Note: Descriptions are shown in the official language in which they were submitted.
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SKIN TONING FORMULATION
DESCRIPTION OF THE PRIOR ART
End-users are becoming increasingly ' a~aare~ '~~~t~
undesirable skin conditions can be caused or aggravated by
S inherent skin oil or by oils found in various products
including cosmetics. One of the most undesirable skin
conditions is acne.
Prior art skin cleansing compositions have
attempted to absorb oil and debris from skin surfaces.
l0 These skin cleansing compositions can be described
variously as oil-based, emulsion-type or water-based
surfactant systems.
Oil-based skin cleansing compositions contain a
mixture of oils and esters. These compositions can be an
15 irritant particularly when used on sensitive skin, because
they may contain surfactants and because they tend to
leave a greasy film over the skin. Emulsion-type skin
cleansing compositions are usually based on a class of
surfactants known as emulsifiers. Any surfactants can be
20 irritant, especially when used around the eyes.
Oil-in-water emulsions are the most common, but
water-in-oil emulsions are also available. Emulsion-type
preparations contain oil and/or waxes and tend to leave a
greasy feel on the skin.
25 To alleviate this problem, U.S. Patent No.
5,480,633 attempts to provide for an aqueous skin rinse
formulation for soap and surfactant residues. The claim is
made that the facial rinse provided by the invention is
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effective in reducing the deposition of soap and
surfactants from the skin.
There exists products which attempt to visibly
control oily facial shine via oil-absorbing powders. These
products do not possess antiseptic properties, and
furthermore, are aesthetically unappealing by virtue of
their viscous, chalky appearance, and/or lack of
homogeneity.
The present invention provides for non-oily
leave-on skin cleansing compositions having astringent,
antiseptic, oil-stripping properties with long lasting oil
control.
SUMMARY OF THE INVENTION
The present invention provides for leave-on skin
cleanser compositions having astringent, antiseptic and
oil stripping properties. The compositions comprise as
essential ingredients an oil-absorbing powder, thickening
and keratolytic agents and alcohol. The compositions of
the invention also comprise water, fragrances, colorants,
an emollient and a humectant. The oil-absorbing powder is
in an amount from about 1 to about 3 wt o, the thickening
agent in an amount from about 0.1 to about 1 wt. o, the
keratolytic agent in an amount from about 0.01 to about 2
wt. o and the.alcohol in an amount from about ZO to about
40 wt. o.
The invention also provides for a method of
preparing the compositions of the invention. The oil-
adsorbing powder and the thickening agent are admixed in
water to form a suspension. The pH of the suspension is
adjusted to from about 3 to about 4. The keratolytic agent
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is dissolved in alcohol to form an acid-alcohol mixture and
the pH of the mixture adjusted to from about 3 to about 4.
The suspension and the acid-alcohol mixture are combined and
the pH adjusted to from about 3 to about 4. A humectant is
admixed with the suspension and an emollient is mixed with
the acid-alcohol mixture.
According to one aspect of the present invention,
there is provided a leave-on skin cleanser and astringent
composition comprising: an oil-absorbing powder in an amount
from about 1 to about 3 wt. %; a thickening agent in an
amount from about 0.1 to about 1 wt.; a keratolytic agent in
an amount from about 0.01 to about 2 wt. o; an alcohol in an
amount from about 10 to about 40 wt. o, said alcohol
selected from the group consisting of ethyl alcohol and
isopropyl alcohol; and q.s. water, fragrances and colorants,
wherein said composition is adjusted to a pH of from about 3
to about 4, wherein said composition is in the form of a
suspension.
According to another aspect of the present
invention, there is provided a leave-on skin cleanser and
astringent composition comprising: a hectorite-type clay in
an amount from about 1 to about 3 wt. %; xanthan gum in an
amount from about 0.1 to about 1 wt. o; salicylic acid in an
amount from about 0.1 to about 2o; an alcohol in an amount
from about 10 to about 40 wt. o, said alcohol selected from
the group consisting of ethyl alcohol and isopropyl alcohol;
and q.s. water, fragrances and colorants, wherein said
composition is adjusted to a pH of from about 3 to about 4,
wherein said composition is in the form of a suspension.
According to still another aspect of the present
invention, there is provided a leave-on skin cleanser and
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astringent composition comprising: about 2 wt. o lapoinite~;
about 0.25 wt. % xanthan gum; about 2 wt. o salicylic acid;
about 20 wt. o alcohol; and q.s. water, fragrances and
colorants, wherein said composition is adjusted to a pH of
from about 3 to about 4, wherein said composition is in the
form of a suspension.
According to yet another aspect of the present
invention, there is provided a leave-on skin cleanser and
astringent composition prepared by the steps of: admixing in
water an oil-absorbing powder in an amount from about 1 to
about 3 wt. % and a thickening agent in an amount from about
0.1 to about 1 wt. o to form a suspension, and adjusting the
pH of said suspension to from about 3 to about 4; dissolving
a keratoyltic agent in an amount from about 0.01 to
about 2 wt. % in from about 10 to about 40 wt. o alcohol to
form an acid-alcohol mixture, said alcohol selected from the
group consisting of ethyl alcohol and isopropyl alcohol, and
adjusting the pH of said mixture to from about 3 to about 4;
and combining said suspension and said acid-alcohol mixture
to form said composition and adjusting the pH of said
composition to from about 3 to about 4.
According to a further aspect of the present
invention, there is provided a leave-on skin cleanser and
astringent composition prepared by the steps of: admixing in
water laponiteTM in an amount from about 1 to about 3 wt.
and xanthan gum in an amount from about 0.1 to about 1 wt.
to form a suspension, and adjusting the pH of said
suspension to from about 3 to about 4; dissolving salicylic
acid in an amount from about 0.01 to about 2 wt. o in from
about 10 to about 40 wt. o alcohol to form an acid-alcohol
mixture, said alcohol selected from the group consisting of
ethyl alcohol and isopropyl alcohol, and adjusting the pH of
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said mixture to from about 3 to about 4; and combining said
suspension and said acid-alcohol mixture to form said
composition and adjusting the pH of said composition to from
about 3 to about 4, wherein said composition is in the form
of a suspension.
The invention further provides for a method for
cleansing the skin. The method comprises the step of
applying to the skin an effective amount of the compositions
of the invention, allowing the applied composition to dry
completely and then leaving the dried compositions on the
skin area for continual oil absorbancy and shine control.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The novel compositions of this invention provide
for an aqueous topical formulation having astringent,
antiseptic and oil stripping properties.
The novel compositions comprise four classes of
essential ingredients in a suitable carrier. The four
classes are generally defined as oil absorbing powders,
thickening agents, keratolytic agents and a lower alkyl
alcohol.
The oil absorbing powder is any substance which is
capable of removing oil secretions from the skin. Exemplary
oil absorbing powders include cornstarch, oatmeal, talc,
silica coated mica, titanium dioxide coated mica and
hectorite type-clay. The oil absorbing powder is present in
an amount from about 1 to about 3 wt. o, preferably in an
amount from about 1.8 to about 2.2 wt. %.
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The term "hectorite-type clay" as used herein
includes both naturally occurring and synthetic hectorite
clays such as those available commercially from southern
Clay Products, Inc., under the trade name Laponite XLS and
XLG. They are already known in the art and are used in
the personal care and cosmetic areas, namely in such
products as shampoos, face masks, moisturizing creams and
TM
makeups. Some of the advantages of Laponite include
improving the application and feel of lotions and creams,
stabilizing emulsions, suspensions and solutions, reducing
the oily feel of emulsions and acting as an absorbent for
grease and oil. Laponite is a preferred oil-absorbing
powder because it not only contributes to a.better feel of
the composition but provides immediate visible perception
of absorption of skin oil.
The compositions of this invention also include
a thickening agent. Exemplary thickening agents include
those made from bentonite, carbomer, carrageenan,
ozokerite, dextrin, gelatin and a cellulose resin such as
xanthan gum. The thickening agent is present in an amount
from about 0.1 to about 1 wt. %, preferably in an amount
from about 0.23 to about 0.27 wt. %.
Xanthan gum is available commercially under the
TM
trade name Keltrol. Xanthan gum is a high molecular weight
polysaccharide which has been used in food and
pharmaceutical applications. As provided commercially,
xanthan gum particles typically range in size from 75 to
250 microns. Xanthan gur,~, ~s a preferred thickening agent
for maximum suspension activity with minimal viscosity,
Compositions of this invention also include a
keratolytic agent. Exemplary agents are salicylic acid,
boric acid and methyl salicylate. The keratolytic agent is
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present in an amount from about 0.01 to about 2 wt. o,
preferably from about 0.5 to about 1.5 wt. o.
Salicylic acid is known as a topical keratolytic
agent and externally as an antiseptic and antifungal
agent. Salicylic acid acts as an astringent and
accelerates the removal of horny cells by decreasing their
stickiness or cohesion. Salicylic acid is a preferred
keratolytic agent as it combines maximum efficacy with
antisepsis while offering ease of solubilization.
Alcohol is an essential ingredient on the novel
compositions of the invention, particularly lower alkyl
alcohols. Exemplary alcohols are ethyl alcohol, isopropyl
alcohol and mixtures thereof. The alcohol is suitable as a
vehicle for the keratolytic agent and acts as an
antiseptic and astringent. The alcohol is present in the
compositions in an amount from about 10 to about 40 wt. %,
preferably from about 20 to about 30 wt. %.
In addition to the essential ingredients, the
compositions of this invention can also contain
nonessential ingredients. These are generally humectants,
emollients, colorants, fragrances and the like.
Emollients which can be included in the
compositions of the invention function by their ability to
remain on the skin surface or in the stratum corneum to
act as lubricants, to reduce flaking, and to improve the
skin appearance. Typical emollients include fa~.ty esters,
fatty alcohols, mineral oil, polyether siloxane copolymers
and the like. Examples of emollients include but are not
limited to PPG-15 stearyl ether, PPG-10 cetyl ether,
steareth-10, oleth-8 and PPG-4 lauryl ether. The emollient
is preferably PPG-15 stearyl ether and can be present in
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an amount up to about 5 wt %, preferably up to about 2.5
wt. %. ,
Humectants of the polyhydric alcohol-type can be ,
included in the compositions of the invention. The
5. humectants aid in increasing the effectiveness of the
emollient, reduce scaling, stimulate removal of built-up
scale and improve skin feel. Typical polyhydric alcohols
include glycerol (also known as glycerin), polyalkylene
glycols, and more preferably alkelene polyols and their
derivatives, including propylene glycol, dipropylene
glycol, polypropylene glycol, polyethylene glycol and
derivatives thereof, sorbitol, hydroxypropyl sorbitol,
hexylene glycol, 1,3-dibutylene glycol, 1,2,6,-
hexanetriol, ethoxylated glycerol, propoxylated glycerol
I5 and mixtures thereof. For best results, the humectant is
preferably 1,3-dibutylene glycol and can be present in an
amount up to about 5 wt. %, preferably up to about 2.5 wt.
%.
Additional nonessential components include well
known colorants such as FD&C Blue #1 and D&C Yellow #10
and fragrances such as eucalyptus oil, camphor synthetic,
peppermint oil and clove oil. For best results, colorants
may be present as needed, in an amount up to about 1 wt.
%, preferably up to about 0.5 wt. %. Fragrances may be
present as needed in an amount up to about 0.5 wt. %,
preferably up to about 0.36 wt. %.
According to the present invention, the oil
absorbing powder, thickening agent and keratolytic agent
are admixed with a suitable vehicle or carrier system.
Preferred carriers include water for the oil-absorbing
powder and the thickening agent. The water is admixed in
an amount as needed and the keratolytic agent is admixed
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with the alcohol. The nonessential components are admixed
where needed in a suitable vehicle or carrier system.
Preferred carriers include water for the humectant and
alcohol for the emollient and fragrances.
The oil-absorbing powder and thickening agent
are first admixed in water to form a suspension.
Optionally, a humectant can also be admixed. Following
admixing, the pH is adjusted to from about 3 to about 4
using art-known acids. A preferred acid is citric acid.
The keratolytic agent is admixed in alcohol to
form an acid-alcohol mixture. Optionally, the emollient
and fragrances can also be admixed with the acid-alcohol
mixture. Following admixing, the pH is adjusted to from
about 3 to about 4 using art-known bases. A preferred base
is potassium hydroxide.
The water suspension and the acid-alcohol
mixture are combined. Optionally, colorants can be admixed
and the pH adjusted to from about 3 to about 4, preferably
to from about 3.3 to about 3.5.
The novel compositions of the invention result
in a skin cleansing astringent, antiseptic and oil-
stripping formulation. The formulation is in the form of
an aqueous suspension which can be applied as a leave-on
skin cleanser. The compositions of the invention are
applied to the face (or other skin surface) and the
applied composition is allowed to dry completely. The
dried composition is left on the skin surface for
continual oil absorbancy and shine control.
The invention will now be further described with
reference to the following example:
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PHASE COMPONENT wt. 9s
A Water
q.s. to 100
Laponite 2
xanthan gum 0.25
1,3-dibutylene 2
glycol
B alcohol 20
salicylic acid 2
PPG-15 2
Stearyl Ether
Fragrances q.s.
A+B Colorants q.s.
The abbreviation "q. s." is a standard dispensing
nomenclature which means "as needed" or "as sufficient".
Phase A:
Laponite is dispersed in thE. water at room
temperature and mixed for a sufficient time until
dispersed. Xanthan gum is then added to the dispersion
also at room temperature and mixed therein for a
sufficient time until the dispersion thickens.
Alternatively, xanthan gum can be first dispersed and then
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the Laponite added. Optionally, 1,3-dibutylene glycol can
be added during dispersion formation. The pH of the
dispersion is adjusted with an acid to a pH of from about
3 to about 4.
Phase B:
The salicylic acid and the alcohol are mixed at
room temperature until the acid dissolves in the alcohol.
Optionally, PPG-15 stearyl ether and the fragrances can be
added. The pH is adjusted with a base to from about 3 to
about 4.
Phase A+B
Phases A and B are mixed and optionally,
colorants can be added. The pH can be adjusted by addition
of an acid or a base where appropriate to a pH of from
about 3.3 to about 4. The target pH at the time of
manufacture is about 3.5.
While this specification describes the
principles of the present invention, it is to be
understood that other aspects, advantages and
modifications within the scope of the invention will be
apparent to those skilled in the art.
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