propellant and antiperspirant composition within the container 102. For example, in some instances the propellant and the composition are miscible such that distinct layers may not be visible. The spray device 100 may be shaped and configured so that it is hand-holdable. The container 102 comprises a body 108, an actuator 110 having an actuator orifice 112, and a valve assembly 114 in fluid communication with a reservoir 118 storing the composition 106 and liquid propellant 104. The reservoir 118 may be defined by one or more interior surfaces of the body 108. The reservoir may have a volume from about 20 ml, 40 ml, or 60 ml to about 120 ml, 110 ml, 100 ml, or 90 ml. A dip tube 119 may extend into the reservoir 118 from the valve assembly. A gaseous propellant 120 may fill the headspace of the reservoir 118. The valve assembly 114 comprises a slidably disposed valve stem 124 to which the actuator 110 attaches, a mounting flange 128 for attaching the valve assembly 114 to the body 108 (such as by crimping), and a housing 130 attached to the mounting flange 128. A valve is provided within the valve assembly, which may take the form of a substantially flat elastomeric seal disposed about the valve stem 124 which seals one or more horizontally disposed holes in the valve stem 124, thereby preventing the antiperspirant composition from flowing from the dip tube thru the valve stem 124 to the actuator 110. Conversely, depressing the actuator 110 breaks the seal thereby permitting the antiperspirant composition and propellant mixture to flow through the valve stem to the actuator 110 and out of the actuator orifice 112. The housing 130 may be attached by a variety of means to the mounting flange, as known in the art, including by a press fit, positive latching, welding, etc. The housing 130 contains a spring 132 that biases the valve stem 124. The spring 132 may comprise a plurality of coils. One example of a non-limiting valve assembly suitable for use is described in U.S. Pat. No. 4,396,152. One example of a valve assembly having the general configuration shown in FIG. 5 is available from the Precision Valve Company (USA) under the trade name Ecosol.
A user of a spray device may initiate a spray by depressing an actuator, thereby opening a valve which enables a liquid propellant/antiperspirant composition mixture to exit the actuator. Prior to actuation, it may be desirable to shake or rotate the product to redisperse the liquid and particulate materials. While usage time can vary widely, users may depress the actuator from about 2 seconds to about 5 seconds, or from about 2 seconds to about 4 seconds, or from about 2 seconds to about 3 seconds to provide a burst of antiperspirant composition for deposition to an underarm or axillia skin surface. A spray device may be sized to provide a total spray time from about 60 seconds to about 200 seconds, or from about 70 seconds to about 150 seconds, for from about 90 seconds to about 130 seconds, thereby providing from about 15 to about 50 two second uses before exhaustion.
IV. MEASUREMENT METHODS
Propellant Concentration and Antiperspirant Composition Concentration
The overcap (if one is present) of the product container is removed, and the weight of the container and its contents (gross mass) is measured using any suitable scale, such as an analytical balance. The top of the container is punctured using any suitable tool, such as an AC-PD Aerosol Can Puncturing Device available from Aero-Tech Laboratory Equipment Company, LLC of Missouri, USA. The puncture needle is fully extended into the container, and the puncture needle is slowly retracted to permit the gaseous propellant to evacuate the container. Once the puncture needle is completely retracted from the container, the puncturing device can be removed from the container, and the propellant will continue to escape from the puncture in the container. All the propellant is allowed to evacuate from the container.
The mass of the container and the remaining contents (less the propellant) is measured using any suitable device, such as an analytical balance. The actuator is removed from the container using any suitable device, such as an Aero-Tech Can Decrimper available from Aero-Tech Laboratory Equipment Company, LLC of Missouri, USA. The inside of the container is rinsed with ethanol until visually clean and the container is allowed to dry for at least 2 hours. The mass of the empty container and actuator is measured using any suitable device, such as an analytical balance. The propellant mass and concentration may be determined using the following equations:



  
    
      Propellant
      ⁢
      
        
      
      ⁢
      Mass
      ⁢
      
        
      
      ⁢
      
        (
        g
        )
      
    
    =
    
      
        Gross
        ⁢
        
          
        
        ⁢
        Mass
      
      -
      
        Mass
        ⁢
        
          
        
        ⁢
        After
        ⁢
        
          
        
        ⁢
        Propellant
        ⁢
        
          
        
        ⁢
        Evacuation
      
    
  




  
    
      Propellant
      ⁢
      
        
      
      ⁢
      Concentration
      ⁢
      
        
      
      ⁢
      %
    
    =
    
      
        Propellant
        ⁢
        
          
        
        ⁢
        Mass
      
      
        
          Gross
          ⁢
          
            
          
          ⁢
          Mass
        
        -
        
          Mass
          ⁢
          
            
          
          ⁢
          of
          ⁢
          
            
          
          ⁢
          Empty
          ⁢
          
            
          
          ⁢
          Container
        
      
    
  



Antiperspirant composition concentration may be derived from the following equation:

Antiperspirant Composition Concentration %=100−Propellant Concentration %

Antiperspirant Composition Deposition Efficiency, Amount Dispensed, and Amount Deposited
At least four aerosol antiperspirant product samples are tested. The product samples are shaken if directed and the actuator is actuated for 2 to 3 seconds, after which each product sample is weighed to measure its mass using any suitable device, such as an analytical balance. The product samples are then immersed in a constant-temperature (25° C.) bath until the internal pressure stabilizes at a temperature of 25° C. At least twelve filter papers, such as Whatman 150 mm (diameter) Filter Paper available under the catalog number 1003-150 from the Whatman Company of the UK, are weighed to measure the mass of the filter using any suitable device, such as an analytical balance. The product samples are removed from the bath, and any excess moisture is removed by blotting with a paper towel. The product samples are shaken if directed, and the product sample is positioned approximately 15 cm away from one of the filter papers, which is preferably weighted and/or fixtured to assure the filter paper does not move during spraying. The actuator of the product sample is actuated for 5 seconds which may be accurately timed using a stopwatch. It will be appreciated, however, that other spray times may be substituted. For example, a two second spray time period might be used to better approximate the amount dispensed/deposited during a typical use cycle by a consumer. The spray from the product sample should be centered on the center of the filter paper. After spraying, the filter paper and product sample are weighed to measure the mass using any suitable device, such as an analytical balance. The steps of bathing, weighing, and actuating are repeated three times for each of the product samples. The average antiperspirant composition efficiency may be calculated using the following equations, averaged across the four product samples and the three repetitions per product sample:



  
    
      Amount
      ⁢
      
        
      
      ⁢
      Dispensed
      ⁢
      
        
      
      ⁢
      
        (
        g
        )
      
    
    =
    
      
        Product
        ⁢
        
          
        
        ⁢
        Sample
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        Before
        ⁢
        
          
        
        ⁢
        Spraying
      
      -
      
        Product
        ⁢
        
          
        
        ⁢
        Sample
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        After
        ⁢
        
          
        
        ⁢
        Spraying
      
    
  




  
    
      Amount
      ⁢
      
        
      
      ⁢
      Deposited
      ⁢
      
        
      
      ⁢
      
        (
        g
        )
      
    
    =
    
      
        Filter
        ⁢
        
          
        
        ⁢
        Paper
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        After
        ⁢
        
          
        
        ⁢
        Spraying
      
      -
      
        Filter
        ⁢
        
          
        
        ⁢
        Paper
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        Before
        ⁢
        
          
        
        ⁢
        Spraying
      
    
  




  
    
      Antiperspirant
      ⁢
      
        
      
      ⁢
      Composition
      ⁢
      
        
      
      ⁢
      Deposition
      ⁢
      
        
      
      ⁢
      
        Efficiency
        ⁡
        
          (
          %
          )
        
      
    
    =
    
      100
      ×
      
        
          Amount
          ⁢
          
            
          
          ⁢
          Deposited
        
        
          Amount
          ⁢
          
            
          
          ⁢
          Dispensed
          *
          Antiperspirant
          ⁢
          
            
          
          ⁢
          Composition
          ⁢
          
            
          
          ⁢
          Weight
          ⁢
          
            
          
          ⁢
          %
        
      
    
  



Antiperspirant Active Deposition Efficiency, Amount Dispensed, and Amount Deposited
At least four aerosol antiperspirant product samples are tested. The product samples are shaken if directed and the actuator is actuated for 2 to 3 seconds, after which each product sample is weighed to measure its mass using any suitable device, such as an analytical balance. The product samples are then immersed in a constant-temperature (25° C.) bath until the internal pressure stabilizes at a temperature of 25° C. The product samples are then removed from the bath and excess moisture is removed by blotting with a paper towel. At least twelve filter papers, such as Whatman 150 mm Filter Paper available under the catalog number 1003-150 from the Whatman Company of the UK, are weighed to measure the mass of the filter using any suitable devices, such as an analytical balance. The product samples are removed from the bath, and any excess moisture is removed by blotting with a paper towel. The product samples are shaken if directed, and the product sample is positioned approximately 15 cm away from one of the filter papers, which is preferably weighted and/or fixtured to assure the filter paper does not move during spraying. The actuator of the product sample is actuated for 5 seconds which may be accurately timed using a stopwatch. It will be appreciated that other spray times may be substituted. For example, a two second spray time period might be used to better approximate the amount dispensed/deposited during a typical use cycle by a consumer. The spray from the product sample should be centered on the center of the filter paper. After spraying, the filter paper and product sample are weighed to measure the mass using any suitable device, such as an analytical balance. The steps of bathing, weighing, and actuating are repeated three times for each of the product samples. The amount of antiperspirant active deposited on a filter paper may be determined using an automated titrator, such as MettlerDL-70 equipped with Mettler DM141C combination silver-silver chloride electrode available from Mettler, Inc. Alternatively, the amount of antiperspirant active deposited on a filter paper may be determined using the Content of Chloride Method set forth in the USP monograph for aluminum chlorohydrate (USP 35) or an equivalent method. The average antiperspirant active deposition efficiency may be calculated using the following equations, averaged across the four product samples and the three repetitions per product sample:



  
    
      Amount
      ⁢
      
        
      
      ⁢
      Dispensed
      ⁢
      
        
      
      ⁢
      
        (
        g
        )
      
    
    =
    
      
        Product
        ⁢
        
          
        
        ⁢
        Sample
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        Before
        ⁢
        
          
        
        ⁢
        Spraying
      
      -
      
        Product
        ⁢
        
          
        
        ⁢
        Sample
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        After
        ⁢
        
          
        
        ⁢
        Spraying
      
    
  




  
    
      Amount
      ⁢
      
        
      
      ⁢
      Deposited
      ⁢
      
        
      
      ⁢
      
        (
        gm
        )
      
    
    =
    
      
        Filter
        ⁢
        
          
        
        ⁢
        Paper
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        Before
        ⁢
        
          
        
        ⁢
        Spraying
      
      -
      
        Filter
        ⁢
        
          
        
        ⁢
        Paper
        ⁢
        
          
        
        ⁢
        Weight
        ⁢
        
          
        
        ⁢
        After
        ⁢
        
          
        
        ⁢
        Spraying
      
    
  




  
    
      Antiperspirant
      ⁢
      
        
      
      ⁢
      Composition
      ⁢
      
        
      
      ⁢
      
        Efficiency
        ⁡
        
          (
          %
          )
        
      
    
    =
    
      100
      ×
      
        
          Amount
          ⁢
          
            
          
          ⁢
          Deposited
        
        
          Amount
          ⁢
          
            
          
          ⁢
          Dispensed
          *
          Antiperspirant
          ⁢
          
            
          
          ⁢
          Composition
          ⁢
          
            
          
          ⁢
          Weight
          ⁢
          
            
          
          ⁢
          %
        
      
    
  



V. EXAMPLES
The following examples are given solely for the purpose of illustration and are not to be construed as limitations of the invention as many variations thereof are possible without departing from the spirit and the scope of the invention.
Examples 1, 2 and 3
Examples 1, 2 and 3 illustrate the effect that total particulate concentration may have on viscosity and the effect that viscosity may have on “runniness”.













Ingredient
Example 1
Example 2
Example 3







Aluminum chlorohydrate1
26% 
26% 
26% 


Dimethicone 50 centistokes
63.54%   
56.54%   
49.54%   


Hydrophilic tapioca2
0%
5%
12% 


Disodium Hectorite3
3%
3%
3%


Triethyl citrate
0.96%  
0.96%  
0.96%  


Liquid Perfume
5.5%  
5.5%  
5.5%  


Betacyclodextrin fragrance
1%
3%
3%


Average Viscosity (centistokes)
950
2050
5500


Total Particulate Concentration
30% 
37% 
44% 


L/P Ratio
   2.3
  1.7
    1.27





The values are shown on a by weight of the antiperspirant composition basis.


186% assay of anhydrous active, average particle size approximately 15 microns.


2Tapioca Pure available from Akzo Nobel


3Bentone 38 available from Elementis






The antiperspirarant compositions of Examples 1 to 3 are made using the following general batch method: a first portion of the dimethicone is added to an appropriately sized container followed by the clay and the mixture was milled for at least 2 minutes at a speed of 10,000 to 12,000 rpm using a hand held mill. Triethyl citrate is then added to the mixture and milled for at least 2 minutes. The balance of dimethicone is added to the mixture and milled for at least 2 minutes. The antiperspirant active, tapioca starch, betacyclodextrin fragrance and liquid perfume are added to the mixture and milled for at least 2 minutes.
Approximately 0.1 ml of the antiperspirant compositions of Examples 1, 2 and 3 are deposited, using a syringe, on horizontally positioned skin mimic samples attached to a black paperboard backsheet. A description of the skin mimic material may be found in U.S. Pat. No. 8,124,064 (col. 8, lines 30 to 47). The paperboard backsheet is then rotated to a vertical position for approximately 10 seconds. The drip length is then measured. This process is repeated three times. FIG. 13 is a photograph of one set of three antiperspirant compositions on the skin mimic material after about 10 seconds in the vertical position. The antiperspirant compositions of Example 1 have an average drip length of 40 mm (range=38 mm to 42 mm). The antiperspirant compositions of Example 2 have an average drip length of 20.6 mm (range=20 mm to 22 mm), and the antiperspirant compositions of Example 3 have an average drip length of 11 mm (range=10 mm to 12 mm).
Examples 4 to 8
Examples 4 to 8 illustrate the effect that silicone gum concentration may have on spray pattern.
















Ex 4
Ex 5
Ex 6
Ex 7
Ex 8




















Dimethicone 50 Cst
49.8%
47.8%
44.8%
41.8%
38.8%


Alumininum Chlorohydrate 1
28.0%
28.0%
28.0%
28.0%
28.0%


Hydrophilic tapioca2
12.0%
12.0%
12.0%
12.0%
12.0%


Liquid Fragrance
 3.5%
 3.5%
 3.5%
 3.5%
 3.5%


Betacyclodextrin fragrance
 3.0%
 3.0%
 3.0%
 3.0%
 3.0%


Disteardimonium Hectorite3
 2.0%
 2.0%
 2.0%
 2.0%
 2.0%


Silicone gum material4
 1.0%
 3.0%
 6.0%
 9.0%
12.0%


Triethyl citrate
 0.7%
 0.7%
 0.7%
 0.7%
 0.7%





The values are shown on a by weight of the antiperspirant composition basis


1 86% assay of anhydrous active, average particle size approximately 15 microns.


2Dri Flo TS available from Akzo Nobel


3Bentone 38 available from Elementis


4DC1503 (a mixture of dimethicone and dimethiconol) available from Dow Corning. DC1503 comprises approximately 12% by weight of the mixture of a silicone gum (dimethiconol).






The antiperspirarant compositions of Examples 4 to 8 are made using the following general batch method: a first portion of the dimethicone is added to an appropriately sized container followed by the clay and the mixture is milled for at least 2 minutes at a speed of 10,000 to 12,000 rpm using a hand held mill. Triethyl citrate is then added to the mixture and milled for at least 2 minutes. The balance of dimethicone and the silicone gum material are added to the mixture and milled for at least 2 minutes. The antiperspirant active, tapioca starch, betacyclodextrin fragrance and liquid perfume are added to the mixture and milled for at least 2 minutes. The antiperspirant compositions are added to the product container together with A-46 propellant to achieve a 85% propellant concentration by weight of the total fill of materials. The antiperspirant composition is sprayed onto a black paperboard from a distance of approximately 15.2 cm (6 inches) for approximately 2 seconds. The diameter of the spray pattern and the deposition characteristics are set forth below.














Spray 





Diameter
% 




(cm)
Deposition
Observations


















Example 4
7.2
57
Gassy spray, even pattern


Example 5
6.6
63
Even pattern


Example 6
6.3
70
Even pattern


Example 7
5.8
75
Majority of composition within





2 cm of center with a noticeable





mound in the center.


Example 8
5.5
77
Majority of composition within





2 cm of center with a large





mound in the center.









Examples 9 to 14
Examples 9 to 14 illustrate the effect that increasing L/P ratio may have on residue for an antiperspirant composition comprising a non-volatile silicone fluid.
















Ingredient
Ex 9
Ex 10
Ex 11
Ex 12
Ex 13
Ex 14







Aluminum chlorohydrate1
30%
30%
30%
25%
30% 
20% 


Dimethicone - 50
30.8% 
40.8% 
45.8% 
53.8% 
60.8%  
73.8%  


centistoke


Betacyclodextrin
 3%
 3%
 3%
 0%
3%
0%


fragrance


Uncomplexed
30%
20%
15%
15%
0%
0%


Betacyclodextrin


Disodium Hectorite
 2%
 2%
 2%
 2%
2%
2%


Triethyl Citrate
 1%
 1%
 1%
 1%
1%
1%


Perfume
3.5% 
3.5% 
3.5% 
3.5% 
3.5% 
3.5% 


Total Particulates
65%
55%
50%
42%
35% 
22% 


L/S ratio
0.5
0.8
1
1.4
1.9
3.6


Approximate Residue/g
327   
238   
175 
42  
25  
0.9









The antiperspirant compositions are combined with A-46 propellant in a spray device at a ratio of 80% propellant to 20% antiperspirant composition. The antiperspirant spray devices are shaken and then the antiperspirant composition is sprayed on a black, artificial leather material (Naugahyde available from Uniroyal Engineered Products LLC) from a distance of about 15 cm (6 inches). The target surface has a size of about 15 cm×10 cm. The spray time is about 4 seconds and the target surface is coated as evenly as possible. The amount of antiperspirant composition deposited on the naugahyde material is determined by weighing the material before and after application of the antiperspirant composition. The L value (L* in the L*A*B* color space) of the antiperspirant composition on the treated naugahyde material is measured at three different locations on the surface using a colorimeter (e.g., Model CR-400 available from Konica-Minolta, Japan). The L values of an untreated naugandye surface are also measured at three locations using the colorimeter. The whiteness of the antiperspirant composition (e.g., observable residue) is approximated by subtracting the average L value derived from three colorimeter measurements of the untreated naugahyde surface from the average L value derived from the three colorimeter measurements of the treated naugahyde surface divided by the amount antiperspirant composition deposited.

Examples 15 to 22
Examples 15 to 22 illustrate the effect that antiperspirant active particulate concentration and/or A/P ratio may have on antiperspirant composition tack following wetting.


















Ingredient
Ex 15
Ex 16
Ex 17
Ex 18
Ex 19
Ex 20
Ex 21
Ex 22







Aluminum chlorohydrate1
26%
40% 
26%
40% 
48% 
26%
40%
50% 


Dimethicone - 50
48.04%  
48.04%   
32.04%  
32.04%   
32.04%   
35.04%  
35.04%  
35.04%   


centistoke


Hydrophilic tapioca2
12%
0%
19%
5%
0%
26%
12%
2%


Disodium Hectorite3
 3%
3%
 3%
3%
3%
 3%
 3%
3%


Triethyl citrate
0.96% 
0.96%  
0.96% 
0.96%  
0.96%  
0.96% 
0.96% 
0.96%  


Betacyclodextrin
 3%
1%
 3%
3%
3%
 3%
 3%
3%


fragrance


Silicone gum4
0.5% 
0.5% 
0.5% 
0.5% 
0.5% 
0.5% 
0.5% 
0.5% 


A/P ratio
0.59
0.9
0.51
0.78
0.94
0.44
0.69
0.86


Total Particulates
44%
44% 
51%
51% 
51% 
58%
58%
58% 


Average gF
226   
342   
159   
216   
253   
179   
282   
182   





The values are shown on a by weight of the antiperspirant composition basis.


186% assay of anhydrous active, average particle size approximately 15 microns.


2Tapioca Pure available from Akzo Nobel


3Bentone 38 available from Elementis


4DC1503 (a mixture of dimethicone and dimethiconol) available from Dow Corning. DC1503 comprises approximately 12% by weight of the mixture of a silicone gum (dimethiconol).






Examples 15 to 22 are made using the following general batch method: a first portion of the dimethicone is added to an appropriately sized container followed by the clay and the mixture is milled for at least 2 minutes at a speed of 10,000 to 12,000 rpm using a hand held mill. Triethyl citrate is then added to the mixture and milled for at least 2 minutes. The balance of dimethicone and the silicone gum material are added to the mixture and milled for at least 2 minutes. The antiperspirant active, tapioca starch, betacyclodextrin fragrance and liquid perfume are added to the mixture and milled for at least 2 minutes.
Approximately 0.3 to 0.305 grams of each antiperspirant composition is added to a 6 dram vial after which about 65 microliter of water was added. The vial is sealed and a vortex mixer was used for 1 minute to mix the materials. After mixing, the antiperspirant composition is subjected to the following method to measure its tack or stickiness. The method measures the force (gF) required to separate two surfaces having an antiperspirant composition disposed between them. Lower gram force (gF) measurements being indicative of less stickiness and liquidity (wetness). Measurements are performed using a TA XT plus texture analyzer, such as available from Stable Micro Systems (Surrey England), that utilized a cylinder probe. 25 mm diameter pieces of Leneta card are affixed to both the cylinder probe and base of the actuator. 0.03 to 0.0305 gram of an antiperspirant composition sample is placed between the lineta cards and the instrument is then set to compress the cards together with a 200 gF for 2 seconds and then separated at a speed of 10 mm/sec. The amount of force required to separate the cards is measured as the two are separated. This is repeated 30 times with the first 5 repititions being averaged to determine a gF for the composition. The average gF values for each antiperspirant composition, along with the concentration of total particulates and the A/P ratio for the antiperspirant composition, are set forth in the table above. The antiperspirant composition of Example 22 contained clumping within the composition as did Example 21 (although less so than observed in Example 22), which is believed to have affected these gF values.
Examples 23, 24 and 25
Examples 23, 24 and 25 further describe and demonstrate some non-limiting examples of antiperspirant compositions made in accordance with the invention.













Ingredient
Example 23
Example 24
Example 25







Aluminum chlorohydrate1
28% 
28% 
19% 


Dimethicone
48.38%   
52.3%  
61.25%   


Cyclopentasiloxane2
0%
0%
0%


Hydrophobic tapicoa3
12% 
0%
0%


Hydrophilic tapioca4
0%
12% 
12% 


Disodium Hectorite5
2%
0%
0%


Triethyl citrate
0.67%  
0%
0%


Silicone gum material6
1%
0%
0%


Hydrophilic silica7
0%
1%
1%


Hydrophobic silica8
0%
0.25%  
0.25%  


Liquid Perfume
3.5%  
3.5%  
3.5%  


Betacyclodextrin fragrance
3%
3%
3%





The values are shown on a by weight of the antiperspirant composition basis.


186% assay of anhydrous active, average particle size approximately 15 microns.


2DC 200 Fluid (50 cst) available from Dow Corning


3Dry Flo TS from Akzo Nobel


4Tapioca Pure from Akzo Nobel


5Bentone 38 available from Elementis


6DC1503 (a mixture of dimethicone and dimethiconol) available from Dow Corning


7Aerosil A300 silica from Evonik


8Aerosil A300 silica from Evonik






The antiperspirarant compositions of Examples 23 to 25 are made using the following general batch method: the non-volatile silicone fluid is added to an appropriately sized container followed by the silica (or clay in the case of Example 23) and the mixture is milled for at least 1 minute at a speed of 10,000 to 12,000 rpm using a hand held mill. In the case of Example 23, triethyl citrate is then added to the mixture and milled for at least 5 minutes. The antiperspirant active particles are added to the mixture and milled for at least 1 minute (Examples 24, 25) or at least 5 minutes (Example 23). The tapioca starch material and betacyclodextrin fragrance are added to the mixture and milled for at least one minute (Examples 24 and 25) or at least 5 minutes (Example 24). The perfume is then added (and in the case of Example 23, the silicone gum) and milled for at least one minute.
Antiperspirant compositions of Example 23 have an average viscosity of approximately 1,500 centipose, and antiperspirant compositions of Example 24 have an average viscosity of approximately 4,200 centipose. Antiperspirant compositions of Example 25 have an average viscosity of approximately 3,000 centipose. The viscosity measurements are made using a Brookfield Viscometer Model 1/2RVT using an RV-4 spindle using techniques well known in the art.
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.” All numeric values (e.g., dimensions, flow rates, pressures, concentrations, etc.) recited herein are modified by the term “about”, even if not expressly so stated with the numeric value.
Every document cited herein, including any cross referenced or related patent or application is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.

## Claims

1. An aerosol antiperspirant composition, comprising:
a propellant having a concentration from 70% to 95%, by weight of the aerosol antiperspirant composition;
an antiperspirant composition comprising:
one or more liquid materials comprising 70% to 100% by weight of the liquid materials, of non-volatile polydimethyl siloxane fluid; the one or more liquid materials having a concentration from 40% to about 70% by weight of the antiperspirant composition;
an antiperspirant active particulate;
one or more non-antiperspirant active particulates that are substantially inert, selected from the group consisting of native starches, particulate fragrance materials, hydrophobically modified starches and combination thereof; and
a silicone gum having a concentration from 0.1% to 1.5% by weight of the antiperspirant composition.

2. The aerosol antiperspirant composition according to claim 1, wherein the one or more liquid materials of the antiperspirant composition consist essentially of one or more non-volatile silicone fluids.

3. The aerosol antiperspirant composition according to claim 1, wherein the one or more non-antiperspirant active particulate is a particulate fragrance material having a concentration from about 0.25% to about 5% by weight of the antiperspirant composition.

4. The aerosol antiperspirant composition according to claim 1, further comprising a liquid fragrance material having a concentration less than 4% by weight of the antiperspirant composition.

5. The aerosol antiperspirant composition according to claim 1, wherein the propellant has a concentration from 70% to 90% and the silicone gum has a concentration from 0.1% to 0.6%, by weight of the antiperspirant composition.

6. The aerosol antiperspirant composition according to claim 1, wherein the antiperspirant composition comprises a ratio of the concentration of the total non-volatile liquid materials to the concentration of the total particulate materials is from about 0.6 to about 1.6.

7. The aerosol antiperspirant composition according to claim 1, wherein the liquid materials comprise less than 10% by weight of volatile silicone fluids.

8. The aerosol antiperspirant composition according to claim 7, wherein the antiperspirant composition is substantially free of volatile silicone fluids.

9. The aerosol antiperspirant composition according to claim 1, wherein the antiperspirant composition has a viscosity greater than 3,000 centipoises at 25° C.

10. The aerosol antiperspirant composition according to claim 1, wherein the antiperspirant composition is substantially free of quartenary ammonium functional silicones.

11. The aerosol antiperspirant composition according to claim 1, wherein the antiperspirant composition is substantially free of functionalized siloxanes capable of reacting with the antiperspirant active particulates via an acid base or chelation reaction.

12. The aerosol antiperspirant composition according to claim 1, wherein the ratio of the concentration of the antiperspirant active particulate to the concentration of the total particulate is less than or equal to about 0.75.

13. The aerosol antiperspirant composition according to claim 12, wherein the ratio of the concentration of the antiperspirant active particulate to the concentration of the total particulate is from 0.1 to 0.75.

14. The aerosol antiperspirant composition according to claim 1, wherein the antiperspirant active particulates have a concentration from 16% to 32%, by weight of the antiperspirant composition.

15. The aerosol antiperspirant composition according to claim 1, wherein the non-volatile silicone fluids consist essentially of a polydimethyl siloxane fluid having a viscosity of 5 centistokes to 350 centistokes at 25° C.

16. A product, comprising a reservoir, an actuator comprising an actuator orifice, and a valve in fluid communication with the actuator orifice and the reservoir, the reservoir storing an aerosol antiperspirant composition according to claim 1.