Abstrict This invention provides cosmetic deodorant stick, roll-on and cream
formulations. An invention deodorant product comprises an organic
matrix having a dispersed solids phase which includes discrete crystallites
of bicarbonate salt ingredient and particulate boron oxide desiccant
ingredient. When an invention deodorant product is applied to a
skin surface, the boron oxide reacts with moisture, and converts
to boric acid which neutralizes any content of a strong basic irritant
such as alkali metal carbonate which is present as an impurity in
an alkali metal bicarbonate salt.
Claims What is claimed is:
1. A cosmetic deodorant product comprising an organic matrix which
contains a homogeneously dispersed particulate phase which comprises
(1) between about 0.5-20 weight percent of discrete crystallites
of at least one ingredient selected from alkali metal and ammonium
bicarbonates, and (2) between about 0.01-5 weight percent of particulate
boron oxide desiccant ingredient, based on product weight.
2. A cosmetic deodorant product in accordance with claim 1 which
is a cosmetic stick, roll-on or cream formulation.
3. A cosmetic deodorant product in accordance with claim 1 in which
the homogeneously dispersed particulate phase contains between about
0.01-3 weight percent of discrete crystallites of boric acid ingredient,
based on product weight.
4. A cosmetic deodorant product in accordance with claim 1 in which
the homogeneously dispersed particulate phase additionally contains
between about 0.1-15 weight percent of discrete crystallites of
antiperspirant ingredient, based on product weight.
5. A cosmetic deodorant product in accordance with claim 1 wherein
the homogeneously dispersed particulate phase has an average particle
size between about 1-200 microns.
6. A cosmetic deodorant product in accordance with claim 1 wherein
the crystallites of bicarbonate ingredient are in the form of organic-encapsulated
particles.
7. A cosmetic stick product consisting of a solid organic matrix
comprising the following parts by weight of ingredients:
and the solid organic matrix contains a homogeneously dispersed
particulate phase which comprises (1) between about 0.5-20 weight
percent of discrete crystallites of at least one ingredient selected
from alkali metal and ammonium bicarbonates, and (2) between about
0.01-5 weight percent of particulate boron oxide desiccant ingredient,
based on product weight.
8. A cosmetic stick product in accordance with claim 7 wherein
the volatile oil ingredient comprises a cyclic or linear polydimethylsiloxane
containing 3-9 silicon atoms.
9. A cosmetic stick product in accordance with claim 7 wherein
the volatile oil ingredient comprises a C.sub.12 -C.sub.20 branched-chain
hydrocarbon.
10. A cosmetic stick product in accordance with claim 7 wherein
the liquid emollient ingredient is a water-insoluble organic ester
or ether compound.
11. A cosmetic stick product in accordance with claim 7 wherein
the wax ingredient is selected from C.sub.8 -C.sub.30 alcohol, ester
and amide compounds.
12. A cosmetic stick product in accordance with claim 7 wherein
the bicarbonate crystallites are sodium, potassium or ammonium bicarbonate
or any mixture thereof.
13. A cosmetic stick product in accordance with claim 7 in which
the homogeneously dispersed particulate phase containing between
about 0.01-3 weight percent of discrete crystallites of boric acid
ingredient, based on product weight.
14. A cosmetic stick product in accordance with claim 7 in which
the homogeneously dispersed particulate phase additionally contains
between about 0.1-20 weight percent of discrete crystallites of
antiperspirant ingredient, based on product weight.
15. A cosmetic stick product in accordance with claim 7 wherein
the homogeneously dispersed particulate phase has an average particle
size between about 1-200 microns.
16. A cosmetic stick product in accordance with claim 7 wherein
the crystallites of bicarbonate ingredient are ill the form of organic-encapsulated
particles, and wherein the encapsulating polymer is a hydrophilic
polymer or a water-insoluble polymer or a mixture thereof, and the
polymer comprises between about 5-70 weight percent of the dry particle
weight.
17. A cosmetic roll-on product consisting of a liquid organic matrix
comprising the following parts by weight of ingredients:
and the liquid organic matrix contains a homogeneously dispersed
particulate phase which comprises (1) between about 0.5-20 weight
percent of discrete crystallites of at least one ingredient selected
from alkali metal and ammonium bicarbonates, and (2) between about
0.01-5 weight percent of particulate boron oxide desiccant ingredient,
based on product weight.
18. A cosmetic roll-on product in accordance with claim 17 wherein
the volatile oil ingredient comprises a cyclic or linear polydimethylsiloxane
containing 3-9 silicon atoms.
19. A cosmetic roll-on product in accordance with claim 17 wherein
the volatile oil ingredient comprises a C.sub.12 -C.sub.20 branched-chain
hydrocarbon.
20. A cosmetic roll-on product in accordance with claim 17 wherein
the liquid emollient ingredient is a water-insoluble organic ester
or ether compound.
21. A cosmetic roll-on product in accordance with claim 17 wherein
the wax ingredient is selected from C.sub.8 -C.sub.30 alcohol, ester
and amide compounds.
22. A cosmetic roll-on product in accordance with claim 17 wherein
the bicarbonate crystallites are sodium, potassium or ammonium bicarbonate
or any mixture thereof.
23. A cosmetic roll-on product in accordance with claim 17 in which
the homogeneously dispersed particulate phase contains between about
0.01-3 weight percent of discrete crystallites of boric acid ingredient,
based on product weight.
24. A cosmetic roll-on product in accordance with claim 17 in which
the homogeneously dispersed particulate phase additionally contains
between about 0.1-20 weight percent of discrete crystallites of
antiperspirant ingredient, based on product weight.
25. A cosmetic roll-on product in accordance with claim 17 wherein
the homogeneously dispersed particulate phase has an average particle
size between about 1-200 microns.
26. A cosmetic roll-on product in accordance with claim 17 wherein
the crystallites of bicarbonate ingredient are in the form of organic-encapsulated
particles, and wherein the encapsulating polymer is a hydrophilic
polymer or a water-insoluble polymer or a mixture thereof, and the
polymer comprises between about 5-70 weight percent of the dry particle
weight.
27. A method of practicing personal hygiene which comprises applying
a claim 1 cosmetic deodorant product to skin surfaces in a deodorant-effective
amount.
28. A method in accordance with claim 27 wherein the deodorant
product: is a cosmetic stick. roll-on or cream formulation.
Description BACKGROUND OF THE INVENTION
Antiperspirants combat axillary odors by inhibiting perspiration
through the action of astringent salts such as aluminum and zinc
salts, but may be irritating to a large number of users. Deodorants
function by neutralizing the objectionable odors resulting from
the degradation of several components of perspiration by chemical
and microbial action into malodorous fatty acids.
Numerous solid antiperspirant and/or deodorant compositions have
been described in the chemical and cosmetic literature. These compositions
generally are emulsion sticks or suspensoid sticks. Emulsion sticks
contain a solution of the antiperspirant ingredient incorporated
into the stick via an emulsion. Although emulsion sticks are desirable
in certain respects, they tend to be unstable, exhibit tackiness,
and leave a visible residue on the skin after use. Suspensoid sticks
contain the powdered antiperspirant ingredient suspended in the
stick without the use of water or an emulsion. While suspensoids
have stability, they tend to leave a white chalky residue on the
skin after application.
Manufacturers have found that anhydrous antiperspirant stick systems
are more marketable and have good consumer acceptance primarily
due to the ease of application to the skin, good cosmetic esthetics
and an acceptable degree of effectiveness. Previous to the development
of anhydrous stick systems, numerous water based systems were developed
in which the active astringent salts were solubilized in a thickened
or gelled composition. This is exemplified in U.S. Pat. Nos. 2732327;
2857315; 3255082; and 3928557. The water based systems are
difficult to apply to the skin, and their consistency and effectiveness
are variable.
Many anhydrous stick compositions have been described in the literature
which attempt to improve the delivery and the effectiveness of their
antiperspirant and deodorant characteristics. Antiperspirant stick
systems consisting of low molecular weight monohydric alcohols in
conjunction with polyhydric alcohols are described in U.S. Pat.
No. 4137306. These sticks have the advantage of quicker drying
rates, but the residue of the polyhydric alcohols in combination
with the astringent salts produces a high degree of tack, and their
effectiveness is limited to the type and amount of astringent salts
that could be incorporated in the stick matrix.
Anhydrous stick compositions that suspend the aluminum salt in
a hydrophobic matrix are described in U.S. Pat. No. 4049792. These
compositions employ waxy materials and long chain fatty esters to
form a stick that delivers the active astringent salts to the skin.
Cosmetic stick compositions made in accordance with these embodiments
are greasy, and the active astringent salt is enveloped in a manner
that prevents maximum performance. To alleviate this inherent negative
characteristic, volatile silicone fluids replacement of the less
volatile long chain fatty esters is described in U.S. Pat. No. 4126679.
This disclosure teaches the advantage of utilizing a volatile non-staining
liquid such as cyclic dimethylpolysiloxanes (referred to as volatile
silicones), in combination with various types of waxes, as a carrier
for the active astringent salts in an antiperspirant stick composition.
Similar antiperspirant stick compositions containing volatile silicones
are described in U.S. Pat. Nos. 4511554; 4980156; and 4985238.
With respect to deodorant activity, sodium bicarbonate has long
been recognized for its deodorant properties, and has commonly been
used as a household deodorant. Plain powdered sodium bicarbonate,
or sodium bicarbonate diluted with talc or other filler, has been
used as an underarm deodorant as disclosed in U.S. Pat. No. 4382079.
Other publications which describe cosmetic stick compositions containing
a bicarbonate deodorant include U.S. Pat. No. 4822602 and U.S.
Pat. No. 4832945.
However, the development of a practical and effective antiperspirant
composition in cosmetic stick form which is also capable of deodorization,
and which is capable of consumer acceptability, presents many factors
which are unique. Because sodium and potassium bicarbonate have
only limited solubility in water, alcohol and other solvents, the
preparation of a composition suitable for dispensing in cosmetic
stick form has involved many processing obstacles. In addition to
the problem of limited solubility, sodium bicarbonate often is incompatible
with the active astringent salts and with other ingredients of conventional
stick compositions. Also, the dimensional stability of the cosmetic
stick containing sodium bicarbonate, and the esthetic appearance
and the "feel" on the skin, are just a few of the additional
difficulties encountered in the preparation of a low residue cosmetic
deodorant or antiperspirant-deodorant product.
Another significant problem associated with the incorporation of
a bicarbonate deodorant ingredient in a cosmetic stick roll-on or
cream formulation is the tendency for the high density bicarbonate
salt particles to settle in the fluid medium during processing.
Also, under the elevated temperature conditions required for the
admixing and blending of ingredients, bicarbonate degradation and
evolution of carbon dioxide occur.
There is continuing interest in the development of improved cosmetic
products which exhibit deodorant activity, or antiperspirant-deodorant
activity.
Accordingly, it is an object of this invention to provide a cosmetic
stick roll-on or cream product which exhibits deodorant properties,
and is characterized by excellent esthetics and cosmetic properties.
It is another object of this invention to provide a homogeneous
cosmetic deodorant product which contains a dispersed phase of particulate
deodorant and desiccant ingredients in an organic matrix phase.
It is another object of this invention to provide a homogeneous
deodorant product which contains a dispersed particle phase of polymer-encapsulated
bicarbonate salt crystallites, and which is dimensionally stable.
Other objects and advantages of the present invention shall become
apparent from the accompanying description and examples.
DESCRIPTION OF THE INVENTION
One or more objects of the present invention are accomplished by
the provision of a cosmetic deodorant product comprising an organic
matrix which contains a homogeneously dispersed particulate phase
which comprises (1) between about 0.5-20 weight percent of discrete
crystallites of at least one ingredient selected from alkali metal
and ammonium bicarbonates, and (2) between about 0.01-5 weight percent
of particulate boron oxide desiccant ingredient, based on product
weight.
A present invention cosmetic deodorant product normally is in the
form of a cosmetic stick, roll-on or cream formulation.
The bicarbonate salt crystallites can have an average particle
size between about 1-200 microns. The boron oxide crystallites can
have an average particle size between 0.1-200 microns. A preferred
range for both bicarbonate and boron oxide crystallites is an average
particle size between about 1-80 microns.
The term "discrete" as employed herein refers to crystallites
which are individually distinct solids.
The term "average particle size" as employed herein refers
to the average of the largest dimension of the particles.
The particulate bicarbonate salt starting material of an invention
powder composition is selected from alkali metal and ammonium bicarbonates,
such as sodium bicarbonate, potassium bicarbonate and ammonium bicarbonate,
and mixtures thereof.
The boron oxide ingredient also is referred to as boron anhydride
(B.sub.2 O.sub.3) in the chemical literature. Boron oxide exists
in both crystalline and glass forms. Boron oxide solids can be ground
into an ultrafine powder.
Impurities present in boron oxide include metaboric acid (HBO.sub.2)
and boric acid (H.sub.3 BO.sub.3). Reagent grade boron oxide can
have a purity of 99.999%.
The boron oxide ingredient functions as a potent desiccant when
an invention cosmetic deodorant product has been formulated. It
readily absorbs trace amounts of moisture and maintains a cosmetic
deodorant product in an anhydrous state. When an invention cosmetic
product is applied to human skin such as underarm areas, the boron
oxide absorbs moisture exuded by the skin. The boron oxide keeps
the skin comfortably dry, as the boron oxide is converting to boric
acid via metaboric acid.
The transient boric acid byproduct has a soothing effect on the
applied skin area. The boric acid functions as a neutralizing agent
with respect to any strong basic irritant such as alkali metal carbonate
when it is an impurity in the alkali metal bicarbonate ingredient.
Boric acid is a weak and exclusively monobasic acid that is not
a proton donor, but acts as a Lewis acid by accepting hydroxyl anions
(OH.sup.-):
Boric acid can react with a strong base such as sodium carbonate.
Boric acid does not react with a weak base such as sodium bicarbonate,
but is susceptible to complex formation with the bicarbonate salt
under the conditions prevalent when a present invention cosmetic
product is applied to underarm skin areas to obtain a deodorizing
effect during daily personal hygiene usage.
A present invention cosmetic deodorant product can be formulated
originally with a homogeneously dispersed particulate phase which
can contain between about 0.01-3 weight percent of discrete crystallites
of boric acid ingredient, based on product weight. The boric acid
can be in addition to the boron oxide ingredient, or can be a substitute
therefor.
Commercial grade alkali metal bicarbonate bulk commodities typically
have a content of alkali metal carbonate, which is a residual byproduct
of the manufacturing process. Substantially all of the commercial
grade alkali metal bicarbonate is produced by carbonation of an
aqueous solution of alkali metal carbonate:
A residual quantity (e.g., 0.05-2 weight percent) of alkali metal
carbonate is adsorbed as a contaminant on the surfaces of the crystalline
alkali metal bicarbonate particles.
The presence of alkali metal carbonate in bulk alkali metal bicarbonate
powder is attributable also to an additional factor. Alkali metal
bicarbonate decomposes to alkali metal carbonate at elevated temperatures
above about 100.degree. C. At ambient temperatures, alkali metal
bicarbonate converts to alkali metal carbonate at a constant slow
rate. Typically, the initial residual alkali metal carbonate content
is less than about one weight percent of the bulk alkali metal bicarbonate
powder.
A reaction occurs between alkali metal carbonate impurity and boric
acid during the time period that a present invention cosmetic deodorant
product is on a skin surface after application.
The byproduct borates are anhydrous when initially formed, and
provide an extended drying effect by absorbing skin surface moisture.
In another embodiment the alkali metal bicarbonate ingredient can
comprise crystallites which are in the form of organic-encapsulated
particles. During a coating procedure, crystallites with a transient
liquid surface coating can make contact and coalesce into larger
encapsulated particles with a content of multiple crystallites.
The application of the organic coating to the alkali metal bicarbonate
ingredient crystallite surfaces is accomplished by conventional
means such as pan coating, fluidized coating, centrifugal fluidized
coating, and the like. The organic coating phase usually is dissolved
in a suitable solvent such as water, methanol, ethanol, acetone,
tetrahydrofuran, ethyl acetate, dimethylformamide, and the like,
as appropriate for a selected organic species. A coating phase also
can be applied in the form of an emulsion or suspension. After the
coating medium is applied to the crystallites, the solvent medium
is removed by evaporation, thereby forming a continuous film coating
which encapsulates the discrete fine grain crystallites.
In a preferred coating procedure, bicarbonate powder is dispersed
in an aqueous medium which contains a coating polymer ingredient.
The aqueous dispersion is atomized and sprayed into heated air to
remove the aqueous phase, and to provide a free-flowing polymer-encapsulated
bicarbonate powder product.
The coating thickness on the alkali metal bicarbonate crystallite
surfaces typically will vary in the range between about 0.1-20 microns.
The coating can consist of a single layer or multiple layers. The
organic coating can constitute between about 5-70 weight percent
of the total dry weight of the coated crystallites.
A polymer employed for coating the bicarbonate crystallites is
selected from hydrophilic organic polymers and hydrophobic (water-insoluble)
organic polymers and mixtures thereof.
A hydrophilic polymer employed for coating the bicarbonate crystallites
is selected from water-soluble and water-dispersible organic polymers.
A mixture of polymers can be employed, and a content of between
about 0.5-40 weight percent of a water-insoluble polymer, based
on the coating weight, can be included with a hydrophilic polymer.
The term "hydrophilic" as employed herein refers to an
organic species which has a water-solubility of at least about one
gram per 100 grams of water at 25.degree. C. The term "hydrophobic"
or "water-insoluble" as employed herein refers to an organic
species which has a water solubility of less than about one gram
per 100 grams of water at 25.degree. C.
Suitable hydrophilic compounds and polymers for coating ingredient
crystallites include gum arabic, gum karaya, gum tragacanth, guar
gum, locust bean gum, xanthan gum, carrageenan, alginate salt, casein,
dextran, pectin, agar, sorbitol, 2-hydroxyethyl starch, 2-aminoethyl
starch, maltodextrin, amylodextrin, 2-hydroxyethyl cellulose, methyl
cellulose, carboxymethyl cellulose salt, cellulose sulfate salt,
polyvinylpyrrolidone, polyethylene glycol, polypropylene glycol,
polyethylene oxide, polyvinyl alcohol/acetate, polyacrylamide, and
the like. Polyvinyl acetate is illustrative of a water-insoluble
polymer which can be included as an additional coating component
to moderate the hydrophilicity of a hydrophilic polymer coating.
Suitable water-insoluble polymers, alone or in combination with
one or more other components, for coating ingredient crystallites
include polyvinyl acetate, polyacrylamide, polyvinyl chloride, polystyrene,
polyethylene, polyurethane, and the like.
The rate of release of core matrix bicarbonate salt content of
the particles under moisture conditions can be controlled by the
quantity and type of organic coating on the particle surfaces.
Low molecular weight hydrophilic polymers will release the particle
core matrix content at a relatively fast rate in the presence of
moisture. High molecular weight polymers which are less hydrophilic
will release at a relatively slow rate. Additional rate control
can be obtained by employing mixtures of polymer components of varied
hydrophilicity.
Polyethylene glycol (M.W. of 4000) or polyvinyl alcohol will release
the particle core matrix content at a relatively fast rate. Polyethylene
oxide (M.W. of 4000000) or partially hydrolyzed polyvinyl acetate
will release at a relatively slow rate. Polyvinylpyrrolidone will
release the particle core matrix content at an intermediate rate
when in contact with underarm type of moisture.
In another embodiment this invention provides a cosmetic stick
product consisting of a solid organic matrix comprising the following
parts by weight of ingredients:
______________________________________ volatile oil 10-55 liquid
emollient 1-35 low melting point wax 12-30 ______________________________________
and the solid organic matrix contains a homogeneously dispersed
particulate phase which comprises (1) between about 0.5-20 weight
percent of discrete crystallites of at least one ingredient selected
from alkali metal and ammonium bicarbonates, and (2) between about
0.01-5 weight percent of particulate boron oxide desiccant ingredient,
based on product weight.
In another embodiment this invention provides a cosmetic roll-on
product consisting of a liquid matrix comprising the following parts
by weight of ingredients:
______________________________________ volatile oil 55-70 liquid
emollient 3-10 ______________________________________
and the liquid organic matrix contains a homogeneously dispersed
particulate phase which comprises (1) between about 0.5-20 weight
percent of discrete crystallites of at least one ingredient selected
from alkali metal and ammonium bicarbonates, and (2) between about
0.01-5 weight percent of particulate boron oxide desiccant ingredient,
based on product weight.
A present invention cosmetic stick, roll-on or cream deodorant
product can contain between about 0.1-20 weight percent of an antiperspirant
compound as an additional ingredient.
An invention antiperspirant-deodorant cosmetic stick product typically
contains the following weight proportions of main ingredients:
______________________________________ Ingredient Weight ______________________________________
volatile oil 25-50 liquid emollient 2-20 wax (MP 95.degree.-180.degree.
F.) 15-20 antiperspirant 20-28 encapsulated bicarbonate/ 0.1-25
fragrance powder surfactant 1-3 ______________________________________
The volatile oil ingredient preferably is selected from silicone
and branched-chain hydrocarbon compounds.
A volatile silicone oil ingredient in a cosmetic stick or roll-on
product of the present invention preferably is a cyclic or linear
polydimethylsiloxane containing between about 3-9 silicon atoms.
A suitable cyclic volatile polydimethylsiloxane compound is illustrated
by the formula: ##STR1## where n is an integer with a value of about
3-7.
A suitable linear polydimethylsiloxane is illustrated by the formula:
where n is an integer with a value of about 1-7.
Linear volatile silicone compounds generally have viscosities of
less than about 5 centistokes at 25.degree. C., while the cyclic
type compounds have viscosities of less than about 10 centistokes.
Typical of the volatile silicone compounds that can be employed
for purposes of the present invention is cyclomethicone, which is
a cyclic dimethylpolysiloxane conforming to the above formula where
n averages between 3-6. Dow Corning 245 Fluid (Dow Corning) is a
cyclic volatile silicone which is commercially available. CTFA Cosmetic
Ingredient Dictionary, Third Edition, (Estrin et al., Editors; The
Cosmetic, Toiletry and Fragrance Association, Inc.; 1982) lists
cyclic silicones on page 60 under the entry "Cyclomethicone".
A volatile hydrocarbon oil type of ingredient preferably is a C.sub.12
-C.sub.20 branched-chain hydrocarbon compound or mixture. Suitable
volatile branched-chain hydrocarbon oils include isododecane (C.sub.12),
isohexadecane (C.sub.16), isoeicosane (C.sub.20), and the like.
These types of branched-chain hydrocarbons are marketed by Permethyl
Corporation under tradenames such as Permethyl 99A, Permethyl 101A
and Permethyl 102A.
The liquid emollient ingredient of an invention cosmetic stick,
roll-on or cream deodorant product is selected from one or more
water-insoluble organic compounds which are liquid at 25.degree.
C. and which contribute a combination of properties that are advantageous
in an invention cosmetic stick or roll-on product.
The term "water-insoluble" as employed herein refers
to an emollient ingredient which has a water-solubility of less
than about one weight percent at 25.degree. C.
A present invention emollient ingredient exhibits a low degree
of irritation and toxicity in topical applications, and provides
a softening or soothing effect on surface skin tissue.
Preferred water-insoluble liquid emollients include fatty alcohols
such as oleyl, lauryl and hexadecyl; esters such as diisopropyl
adipate, benzoic acid esters of C.sub.9 -C.sub.15 alcohols, and
isononyl isononanoate; alkanes such as mineral oil; silicones such
as dimethylpolysiloxane and cyclic dimethylpolysiloxane; and ethers
such as polyoxypropylene butyl ether and polyoxypropylene cetyl
ether. Preferred water-insoluble liquid emollients include diisopropyl
adipate, 2-ethylhexyl palmitate, dimethylpolysiloxane (50 cst.),
and polyoxypropylene (14) butyl ether.
The low melting point wax ingredient of a present invention cosmetic
deodorant product comprises one or more organic compounds which
have a melting point in the range between about 95.degree.-180.degree.
F.
Suitable types of wax-like compounds include fatty alcohols, fatty
acid esters, fatty acid amides, and the like, which have an aliphatic
chain length between about 8-30 carbon atoms. Illustrative of wax-like
compounds are cetyl alcohol, myristyl alcohol, stearyl alcohol,
paraffin, and the like, and mixtures thereof.
The low melting point wax ingredient can include up to about 30
weight percent, based on the weight of wax ingredient, of a wax
which has a melting point between about 180.degree.-220.degree.
F. Illustrative of these higher melting waxes are beeswax, spermaceti,
carnauba, bayberry, candelilla,, montan, ozokerite, ceresin, paraffin,
castor wax, Fischer-Tropsch waxes, and the like.
The antiperspirant ingredient of a present invention cosmetic stick,
roll-on or cream antiperspirant deodorant product typically is a
particulate astringent compound which has an average particle size
between about 1-100 microns. Superior cosmetic stick properties
are obtained if part or all of the antiperspirant ingredient is
in the form of particles which have a diameter less than about one
micron. Optionally, the antiperspirant ingredient can be pre-coated
with a polymer to prevent interaction with the other ingredients,
and to provide a sustained-release antiperspirant activity under
application conditions.
Suitable astringent compounds include aluminum chloride, aluminum
chlorohydrate, aluminum sulfocarbolate, aluminum sulfate, aluminum-zirconium
chlorohydrate, zinc sulfate, zinc sulfocarbolate, and zirconium
chlorohydrate. Preferred types of astringent compounds are aluminum
chlorohydrates and aluminum-zirconium chlorohydrates, such as aluminum-zirconium
tetrachlorohydrex glycine. Aluminum-zirconium tetrachlorohydrex
glycine is commercially available as Rezal 36 GP Superultrafine
(Reheis), and Reach AZP 908 (Reheis).
Other optional ingredients also may be included in an invention
cosmetic formulation, such as bacteriostats, fungistats, fillers,
stabilizing agents, surfactants, antioxidants, pigments, coloring
agents, perfumes, chelating agents, and the like.
A surfactant ingredient of an invention cosmetic formulation is
selected from nonionic, cationic and anionic polymers. Suitable
surfactant polymers include cetyltrimethylammonium bromide; sodium
lauryl sulfate; sodium dodecylbenzene-sulfonate; ammonium lignosulfonate;
condensation products of ethylene oxide with fatty alcohols, amines
or alkylphenols; partial esters of fatty acids and hexitol anhydrides;
polyalkylene glycol esters; and the like. Illustrative of a preferred
type of surfactant polymer is polyethylene glycol (PEG) stearate,
which is commercially available as PEG 600 distearate.
A bacteriostat such as 244'-trichloro-2'-hydroxydiphenyl ether
(Triclosan) typically is added in a quantity between about 0.08-3
weight percent, based on the weight of the cosmetic stick, roll-on
or cream deodorant product.
In another embodiment this invention provides a method of practicing
personal hygiene which comprises applying a present invention cosmetic
stick, roll-on or cream deodorant product to skin surfaces in a
deodorant-effective amount, wherein the initiation and continuation
of deodorizing activity is signaled by a perceived dryness and esthetic
soothing effect.
Other advantages are provided by the practice of the present invention.
As noted in the Background section of the specification, the relative
densities of the organic matrix and suspension phases in a cosmetic
stick, roll-on or cream product directly affects the stability and
esthetics of the formulations.
Density matching of inorganic and organic phases is a significant
factor in cosmetic deodorant products. When a present invention
formulation contains an optional organic-coated bicarbonate deodorant
ingredient, it has a lower density which more closely matches the
density of the organic matrix of a cosmetic stick, roll-on or cream
product than does uncoated bicarbonate ingredient.
When there is density matching of organic matrix and dispersed
organic-coated bicarbonate particle phases, a cosmetic stick, roll-on
or cream product has improved dimensional stability, and better
esthetic appearance and "feel" when applied to human skin.
In general, the ingredients of a cosmetic deodorant formulation
can be blended in any order. However, in the practice of a process
for manufacture of a present invention cosmetic product there is
advantage in utilizing a phased order of ingredient addition and
blending under controlled temperature conditions. Additional advantage
is obtained in the process if there is a minimal time lapse between
the alkali metal bicarbonate deodorant ingredient addition step
and the cosmetic product container filling and solidifying step.
Alkali metal bicarbonate can convert to alkali metal carbonate,
carbon dioxide and water at elevated temperatures.
Adding the bicarbonate salt as the last ingredient of the blended
formulation, and processing the formulation to the final solid,
semi-solid or liquid cosmetic product formation stage within a short
time period, are factors which minimize the degradation of the bicarbonate
salt ingredient, and the undesirable formation of water and carbon
dioxide vapor byproducts. The addition and mixing of the bicarbonate
salt ingredient into the formulation, and the dispensing of the
formulation into cosmetic containers, can be accomplished as an
essentially instantaneous procedure by utilizing an integrated mixing
valve nozzle device, such as the type described in U.S. Pat. Nos.
2816518; 3454198; 3949904; 4318429; 4549813; 5046538;
5094276; and the like.
The practice of a process for the production of a cosmetic deodorant
product can be conducted in conventional equipment, and is readily
adaptable to a commercial-scale manufacturing operation.
A present invention cosmetic stick product preferably has a hardness
penetration value between about 4-12 millimeters, as determined
by American Society For Testing Materials (ASTM) Method D5.
A present invention cosmetic deodorant stick, roll-on or cream
product has exceptional properties for treating or preventing perspiration
and malodor associated with human underarm perspiration. A present
invention cosmetic deodorant formulation can be applied effectively
with safety and comfort for reduction of underarm perspiration and
offensive odors. |