Packaged antiperspirant cream composition

Disclosed is a packaged antiperspirant cream composition comprising a gellant, a liquid carrier, an antiperspirant active, and a dispensing package which contains the antiperspirant cream composition. The packaged antiperspirant cream compositions have improved stability, application aesthetics, and reduced syneresis. The dispensing package comprises 1) a container body having an interior chamber of generally uniform or symmetrical cross section which contains the antiperspirant cream composition and has a lengthwise extending axis, 2) an elevator having a cross section congruent to and mounted for axial movement within the interior chamber, 3) a perforated, convex dome attached to a dispensing end of the container body and having a plurality openings extending through the thickness of the perforated dome, 4) a means for axially advancing the elevator toward the perforated dome; and 5) an optional means for axially reciprocating the elevator away from the convex dome; wherein the means for axially advancing the elevator and the optional means for axially reciprocating the elevator cooperate to reciprocate the elevator a minimum distance D.sub.min. The dispensing package preferably has a select container body rigidity, a select convex configuration for the perforated dome and supporting elevator, and/or other means for reducing residual internal pressure, all of which help to minimize the development of solvent syneresis from the antiperspirant cream composition.

TECHNICAL FIELD 
The present invention relates to packaged antiperspirant cream compositions 
which provide improved spreading and product stability. In particular, the 
present invention relates to packaged antiperspirant cream compositions 
having a select package configuration that provides improved product 
stability and application performance. 
BACKGROUND OF THE INVENTION 
There are many types of topical antiperspirant products that are 
commercially available or otherwise known in the antiperspirant art. Most 
of these products are formulated as sprays, roll-on liquids, creams, or 
solid sticks, and comprise an astringent material, e.g. zirconium or 
aluminum salts, incorporated into a suitable topical carrier. These 
products are designed to provide effective perspiration and odor control 
while also being cosmetically acceptable during and after application onto 
the underarm area or other areas of the skin. 
Within this product group, antiperspirant creams have become increasingly 
more popular as an effective alternative to antiperspirant sprays and 
solid sticks. These creams can be applied by conventional means, or 
packaged into topical dispensers to make topical application more 
efficient and less messy. Perspiration and odor control provided by these 
products can be excellent. Many of these creams, however, are cosmetically 
unacceptable to a large number of antiperspirant users. Application of 
these creams can be messy, difficult to spread and wash off, and even when 
a cream applicator is employed, the applied areas often feel wet or sticky 
for several minutes after application. These compositions are especially 
difficult to uniformly spread over hairy areas of the skin. Many consumers 
have therefore preferred antiperspirant sticks for ease of administration 
and drier skin feel immediately after application, although the 
antiperspirant sticks typically leave an undesirably high residue on the 
skin. 
One method for making improved antiperspirant creams involves the 
formulation of particulate antiperspirant actives in a mixture of volatile 
and nonvolatile silicones or other carriers. The use of such volatile 
solvents in these mixtures helps reduce stickiness, improve dry-own times 
after application onto skin, improve ease of spreading, and improve 
wash-off characteristics. To maintain physical stability of these creams, 
however, inorganic thickening agents such as bentonite clays, hectorite 
clays, colloidal or fumed silicas are often needed. The inorganic 
thickening agents, however, contribute a grainy texture to the product and 
are not especially effective in maintaining physical stability when higher 
concentrations of volatile silicone or nonsilicone solvents, or lower 
viscosity nonvolatile silicone or nonsilicone solvents are used. This 
physical instability results in solvent syneresis (weeping of solvent from 
the cream matrix) during packaging, storage or shipping. 
Product instability in the form of solvent syneresis can be minimized or 
eliminated in these soft creams by simply formulating the product into a 
harder, more conventional, antiperspirant stick. Many consumers, however, 
prefer the lower residue cosmetics associated with the soft creams, 
especially when these creams are applied with a cream applicator device 
having a perforated dome through which the soft cream is extruded and 
applied to the skin. Antiperspirant sticks are too hard to be extruded 
through most perforated domes, and typically result in higher visible 
residue on the skin than soft antiperspirant creams. 
Other methods of preparing soft antiperspirant creams involve the use of 
compositions comprising a volatile silicone solvent, suitable gellant, and 
antiperspirant active, which compositions are prepared by select 
processing methods. Components of the compositions are mixed together and 
heated above the melt point of the gellant, and then cooled to below the 
normal solidification point of the composition while subjecting the 
composition to continuous mixing or shear. The continuous mixing or shear 
prevents the product from forming a solid matrix at its normal 
solidification point, and thus forms a soft creamy matrix with continuous 
mixing below its normal solidification point. The continuous mixing thus 
prevents the composition from solidifying into a harder gel stick, and 
thus transforms it into a soft cream instead. These compositions, however, 
tend to be physically unstable during storage and result in substantial 
solvent syneresis during storage, shipping or even during application of 
the soft cream when applied through a perforated dome. 
Recently, antiperspirant creams have been disclosed which do not rely upon 
the use of inorganic or polymeric thickening agents, and deliver improved 
cosmetics, product stability, and/or reduced solvent syneresis. These 
newer creams are typically anhydrous systems which have a penetration 
force value of from about 75 gram.multidot.force to about 500 
gram.multidot.force, a delta stress value of from about 300 dyne/cm.sup.2 
to about 8,000 dyne/cm.sup.2 as measured after extrusion of the 
composition through a shear force delivery means, and a static yield 
stress value of at least about 1,000 dyne/cm.sup.2 as measured after 
extrusion of the composition through a shear force delivery means. These 
newer creams are soft enough for application through a perforated dome but 
act as antiperspirant sticks in having minimal or no solvent syneresis 
during storage. When stress is applied to the new antiperspirant creams, 
preferably by extruding the cream through a perforated dome or other shear 
force delivery means, prior to application, the cream becomes more 
fluid-like and easier to apply topically to the skin. These newer creams 
are effective at maintaining product stability and minimizing solvent 
syneresis, especially when used in combination with higher concentrations 
of volatile solvents or lower viscosity nonvolatile solvents. 
It has been found, however, that although these newer antiperspirant creams 
are remarkably stable and have good spreadability, they are especially 
susceptible to solvent syneresis or product separation during and after 
application through a perforated dome or other shear force delivery means, 
sometimes resulting in weeping of solvent in and around the perforations 
of the perforated top during storage until the next application It is 
believed that the solvent syneresis results from residual pressure within 
the composition remaining after application from a packaged dispenser 
through a perforated dome. 
It has now been found that the solvent syneresis from the above-described 
creams and other similar compositions can be further minimize or 
eliminated by selecting a combination of package characteristics that help 
reduce or eliminate residual pressure, and thus reduce or eliminate 
solvent syneresis resulting from such residual pressures. 
It is therefore an object of the present invention to provide a packaged 
antiperspirant cream composition with improved stability and spreading 
performance. It is yet another object of the present invention to provide 
such a packaged composition wherein the packaged configuration containing 
the antiperspirant cream composition reduces or eliminates solvent 
syneresis during or after extrusion of the composition through the 
perforated dome. 
SUMMARY OF THE INVENTION 
The present invention is directed to packaged antiperspirant cream 
compositions, wherein the antiperspirant cream has a force penetration 
value of from about 75 gram.multidot.force to about 500 
gram.multidot.force and comprises from about 10% to about 80% by weight of 
a liquid carrier, from about 0.5% to about 35% by weight of an 
antiperspirant active; and from about 0.1% to about 40% by weight of a 
gellant. The antiperspirant cream is contained within a dispensing package 
having the following characteristics: 
i) a container body having an interior chamber of generally uniform or 
symmetrical cross section to contain the antiperspirant cream composition 
and a lengthwise extending axis, 
ii) an elevator having a cross section congruent to and mounted for axial 
movement within the interior chamber, 
iii) a perforated dome having a convex configuration and being attached to 
a dispensing end of the container body and having a plurality of openings 
extending through the thickness of the perforated dome; 
iv) a means for axially advancing the elevator toward the perforated dome; 
and 
v) optionally, a means for axially reciprocating the elevator away from the 
perforated dome; 
wherein the means for axially advancing the elevator and the optional means 
for axially reciprocating the elevator cooperate to reciprocate the 
elevator a minimum distance D.sub.min for each predetermined increment of 
forward axial advancement of the elevator by the means for axially 
advancing the elevator. 
The dispensing packages are selectively configured to minimize residual 
pressure on the packaged antiperspirant creams during and after extrusion, 
which then helps to minimize solvent syneresis. The present invention is 
directed to those compositions comprising select package configurations 
designed to minimize such residual pressures, such configurations include 
select 1) minimum retraction distances (Dmin values), 2) stiff or rigid 
container bodies such that under 3 psi of internal pressure the radius of 
a minor axis of a cross sectional area of the container body expands DO 
more than about 0.051cm, 3) convex perforated domes that substantially 
match the major and minor axis of the elevator or platorm above or on 
which the antiperspirant cream is positioned, 4) and other select 
configurations described hererin.

DETAILED DESCRIPTION OF THE INVENTION 
The packaged antiperspirant cream compositions of the present invention 
contain antiperspirant active dispersed or maintained in a suitable liquid 
carrier, preferably within a continuous water-insoluble or lipophilic 
phase. These antiperspirant cream compositions are contained within a 
dispensing package having a select configuration which is designed to 
reduce or eliminate solvent syneresis and product separation during and 
after extrusion of the product from the package. 
The term "anhydrous" as used herein means that the antiperspirant cream 
composition of the present invention, and the essential or optional 
components thereof, are preferably substantially free of added or free 
water. From a formulation standpoint, this means that the antiperspirant 
cream compositions of the present invention preferably contain less than 
about 2%, preferably less than about 1%, more preferably less than about 
0.5%, most preferably zero percent, by weight of free or added water. The 
preferred "anhydrous liquid carriers" described hereinafter likewise 
contain no more than the above-described percentages of free or added 
water. 
The terms "shear force delivery means" and "perforated dome" are used 
interchangeably herein and refer to the convex, perforated dome of the 
dispensing package herein, which perforated dome comprises a plurality of 
openings, apertures or orifices (hereinafter referred to collectively as 
apertures or openings) through which the antiperspirant cream compositions 
described herein are extruded, and that during such extrusion, the 
perforated dome subjects the composition to shear that is generally 
insufficient to substantially liquefy the composition, preferably a shear 
force less than the dynamic stress value of the composition, more 
preferably a shear force less than the static stress value of the 
composition. Examples of such perforated domes or shear force delivery 
means are described in greater detail hereinafter. 
The term "ambient conditions" as used herein refers to surrounding 
conditions under about one atmosphere of pressure, at about 50% relative 
humidity, at about 25.degree. C. 
The term "substantially free of polymeric or inorganic thickening agents" 
as used herein refers to preferred embodiments of the compositions of the 
present invention, and means that the compositions preferably contain less 
than an effective amount of such agents when used alone to provide any 
thickening or measurable viscosity increase to the composition. In this 
context, the polymeric and inorganic thickening agents refer only to 
materials that are solid under ambient conditions. Generally, the 
compositions preferably contain less than 5%, more preferably less than 
2%, more preferably less than 1%, even more preferably less than 0.5%, 
most preferably zero percent, of such thickening agents by weight of the 
composition. Examples of inorganic thickening agents to which the 
above-described negative but preferred limitations pertain include finely 
divided or colloidal silicas, fumed silicas, and silicates, which includes 
montmorillonite clays and hydrophobically treated montmorillonites, e.g., 
bentonites, hectorites and colloidal magnesium silicates. Examples of 
polymeric thickening agents to which the above-described negative but 
preferred limitations also pertain include polymers well known in the 
antiperspirant or personal care art for use in providing thickening 
benefits to a composition, specific examples of which include hydrogenated 
butylene/ethylene/styrene copolymer, polyethylene, acrylic acid polymers, 
ethylene acrylate copolymers, and other polymeric thickening agents 
described in Rheological Properties of Cosmetics and Toiletries, Edited by 
Dennis Laba, published by Marcel Dekker, In., New York (1993), which 
description is incorporated herein by reference. All such preferably 
excluded polymeric and inorganic thickening agents are solids under 
ambient conditions. 
The term "cross section" as used herein, unless otherwise specified, refers 
to a cross section of the container body as defined herein, wherein the 
cross section is perpendicular to the lengthwise extending axis of the 
container body. 
The packaged antiperspirant cream compositions of the present invention can 
comprise, consist of, or consist essentially of the essential elements and 
limitations of the invention described herein, as well as any of the 
additional or optional ingredients, components, or limitations described 
herein. 
All percentages, parts and ratios are by weight of the total composition, 
unless otherwise specified. All such weights as they pertain to listed 
ingredients are based on the active level and, therefore, do not include 
solvents or by-products that may be included in commercially available 
materials, unless otherwise specified. 
KAGED COMPOSITION 
The packaged antiperspirant cream composition of the present invention is a 
combination of the antiperspirant cream composition described herein and a 
package as defined herein for topically dispensing the antiperspirant 
cream composition to the underarm or other area of the skin. This 
combination results in improved spreading of the composition onto the 
skin, and reduces or eliminates solvent syneresis during and after 
application of the composition. 
The dispensing package of the compositions of the present invention 
comprises 1) a container body having an interior chamber of generally 
uniform or symmetrical cross section which contains the antiperspirant 
cream composition and has a lengthwise extending axis, 2) an elevator 
having a cross section congruent to and mounted for axial movement within 
the interior chamber, 3) a perforated dome fixed or attached to a 
dispensing end of the container body and having a plurality of openings 
extending through the thickness of the convex dome, 4) a means for axially 
advancing the elevator toward the perforated dome; and 5) optionally, a 
means for axially reciprocating the elevator away from the perforated dome 
wherein the means for axially advancing the elevator and the optional 
means for axially reciprocating the elevator may cooperate to reciprocate 
the elevator a minimum distance D.sub.min (cm) for each predetermined 
increment of forward axial advancement of the elevator by the means for 
axially advancing. The minimum reciprocating distance is determined by 
either of the expressions D.sub.min =[V.sub.max -V.sub.rest ]/A or 
D.sub.min =k.sub.v .multidot.(P.sub.y -Y.sub.s)/A, each expression being 
described in detail hereinafter. 
The container body of the dispensing package has at least one cross 
sectional area having a ratio of a major axis to a minor axis of from 
about 1:1 to about 5:1, preferably from about 1.5:1 to about 4:1, more 
preferably from about 1.7:1 to about 2.5:1. The internal surface area of 
the container body is from about 5 cm.sup.2 to about 30 cm.sup.2, 
preferably from about 5 cm.sup.2 to about 20 cm.sup.2, more preferably 
from about 10 cm.sup.2 to about 20 cm.sup.2, wherein the internal surface 
area is the surface area (cm2) of the interior of the package from the top 
of the elevator to the first edge of the first perforation in the 
perforated dome. 
The container body is preferably a rigid or stiff structure that does not 
readily expand during extrusion of the antiperspirant cream composition. 
Preferably, the container body is sufficiently stiff or rigid such that, 
under 3 psi (pounds per sq. inch) of internal pressure, the radius of a 
minor axis of a cross sectional area of the container body expands no more 
than about 0.051 cm, preferably less than 0.015 cm, more preferably less 
than about 0.010 cm, most preferably zero cm. It has been found that such 
rigid or stiff structures help to further minimize solvent syneresis 
during and after extrusion of the antiperspirant cream compositions 
herein. 
The perforated dome of the dispensing package is a convex surface, 
preferably a rigid surface, having a plurality of apertures extending 
through the thickness of the dome, and through which the antiperspirant 
cream composition is extruded and flows to the intended side of 
application on the skin. The perforated dome is attached or fixed to the 
dispensing end of the container body, and has a convex configuration that 
extends away or protrudes from the container body, and which has a major 
to minor axis ratio of a cross sectional area as described herein for the 
container body. 
The aperture in the perforated dome represent from about 15% to about 80%, 
preferably from about 30 % to about 60 %, more preferably from about 39% 
to about 50%, of the surface area of the perforated dome. In this context, 
the surface area of the perforated dome corresponds to the surface area as 
seen and measured from a topographical view of the perforated cap. The 
convex configuration of the perforated dome preferably has a radius of 
curvature of from about 25 mm to about 127 mm, more preferably from about 
57 mm to about 69 mm, for a major dimension; a radius of curvature of 
preferably from about 12 mm to about 39 mm, more preferably from about 22 
mm to about 28 mm for a minor dimension; average aperture area preferably 
from about 0. 12 cm.sup.2 to about 0.50 cm.sup.2, more preferably from 
about 0.2 cm.sup.2 to about 0.35 cm.sup.2, wherein the aperture areas can 
have a circular or noncircular configuration, preferably a circular 
configuration having an average circular diameter preferably from about 
1.9 mm to about 2.6 mm, more preferably from about 0.6 mm to about 26 mm; 
average interstitial spacing preferably from about 0.076 cm to about 0.419 
cm; a perforated dome thickness preferably from about 0.25 mm to about 
1.53 mm, more preferably from about 0.7 mm to about 0.97 mm; a dome major 
axis preferably from about 38 mm to about 77 mm, more preferably from 
about 52 mm to about 69 mm; and a dome minor axis preferably from about 12 
mm to about 51 mm, more preferably from about 18 mm to about 40 mm. 
The dispensing package also comprises a means for initially pressuring or 
axially advancing the antiperspirant cream composition within the 
container body toward the perforated dome to thus force a discrete amount 
of the antiperspirant cream composition to extrude through the plurality 
of apertures in the perforated dome and out of the container body. Such 
means are well known in the packaging and antiperspirant art, and include 
mechanisms such as feed screws or other similar functioning systems which 
drive or force an elevator or platform too impel the antiperspirant cream 
composition in a substantially unidirectional manner toward the perforated 
dome at the dispensing end of the package. The elevator or platform 
typically represents the bottom of the dispensing package on or above 
which the antiperspirant cream composition rests prior to dispensing. 
The elevator or platform within the dispensing package preferably has a 
rounded, convex configuration that substantially matches the rounded, 
convex configuration of the perforated dome at the dispensing end of the 
package. The elevator preferably has a minor axis of curvature within 
about 10.degree., preferably within about 2.degree., more preferably 
within about 1.degree., of the minor curvature axis of the perforated 
dome, and a major axis of curvature within about 10.degree., preferably 
within about 2.degree., more preferably within about 1.degree., of the 
major curvature axis of the perforated dome. It has been found that 
substantially matching these two surfaces helps to further reduce solvent 
syneresis during and after extrusion. 
The dispensing package also preferably comprises a means for retracting 
product from the perforated dome after extrusion, thus reducing or 
eliminating residual internal pressure. Such means preferably reduces 
residual internal pressure by at least about 80%, preferably by at least 
about 90%, preferably by 100%. 
Preferred pressure reduction means include reciprocatory mechanisms which 
retract the impelling elevator or platform a suitable minimum distance 
after advancing toward the perforated dome and dispensing the desired 
amount of the composition, thus preferably reducing residual internal 
pressure on the packaged composition to below the internal pressure 
threshold at which solvent syneresis occurs. Examples of dispensing 
packages comprising suitable mechanisms are described in U.S. Pat. No. 
5,000,356, issued to Johnson et al. on Mar. 19, 1991, and U.S. Pat. No. 
4,865,231, issued to Wiercinski on Sep. 12, 1989, which patents are 
incorporated herein by reference in their entirety. 
A key feature of the dispensing package herein is the extent of internal 
residual pressure reduction for any given combination of a dispensing 
package and an antiperspirant cream composition after each incremental and 
discrete extrusion of antiperspirant cream from the dispensing package. 
Pressure reduction can be accomplished by retracting the elevator or 
platform a select minimum retraction distance (D.sub.min) or a distance 
exceeding the minimum retraction distance, to reduce the internal residual 
pressure on the antiperspirant cream composition to below the pressure at 
which solvent syneresis occurs. 
The packaged antiperspirant cream compositions of the present invention 
have, therefore, a minimum retraction distance (D.sub.min) to help achieve 
the desired residual pressure relief, wherein the retraction distance must 
at be least about, but may also exceed, the Dmin value as defined herein. 
The minimum retraction distance (D.sub.min) as described above can be 
determined or otherwise characterized by either of two expressions, the 
first of which is represented by the following expression: 
EQU D.sub.min =(V.sub.max -V.sub.rest)/A 
wherein D.sub.min is the minimum retraction distance (cm), V.sub.max is the 
maximum volumetric deformation (cm.sup.3) of the container body during 
extrusion, V.sub.rest is the volumetric deformation (cm.sup.3) of the 
container body prior to extrusion, and "A" is a cross sectional area 
(cm.sup.2) of the container body. The maximum volumetric deformation 
V.sub.max is defined herein as the volumetric difference (cm.sup.3) 
between the volume of the container body during extrusion and the volume 
of the container body when empty prior to filing, whereas the term 
"V.sub.rest " as used herein refers to the volumetric difference 
(cm.sub.3), if any, between the filled and unfilled volume of the 
container body prior to any extrusion. Both volumetric values are easily 
measured or otherwise determined for any packaged system herein by the 
skilled artisan using conventional, routine or otherwise known measurement 
techniques. 
The minimum retraction distance (D.sub.min) can also be determined for any 
given packaged antiperspirant cream composition by the following 
expression: 
EQU D.sub.min =k.sub.v .multidot.(P.sub.y -Y.sub.s)/A 
wherein "A" is a cross sectional area (cm.sup.2) of the container body, 
k.sub.v is the volumetric compliance coefficient (cm.sup.3 /psi) of the 
dispensing package, P.sub.y is the product yield pressure (psi), and 
Y.sub.s is the static yield stress (psi)(defined hereinafter) of the 
composition. 
Methodology: Volumetric Coefficient 
The volumetric compliance coefficient (k.sub.v) can be determined by 
injecting a known amount of fluid into the dispensing package and then 
measuring the resulting internal pressure, all in accordance with the 
following methodology. 
Cast the bottom portion of the container body (elevator removed) of the 
dispensing package in a soft resin to seal it. The resin should seal the 
container body sufficiently to maintain the integrity of the container 
body during testing, but soft enough so as to not impact volumetric 
deformations of the container body during testing. Insert and seal a 
flexible membrane into the perforated dome to sufficiently seal the 
openings in the dome during testing. The flexible membrane should be 
sufficiently soft and flexible to not significantly affect the volumetric 
measurements of the container body during testing while also providing a 
seal sufficient to maintain the integrity of the container body during 
testing. Drill and tap the container body to accept a fluid connector and 
pressure transducer, and then connect the pressure transducer to the fluid 
connector. Connect a syringe to the container body by any method of 
attachment that does not introduce extra compliance to the system, i.e. do 
not use flexible hose. The syringe must be sized to approximate at least 
the maximum volumetric deformation of the container body during normal 
use. 
Fill the resulting scaled system with waiter (ambient temperature) so that 
there are no air bubbles within the system, and then inject water from the 
syringe into the container body in 0.1-1 cc increments and record the 
corresponding internal press resulting therefrom. The volumetric 
compliance coefficient k.sub.v can then be calculated as the inverse slope 
of the line defined by the recorded incremental pressure and corresponding 
injected fluid volumes. 
Methodology: Product Yield Pressure 
The product yield pressure is the pressure at which the product begins to 
flow and is a function of both the dispensing package characteristics and 
product rheology. The product yield pressure (Py) is measured using a 
dispensing packaging and a tension/compression tester such as an Instron 
8511 with a 50 lbf load cell. The dispensing package is placed on the load 
cell and the package elevator is advanced slowly (0.0635 cm/sec) and the 
force required to advance the elevator is recorded on suitable data 
acquisition equipment. The product yield pressure is the measured maximum 
steady state force required to advance the elevator divided by the 
dispensing package cross sectional area. 
It has been found that solvent syneresis or phase separation of the 
antiperspirant cream compositions while within the dispensing package can 
be minimized or eliminated when the antiperspirant cream composition is 
incorporated into the dispensing package defined herein. Such solvent 
syneresis or phase separation can occur as a result of residual pressure 
within the packaged composition after extrusion. This residual pressure 
can be minimized by reciprocating the advancing elevator away from the 
perforated dome after extrusion a minimum retraction distance 
(D.sub.min)as determined by either of the expressions described 
hereinabove. It has also been found that, in accordance with either of the 
expressions described hereinabove, solvent syneresis or product separation 
of the packaged composition is further minimized or eliminated by 
increasing the stiffness of the container body (thus decreasing the 
volumetric compliance coefficient), increasing the open area in the 
perforated dome (thus decreasing the product yield pressure), and/or by 
matching the convex configuration of the elevator to conform substantially 
with the configuration of the convex perforated dome. 
RHEOLOGY 
The antiperspirant cream compositions of the present invention are 
preferably anhydrous and preferably have a rheology profile that helps 
improve product stability and performance. The rheology profile as defined 
herein is a combination of product hardness (penetration force), delta 
stress (dyne/cm.sup.2) and static yield stress (dynelcm.sup.2) values for 
the antiperspirant cream compositions. Methods for measuring or 
determining each of these characteristics of the preferred rheology 
profile are described in detail hereinafter. Rheology methodologies are 
carried out at 27.degree. C., 15% relative humidity, unless otherwise 
specified. 
1. Methodology: delta stress and static yield stress 
To determine delta stress and static stress yield values for the preferred 
antiperspirant cream compositions of the present invention, the 
compositions are analyzed using a Rheometrics Dynamic Stress Rheometer 
(available from Rheometrics Inc., Piscataaany, N.J., U.S.A) with data 
collection and analysis performed using Rhios software 4.2.2 (also 
available from Rheometrics Inc., Piscatawany, N.J., U.S.A.). The rheometer 
is configured in a parallel plate design using a 25 mm upper plate 
(available as part number LS-PELT-IP25 from Rheometrics Inc., Piscatawany, 
N.J., U.S.A.). Temperature control is set at 37.degree. C. Analysis of the 
antiperspirant cream is performed in the "Stress Sweep: steady meep" 
default test mode. Rheometer settings are initial stress (1.0 
dyne/cm.sup.2), final stress (63,930 dynelcm.sup.2 ), stress increment 
(100 dyne/cm.sup.2 ), and maximum time per data point (5 seconds). 
The term "static yield stress" as used herein refers to the minimum amount 
of stress (dyne/cm.sup.2) that must be applied to the antiperspirant cream 
composition to move the upper plate of the Rheometrics Dynamic Stress 
Rheometer a distance of about 4.2 micro radians, in accordance with the 
analysis methods described herein. In other words, static yield stress 
represents the point in a stress sweep analysis (described herein) of a 
product at which point the rheometer is first capable of measuring product 
viscosity. 
The term "delta stress" as used herein is determined by subtracting the 
static yield stress from the dynamic yield stress of a composition. The 
dynamic yield stress is the point at which the measured viscosity begins 
to rapidly decline. This can be easily determined by finding the last 
stress value where the increment between stress values is 100 
dynes/cm.sup.2. In other words, the delta stress of the composition 
represents the incremental amount of stress that must be applied to the 
composition, beyond the static yield stress of the composition, to 
substantially liquefy the composition after extrusion. 
The preferred antiperspirant cream compositions of the present invention 
are first evaluated for rheology characteristics before extrusion (e.g., 
evaluation of a packaged product) through a defined perforated dome. A 28 
gauge metal wire is used to slice of a thin section (about 1 mm thick) 
from the packaged antiperspirant cream. During and after slicing, care is 
taken so that the product slice is subjected to minimal shear, and 
especially that it is not permitted to curl or otherwise reconfigure to a 
shape other than that of the section as it was removed from the packaged 
composition The section is carefully placed flat on the lower plate of the 
rheometer taking care to minimize the application of shear stress on the 
section during the placement. The area of the placed section is at least 
about the size of the upper plate to assure proper contact between the two 
plates during testing. The upper plate is then lowered toward the bottom 
plate, and positioned about 2 mm above the lower plate, and therefore 
about 1 mm from the product section which is positioned flat on the lower 
plate. The upper plate is further lowered at a mninimal rate toward the 
lower plate, and positioned about 1.000 (.+-.0.002) mm above the lower 
plate, at which point the product slice is gently positioned between and 
contacting each of the lower and upper plates. Excess product extending 
away from and around the parallel positioned plates is gently removed 
using a spatula, and taking care to subject the product positioned between 
plates to minimal or no further shear from the spatula The solvent guard 
pad on the rheometer is saturated with the type of liquid carrier 
corresponding to that in the test product. The solvent guard is lowered 
over the parallel plates to prevent solvent loss from the test product 
that is positioned between the plates during analysis. The product is now 
ready for rheology analysis and determination of dynamic stress, static 
yield stress, and delta stress. 
The preferred antiperspirant cam compositions are also evaluated for 
rheology characteristics immediately after the composition is extruded 
through a perforated dome. The perforated dome used in this analysis has 
the general configuration of the perforated dome shown in FIG. 2. To 
prepare product for such an evaluation, the product is first extruded 
through the perforated dome until from about 1 to about 3 mm of product 
extends from the exterior of the perforated dome. Gently remove extruded 
product from the surface of the dome using a spatula and place the removed 
product in the center of the lower plate, all along being careful to 
subject the product to minimal or no shear. Product should have an area at 
least about the size of the upper plate to assure proper contact between 
the two plate. The upper plate is lowered to about 2 mm, and then at a 
minimal rate further lowered to about 0.500 (.+-.0.002) mm. Excess product 
extending away from and around the parallel positioned plates is gently 
removed using a spatula, and again taking care to subject the product 
positioned between plates to minimal or no further shear from the spatula. 
The solvent guard is lowered over the parallel plates to prevent solvent 
loss during analysis. The solvent guard should be saturated with the 
selected liquid carrier corresponding to the type of carrier in the test 
product prior to placement of test product on the instrument. The extruded 
product thus positioned between the parallel plates is now ready for 
rheology analysis and determination of dynamic stress, static yield 
stress, and delta stress. 
Product samples before extrusion and product samples after extrusion 
through the perforated dome are subjected to rheological test and 
evaluation in accordance with the above described methodology. Data from 
the above described analysis can be plotted as viscosity 
(pascal.multidot.sec.) on a log scale versus linear applied stress 
(dyne/cm.sup.2), an example of which is shown in FIG. 1 herein. The 
initial point at which the instrument measures a viscosity is the static 
yield stress (i.e. the lowest stress at which the instrument shows a 
non-zero viscosity). The dynamic yield stress is the point at which the 
measured viscosity begins to rapidly decline. This can be easily 
determined by finding the last stress value where the increment between 
stress values is 100 dyne/cm.sup.2. The delta stress is then determined by 
subtracting the static yield stress from the dynamic yield stress. 
2. Methodology: product hardness 
The antiperspirant cream compositions of the present invention are 
evaluated for product hardness (gram.multidot.force) and defined in terms 
of force penetration values. The penetration force values are a reflection 
of how far a defined penetration cone will penetrate through an 
antiperspirant cream composition under the following test conditions. 
Higher values represent harder product, and lower values represent softer 
product These values are measured at 27.degree. C., 15% relative humidity, 
using a TA-XT2 Texture Analyzer, available from Texture Technology Corp, 
Scarsdale, N.J., U.S.A. The penetration force value as used herein 
represents the force required to move a standard 45.degree. angle 
penetration cone through the composition for a distance of 10 mm at a rate 
of 2 mm/second. The standard cone is available from Texture Technology 
Corp., as part number TA-15, and has a total cone length of about 24.7 mm, 
angled cone length of about 18.3 mm, a maximum diameter of the angled 
surface of the cone of about 15.5 mm. The cone is a smooth, stainless 
steel construction and weights about 17.8 grams. 
3. Rheology Profile 
The antiperspirant cream compositions preferably have a rheology profile as 
defined by three rheology characteristics--product hardness, static yield 
stress, and delta stress. As to the first rheology characteristic, the 
product hardness is characterized as a penetration force value of from 
about 75 gram force to about 500 gram.multidot.force, preferably from 
about 100 gram.multidot.force to about 400 gram force, more preferably 
from about 150 gram.multidot.force to about 250 gram force. 
The second preferred rheology characteristic of the antiperspirant cream 
compositions is a static yield stress value as measured after extrusion of 
the composition through a shear force delivery means, and preferably as 
also measured prior to such extrusion. The compositions have a static 
yield stress value as measured after extrusion of at least about 1,000 
dynelcm.sup.2, preferably at least about 3,000 dyne/cm.sup.2, even more 
preferably at least about 4,000 dyne/cm.sup.2, and most preferably at 
least about 10,000 dyne/cm.sup.2. The composition preferably also has a 
maximum static yield stress value as measured after extrusion of less than 
about 63,000 dyne/cm.sup.2, more preferably less than about 35,000 
dyne/cm.sup.2. 
The compositions also preferably have a static yield stress value prior to 
extrusion of at least about 4,000 dyne/cm.sup.2, more preferably at least 
about 8,000 dynelcm.sup.2, even more preferably at least about 40,000 
dyne/cm.sup.2. The maximum static yield stress values for the composition 
prior to extrusion are preferably less than about 120,000 dyne/cm.sup.2, 
more preferably less than about 63,000 dyne/cm.sup.2. 
Highly preferred are compositions having a static yield stress value as 
measured after extrusion of from about 4,000 dyne/cm.sup.2 to about 35,000 
dyne/cm.sup.2. Also highly preferred are compositions having a static 
yield stress as measured prior to extrusion of from bout 4,000 
dyne/cm.sup.2 to about 63,000 dyne/cm.sup.2. 
Products with a static yield stress value below the minimum levels recited 
herein can shear thin too much prior to application by the end user, or 
are otherwise physically unstable, especially during extended storage in a 
closed applicator package or during rough shipping to distributors or 
consumers. This product instability or excessive thinning of the product 
matrix can result in solvent syneresis from the composition during 
packaging, shipping or extended storage. 
The second preferred rheology characteristic of the antiperspirant cream 
compositions is a select range of delta stress values, wherein the delta 
stress values are measured either prior to or after extrusion through a 
shear force delivery means. The delta stress value of the composition is 
from about 300 dyne/cm2 to about 8,000 dyne/cm.sup.2, preferably from 
about 1,000 dyne/cm.sup.2 to about 6,000 dyne/cm.sup.2, more preferably 
from about 1,000 dyne/cm.sup.2 to about 5,000 dyne/cm.sup.2. A delta 
stress below the minimum level can result in solvent syneresis during 
extrusion through a perforated dome or other shear force delivery means, 
whereas a value above the recited maximum can result in product fracture 
during extrusion, nonuniform spreading onto the skin, and reduced 
spreadability on the skin, especially on hairy areas of the skin. 
Syneresis during extrusion of the composition through a perforated dome 
results in a separated, messy and excessively liquid composition being 
delivered topically to the skin. The delta stress values, therefore, 
recited herein provide for improved flow of the antiperspirant cream 
through a perforated dome or other shear force delivery means, and 
furthermore provides for a smooth creamy product after extrusion that 
shows minimal or no solvent syneresis, spreads uniformly over the skin, 
and spreads especially well over and through hairy areas of the skin. 
The compositions of the present invention are preferably characterized in 
terms of delta stress and yield stress values after extrusion of the 
composition, although the compositions can alternatively be characterized 
in terms of delta stress and yield stress values prior to such extrusion. 
The compositions can also be characterized in terms of delta stress and 
yield stress values before and after extrusion. 
For purposes of defining the preferred embodiments of the present 
invention, the delta stress and static yield stress characteristics for 
extruded compositions are measured in accordance with the rheology 
methodology described herein. Such methodology requires a shear force 
delivery means having the general perforated dome configuration as 
illustrated in FIG. 2, wherein the perforated dome has circular apertures 
in the illustrated configuration having diameters of 2.5, 2.4, and 1.9 mm; 
aperture spacing of from 0.76 to 1.8 mm; a dome major axis of 52.1 mm; a 
dome minor axis of 33.0 mm; a dome radius of curvature (major) of 57.1 mm; 
a dome radius curvature (minor) of 22.9 mm; and a dome thickness of from 
0.79 mm to 0.89 mm. 
It has been found that by controlling the preferred rheology profile of the 
antiperspirant cream composition to within the narrow ranges described 
herein, this provides a means for improving product stability, aesthetics, 
and performance in an antiperspirant cream composition without reliance on 
polymeric or inorganic thickening agents. 
ANTIPERSPIRANT ACTIVE 
The packaged antiperspirant cream compositions of the present invention 
comprise an antiperspirant active suitable for application to human skin. 
The antiperspirant active may be solubilized or in the form of particulate 
solids The antiperspirant active is preferably that which remains 
substantially unsolubilized as dispersed solid particulates in an 
anhydrous or substantially anhydrous system. The concentration of active 
in the composition should be sufficient to provide the desired odor and 
wetness control from the antiperspirant cream formulation selected. 
The antiperspirant cream compositions preferably comprise the 
antiperspirant active at concentrations of from about 0.5% to about 35%, 
more preferably from about 5% to about 30%, even more preferably from 
about 10% to about 26%, by weight of the unpackaged composition. These 
weight percentages are calculated on an anhydrous metal salt basis 
exclusive of water and any complexing agents such as glycine, glycine 
salts, or other complexing agents. The antiperspirant active is preferably 
in the form of dispersed solid particles having a preferred average 
particle size or diameter of from about 1 .mu.m to about 100 .mu.m, more 
preferably from about 1 .mu.m to about 50 .mu.m. 
The antiperspirant active for use in the packaged antiperspirant cream 
compositions include any compound, composition or other material having 
antiperspirant activity. Preferred antiperspirant actives include the 
astringent metallic salts, especially the inorganic and organic salts of 
aluminum, zirconium and zinc, as well as mixtures thereof. Particularly 
preferred are the aluminum and zirconium salts, such as aluminum halides, 
aluminum hydroxyhalides, zireonyl oxyhalides, zirconyl hydroxyhalides, and 
mixtures thereof. 
Preferred aluminum salts for use in the antiperspirant cream composition 
include those which conform to the formula: 
EQU Al.sub.2 (OH).sub.a Cl.sub.b .multidot.x H.sub.2 O 
wherein a is from about 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. Particularly preferred are the aluminum chlorhydroxides referred 
to as "5/6 basic chlorhydroxide", wherein a=5, and "2/3 basic 
chlorhydroxide", wherein a=4. Proceses for preparing aluminum salts are 
disclosed in U.S. Pat. No. 3,887,692, Gilman, issued Jun. 3, 1975; U.S. 
Pat. No. 3,904,741, Jones et al., issued Sep. 9, 1975; U.S. Pat. No. 
4,359,456, Gosling et al., issued Nov. 16, 1982; and British Patent 
Specification 2,048,229, Fitzgerald et al., published Dec. 10, 1980, all 
of which are incorporated herein by reference. Mixtures of aluminum salts 
are described in British Patent Specification 1,347,950, Shin et al., 
published Feb. 27, 1974, which description is also incorporated herein by 
reference. 
Preferred zirconium salts for use in the antiperspirant cream composition 
include those which conform to the formula: 
EQU ZrO(OH).sub.2-a Cl.sub.a .multidot.x H.sub.2 O 
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. These zirconium 
salts are described in Belgian Patent 825,146, Schmitz, issued Aug. 4, 
1975, which description is incorporated herein by reference. Particularly 
preferred zirconium salts are those complexes which additionally contain 
aluminum and glycine, commonly known as ZAG complexes. These ZAG complexes 
contain aluminum chlorhydroxide and zirconyl hydroxy chloride conforming 
to the above described formulas. Such ZAG complexes are described in U.S. 
Pat. No. 3,679,068, Luedders et al., issued Feb. 12, 1974; Great Britain 
Patent Application 2,144,992, Callaghan et al., published Mar. 20, 1985; 
and U.S. Pat. No. 4,120,948, Shelton, issued Oct. 17, 1978, all of which 
are incorporated herein by reference. 
The antiperspirant cream composition herein can also be formulated to 
comprise other dispersed solids or other materials in addition to or in 
place of the antiperspirant active. Such other dispersed solids or other 
materials include any material known or otherwise suitable for topical 
application to human skin. The antiperspirant cream composition can also 
be formulated as a cosmetic cream which contains no active materials, 
particulate or otherwise. 
GELLANT 
The packaged antiperspirant cream compositions of the present invention 
preferably comprise one or more gellants suitable for topical application 
to human skin. Preferred are those gellants that can form in the 
composition a crystalline or other gellant matrix within which a liquid 
carrier or other liquid component of the composition are contained. 
The concentration of the gellants in the composition may vary with each 
selected antiperspirant cream formulation, especially with each selected 
liquid carrier of the formulation, but such concentrations will generally 
range from about 0. 1% to about 40%, preferably from about 1% to about 
25%, more preferably from about 3% to about 20%, even more preferably from 
about 3% to about 12%, by weight of the unpackaged composition. 
Suitable gellants for use in the composition are typically solids under 
ambient conditions. These solid gellants preferably have a melting point 
of from 60.degree. C. to about 140.degree. C., preferably from about 
60.degree. C. to about 120.degree. C., more preferably from about 
70.degree. C. to about 110.degree. C. The solid gellant will typically and 
preferably be a crystalline material. Likewise, the gellant matrix in the 
composition will typically and preferably be a crystalline matrix. 
The gellants for use in the antiperspirant cream compositions are 
preferably those which can melt and form a homogenous liquid or homogenous 
liquid dispersion with the selected liquid carrier, and at the selected 
gellant and liquid carrier concentrations, at a processing temperature of 
from about 28.degree. C. to about 125.degree. C. The melted gellant is 
typically dispersed throughout the selected liquid carrier to thus form a 
homogenous liquid. The homogenous liquid, and other essential and optional 
ingredients, are preferably combined in accordance with the manufacturing 
method herein, placed in the select package configuration defined 
hereinbefore as a flowable homogenous liquid, and then allowed to solidify 
and form the desired gellant matrix within the composition as the 
temperature returns to ambient temperatures and drops to below the 
solidification point of the selected gellant 
In selecting a combination of gellant and liquid carrier for use in the 
antiperspirant cream compositions, the selected combination preferably 
allows for the development of a gellant matrix within the composition that 
will help deliver the preferred delta stress and static yield stress 
values described herein. The liquid carrier and gellant combination are 
also preferably selected so as to formulate a composition having the 
preferred product hardness, with minimal or no destruction of the gellant 
matrix as it develops within the antiperspirant cream composition during 
the making process. Maintaining the gellant matrix as it develops in the 
composition is important to obtaining the desired rheology profile defined 
herein, especially delta stress and static yield stress values. The liquid 
carrier and gellant combination are also preferably selected so as to 
assist in minimizing gellant crystal particle size within the 
antiperspirant cream composition. Methods for mninimizing gellant particle 
size in various compositions are known generally in the art, and the 
control of such particle size to help achieve the desired rheology 
characteristics is easily accomplished by one of ordinary skill in the art 
without undue experimentation. 
Gellants for use in the antiperspirant composition include fatty alcohols, 
esters of fatty alcohols, fatty acids, amides of fatty acids, esters or 
ethers of fatty acids including triglycerides, ethoxylated fatty alcohols, 
ethoxylated fatty acids, corresponding salts thereof, combinations 
thereof, and other crystalline gellants known or otherwise effective in 
providing the desired gellant matrix within the antiperspirant 
composition. All such gellants preferably have a fatty alkyl moiety having 
from about 14 to about 60 carbon atoms, more preferably from about 20 to 
about 40 carbon atoms, and which may be saturated or unsaturated, 
substituted or unsubstituted, branched or linear or cyclic. Preferred 
fatty alkyl moieties are saturated, more preferably saturated and 
unsubstituted 
The term "substituted" as used herein refers to chemical moieties known or 
otherwise effective for attachment to gellants or other compounds. Such 
substituents include those listed and described in C. Hansch and A. Leo, 
Substituent Constants for Correlation Analysis in Chemistry and Biology 
(1979), which listing and description are incorporated herein by 
reference. Examples of such substituents include, but are not limited to, 
alkyl, alkenyl, alkoxy, hydroxy, oxo, nitro, amino, aminoalkyl (e.g., 
aminomethyl, etc.), cyano, halo, carooxy, alkoxyaceyl (e.g., carboethoxy, 
etc.), thiol, aryl, cycloalkyl, heteroaryl, heterocycloalkyl (e.g., 
piperidinyl, morpholinyl, pyrrolidinyl, etc.), imino, thioxo, 
hydroxyalkyl, aryloxy, arylalkyl, and combinations thereof. 
The term "corresponding salts" as used herein refers to cationic salts 
formed at any acidic (e.g., carboxyl) group, or anionic salts formed at 
any basic (e.g., amino) group, either of which are suitable for topical 
application to human skin. Many such salts are known in the art, examples 
of which are described in World Patent Publication 87105297, Johnston et 
al., published Sep. 11, 1987, which description is incorporated herein by 
reference. 
Nonlimiting examples of suitable esters of fatty alcohols include 
tri-isostearyl citrate, ethyleneglycol di-12-hydroxystearate, 
tristearylcitrate, stearyl octanoate, stearyl heptanoate, 
trilaurylcitrate, and combinations thereof. 
Suitable fatty alcohols may be used in the composition at concentrations 
preferably ranging from about 0.1% to about 8%, more preferably from about 
3% to about 8%, even more preferably from about 3% to about 6%, by weight 
of the composition. The fatty alcohol gellants are also preferably 
saturated, unsubstituted, monohydric alcohols or combinations thereof, 
which have a melting point preferably less than about 110.degree. C. 
Specific examples of fatty alcohol gellants for use in the antiperspirant 
compositions that are commercially available include, but are not limited 
to, Unilin 550, Unilin 700, Unilin 425, Unilin 400, Unilin 350, and Unilin 
325, all supplied by Petrolite. 
Suitable ethoxylated gellants include, but are not limited, Unithox 325, 
Unithox 400, and Unithox 450, Unithox 480, Unithox 520, Unithox 550, 
Unithox 720, Unithox 750, all of which are available from Petrolite. 
Suitable fatty acid esters for use as gellants include ester waxes, 
monoglycerides, diglycerides, triglycerides and combinations thereof. 
Preferred are the glyceride esters. Nonlimiting examples of suitable ester 
waxes including stearyl stearate, stearyl behenate, palmityl stearate, 
stearyl octyldodecanol, cetyl esters, cetearyl behenate, behenyl bebenate, 
ethylene glycol distearate, ethylene glycol dipalmitate, beeswax, and 
combinations thereof. Examples of commercial ester waxes include Kester 
waxes from Koster Keunen, Crodamol SS from Croda and Demalcare SPS from 
Rhone Poulenc. 
Preferred are glyceryl tribehenate and other triglycerides, wherein at 
least about 75%, preferably about 100%, of the esterified fatty acid 
moieties of said other triglycerides each have from about 18 to about 36 
carbon atoms, and wherein the molar ratio of glyceryl tribehenate to said 
other triglycerides is from about 20:1 to about 1:1, preferably from about 
10:1 to about 3:1, more preferably from about 6:1 to about 4:1. The 
esterified fatty acid moieties may be saturated or unsaturated, 
substituted or unsubstituted, linear or branched, but are preferably 
linear, saturated, unsubstituted ester moieties derived from fatty acid 
materials having from about 18 to about 36 carbon atoms. The triglyceride 
gellant preferably has a preferred melting point of less than about 
110.degree. C. Preferred concentrations of the triglyceride gellants in 
the antiperspirant composition range from about 4% to about 20%, more 
preferably from about 4% to about 10%, by weight of the composition. 
Specific examples of preferred triglyceride gellants include, but are not 
limited to, tristearin, tribehenate, behenyl palmityl behenyl 
triglyceride, palmityl stearyl palmityl triglyceride, hydrogenated 
vegetable oil, hydrogenated rape seed oil, castor wax, fish oils, 
tripalmiten, Syncrowax HRC and Syncrowax HGLC (Syncrowax is available from 
Croda, Inc.). Other suitable glycerides include, but are not limited to, 
and glyceryl stearate and glyceryl distearate. 
Suitable amide gellants include monoamide gellants, diamide gellants, 
triamide gellants, and combinations thereof, nonlimiting examples of which 
include cocoamide MEA (monoethanolamide), stearamide, oleamide, oleamide 
MEA, tallow amid monoethanolamide, and the n-acyl amino acid amide 
derivatives described in U.S. Pat. No. 5,429,816, issued to Hofrichter et 
al. on Jul. 4, 1995, which description is incorporated herein by 
reference. 
Suitable fatty acid gellants include, but are not limited to, 
12-hydroxystearic acid and derivatives thereof, behenic acid, eurcic acid, 
stearic acid, C20 to C40 fatty acids, and related gellants, some preferred 
examples of which are disclosed in U.S. Pat. No. 5,429,816, issued to 
Hofrichter et al. on Jul. 4, 1995; and U.S. Pat. No. 5,552,136, issued to 
Motley on Sep. 3, 1996, both disclosures of which are incorporated by 
reference herein. Some commercial examples of fatty acid gellants include, 
but are not limited to, Unicid 400, available from Petrolite. 
Preferred crystalline gellants for use in the antiperspirant composition 
include coconut monoethanolamide, glyceryl tribehenate, C18-36 
triglyceride, hydrogenated rapeseed oil, C20 to C40 alcohols, C20 to C40 
pareth-3 and combinations thereof. Concentration of coconut 
monoethanolamide in the composition preferably ranges from about 5% to 
about 20%, more preferably from about 5% to about 15%, by weight of the 
composition. Coconut monoethanolamide is especially preferred when used in 
compositions containing a volatile silicone solvent, especially volatile 
cyclomethicone, and in compositions containing a combination a volatile 
silicone carrier and a nonvolatile silicone (e.g., nonvolatile 
dimethicones) or a nonvolatile organic carrier. 
Glyceryl tribehenate and hydrogenated rapeseed oil are also preferred 
gellants when used in gellant systems containing C20 to C40 fatty alcohols 
and/or C20 to C40 pareth-3, wherein the weight ratio of glyceryl 
tribehenate or hydrogenated rapeseed oil to C20 to C40 fatty alcohols 
and/or C20 to C40 pareth-3 is from about 20:1 to about 1:1, preferably 
from about 10:1 to about 3:1. These gellants are especially preferred when 
used in compositions containing volatile silicone carrier, especially 
volatile cyclomethicone, and in compositions containing a combination of a 
volatile silicone carrier and a nonvolatile silicone (e.g., nonvolatile 
dimethicones) or a nonvolatile organic carrier. 
Some of the gellants suitable for use in the antiperspirant cream 
composition herein are also described in U.S. Pat. No. 5,552,136, issued 
to Motley on Sep. 3, 1996; and U.S. Pat. No. 5,429,816 issued to 
Hofrichter et al. on Jul. 4, 1995; which descriptions are incorporated 
herein by reference. 
It has been found that the preferred gellants for use in the antiperspirant 
cream composition of the present invention are those which form a 
crystalline matrix within the composition, which in turn preferably 
provides the rheology profile (delta stress, static yield stress, 
penetration force) described herein. In particular, the preferred gellant 
should be combined with an appropriate liquid carrier and formulated into 
the composition so as to form crystallized gellant forming a crystalline 
matrix, wherein the size of the gellant crystals in the matrix are 
preferably minimized. It is also desirable that the formulation results in 
the development of a crystalline matrix within the composition with 
minimal or no application of any shear force that might otherwise break 
down the structure of the matrix. Preferred methods for preparing these 
more desirable crystalline matrices within the composition are described 
in detail hereinafter. 
The gellant material in the composition preferably has an average particle 
size within the matrix of less than about 10 .mu.m, more preferably from 
about 0.1 .mu.m to about 5 .mu.m, even more preferably from about 1 .mu.m 
to about 4 .mu.m. It has been found that these smaller crystalline 
particles are especially effective in developing the preferred rheology 
model of the composition described herein. These smaller particles form an 
improved crystalline matrix within which the dispersed particulate 
antiperspirant active is physically held in place over extended periods, 
and within which the liquid carrier component of the composition is held 
with minimal or reduced solvent syneresis during storage, transport and 
extrusion through a perforated dome. 
LIQUID CARRIER 
The packaged antiperspirant cream compositions of the present invention 
comprise a liquid carrier for the gellant as described herinbefore, 
wherein the liquid carrier is preferably anhydrous and comprises one or 
more liquid carriers each or collectively having a solubility parameter 
typically from about 3 to about 13, preferably from about 5 to about 11, 
more preferably from about 5 to about 9. The term "liquid carrier" and 
"carrier" are used interchangeably herein, and refer to the liquid carrier 
component of the composition, which preferably forms a homogenous liquid 
with the selected gellant during processing as described herein. 
Solubility parameters for selected liquid carrier or other materials, and 
means for determining such parameters, are well known in the 
antiperspirant art. A description of solubility parameters and means for 
determining them are described by C. D. Vaughan, "Solubility Effects in 
Product, Package, Penetration and Preservation" 103 Cosmetics and 
Toiletries 47-69, October 1988; and C. D. Vaughan, "Using Solubility 
Parameters in Cosmetics Formulation", 36 J Soc. Cosmetic Chemists 319-333, 
September/October, 198, which descriptions are incorporated herein by 
reference. 
Concentrations of the liquid carrier in the composition will vary with the 
type of liquid carrier selected, the type of gellant used in combination 
with the liquid carrier, the solubility of the selected gellant in the 
selected carrier, and so forth. Preferred concentrations of the liquid 
carrier ranges from about 10% to about 80%, preferably from about 20% to 
about 70%, more preferably from about 45% to about 70%, by weight of the 
composition. 
The liquid carrier comprises one or more liquid carriers suitable for 
topical application to human skin, which carrier or combination of liquid 
carriers are liquid under ambient conditions. These liquid carriers may be 
organic or silicone-containing, volatile or nonvolatile, polar or 
nonpolar, and preferably provide form a homogenous liquid or homogenous 
liquid dispersion with the selected gellant at the selected gellant 
concentration at a temperature of from about 28.degree. C. to about 
125.degree. C. The liquid carrier preferably has a low viscosity to 
provide for improved spreading performance on the skin, more preferably 
less than about 50 cs (centistokes), even more preferably less than about 
10 cs. The liquid carrier is preferably anhydrous. 
The liquid carrier preferably comprises one or more volatile carriers, 
optionally in combination with a nonvolatile carrier. In this context, the 
term "volatile" refers to criers having a measurable vapor pressure under 
ambient conditions, and the term "nonvolatile" refers to carriers which do 
not have a measurable vapor pressure under ambient conditions. 
Preferred volatile liquid carriers are the volatile silicone carriers, 
which includes cyclic, linear or branched chain volatile silicones. 
Nonlimiting examples of suitable volatile silicones are described in Todd 
et al., "Volatile Silicone Fluids for Cosmetics", Cosmetics and 
Toiletries, 91:27-32 (1976), which descriptions are incorporated herein by 
reference. Preferred volatile silicone materials are those having from 
about 3 to about 7, more preferably from about 4 to about 5, silicon 
atoms. Cyclic silicones are preferred. 
Suitable cyclic silicones for use in the antiperspirant cream composition 
include those volatile silicones which conform to the formula: 
##STR1## 
wherein n is from about 3 to about 7, preferably from about 4 to about 5, 
most preferably 5. These cyclic silicone materials will generally have 
viscosity values of less than about 10 cs at .degree. C. 
Suitable linear silicones suitable for use in the antiperspirant cream 
compositions include those volatile linear silicones which conform to the 
formula: 
##STR2## 
wherein n is from about 1 to about 7, preferably from about 2 to about 3. 
These linear silicone materials will generally have viscosity values of 
less than about 5 cs at 25.degree. C. 
Specific examples of volatile silicone carriers suitable for use in the 
antiperspirant compositions include, but are not limited to, 
Cyclomethicone D-5 (commercially available from G. E. Silicones), Dow 
Corning 344, Dow Corning 345 and Dow Corning 200 (commercially available 
it from Dow Corning Corp.), GE 7207 and 7158 (commercially available from 
General Electric Co.) and SWS-03314 (commercially available from SWS 
Silicones Corp.). 
Other suitable carriers for use in the composition include nonvolatile 
silicone emollients, preferably low viscosity nonvolatile silicone 
carriers having a viscosity of less than about 500 cs, more preferably 
from about 5 cs to about 50 cs, more preferably from about 5 cs to about 
20 cs. These silicone emollients include, but are not limited to, 
polyalkylsiloxanes, polyaryarylsiloxanes and polyethersiloxane copolymers. 
Examples of such emollients are well known in the art, some of which are 
described in 1 Cosmetics, Science and Technology 27-104 (M. Balsam and E. 
Sagarin ed. 1972); U.S. Pat. No. 4,202,879, issued to Shelton on May 13, 
1980; and U.S. Pat. No. 5,069,897, issued to Orr on Dec. 3, 1991; which 
descriptions are incorporated herein by reference. 
Organic carriers for use in the composition include saturated or 
unsaturated, substituted or unsubstituted, branched or linear or cyclic, 
organic compounds that are also liquid under ambient conditions. These 
carriers include hydrocarbon oils, alcohols, organic esters and ethers 
that are liquid under ambient conditions. Preferred organic carriers 
include mineral oil and other hydrocarbon oils, some examples of which are 
described in U.S. Pat. No. 5,019,375, issued to Tanner et al. on May 28, 
1991, which description is incorporated herein by reference. Other 
suitable organic liquid carriers include Permethyl 99A, Permethyl 101A 
(Permethyl available from Permethyl Corp.), Isopar M, Isopar V (Isopar 
available from Exxon) , isohexadecane, disopropyl adipate, butyl stearate, 
isododecane, light mineral oil, petrolatum and other similar materials. 
Highly preferred are liquid carriers comprising a combination of volatile 
and nonvolatile silicone carriers, especially when such combinations are 
also anhydrous. Examples of such preferred combinations are described in 
U.S. Pat. No. 5,156,834 (Beckmeyer et al.), which descriptions are 
incorporated herein by reference. 
OPTIONAL COMPONENTS 
The packaged antiperspirant cream compositions of the present invention may 
further comprise one or more optional components which may modify the 
physical or chemical characteristics of the compositions or serve as 
additional "active" components when deposited on the skin. The 
compositions may also further comprise optional inert ingredients. Many 
such optional materials are known in the antiperspirant art and may be 
used in the packaged antiperspirant compositions herein, provided that 
such optional materials are compatible with the essential materials 
described herein, or do not otherwise unduly impair product performance. 
Non limiting examples of optional materials include active components such 
as bacteriostats and fungiostats, and "non-active" components such as 
colorants, perfumes, emulsifiers, chelants, distributing agents, 
preservatives, residue masking agents, and wash-off aids. Examples of such 
optional materials are described in U.S. Pat. No. 4,049,792, Elsnau, 
issued Sep. 20, 1977; Canadian Patent 1,164,347, Beckmeyer et at., issued 
Mar. 27, 1984; U.S. Pat. No. 5,019,375, Tanner et al., issued May 28, 
1991; and U.S. Pat. No. 5,429,816, Hofrichter et al., issued Jul. 4, 1995; 
which descriptions are incorporated herein by reference. 
METHOD OF MANUFACTURE 
The packaged antiperspirant cream compositions of the present invention may 
be prepared by any known or otherwise effective technique for formulating 
such compositions, and are preferably formulated by any known or otherwise 
effective technique which results in an antiperspirant cream composition 
having the preferred rheology characteristics described hereinbefore,. 
Application of shear is preferably not applied to the product after its 
point of solidification. Such methods preferably involve formulation of 
the essential components of the composition to form a soft cream having 
the preferred hardness, static yield stress, and delta stress described 
herein, wherein the gel or crystalline matrix within the soft cream 
preferably comprises gellant crystals having am average particle diameter 
that is minimized through methods well known in the formulation art for 
minimizing crystalline particle size in a composition. 
The point of solidification in the manufacturing method herein corresponds 
to the point at which the composition becomes turbid due to gellant 
crystallization in the absence of other dispersed solids in the 
composition, or when the apparent viscosity increases during the 
solidification process step described herein. In this context, the term 
"apparent viscosity" means that the viscosity of the composition appears 
by visual inspection during the solidification step to have increased. 
The manufacturing methods preferably result in the formation of crystalline 
gellant particles having an average particles diameter of less than about 
10 .mu.m, more preferably from about 0.1 .mu.m to about 5 .mu.m, even more 
preferably from about 1 .mu.m to about 4 .mu.m. Crystalline particle 
morphology includes platelets, spheres, needles, and so forth. In this 
context, the average particle diameter refers to the average particle 
diameter at about the narrowest section of the crystalline particle. 
Crystalline particle size in the preferred embodiments of the present 
invention can be determined by techniques well known in the art, which 
includes light microscopy of the composition, wherein the composition is 
formulated for analysis purposes without antiperspirant active or other 
solid particulates. Without such reformulation, it is more difficult to 
distinguish crystalline gellant particle size from particle size 
contributed from other nongellant particulates. The reformulated 
composition is then evaluated by light microscopy or other similar method. 
Methods for preparing the antiperspirant cream compositions of the present 
invention include those methods well known in the art for formulating 
compositions containing small gellant crystalline particles. Such methods 
include the use of nucleating agents, formulation with select carriers or 
gellants or carrier/gellant combinations, controlling rates of 
crystallization including controlling formulation and processing 
temperatures, and so forth. All such methods should be applied to the 
formulation to control or minimize gellant crystal particle size to form 
the desired crystalline matrix of the composition and the desired rheology 
characteristics arising therefrom. 
A preferred method for preparing such a composition comprises a formulation 
step followed by a controlled solidification step. The formulation step 
involves preparing a flowable liquid comprising 1) from about 5% to about 
35% by weight of a particulate antiperspirant active, from about 0.1% to 
about 20% by weight of a crystalline gellant, and from about 10% to about 
80% of an anhydrous liquid carrier for the crystalline gellant, the 
anhydrous liquid carrier having a solubility parameter of from about 3 to 
about 13, preferably a volatile silicone carrier. The process preferably 
involves thorough mixing together of all of the essential and optional 
components at the desired temperature while adding minimal amounts of heat 
or other energy to liquefy and thoroughly mix all of the added 
ingredients. Processing temperatures will generally range from about 
28.degree. C. to about 125.degree. C., more preferably from about 
35.degree. C. to about 100.degree. C., even more preferably from about 
50.degree. C. to about 90.degree. C, but will vary with the melt profile 
of the ingredients in the mixture. In this context, the term "liquefy" 
means that the substantially all of the gellant and carrier material in 
the composition are melted or arm otherwise in the form of a combined 
flowable liquid, which combined flowable liquid comprises particulate 
antiperspirant active substantially uniformly dispersed therethrough. 
The second essential step in the preferred method of the making the 
compositions involves solidification of the liquefied mixture described 
hereinabove. The solidification preferably involves removal of the 
composition from any added heat or other energy source, and/or by 
subjecting the liquefied composition to active cooling. It is desirable 
that once the solidification process begins, that the liquefied 
composition is allowed to solidify to the requisite hardness with mninimal 
or no addition of substantial amounts of shear force, preferably without 
the addition of any additional shear force. It has been found that the 
addition of such additional shear force during the solidification step 
results in a crystalline network that is insufficient to maintain the 
preferred rheology profile described herein. Such additional shear force 
can break down the desired crystalline network if applied after the point 
of solidification, and it is the presence of such a structure crystalline 
network that is largely responsible for the rheology profile described 
herein, and the product performance and stability benefits resulting 
therefrom. 
The preferred method may further comprise the addition of optional 
materials. Such addition is preferably during the formulation step, 
wherein the essential and optional ingredients are mixed together to form 
a liquefied admixture. In making the compositions of the present 
invention, care must be taken to assure that the particulate 
antiperspirant materials are dispersed relatively uniformly throughout the 
composition. 
METHOD OF USE 
The packaged antiperspirant cream compositions of the present invention may 
then be applied topically to the skin after application from the packaged 
system defined herein. This method preferably involves application of an 
effective amount of the antiperspirant cream composition to the underarm 
or other area of the skin, preferably from about 0.1 gram to about 20 
grams, more preferably from about 0.1 gram to about 10 grams, even more 
preferably from about 0.1 gram to about 1 gram, of the composition to the 
desired area of the skin. The applied cream is rubbed over the applied 
surface one or more times during application using the packaged system 
defined herein until there is little or no visible residue on the applied 
surface. 
These application methods are preferably applied to the desired areas, 
typically to the underarm or other area of the skin, one to two times 
daily, preferably once daily, to achieve effective antiperspirant and odor 
control over an extended period. 
It has been found that this method of applying shear stress to the 
composition of the present invention is especially effective in providing 
even spreading of the composition to the skin, while providing a 
liquefying shear stress to the composition. The composition quickly shears 
after extrusion but during topical application to the skin to a creamy 
liquid that spreads smoothly and uniformly over the skin, and especially 
over the skin and through underarm hair. The improved spreading results in 
improved deodorant and antiperspirant efficacy. 
EXAMPLES 
The following nonlimiting examples illustrate specific embodiments of the 
packaged antiperspirant cream compositions of the present invention, 
including methods of manufacture and use. 
Each of the exemplified compositions are prepared by combining all of the 
listed components and heating the combination to 100.degree. C. with 
agitation to form a hot liquid. The heated liquid is allowed to cool with 
agitation until before the point of solidification, at which point the 
cooled, liquid composition is filled into select dispensing packages as 
defined herein and allowed to cool without further agitation or other 
applied shear to form a stiff cream within the corresponding dispensing 
package. 
TABLE 1 
__________________________________________________________________________ 
Example 
Example 
Example 
Example 
Example 
Component 1 5 
__________________________________________________________________________ 
Cyclomethicone D5.sup.1 
64.0 34.5 68.5 62.25 
67.25 
Al Zr trichlorohydrex glycinate.sup.2 
26.0 
26.0 
26.0 
26 
26 
Butyl stearate 34.5 5.0 
-- 
5.0 
-- 
C20-C40 alcohols.sup.3 
4.5 4.5 
5.0 
Glyceryl tribehenate 
-- -- 
-- 
5.0 
5.0 
C18-C36 triglyceride 
-- -- 
-- 
1.25 
1.25 
combination.sup.4 
Perfume 0.5 0.5 
0.5 
0.5 
0.5 
Rheology 
1. Hardness (gm force) 
170 150 200 170 200 
2. Delta stress (dyne/cm2) 
a) before extrusion 
3,800 
5,300 
6,800 
6,100 
4,200 
b) after extrusion 
3,00000 
7,500 
7,200 
3,300 
3. Static yield stress (dyne/cm2) 
a) before extrusion 
16,000 
4,300 
2,200 
11,800 
30,600 
b) after extrusion 
3,000,200 
1,600 
2,600 
23,000 
__________________________________________________________________________ 
.sup.1 Cyclic polydimethylsiloxane containing 5 carbons, supplied by G.E. 
Silicones 
.sup.2 Supplied by Westwood Chemical Corporation 
.sup.3 Unilin 425 from Petrolite 
.sup.4 Syncrowax HGLC from Croda 
TABLE 2 
__________________________________________________________________________ 
Example 
Example 
Example 
Example 
Example 
Example 
Component 12 
__________________________________________________________________________ 
Cyclomethicone.sup.5 
34.0 62.75 
62.75 
-- -- 62.75 
Dimethicone.sup.6 
5.0 
69.0 
5.0 
Glyceryl tribehenate 
5.0 
5.0 
C18-36 triglyceride 
1.25 
-- 
-- 
combination.sup.4 
C20-40 alcohols.sup.3 
1.25-- 
1.25 
-- 
-- 
Hydrogenated rapeseed oil.sup.7 
-- -- 
-- 
C20-40 Pareth-3.sup.8 
-- 
1.25 
Diisopropyl adipate 
62.75 
-- 
-- 
Butyl stearate -- 30.0 
-- 
-- 
Cocamide MEA.sup.9 
-- 10.0 
-- 
-- 
Perfume 
Al Zr tri chlorohydrex 
26.0 
26.0 
26.0 
26.0 
26.0 
glycinate.sup.2 
Rheology 
1. Hardness (gm force) 
218 88 84 117 362 143 
2. Static yield stress (dyne/cm2) 
a) before extrusion 
12,700 
5,300 
8,300 
19,550 
10,200 
27,200 
b) after extrusion 
5,60000 
9,700 
10,300 
10,150 
33,000 
3. Delta stress (dyne/cm2) 
a) before extrusion 
3,800 
5,500 
4,200 
5,700 
6,920 
7,100 
b) after extrusion 
4,300 
2,000 
3,800 
5,200 
6,433 
__________________________________________________________________________ 
.sup.5 Dow Corning 245 Fluid 
.sup.6 Dow Coming 200 Fluid 10 Cst viscosity 
.sup.7 High Eurcic Acid Hydrogenated Rapeseed Oil from Calgene 
.sup.8 Unithox 420 from Petrolite 
.sup.9 Coconut monoethanolamide from Mona 
.sup.10 Supplied by Westwood Chemical Corporation 
Each of the exemplified compositions 1-12 are then separately packaged in 
dispensing packages as defined herein, and which are further described as 
dispensing packages 1.1 and 1.2 in Table 3. Each of the dispensing 
packages have rigid container bodies (radius of the minor axis expands 
less than about 0.01 cm under 3 psi of internal pressure) and provide a 
D.sub.min value also as defined herein. Each of the dispensing packages 
also has a convex perforated dome and a convex elevator wherein the major 
curvature axis of the elevator is within about 1.degree. of the major 
curvature axis of the perforated dome, and the minor curvature axis of the 
elevator is within about 1.degree. of the minor curvature axis of the 
perforated dome. 
TABLE 3 
__________________________________________________________________________ 
Elevator 
Perforated 
Cont. body 
Package 
Container body major 
Container body 
advancement 
dome % open 
Internal surface 
No. axis (cm) minor axis (cm) 
(cm) area area (cm.sup.2) 
__________________________________________________________________________ 
1.1 6.323 2.858 0.035 42.9 15.054 
1.2 5.182 38.5 
9.75 
__________________________________________________________________________ 
Each of the packaged systems remain physically stable over extended periods 
of time, exhibit minimal or no solvent syneresis during or immediately 
extrusion through a perforated dome. The exemplified compositions are also 
especially effective in spreading uniformly over the skin, especially over 
hairy areas of the skin, to provide improved antiperspirant and deodorant 
efficacy.