Note: Descriptions are shown in the official language in which they were submitted.
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ANTIPERSPIRANT COMPOSITION AND PROCESS
This invention relates to nonaqueous su6pension type
antiperspirant compositions~ More particularly i~ relates to
compositions of this type that are particularly suitable for being
dispensed from the so called roll-on applicators.
For a long time the standard antiperspirant compositions that
were dispensed from roll-on applicators took the form of aqueou~
composition that had the consistency of a lotion. These products,
however, were found to be objectionable because of the "wet" and
"tacky`' fee~ that was experienced when they ~ere applied.
To overcome, this objection there ~as developed in the art,
essentially anhydrous su~pension antiperspirant products which could
be applied from a roll-on dispenser which went on dry and avoided
the "wet" and "tacky" feel noted abo~e. These prod~cts were
generally antiperspirant for~ulations in which po~dered anti-
perspirant materials were suspended in an essentially nonaqueousTM TM
~ilicone vehicle, by ~eans of Bentone 38 or Cab-O-Sil M5 as the
suspending agent. The~e compo~itions are illustrated in U.K. Patent
Application GB 2,018,590 published Oct. 24, 1979.
Although these products were improvements over the aqueous
compositions they left much to be desired from a stability point of
view. For example commercial antiperspirant, suspension roll-on
compositions containing Bentone 38 or Cab-O-Sil M5 shows upper layer
~eparation (about 20%) when stored overnight. It was therefore
necessary to shake the container significantly each time ~efore use.
It has now been found that the stability of the aforesaid
anhydrous antiperspirant suspension products may be i~proved if there
is used, as a suspending agent, a hydrophobic pyrogenic silica whose
surface structure on the exposed portions of the silica is largely
composed of hydrocarbon groups and is prepared by reacting conven-
tional pyrogenic silica with an organosilane such as halo alkyl
silanes (e.g. dimethyl dichloro-silan~) under conditions which
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cause a chemical reaction to occur with a substantial
portion of the hydroxyl groups on the surface of the
pyrogenic silica.
An aspect of the invention is as follows:
A nonaqueous liquid antiperspirant suspension
composition comprising by weight o~ the composition (a)
from about 30 to about 85% of a nonaqueous carrier, (b)
a dry, particulate active antiperspirant material
suspended in said nonaqueous carrier, said
antiperspirant material being present in said
composition at a concentration sufficient to act
effectively as an antiperspirant, and (c) from about 3
to about 8~ of a suspending agent from said
antiperspirant material which agent is a hydrophobic,
pyrogenic silica, the surface structure of said silica
having exposed portions, the major portion of which is
co~prised of hydrocarbon groups, said composition being
a flowable admixture of the constituents.
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Pyrogenic silicas of the a~oresaid type have been
used in a number of applications in the antiperspirant
art but not for the purpose for which it is prssently
employed. Thus Belgian Patent 895,610 shows the use of
this type of pyrogenic silica as an emulsifying agent in
emulsifying an aqueous solution of antiperspirant
materials in an oil. International Patent Application
Wo 80/02293 teaches the preparation of a dry
antiperspirant product which is converted to a cream
when it is subjected to shearing action. This is
prepared by high intensity mixing of an aqueous solution
of antiperspirant with the pyrogenic silica.
The pyrogenic silicas employed in the present
invention are distinguished from the generally
conventional pyrogenic silica (e.g. Cab-0-Sil) by its
mode of preparation which gives it its particular
hydrophobic character. These hydrophobic products are
prepared by reacting the conventional pyrogenic silica
with an organosilane such as halo alkyl silanes (e.g.
dimethyl dichlorosilane) under conditions which cause a
chemical reaction to occur with a substantial portion of
the hydroxyl groups on the surface of the pyrogenic
silica. This gives a new surface structure on the outer
or exposed portions of the silica which is largely
composed of hydrocarbon groups.
The preparation of hydrophobic silicas that are
useful for the purposes of the present invention are
described in U.S. Patent 3,393,155 col. 2, line 25 to
col. 3, line 18 and in the Example, col. 3, line 70 to
col. 4, line 6.
As pointed out therein, the pyrogenic silicas that
may be employed in preparing the hydrophobic silicas
that can be used herein are those having a surface area
of at least about 100 sq. meters per gram and mean
equivalent particle diameters of less than 50
millimicrons per gram. In order to provide a
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sufficiently hydrophobic surface on said silicas for
the purpose of this invention, it is merely necessary to
attach thereto in suitable concentration chemical
complexes bearing hydrocarbon or similar organo groups.
The molar concentration of such complexes required per
unit of surface area will depend somewhat on the number
and size of the organo groups therein. However, for the
organo silane complexes of primary interest, which carry
from 1 to 3 organo groups mostly of smaller size (e.g.
usually not over 7 carbon atoms per group), the
concentrations of the attached chemical complexes should
be in the range of about 0.2 millimoles or more per 100
sq. meters of surface area of the silica. For the
preferred silicas having BET surface areas of at least
about 150 sq. meters per gram, the carbon content after
surface treatment to provide a suitable hydrophobic
character will usually be about 1% by weight or more.
A number of hydrophobic silicas sold commercially
are employable in the present invention. These include
"Aerosol R 972--~M or "Silica R 972"TM (Degussa Inc.),
"Tullanox 500"TM (Tl~lco Inc.), "Silanox"TM (Cabot
Corp.), Cab O-Sil N 70-TSTM etc. A material of choice
is Silica R 972 currently marketed by Degussa Inc.
In preparing the compositions of this invention the
antiperspirant material will be suspended in the
nonaqueous liquid vehicle using as the suspending agent
the pyrogenic silica defined above. The quantity of
pyrogenic silica that will be employed for this purpose
will vary with the quantity of vehicle and
antiperspirant employed, the character of the product
desired, etc. Generally, however, this will constitute
from about 3% to about 8~ by weight based on the total
weight of the composition, the preferred range being
from about 4% to about 7% on the same weight basis.
A variety of anhydrous liquid vehicles may be
utilized in manufacturing the present products. These
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will usually be volatile oily organic liquids many of
which are known in this art as being useful in preparing
suspension type antiperspirant products. By way of
example mention may be made of Cyclomethicones and
mixtures thereo~. In the pre~erred form of this
invention the nonaqueous vehicle will be constituted
primarily by one or more volatile silicones ti.e. one or
more Cyclomethicones).
A number of volatile silicones are available on the
market which may be employed for the present purposes.
These include such materials as Volatile Silicone 7158
(Union Carbide), Siloxane F-222 ~SWS SILICONES), Dow
Corning Q2-1201 Fluid, ~ilicone Fluid SF-1202 (General
Electric), Volatile Silicone 7207 (Union Carbide),
Siloxane Q3314 (SWS Silicones), Dow Corning X2-1145
Fluid, Silicone Fluid SF-1173 (General Electric) etc.
Additional examples of Cyclomethicones that may be
employed are given in the CTFA Cosmetic Ingredient
Dictionary, Third edition, 1982 (published by the
Cosmetic, Toiletry and Fragrance Association, Inc.,
Washington, D.C.) at p. 600 One or more of the
aforesaid Cyclomethicones may be used alone or in
combination with each other.
Cyclomethicone is a cyclic dimethyl polysiloxane.
This conforms to the formula
C~
~ r ~ ~ Q ~1
L c~3 - 1~ 1
I
where n has an average value of between 3 and 6.
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The quantity of anhydrous volatile liquid carrier
used in the compositions of this invention may vary
somewhat. Generally, this will constitute between about
30% to about 85% by weight based on ~he total weight o-f
the composition with preferred range being from about
40~ to about 75% on the same weight hases.
It is a feature of the compositions of this
invention that the active antiperspirant material is
suspended in the nonaqueous vehicle employed herein.
This material is employed in a dry particulate form as
for example as powders, granules, crystals etc. that is
intimately distributed in the vehicle. The particle
sizes of these materials can vary widely but usually
they will be in the range o~ from about 5 micron to 70
micron is size.
Any of the variety antiperspirant materials well
known to those skilled in thus art may be used for the
present purposes. These include such materials as
aluminum chlorohydrate, aluminum sesquichlorohydrate,
and Al/Zr polychlorohydrate glycine or their
combinations. The aluminum zirconium polychlorohydrate
complexes that may be incorporat~d in the composition of
the present invention may be described by the general
formula:
5a
~r
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~ 32;~
(I) AlxZr(OH)yClz . nCH2COOH . mH20
wherein:
(a) x is a number from 2 to 10;
(b) z is a number from 3 to 8;
(c) y equals (3x +4) - z;
Id) the sum of y + z is a numher from 10 to 34
(e) m i9 a number from O to 12:
(f) n is a number from 0 to 3
y ordinarily will have a value of from about S to about 29.
As will be clear from Formula I, the glycine may he bound in the
complex or it may be absent. The presence or absence of the glycine
in the complex will determine the amount of unbound glycine or other
buffer that may be incorporated in the composition to increase the
pH to a level of from about 2.5 to about 4.5 or the preferred pH of
about 2.8 to about 3.8.
A number of aluminum zirconium polychlorohydrate complexes are
known in the prior art which are useful for the present purpose~.
By way of example, the fo~lowing may be mentioned along with their
empirical formulas: aluminum zirconium tetrachlorohydrate
(A14Zr(OH)12C14~; aluminum zirconium tetrachlorohydrate
glycine (Wickenol #E-369) ~A14Zr(OH)12C14) . NH2CH2COOH);
aluminum zirconium trichlorohydrate (A14Zr(OH)13C13); aluminum
zirconium trichlorohydrate glycine (A14Zr(OH)13C13)
. NH2CH2COOH, aluminum zirconium pentachlorohydrate
(AllOZr(OH~29C15); aluminum zirconium pentachlorohydrate
lOZr(OH)29C15) ~1H2CH2CH); aluminun
zirconium octachlorohydrate (A16Zr(OH)14C18?; aluminum
zirconium octachlorohydrate glycine (A16Zr(OH)14Cl~) n
NH2CH2COOH). The aluminum zirconium polychlorohydrate complex
can be mixed individually with the ACH and AIC13 . 6H20 in
solution or powder form or in various combinationq thereof.
3;23~
The OTC Panel on antiperspirants of the Food and
Drug Administration has adopted certain nomenclatures
and specifications for various aluminum zirconium
polychlorohydrates that are useful in the pr~sent
invention. These are set out in Table A below:
~E A
Panel Adopted Metal-Halide Al/Zr
No~lature Ratio Ranqe Ratio ~e
Alum~m zirconium 2.1 dcwn to but 2.0 up to but
trichlorQhydrate ~ n~t inclu~ not incl~
1.5:1 6.0:1
Aluminum zirconium 1.5 dGwn to and 2.0 up to but
tetrachlor~hydrate incl~ 0.9:1 not mcl~
6.0:1
Alum~m zirconium 2.1 down to but 6.0 up to and
pentachlorohydrate not incl~ including
1.5:1 10.0:1
~luminum zirconium 1.5 down to and 6.0 up to and
octachlorQhydra~e inclu~ 0.9:~ includ~
10.0:1
Exceptionally good results are obtained with
aluminum/zirconium tetrachlorohydrex glycine (CTFA
nomenclature Aluminum Zirconium Tetrachloxohydrex Gly)
complexe~ employed in dry powdered form. This material
will have a particle size of up to about 70 microns.
These materials are available under the trade names
WICKENOL-369TM (Wickhen), REZAL 36 GPT~ (Reheis) and
WESTCHLOR ZR 35 BTM (Westwood).
The quantity of active antiperspirant material
usable in this invention may vary depending upon the
nature of the other ingredients selected and the results
desired. Usually, this will comprise from about 5% to
about 30% by weight based on the total weight of the
composition with the best results being obtained when
the active antiperspirant constituted from about 10% to
about 25% on the same weight bases.
It is often highly desirable to also incorporate in
this composition a nonvolatile liquid emollient. This
will add to the elegance of the product giving it
enhanced organoleptic properties. Numerous nonvolatile
liquid emollients may be employed for this purpose.
These includa such materials as nonvolatile linear
polydimethylsiloxanes. Of special interest are the
dimethicones having a viscosity of from about 100 cs to
about 1,000 cs (and preferably about 350 cs).
These materials are described in the CTFA Cosmetic
Ingredient Dictionary, Third edition, 1982 of page 83,
and conform to the formula
~3 ~ ~ IS ~ - ~ ~ S~,- C ~3
These are available commercially as Silicone Fluid SF18
(General Electric~, Silicone Fluid SWS-101 (SWS
Silicones), Silicone Fluid 200 (Dow Corning).
Other suitable non-volatile oils for this purpose
(which in conjunction with the volatile silicones form
the liquid carrier for this invention) are organic oily
liquids which are non-polar in character and have (a) a
boiling point under atmospheric pressure not lower than
about 120C; (b) a speci~ic gravity between about 0.7
and ~.6, preferably between 0.7 and 1.2. These include
such materials as liquid hydrocarbons (mineral oil, Iso-
Par); fatty acid esters (isopropyl myristate, 2-ethyl
hexyl palmitate); diesters of dicarboxylic acids
(diisopropyl adipate) polyoxyalkylene glycol esters
(polypropylene glycol 2000 monooleate); propy~ene glycol
diesters of short chain fatty acids (C8-C10) (Neobee-
M20); polyoxyethylene ethers (polyoxyethylene (4) lauryl
ether (Brij 30), polyoxyethylene (2) oleyl ether (Brij
92), polyoxyethylene (10) oleyl ether (Brij 96, Volpo
10); polyoxypropylene cetyl ether (Procetyl); higher
fatty alcohols (oleyl, hexadecyl, lauryl) propoxylated
monohydric alcohol M.W. 880-930 (Fluid AP). Mixtures of
the above non-polar liquids are equally suitable for the
purposes of this invention.
The quantity of nonvolatile liquid emollient that
will be contained in the present composition is
variable. Usually this will constitute between about 2%
to about 20% by weight based on the total weight of the
composition. The pre~erred range being from about 5%
to about 15% on the same weight basis.
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In addition to the components described above the compo~itions
of the present invention ~ay, optionally contain a number of other
ingredients. Thus it might contain processing aids, odor maskin~
agents, perfumes, coloring agents, etc. A polyethylene powder, as
for example, a pr~duct sold under the trade name Polymist B-~s
useful as a suspending aid. As an odor mas~ing aid ethylene
tridecanedioate (sold under ~he trade name Ethylene Brassylate, Musk
T-Takasago), pentadecalactone, (sold under the trade n~me Exaltolide,
by Firmenich), and 1,3,4,6,7,8 - hexahydro - 4,6,6,7,8,8 -
hexamethylcyclopenta - gamma -2 - benzopyran (sold under the trade
name Galoxolid 5~y International Flavors and Fragrances, Inc.)
have been used with advantage.
The antiperspirant suspensions of the present invention can be
generally prepared by dispersing 'cSIe hydrophobic, pyrogenic silica
in a mixture of liquid emollients and silicone, if any, and then
mixed until wet and homogeneous. Subsequently all other powders can
be added, including actives and polyethylene, if any. The above
suspension is homogenized with a Warin~ blender for 6 minutes at low
speed. Other homogenizers, such as Menton Gaulin homogenizer,
Eppenbach Homomixer can also be used in this invention.
Then perfume or masking agent is added.
The following e~amples are given to further illustrate the
present invention. It is to be understood, however, that the
invention is not limited thereto:
EXAMPLE I
A/P SUSPENSION ROLL-ON
%(W/W)
1. Al/Zr Tetrachlorohydrex Gly 24.00
2. Aerosol R972 5.00
3. Dimethicone 350 C.S. 10.00
4. Polyethylene B-6, 6 micron powder5.00
(Polymist B-6)
5. Cyclomethicone 7158 33.59
6. Cyclomethicone 7207 22.39
7. Ethylene Brassylate 0 02
.
EXAMP LE I I
-
BA 3457-21
~ ( W/W )
1. Aluminum chlorohydrate impalpable powder 24.00
2. Aeros~l R972 5.00
3. Dimethicone 350 C.S. 10.00
4. Polyethylene B-6, 6 micron powder 5.00
5. Cyclomethicone 7158 33 59
6. Cyclo~ethicone 7207 22.39
7. Ethylene Brassylate _ 0.02
10~. 00
EXAMPLE 11 I
_
BA 3457-22
% (W/W )
1. Aluminum Sesquichlorohydrate-Gly 24.00
2. Aerosol R972 5.00
3. Dimethicone 350 C.S. 10.00
4. Polyethylene B-6, 6 micron powder 5.00
5. Cyclomethicone 7158 33.59
6. Cyclomethicone 7207 22.39
7. Ethylene Brassylate 0.02
100.00
To compare the stability of anhydrous antiperspiran~ suspension
type products containing Cab-O-Sil M5 or Bentone 38 on the one hand
and pyrogenic hydxophobic silicas employed in the present invention
(e.g. Aerosol R972; Cab-O-Sil N70-TS) a series of compositions were
prepared. After the products were prepared the following character-
istics were observed and recorded (1) appearance, (2) initial
viscosity (#6 sp. 20rpm), (33 color, (4) viscosity after standing
overnight, (S) % separation of product. These are summarized in the
Table below.
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TABLE
BA 3234-
92A 7 2B 92C 92D
Ingredient ~~W/W ~ W/W _ ~ W/W _ ~ W/W
WICKENOL 369 24 24 24 24
lAl/Zr tetrachloro-
hydrex gly) _ _ _ _
Cyclomethicone 7158 71 71_ 71 _ _71 _
Cab-O-Sil M5 _ _ 5.0
Aerosol R 972 ~ 5.0
Bentone 38 _ - *5~
Cab-O-Sil N-70 TS - - 5~ -
(Hydrophobic)
00 _ 100_ 100 100
~ppearance NON
FLOWABILITY FL~ABLE FLOWABLE FLOWABLE FLOWABLE
_ PASTE SUSPENSION_ SUSPENSION SUSP~NSION
VISCOSITY OVE~ S,o00 2100 CPS 1,000 CPS 760 CPS
~IGHT _ ALMOST ALMOST
NO NO
% SEPARATION CREAM10% SEPARATION SEPARATION SEPARATION
* Bentone 38 added as a 10% gel in Cyclomethicone 7158.
As will be noticed from the table the product with 5~ Cab-O-Sil M5
tBA3234-92A) was not a flowable suspension but a cream. The product
using 5~ Bentone 38 showed a 10% sepaxation tBA3234-92B) whereas
BA3234-92C and BA3234-92D that employ the pyrogenic hydrophobic
silicas defined in the present invention show almost no separation
despite a low viscosity.
