EP2908799A1

EP2908799A1 - Soft solid antiperspirant compositions including soy wax and methods of preparing the same

Info

Publication number: EP2908799A1
Application number: EP13847043.0A
Authority: EP
Inventors: Travis T. Yarlagadda; Haley AUSTIN
Original assignee: Dial Corp
Current assignee: Dial Corp
Priority date: 2012-10-16
Filing date: 2013-09-27
Publication date: 2015-08-26
Also published as: WO2014062362A1; EP2908799A4

Abstract

Soft solid antiperspirant compositions and methods of preparing a soft solid antiperspirant composition are provided herein. The soft solid antiperspirant composition includes a hydrophobic carrier, an antiperspirant active component, a nucleating component, and a gellant. The nucleating component includes soy wax, and the gellant includes a C14 to C18 fatty alcohol component. The soft solid antiperspirant composition has a hardness of from about 10 to about 110 grams force. A method of preparing a soft solid antiperspirant composition includes combining a hydrophobic carrier, an antiperspirant active component, a nucleating component including soy wax, and a gellant including a C14 to C18 fatty alcohol component to form a gellant pre-mix, followed by heating to a melt temperature sufficient to melt the nucleating component. The heated antiperspirant pre-mix is mixed to form an antiperspirant composition, which is transferred into a receptacle to form the soft solid antiperspirant composition.

Description

SOFT SOLID ANTIPERSPIRANT COMPOSITIONS INCLUDING SOY WAX AND METHODS OF PREPARING THE SAME

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims priority to U. S. Utility Application 13/653,070 filed October 16, 2012 and entitled "SOFT SOLID ANTIPERSPIRANT COMPOSITIONS INCLUDING SOY WAX AND METHODS OF PREPARING THE SAME", which is incorporated herein.

TECHNICAL FIELD

[0002] The technical field generally relates to soft solid antiperspirant compositions and methods of preparing the soft solid antiperspirant compositions. More particularly, the technical field relates to soft solid antiperspirant compositions having a novel nucleating component, and methods of preparing the soft solid antiperspirant compositions including the novel nucleating component that provides unique manufacturing dynamics while still enabling hardness to be achieved within a desired range for soft solid antiperspirant compositions.

BACKGROUND

[0003] Antiperspirants are popular personal care products used to prevent perspiration and body odor caused by perspiration. Antiperspirants typically prevent the secretion of perspiration by blocking or plugging perspiration-secreting glands, such as those located at the underarms. Antiperspirant stick compositions are desired by a large majority of the population because of the presence of antiperspirant active compounds that block or prevent the secretion of perspiration and the accompanying odors thereof and because of their ease of application. The antiperspirant stick compositions are applied to the skin by swiping or rubbing the stick across the skin, typically of the underarm. However, antiperspirant users often are disappointed in the chalky, brittle, and/or crumbly application of the stick across the skin.

[0004] To reduce the chalky, brittle, and/or crumbly application of the antiperspirant stick compositions across the skin, one alternative form of antiperspirant composition that has been developed is a soft solid antiperspirant composition. Soft solid antiperspirant compositions generally resemble a blend between antiperspirant suspension compositions, which are generally applied to skin through roll-on application, and invisible solid antiperspirant stick compositions. Soft solid antiperspirant compositions are typically identified by their hardness, which can range from about 10 to about 110 grams force, and the soft solid antiperspirant composition are generally applied through extrusion of the soft solid antiperspirant composition through a grid of perforated holes on an application surface of a package or as a lotion.

[0005] Because the primary difference between solid antiperspirant compositions and soft solid antiperspirant compositions is generally hardness of the compositions, ingredients used to formulate solid antiperspirant compositions may not be suitable to formulate soft solid antiperspirant compositions. Desired hardness for soft solid antiperspirant compositions may not be achievable without modifying the formulation of the solid antiperspirant compositions. Hardness may be influenced by a variety of components, including gellants, such as fatty acids, and a nucleating component, such as one or more waxes, that are included in both the solid antiperspirant compositions and the soft solid antiperspirant compositions. Castor wax is a common nucleating compound. Compounds present as part of the nucleating component precipitate out of a melt of the soft solid antiperspirant composition prior to the gellant during cooling. Because the nucleating component is generally first to precipitate during cooling of the melt, the nucleating component provides nucleation sites for crystal formation by the gellant within the antiperspirant compositions as the melt cools. The resulting crystal structure within the antiperspirant compositions impacts hardness, with longer, unidirectional crystal structures corresponding to harder antiperspirant compositions. Hardness may also be influenced by processing conditions, such as temperatures at which the antiperspirant compositions are melted (i.e., melt temperature) and poured (i.e., pour temperature) into receptacles that are suitable for consumer use. The melt temperature and pour temperature may impact the rate and length of crystal formation by affecting precipitation of the nucleating component out of the melt.

[0006] Conventional soft solid antiperspirant compositions, such as those including castor wax as the sole nucleating compound, generally require low pour temperatures to obtain a sufficiently low hardness. To achieve lower pour temperatures for conventional soft solid antiperspirant compositions, dedicated processing apparatuses that are adapted to sufficiently cool the conventional soft solid antiperspirant compositions may be required. In particular, different processing apparatuses may be required for conventional soft solid antiperspirant compositions than processing apparatuses that are employed for similar solid antiperspirant compositions, which represents a manufacturing inefficiency.

[0007] Even if a dedicated processing apparatus is employed to prepare the soft solid antiperspirant compositions, to effectively vary hardness of the soft solid antiperspirant compositions into acceptable ranges from corresponding solid antiperspirant compositions, the amount and type of nucleating component present in the antiperspirant composition may require modification, thus requiring extensive efforts to maintain other similar characteristics between the various forms of the antiperspirant compositions, such as antiperspirant efficacy, appearance, and scent, while only modifying the hardness of the antiperspirant compositions. Further, if initial samples of the soft solid antiperspirant composition tested out of the processing apparatus are out of specification for hardness, the remaining soft solid antiperspirant composition in a batch or formulation of the soft solid antiperspirant composition will likely be out of specification unless altered. Post alteration of the soft solid antiperspirant compositions is difficult and time consuming.

[0008] Accordingly, it is desirable to provide soft solid antiperspirant compositions having a lower hardness than that of conventional solid antiperspirant compositions. In addition, it is desirable to provide soft solid antiperspirant compositions that can be prepared to have suitable low hardness when made in processing apparatuses that are also used for preparing solid antiperspirant compositions. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with this background of the invention.

BRIEF SUMMARY

[0009] Soft solid antiperspirant compositions and methods of preparing a soft solid antiperspirant composition are provided herein. In an embodiment, a soft solid antiperspirant composition includes a hydrophobic carrier, an antiperspirant active component, a nucleating component, and a gellant. The nucleating component includes soy wax, and the gellant includes a C14 to C18 fatty alcohol component. The soft solid antiperspirant composition has a hardness of from about 10 to about 110 grams force.

[0010] In another embodiment, a soft solid antiperspirant composition includes a hydrophobic carrier, an antiperspirant active component, a nucleating component, and a gellant. The hydrophobic carrier is present in an amount of from about 25 to about 65 weight %, based upon a total weight of the soft solid antiperspirant composition. The antiperspirant active component is present in an amount of from about 10 to about 25 weight %, based upon a total weight of the soft solid antiperspirant composition. The gellant includes a C14 to C18 fatty alcohol component. The nucleating component is present in an amount of from about 1 to about 10 weight %, based upon a total weight of the soft solid antiperspirant composition, and the nucleating component includes soy wax in an amount of at least 75 weight % based on a total weight of the nucleating component. A weight ratio of soy wax to all fatty alcohols in the soft solid antiperspirant composition is from about 1:7.5 to about 1 :1.5.

[0011] In another embodiment, a method of preparing a soft solid antiperspirant composition includes combining a nucleating component including soy wax and a gellant including a C14 to C18 fatty alcohol component to form a gellant pre-mix. The gellant pre-mix is heated to a melt temperature sufficient to melt the nucleating component. The heated gellant pre-mix is mixed to form a gellant mixture, followed by combining a hydrophobic carrier, an antiperspirant active component, and the gellant mixture to form an antiperspirant composition. The antiperspirant composition is transferred into a receptacle to form the soft solid antiperspirant composition. DETAILED DESCRIPTION

[0012] The following detailed description is merely exemplary in nature and is not intended to limit the invention or the application and uses of the invention. Furthermore, there is no intention to be bound by any theory presented in the preceding background or the following detailed description.

[0013] Soft solid antiperspirant compositions and methods of preparing the soft solid antiperspirant compositions are provided. The soft solid antiperspirant compositions include a hydrophobic carrier, an antiperspirant active component, a nucleating component that includes soy wax, and a gellant that includes a C14 to C18 fatty alcohol component. The combination of the aforementioned constituents in the soft solid antiperspirant composition, particularly the presence of the soy wax in the nucleating component, enables the soft solid antiperspirant compositions to have a hardness of from about 10 to about 110 grams force (gF), such as from about 30 to 60 gF, which is within a range of generally- accepted hardness values for soft solid antiperspirant compositions. Further, by including the soy wax in the nucleating component, an unexpected inverse relationship between pour temperature and hardness of the soft solid antiperspirant compositions is achieved. Whereas conventional soft solid antiperspirant compositions require low pour temperatures to obtain a sufficiently low hardness, higher pour temperatures either result in an immaterial change or a decrease in hardness for the instant soft solid antiperspirant compositions that include the soy wax in the nucleating component. To achieve lower pour temperatures for conventional soft solid antiperspirant compositions, dedicated processing apparatuses that are adapted to sufficiently cool the conventional soft solid antiperspirant compositions may be required, whereas no such requirement exists to achieve sufficiently low hardness for the soft solid antiperspirant compositions described herein.

[0014] As set forth above, the soft solid antiperspirant compositions include the hydrophobic carrier, and may include a combination of hydrophobic carriers. As referred to herein, "hydrophobic" refers to compounds that lack polar groups and, therefore, are insoluble in water. Suitable hydrophobic carriers for soft solid antiperspirant compositions are known in the art. Examples of suitable hydrophobic carriers include liquid siloxanes and volatile polyorganosiloxanes. Examples of suitable silicone carrier fluids include liquid siloxanes and, particularly, volatile polyorganosiloxanes having a measurable vapor pressure at ambient conditions. By "volatile", it is meant that the materials have a measurable vapor pressure at ambient conditions. The volatile polyorganosiloxanes can be linear, cyclic, or mixtures thereof. The linear volatile polyorganosiloxanes generally have viscosities of less than about 5 centistokes at 25°C, while the cyclic volatile polyorganosiloxanes have viscosities under 10 centistokes at 25°C. Specific examples of volatile polyorganosiloxanes include cyclomethicones, which have from about 3 to about 6 silicon atoms, such as cyclotetramethicone, cyclopentamethicone, and cyclohexamethicone, and mixtures thereof. The hydrophobic carrier may also include, in addition to or as an alternative to the liquid siloxanes and volatile polyorganosiloxanes, nonvolatile silicones such as dimethicone and dimethicone copolyols, which have from about 2 to about 9 silicon atoms. Examples of suitable dimethicone and dimethicone copolyols include polyalkyl siloxanes, polyalkylaryl siloxanes, and polyether siloxane copolymers. However, in an embodiment, such nonvolatile silicones are present in a total amount of less than or equal to 1% by weight based upon the total weight of the soft solid antiperspirant composition to avoid excessive residual wetness after the soft solid antiperspirant composition dries. In an embodiment, the hydrophobic carrier is present in an amount of from about 25 to about 65 weight %, for example, from about 40 to about 55 weight %, based upon the total weight of the antiperspirant composition.

[0015] The antiperspirant active component is not limited and any known antiperspirant active compound can be included in the soft solid antiperspirant composition that is known in the art for including in solid or soft solid antiperspirant compositions. As referred to herein, the "antiperspirant active component" represents all antiperspirant active compounds that are present in the soft solid antiperspirant composition. Antiperspirant active compounds are known in the art. Examples of suitable antiperspirant active compounds include astringent water-soluble inorganic and organic salts of aluminum, zirconium and zinc or any mixtures of these salts. In accordance with the instant application, water-solubility refers to a solubility of at least 5% by weight at 20° C. (i.e., at least 5 g of active antiperspirant compound is soluble in 95 g of water at 20° C), with compounds having less solubility than 5% by weight at 20° C being water-insoluble.

[0016] Examples of suitable antiperspirant active compounds that may be used include astringent metallic salts, especially inorganic and organic salts of aluminum, zirconium, and zinc, as well as mixtures thereof. Suitable aluminum-containing and/or zirconium- containing salts or materials include, for example, aluminum halides, aluminum chlorohydrates, aluminum hydroxyhalides, zirconyl oxyhalides, zirconyl hydroxyhalides, and mixtures thereof. Exemplary aluminum salts include those having the general formula Al₂(OH)_aCl_b x (¾0), wherein a is from 2 to about 5; the sum of a and b is about 6; x is from about 1 to about 6; and wherein a, b, and x may have non-integer values. Exemplary zirconium salts include those having the general formula ZrO(OH)_2-aCl_a x (¾0), wherein a is from about 1.5 to about 1.87, x is from about 1 to about 7, and wherein a and x may both have non-integer values. Specific examples of suitable zirconium salts are those complexes that additionally contain aluminum and glycine, commonly known as ZAG complexes. These ZAG complexes contain aluminum chlorohydroxide and zirconyl hydroxy chloride conforming to the above-described formulas. Examples of active antiperspirant compounds suitable for use in the various embodiments contemplated herein include aluminum dichlorohydrate, aluminum-zirconium octachlorohydrate, 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-zirconium trichlorohydrate, aluminum zirconium tetrachlorohydrate, aluminum zirconium pentachlorohydrate, aluminum zirconium octachlorohydrate, aluminum zirconium trichlorohydrex glycine complex, aluminum zirconium tetrachlorohydrex glycine complex, aluminum zirconium pentachlorohydrex glycine complex, aluminum zirconium octachlorohydrex glycine complex, zirconium chlorohydrate, aluminum chloride, aluminum sulfate buffered, and the like, and mixtures thereof.

[0017] The antiperspirant active component is present in the soft solid antiperspirant composition in an amount that provides a measurable antiperspirant effect when applied to the underarms of a consumer. In an embodiment, the antiperspirant active component is present in an amount of from about 10 to about 25 weight %, for example, from 15 to 25 weight %, based upon the total weight of the antiperspirant composition. It is to be appreciated that the above values represent the total amount of all antiperspirant active compounds present in the soft solid antiperspirant composition. It is also to be appreciated that most commercially available antiperspirant active compounds are sold in mixtures along with other compounds that are not considered antiperspirant active compounds, and the above values account for the presence of such non-active antiperspirant compounds. When sold in mixtures, the antiperspirant active composition includes antiperspirant active compounds in an amount of from about 30 to about 99 weight %, such as from about 50 to about 85 weight %, based on the total weight of the antiperspirant active component.

[0018] As set forth above, the soft solid antiperspirant composition further includes the nucleating component that includes soy wax. One example of a suitable soy wax is a hydrogenated soy polyglyceride and a CI 5 to C23 alkane mixture commercially available under the tradename Dow Corning® HY-3050 Soy Wax from Dow Corning Corporation of Midland, MI. The nucleating component, as referred to herein, optionally includes additional compounds that are solid at ambient temperature of about 21°C, have a melting point within about 15°C of a melting point of the gellant, and a solubility in the hydrophobic carrier that is less than the gellant (as described in further detail below). In this regard, when the soft solid antiperspirant composition is melted to mix the components therein, all compounds present in the soft solid antiperspirant composition as part of the nucleating component precipitate out of a melt of the soft solid antiperspirant composition prior to the gellant during cooling. Because the nucleating component is generally first to precipitate during cooling of the melt, the nucleating component provides nucleation sites for crystal formation by the gellant within the soft solid antiperspirant composition as the melt cools. With the presence of soy wax in the soft solid antiperspirant composition, as at least part of the nucleating component, it was unexpectedly found that the soft solid antiperspirant compositions exhibit an inverse relationship between pour temperature and hardness of the soft solid antiperspirant compositions, which provides numerous processing benefits. Because pour temperature is marginalized by the presence of soy wax, solid antiperspirant compositions can be readily modified into corresponding soft solid antiperspirant compositions, thereby enabling a range of similar-performing antiperspirant products to be manufactured in different physical forms. For example, a branded solid antiperspirant composition having a particular scent and antiperspirant performance can be readily modified, through the inclusion or substitution of soy wax as at least a part of the nucleating component, into a soft solid antiperspirant composition. Even more, soft solid antiperspirant compositions including the soy wax as at least part of the nucleating component can be prepared in common processing apparatuses with the corresponding solid antiperspirant compositions, as described in further detail below, even further adding to the processing benefits.

[0019] In an embodiment, the nucleating component includes, in addition to soy wax, one or more additional nucleating compounds. Various nucleating compounds are known in the art, including but not limited to those chosen from esters of fatty alcohols, ethoxylated fatty alcohols, esters or ethers of fatty acids including waxes, and triglycerides, solid polyol carboxylic acid polyesters, and mixtures thereof. In this embodiment, the nucleating component includes the soy wax in an amount of at least 75 weight %, such as from about 75 to about 99 weight % based on a total weight of the nucleating component, with the balance of the nucleating component being one or more of the aforementioned nucleating compounds, provided that the particular nucleating compound meets the aforementioned performance characteristics relative to the gellant. In another embodiment, the nucleating component includes soy wax and one or more additional nucleating compounds, provided that the soft solid antiperspirant composition is free from castor wax. By "free", as referred to herein, it is meant that the referenced component is below an amount that visually or by instrument noticeably alters any property of the antiperspirant composition. Castor wax, including hydrogenated castor oil, is a common nucleating component for solid antiperspirant compositions, but when used as the sole nucleating component, is incapable of imparting antiperspirant compositions with sufficiently low hardness to be considered soft solid antiperspirant compositions. In another embodiment, the nucleating component, as well as the entire soft solid antiperspirant composition, is free from silica and derivatives thereof. In another embodiment, the nucleating component only includes soy wax. In this embodiment, the soft solid antiperspirant composition is free from additional components that provide nucleation sites for crystal formation by the gellant, such as castor wax or any of the aforementioned known nucleating components that have the aforementioned performance characteristics relative to the gellant. The nucleating component is generally present in an amount of from about 1 to about 10 weight %, such as from about 1 to about 8 weight %, based on the total weight of the soft solid antiperspirant composition. The soy wax is generally present in an amount of from about 1 to about 8 weight %, based on the total weight of the soft solid antiperspirant composition.

[0020] As set forth above, the soft solid antiperspirant composition further includes the gellant that includes the C14 to CI 8 fatty alcohol component. As used herein, the term "fatty" means a long chain aliphatic group that can be branched or unbranched, and that can further be saturated or unsaturated. As known in the art and as referred to herein, the gellant is a compound or combination of compounds that form crystals from nucleation sites, such as those provided by the nucleating component. The resulting crystals form a crystalline matrix within which the hydrophobic carrier or other liquid component(s) of the soft solid antiperspirant composition is contained. In an embodiment, the C 14 to CI 8 fatty alcohol component includes stearyl alcohol, cetyl alcohol, myristyl alcohol, or a combination thereof. In another embodiment, the soft solid antiperspirant composition is substantially free of fatty alcohols having less than about 14 carbon atoms due to potential instability of the soft solid antiperspirant compositions at elevated temperatures, such as about 45 °C, when fatty alcohols having less than about 14 carbon atoms are present. In another embodiment, the gellant includes one chosen from myristyl alcohol, cetyl alcohol, stearyl alcohol, or a combination thereof. In another embodiment, the gellant only includes C14 to CI 8 fatty alcohols. The C14 to CI 8 fatty alcohol component is present in the soft solid antiperspirant composition in an amount of from about 8 to about 30 weight %, such as from about 15 to about 30 weight %, based on the total weight of the soft solid antiperspirant composition. In another embodiment, the gellant includes one or more additional compound that forms crystals from nucleation sites, similar to the performance of the C14 to CI 8 fatty alcohol. Examples of suitable additional compounds that may be included in the gellant include, but are not limited to, fatty alcohols having greater than 18 carbon atoms; hydrocarbon waxes such as paraffin waxes, microcrystalline waxes, ceresin, squalene, and polyethylene waxes; waxes derived or obtained from plants or animals such as hydrogenated soybean oil, carnabau, spermacetti, candelilla, beeswax, modified beeswaxes, and Montan wax. For example, in an embodiment, the gellant includes the C14 to CI 8 fatty alcohol component and microcrystalline wax. When the gellant includes one or more additional compounds in addition to the C 14 to CI 8 fatty alcohol component, the one or more additional compounds of the gellant may be present in an amount of from 0.5 to about 10 weight %, based on the total weight of the soft solid antiperspirant composition.

[0021] A weight ratio of soy wax to all fatty alcohols in the soft solid antiperspirant composition is from about 1 :7.5 to about 1 :1.5, such as from about 1 :5 to about 1 :2.5. Relative amounts of the soy wax to the fatty alcohols within the aforementioned ranges are sufficient to ensure that the desired hardness characteristics of soft solid antiperspirant compositions are obtained.

[0022] In addition to the aforementioned components, further additives may be included in the soft solid antiperspirant composition for various purposes including additives that cause the antiperspirant composition to exhibit long-lasting fragrance, odor protection, bacteria control, skin conditioning, white residue masking, and/or another desired purpose and/or function. Specific examples of additional such additives include, but are not limited to, fragrances, including encapsulated fragrances; skin conditioners; dyes; pigments; preservatives; antioxidants; moisturizers; suspending agents, and the like. These optional additives can be included in the antiperspirant composition in a total amount of from about 0 to about 20 weight %. Fragrance, for example, may be present in an amount of from about 0.1 to about 0.5 weight %, such as, from about 0.2 to about 0.3 weight %, based on the total weight of the soft solid antiperspirant composition. Skin conditioners, such as myristyl myristate, can be present in an amount of from about 0.5 to about 8 weight % based on the total weight of the soft solid antiperspirant composition. Examples of white residue-masking compounds include, but are not limited to, PPG-14 butyl ether, C12-C15 alkyl benzoate, and phenyl dimethicone. In an embodiment, the white residue-masking compound is present in an amount of from about 5 to about 15 weight % based on the total weight of the soft solid antiperspirant composition.

[0023] It is to be appreciated that the soft solid antiperspirant composition can be prepared in any manner known in the art for preparing soft solid antiperspirant compositions, and the soft solid antiperspirant composition is not limited in the manner in which it is prepared. In an embodiment of an exemplary method of preparing the soft solid antiperspirant composition, the nucleating component including the soy wax and the gellant including the CI 4 to CI 8 fatty alcohol component are mixed to form a gellant pre- mix in an appropriate processing apparatus for heating and mixing the gellant pre-mix. In an embodiment, the antiperspirant active component is mixed with a portion of the hydrophobic carrier, separate from the gellant pre-mix, to form an antiperspirant pre-mix. The gellant pre-mix is heated to a melt temperature, and the heated gellant pre-mix is mixed to form a gellant mixture that includes the gellant and the nucleating component. The hydrophobic carrier, the antiperspirant active component, and the gellant mixture are combined to form an antiperspirant composition. In particular, the antiperspirant pre-mix, the gellant mixture, and remaining components including any remaining hydrophobic carrier are mixed to form the antiperspirant composition. The antiperspirant composition is maintained at a pour temperature followed by transferring the antiperspirant composition to a receptacle at the pour temperature to form the soft solid antiperspirant composition.

[0024] In an embodiment, the soft solid antiperspirant composition is prepared in a processing apparatus that includes a mixer and a heating device so that the temperature of the gellant pre-mix can be sufficiently increased to melt the nucleating component and the gellant. The processing apparatus may further include a chilling device for cooling the soft solid antiperspirant composition to a pour temperature after sufficiently mixing the soft solid antiperspirant composition in anticipation of transferring the soft solid antiperspirant composition into a receptacle. However, as set forth above, the soft solid antiperspirant compositions described herein exhibit an inverse relationship between pour temperature and hardness such that cooling of the soft solid antiperspirant compositions to low pour temperatures, as is required to obtain sufficiently low hardness for conventional soft solid antiperspirant compositions, has little impact on the hardness of the soft solid antiperspirant compositions as described herein. As such, processing apparatuses that are employed to prepare solid antiperspirant compositions can be employed to prepare the soft solid antiperspirant compositions described herein, without modifications to the processing apparatuses to enable cooling to lower pour temperatures that are customarily employed for conventional soft solid antiperspirant compositions. In accordance with an embodiment, a solid antiperspirant composition is also prepared in the processing apparatus separate from preparation of the soft solid antiperspirant composition, thus illustrating the manufacturing flexibility afforded by the soft solid antiperspirant compositions described herein because the same processing apparatus can be used that is used for preparing solid antiperspirant compositions.

[0025] As set forth above, the gellant pre-mix is heated to a melt temperature. The melt temperature is sufficient to melt at least the nucleating component, thereby enabling the nucleating component to be dispersed in anticipation of crystal formation upon precipitation of the nucleating component from the melt. In an embodiment, the gellant pre-mix is heated to a melt temperature of greater than about 52°C, such as from about 52°C to about 100°C, to melt the nucleating component. In an embodiment, the melt temperature is greater than the pour temperature, as described in further detail below. During or after heating the gellant pre-mix, optionally commencing before heating the gellant pre-mix, the heated gellant pre-mix is mixed to form the gellant mixture.

[0026] After a sufficient period of mixing to uniformly disperse the components in the gellant mixture, the remaining components are combined with the gellant mixture to form the antiperspirant composition, which is maintained at a pour temperature. "Pour temperature" is herein defined as a temperature of the antiperspirant composition when transferred into a receptacle such as a consumer package. In an embodiment, the antiperspirant composition is maintained at a pour temperature of at least 32°C, such as from about 32 to about 62°C. For example, in an embodiment, the antiperspirant composition is maintained at a pour temperature of at least 52°C, such as from about 55 to about 58°C, which temperatures are higher than customary pour temperatures for conventional soft solid antiperspirant compositions that enable the conventional soft solid antiperspirant compositions to be sufficiently soft. It is to be appreciated that the pour temperature is less than the melt temperature. Pour temperatures within the above ranges enable the processing apparatuses to be employed that are also used to prepare solid antiperspirant compositions because excessive cooling is unnecessary to obtain the desired hardness of the soft solid antiperspirant compositions that are described herein.

[0027] As alluded to above, the antiperspirant composition is transferred into a receptacle to form the soft solid antiperspirant composition. In particular, the antiperspirant composition is transferred into the receptacle at the pour temperature to form the soft solid antiperspirant composition. The antiperspirant composition crystallizes in the receptacle, with the nucleating component first precipitating out of the antiperspirant composition followed by crystal growth of the gellant from the nucleating component. In an embodiment, the receptacle is a consumer package that facilitates application of the soft solid antiperspirant composition. Alternatively, the receptacle is an intermediate container that receives the antiperspirant composition and in which the antiperspirant composition crystallizes to form the soft solid antiperspirant composition that has the hardness as described above.

EXAMPLES

[0028] Soft solid antiperspirant compositions were prepared in accordance with the aforementioned method. In particular, the antiperspirant active component and a portion of the hydrophobic carrier were first mixed to form an antiperspirant pre-mix. Separately, the nucleating compound and gellants were combined in a vessel to form a gellant pre-mix. The gellant pre-mix was heated to a temperature of about 95°C, mixed for a period of about 10 minutes, and then cooled to a temperature of about 65 °C to form a gellant mixture. The antiperspirant pre-mix, the remaining hydrophobic carrier, and the other components were then combined with the gellant mixture in the vessel to form an antiperspirant composition. Table I provides an account of the various components and amounts thereof, with all amounts based on the total amount of the antiperspirant composition.

TABLE I

Gellant E 1.80 1.80 1.80 1.80 1.80

Nucleating Compound A 4.00 4.00 4.00 4.00 4.00

Skin Conditioner 1.92 1.92 1.92 1.92 1.92

White Residue-Masking Compound 10.00 10.00 10.00 10.00 10.00

Fragrance 1.50 1.50 1.50 1.50 1.50

Surfactant 0.00 0.00 2.00 0.00 0.00

Total 100.00 100.00 100.00 100.00 100.00

[0029] Antiperspirant Active Component A is an aluminum zirconium trichlorohydrex glycine complex commercially available under the tradename Zirconal® from BK Giulini GmbH of Simi Valley, CA.

[0030] Hydrophobic Carrier A is DC245 Silicone Fluid commercially available from

Dow Corning Corporation of Midland, MI.

[0031] Gellant A is solid stearyl alcohol.

[0032] Gellant B is cetyl alcohol.

[0033] Gellant C is myristyl alcohol.

[0034] Gellant D is microcrystalline wax.

[0035] Gellant E is polyethylene wax.

[0036] Nucleating Compound A is soy wax including a hydrogenated soy polyglyceride and CI 5 to C23 alkane mixture commercially available from Dow Corning Corporation.

[0037] Skin Conditioner is myristyl myristate.

[0038] White Residue-Masking Compound is PPG-14 butyl ether.

[0039] Surfactant is a PEG-7 glyceryl cocoate surfactant commercially available from

Cognis Corporation.

[0040] The antiperspirant composition was maintained at a pour temperature of either 52°C, 42°C, or 32°C in the vessel, followed by transferring the antiperspirant composition into a receptacle at the stated pour temperature to form the soft solid antiperspirant compositions. Hardness of the soft solid antiperspirant compositions was then measured after 1 hour, when the soft solid antiperspirant compositions were cooled to about 21 °C. Hardness of the soft solid antiperspirant compositions was measured using a texture analyzer device (Texture Analyzer XT Express commercially available from Texture Technology Corporation of Scarsdale, NY) by contacting a surface of the soft solid antiperspirant composition with a probe (30° cone). Once the probe has penetrated the surface of the soft solid antiperspirant composition (as indicated by sensing a 5 grams force (gF) trigger), the texture analyzer begins measuring additional force that is required to continue to push the probe at a rate of 1 mm/second to a depth of 5mm within the soft solid antiperspirant composition. The average gF that is measured during the test is recorded as the hardness of the soft solid antiperspirant composition. Hardness, in grams force (gF), of two samples from each of the above Examples is provided in Table II below corresponding to pour temperatures of 52°C, 42°C, and 32°C.

TABLE II

[0041] A comparative antiperspirant composition was also prepared in accordance with the method described above, with the comparative antiperspirant composition including the components set forth in Table III. All amounts are in percent by weight based upon the total weight of the comparative antiperspirant composition. TABLE III

[0042] Antiperspirant Active Component B is an aluminum zirconium pentachlorohydrex glycine complex commercially available under the tradename AAZG-

3110 from Summit Reheis of Huguenot, NY.

[0043] Hydrophobic Carrier A cyclopentasiloxane.

[0044] Nucleating Compound B is hydrogenated castor oil.

[0045] Suspending Agent A is silica dimethyl silylate.

[0046] Suspending Agent B is silica.

[0047] Hardness of the comparative antiperspirant composition was measured at various pour temperatures, and Table IV provides the measured hardness, in gF, corresponding to pour temperatures of 55, 53, 51, and 49.7°C, with the values representing a mean hardness, in gF, as measured on 10 samples poured at each temperature.

TABLE IV

[0048] While at least one exemplary embodiment has been presented in the foregoing detailed description of the invention, it should be appreciated that a vast number of variations exist. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. Rather, the foregoing detailed description will provide those skilled in the art with a convenient road map for implementing an exemplary embodiment of the invention. It being understood that various changes may be made in the function and aiTangement of elements described in an exemplary embodiment without departing from the scope of the invention as set forth in the appended claims.

Claims

CLAIMS What is claimed is:

1. A soft solid antiperspirant composition comprising:

a hydrophobic carrier;

an antiperspirant active component;

a nucleating component comprising soy wax;

a gellant comprising a C14 to C18 fatty alcohol component;

wherein the soft solid antiperspirant composition has a hardness of from about 10 to about 110 grams force.

2. The soft solid antiperspirant composition of claim 1, wherein the nucleating component comprises the soy wax in an amount of at least 75 weight % based on a total weight of the nucleating component.

3. The soft solid antiperspirant composition of claim 2, wherein the soft solid antiperspirant composition is free from castor wax.

4. The soft solid antiperspirant composition of claim 3, wherein the nucleating component consists of the soy wax, and wherein the soft solid antiperspirant composition is free from additional components that provide nucleation sites for crystal formation by the gellant.

5. The soft solid antiperspirant composition of claim 1, wherein the nucleating component comprises one or more waxes in addition to the soy wax with each compound in the nucleating component being solid at ambient temperature of about 21 °C, having a melting point within about 15°C of a melting point of the gellant, and a solubility in the hydrophobic carrier that is less than the gellant.

6. The soft solid antiperspirant composition of claim 1, wherein a weight ratio of soy wax to all fatty alcohols in the soft solid antiperspirant composition is from about 1:7.5 to about 1 : 1.5.

7. The soft solid antiperspirant composition of claim 1, wherein the gellant comprises one chosen from myristyl alcohol, cetyl alcohol, and stearyl alcohol.

8. The soft solid antiperspirant composition of claim 1, wherein the gellant further comprises microcrystalline wax.

9. The soft solid antiperspirant composition of claim 1, wherein the hydrophobic carrier comprises a cyclomethicone.

10. The soft solid antiperspirant composition of claim 1, wherein:

the hydrophobic carrier is present in an amount of from about 25 to about 65 weight %;

the antiperspirant active component is present in an amount of from about 10 to about 25 weight %;

the nucleating component is present in an amount of from about 1 to about 10 weight %; and

the C14 to CI 8 fatty alcohol component is present in an amount of from about 8 to about 30 weight %;

wherein all amounts are in weight % based upon a total weight of the soft solid antiperspirant composition.

11. A soft solid antiperspirant composition comprising:

a hydrophobic carrier present in an amount of from about 25 to about 65 weight %, based upon a total weight of the soft solid antiperspirant composition;

an antiperspirant active component present in an amount of from about 10 to about 25 weight %, based upon a total weight of the soft solid antiperspirant composition;

a gellant comprising a C14 to C18 fatty alcohol component; a nucleating component present in an amount of from about 1 to about 10 weight %, based upon a total weight of the soft solid antiperspirant composition, the nucleating component comprising soy wax in an amount of at least 75 weight % based on a total weight of the nucleating component;

wherein a weight ratio of soy wax to all fatty alcohols in the soft solid antiperspirant composition is from about 1:7.5 to about 1:1.5.

12. A method of preparing a soft solid antiperspirant composition, the method comprising:

combining a nucleating component comprising soy wax and a gellant comprising a C14 to CI 8 fatty alcohol component to form a gellant pre-mix;

heating the gellant pre-mix to a melt temperature sufficient to melt the nucleating component;

mixing the heated gellant pre-mix to form a gellant mixture;

combining a hydrophobic carrier, an antiperspirant active component, and the gellant mixture to form an antiperspirant composition, and

transferring the antiperspirant composition into a receptacle to form the soft solid antiperspirant composition.

13. The method of claim 12, further comprising maintaining the antiperspirant composition at a pour temperature and transfemng the antiperspirant composition at the pour temperature into the receptacle to form the soft solid antiperspirant composition.

14. The method of claim 13, wherein maintaining the antiperspirant composition at the pour temperature comprises maintaining the antiperspirant composition at a pour temperature of at least 32°C.

15. The method of claim 13, wherein maintaining the antiperspirant composition at the pour temperature comprises maintaining the antiperspirant composition at a pour temperature of at least 52°C.

16. The method of claim 13, wherein heating the gellant pre-mix comprises heating the gellant pre-mix to the melt temperature that is greater than the pour temperature.

17. The method of claim 16, wherein heating the gellant pre-mix comprises heating the gellant pre-mix to a melt temperature of greater than 52°C, and wherein maintaining the antiperspirant composition at the pour temperature comprises maintaining the antiperspirant composition at a pour temperature of at least 52°C, provided the pour temperature is less than the melt temperature.

18. The method of claim 12, wherein combining the nucleating component and the gellant comprises combining the soy wax in an amount of at least 75 weight % based on a total weight of the nucleating component and in a weight ratio of soy wax to all fatty alcohols in the soft solid antiperspirant composition of from about 1 :7.5 to about 1 :1.5.

19. The method of claim 12, wherein the soft solid antiperspirant composition is prepared in a processing apparatus comprising a mixer and a chilling device.

20. The method of claim 19, further comprising preparing a solid antiperspirant composition in the processing apparatus separate from preparation of the soft solid antiperspirant composition.