The present invention relates to cleansing andlor exfoliating anhydrous granules that
are useful for personal skin care.
5
The skin is the protective barrier for the human body. It protects the interior of the
body from physical injury (such as trauma) and biological injury (such as bacteria, viruses
or fungi). The skin of the human body comprises the dermis and the epidermis. The
epidermis is the top most layer of the skin, and its superficial layer is called the stratum
10 corneum.
The stratum corneum, or horny layer, is normally made up of 10 to 30 layers of dead
cells. These cells are constantly being replaced by new cells from below. It is estimated
that in adult skin it takes about a month for the stratum corneum to be completely replaced
by new cells. The replacement time increases with aging, until around 120-150 days. The
15 longer it takes to replace the dead cells, the more layers of dead cells accumulate.
It is therefore desirable to eliminate excess layers of dead skin cells from the skin
surface in order to provide a shiny skin with a youthful appearance. The process of
removing dead skin cells from the skin surface is called exfoliation.
20 Currently, human skin is cleaned andlor exfoliated using a number of different ways,
such as cleansing products with or without mechanical scrubbing using hard particles of
any kind. These particles are also called scrub beads; they are used in solid form. It is
known that the addition of scrub beads, such as perlite beads, provides a stronger and
better cleansing ability to the skin, in particular pore cleansing. Scrubbing particles can be
25 added to a number of cosmetic compositions, including creams, gels and, more recently,
to powder.
Cosmetic compositions known as powder cleansers have been in the market,
however sdch compositions are invariably composed of fine powder (i.e. less than 100
30 micrometers), such as surfactants and fillers and, during application of such products,
there are high chances that the dusting caused by the composition may cause irritation
and allergy through inhalation of powder particles. Moreover, these compositions tend to
be highly hygroscopic and the scrub particles used in some commercial powder cleansers
have a biodegradability concern.
35
There is thus a need for stable cleansing andlor exfoliating compositions presenting
a scrub-like effect, without the use of scrub beads such as perlite beads.
There is also a need for stable cleansing andlor exfoliating compositions providing
reduced dusting and hygroscopicity.
5 Moreover, there is a need for exfoliating compositions with the properties mentioned
above, and meanwhile which are biodegradable and easily spreadable on skin, with good
dissolution and foaming properties.
The Applicant has now discovered that it is possible to formulate compositions in the
10 form of anhydrous granules having the desired properties as described above, by
combining specific fatty acids with a neutralizing agent, a polyol and a filler.
Accordingly, the present invention relates to an anhydrous granule comprising:
a) at least one saturated fatty acid having 12 to 18 carbon atoms;
b) at least one neutralizing agent;
c) at le,ast one polyol; and
d) at least one filler.
The anhydrous granule of the invention may be used as a facial or body cleanser
20 andlor exfoliating composition. Moreover, the anhydrous granule of the invention is stable
without softening over time andlor temperature change. By "stable", it is meant that the
anhydrous granule does not undergo any significant change in its structure or properties
for at least one month after its manufacture and especially for at least two months after its
manufacture.
25
By "granule", it is meant a solid particle made by a granulation process. The
granulation process typically uses a powder mixture as a starting material, in order to
obtain granules. By "solid", it is meant a palticle which does not flow under its own weight.
By "anhydrous", it is meant that the granule comprises less than 5% of water by weight
30 relative to the total weight of the dry granule, preferably less than 3% by weight, preferably
less than I % by weight. Preferably, the anhydrous granule is totally devoid of water.
The anhydrous granule has preferably a particle size by volume Dv90 ranging from
250 micrometers to 850 micrometers. The anhydrous granule has preferably a particle
size by volume Dv50 ranging from 400 micrometers to 600 micrometers.
35
Preferably, said particle size range of the anhydrous granule of the invention confers
an appearance of scrub-like texture, and this, without addition of scrub particles. The size
range confers to the anhydrous granule the 2-in-1 property of cleansing and scrubbing.
The median particle size by volume Dv90 as disclosed in the present invention is a
5 parameter for particle size distribution, referring to the maximum particle diameter below
which 90% of the sample volume exists (see in A Basic Guide To Particle
Characterization, page 10, published by Malvern Instruments Limited in 2012). Likewise,
the median particle size by volume Dv50 as disclosed in the present invention is a
parameter for particle size distribution, referring to the maximum particle diameter below
10 which 50% of the sample volume exists.
The particle size by volume Dv90 and Dv50 of the anhydrous granule may be
measured by static light scattering using a commercial granulometer such as the
MasterSizer 3000 instrument from Malvern, with the aid of a Dry Powder Dispenser. The
data are processed on the basis of the Mie scattering theory. This theory, which is exact
15 for isotropic particles, makes it possible to determine, in the case of non-spherical
particles, an "effective" particle diameter. This theory is especially described in the
publication by Van de Hulst, H.C., "Light Scattering by Small Particles," Chapters 9 and,
10, Wiley, New York, 1957.
20 Preferably, the anhydrous granule according to the invention does not comprise any
scrub bead, notably any perlite bead. Preferably, the anhydrous granule comprises less
than 5% of scrub bead@) by weight relative to the total weight of the dry granule,
preferably less than 3% by weight, preferably less than 1% by weight. Preferably, the
anhydrous granule is totally devoid of any scrub bead.
25 According to another embodiment, the anhydrous granule according to the invention
may comprise at least one scrub bead, preferably perlite beads.
The present invention also relates to a cosmetic composition for cleansing and/or
exfoliating the skin comprising, in a physiologically acceptable medium, at least one
30 anhydrous granule as defined above.
The present invention also relates to a process for preparing the anhydrous granule
of the invention, comprising the following steps:
i) mixing at least one saturated fatty acid having 12 to 18 carbon atoms with at least
one neutralizing agent and at least one polyol;
ii) mixing the mixture of step i) with at least one filler and submitting the resulting
mixture to a granulator, so as to obtain wet granules; and
iii) drying the wet granules of step ii), which are optionally sieved, in order to obtain
anhydrous granules.
The present invention also relates to a method for cleansing andlor exfoliating the
keratin materials, in part~cularth e skin, comprising the application to the keratin materials,
in particular the skin, of the anhydrous granule as described above, or of the above
mentioned cosmetic composition.
The present invention also relates to the use of the anhydrous granule as defined
above, for cleansing andlor exfoliating keratin materials, in particular the skin. It also
relates to the use of the cosmetic composition as described above, for cleansing andlor
exfoliating keratin materials, in particular the skin.
Such a cosmetic composition is a rinse off product. Thus, such a cosmetic
composition is applied on skin (i.e. face andlor body), and then rinsed.
Other subjects and characteristics, aspects and advantages of the invention will
emerge even more clearly on reading the description and the examples that follows.
In that which follows and unless othehise indicated, the limits of a range of values
are included within this range, in particular in the expressions "of between" and "ranging
from ... to ...".
Moreover, the expression "at least one" used in the present description is
equivalent to the expression "one or more".
Throughout the instant application, the term "comprising" is to be interpreted as
encompassing all specifically mentioned features as well optional, additional, unspecified
ones. As used herein, the use of the term "comprising" also discloses the embodiment
wherein no features other than the specifically mentioned features are present (i.e.
"consisting of').
The anhydrous granule of the invention comprises:
a) at least one saturated fatty acid having 12 to 18 carbon atoms;
b) at least one neutralizing agent;
c) at least one polyol; and
d) at least one filler.
The saturated fatty acid having 12 to 18 carbon atoms a) is preferably chosen from
myristic acid, lauric acid, palmitic acid, stearic acid and mixtures thereof. Preferably the
saturated fatty acid having 12 to 18 carbon atoms a) has 12 to 14 carbon atoms.
Preferably, it is chosen from myristic acid, lauric acid and mixtures thereof.
5
Preferably, the anhydrous granule comprises a mixture of myristic acid and lauric acid.
Preferably the weight ratio myristic acid : lauric acid is comprised between 1 and 1.5.
The saturated fatty acid a) used in the present invention is preferably present in an
10 amount ranging from 2% to 30% by weight of the total weight of the anhydrous granule,
more preferably from 10 to 20% by weight.
The anhydrous granule of the invention further comprises at least one neutralizing
agent b). Said neutralizing agent b) may be chosen from mineral bases such as
15 potassium hydroxide, sodium hydroxide or ammonium hydroxide. It may be chosen from
organic bases, in particular alkanolamines such as isopropanolamine, mono-, di- and
triethanolamine, aminoethylpropanol and aminomethylpropanol.
The neutralizing agent b) is preferably chosen from mineral bases, preferably is
potassium hydroxide or sodium hydroxide. The amount of base used depends on the
20 amount of fatty acid(s) a) present in the anhydrous granule. A sufficient amount of base
must be used to neutralize the fatty acid(s) a). Preferably, the fatty acid@) a) is 90 to
loo%, more preferentially95 to loo%, neutralized. The neutralizing agent b) used in the
present invention is preferably present in an amount ranging from 3% to 15% by weight of
the total weight of the anhydrous granule, preferably from 5% to 10% by weight.
25
The anhydrous granule of the invention further comprises at least one polyol c). By
"polyol", it is meant any organic molecule comprising at least two free hydroxyl groups.
The polyol c) is preferably a polyol comprising from 2 to 8 carbon atoms. Preferably the
polyol c) is chosen from glycerol, sorbitol, glycols such as butylene glycol, propylene
30 glycol, isoprene glycol, dipropylene glycol, hexylene glycol and polypropylene glycol.
Preferably the polyol c) is sorbitol.
The polyol c) used in the present invention is preferably present in an amount
ranging from 5% to 30% by weight of the total weight of the anhydrous granule, more
35 preferably from 10 to 20% by weight.
U
The anhydrous granule of the invention further comprises at least one filler d). The
filler d) may be chosen from talc, starch such as corn starch, kaolin, mica, sericite, silica
and notably hydrophobic colloidal silica, polyamide powders, poly-p-alanine powders,
polyethylene powders and tetrafluoroethylene polymer powders. Preferably the filler may
5 be chosen from talc, starch such as corn starch, kaolin, mica and sericite.
The filler d) used in the present invention is preferably present in an amount ranging
from 40% to 80% by weight of the total weight of the anhydrous granule, more preferably
from 45 to 70% by weight.
10
According to a preferred embodiment, the present invention relates to an anhydrous
granule comprising, by weight of the total weight of said anhydrous granule:
a) from 10 to 20% by weight of at least one saturated fatty acid having 12 to 18
carbon atoms, preferably chosen from myristic acid, lauric acid and mixtures
thereof;
b) from 5 to 10% by weight of at least one neutralizing agent, preferably chosen
from mineral bases;
c) from 10 to 20% by weight of at least one polyol, preferably comprising from 2 to
8 carbon atoms; and
d) from 45% to 70% by weight of at least one filler, preferably chosen from talc,
starch such as corn starch, kaolin, mica and sericite.
The anhydrous granule of the present invention may comprise at least one additive.
A person skilled in the art can adjust the type and amount of additives present in the
25 anhydrous granules according to the invention by means of routine operations, so that the
desired cosmetic properties and stability properties for these anhydrous granules are not
affected by the additives. Said additive may be chosen from emollients, colorants,
fragrances and active agents.
The emollients may be chosen from polyoxylenated polyethylene glycol andlor shea
30 butter.
The colorants may be chosen from pigments, dyes and nacres. Pigments include
white or colored particles, mineral or organic, intended for coloring and/or opacifying the
resultant product. Preferably, pigments or nacres, if present, are present in an amount
ranging from 0.02 to 30% by weight, more preferably from 0.01 to 20% by weight relative
35 to the total weight of the anhydrous granule.
The fragrance may preferably be menthol.
The active agents may be chosen form vitamins, antioxidants and vegetal extracts,
such as Camellia sinensis leaf extract or charcoal powder.
The present invention also relates to a cosmetic composition, notably for cleansing
5 andlor exfoliating keratin materials, in particular the skin, comprising, in a physiologically
acceptable medium, at least one anhydrous granule of the invention as described above.
The anhydrous granule according to the invention may be applied by any means
enabling a uniform distribution, in particular using a finger, or a cotton ball, a rod, a brush,
10 gauze, or a spatula, and can be removed by rinsing with water.
The anhydrous granule of the invention may be implemented so as to improve the
general state of the epidermis, in particular the skin.
The present invention also relates to a process for preparing the anhydrous granule
15 of the invention, comprising the following steps:
i) mixing at least one saturated fatty acid having 12 to 18 carbon atoms with at least
one neutralizing agent and at least one polyol;
ii) mixing the mixture of step i) with at least one filler and submitting the resulting
mixture to a granulator, so as to obtain wet granules; and
20 iii) drying the wet granules of step ii), which are optionally sieved, in order to obtain
anhydrous granules.
Such a process of the invention is easy to perform, and without issues such as dust
generated during production.
25 Sfep i) of the above process comprises mixing at least one saturated fatty acid
having 12 to 18 carbon atoms with at least one neutralizing agent and at least one polyol.
It may be performed under heating, preferably at a temperature comprised between 60°C
and 80°C.
The resulting mixture obtained in step i) is mixed with at least one filler, and then
30 submitted to a granulator, so as to obtain wet granules. Preferably said step is performed
at room temperature. Preferably the granulator is a Rapid Mixing Granulator, a Sigma
Mixer, or a Universal Mixer.
The wet granules obtained in step ii) are finally dried, so as to obtain anhydrous
granules of the invention. Before or after drying, the wet granules are preferably sieved,
35 preferably through a mesh having the required size for obtaining a Dv90 particle size of
250 to 850 pm. Drying can be performed in an industrial Tray Drying Oven with hot air
circulation or in a Fluid Bed Drier. Drying temperature should be between 30°C and 60°C,
preferentially between 40°C and 50°C.
The present invention also relates to a method for cleansing andlor exfoliating
5 keratin materials, in particular the skin, comprising the application to the keratin materials,
in particular the skin, of the anhydrous granule of the invention, or of a cosmetic
composition comprising said anhydrous granule.
The invention also relates to the use of the anhydrous granule of the invention, or of
a cosmetic composition comprising said granule, for cleansing andlor exfoliating keratin
10 materials, in particular the skin.
The following examples serve to illustrate the invention without, however, being
limiting in nature.
15 EXAMPLES
Example 1: Preparation of a composition accordinq to the present invention
Composition I has the following composition:
-
Phase Raw material
Lauric acid
Myristic acid
Sorbitol
B KOH (50% in water)
20
Composition I was included in the following composition (composition la) according to the
process detailed below, in order to obtain anhydrous granules according to the present
invention:
Composition la
I
Comoosition I
TALC 7,3
POLYETHYLENE
In a vessel, the lauric acid, myristic acid and sorbitol solution are weighted and heated up
to 70°C. Potassium hydroxide is added for neutralization of fatty acids, and a "play dough"
soap component is formed: this corresponds to composition I.
5 At room temperature, 41.85% of composition I is mixed with ingredients of phase A, and
then granulated in a Stephan UMC 5 with double jacket and granulating insert at 300 rpm
and room temperature. The resulting wet granules are sieved through a mesh size -18-20
(for obtaining dry granules of Dv9O of between 250pm and850pm) and dried at 50°C until
Loss on Drying (LOD) < 5%. Phase B is mixed with the dry granules as the final step.
10 Finally, anhydrous granules according to the present invention are obtained.
Composition I was also included in the following composition (composition lb) according to
the process detailed above, in order to obtain' anhydrous granules according to the
present invention:
Composition Ib
IPhase/ Raw material
Concentration
POLYETHYLENE 1 I
A 1 BLUE 1 LAKE
A 1 IRON OXIDES
A
I
A I SILICA
I ZEA MAYS (CORN)
FRAGRANCE 0,4
TALC 3,6
LEAF EXTRACT (and)
DEXTRIN
0,Ol
a The anhydrous granules of the present invention (granulated cleanser of
composition la) were evaluated by the Sensory Expert Foam Panel (15 to 16 women) in
China and compared with Biore Baking Soda, a commercial product notably comprising
5 sodium bicarbonate, citric acid, sodium cocoyl isethionate, starch and silica.
The method used for the comparison was objective evaluation of sensory characteristics
by said trained expert panel using standard criteria and gesture, in which the panelists
give scores to each attribute.
The results show that the granulated cleanser of the invention has more coverage on
10 application and stronger rinse-off ability, and also less dry and tight skin finish. The
granulated cleanser also has stronger foam density, homogeneity and volume, and
smaller size of bubbles.
e The granulated cleanser of composition la was also compared with Garnier
15 Matcha Foam. Garnier Matcha Foam has the following composition:
I Raw material I Concentration (% wlw) I
WATER
The granulated cleanser of the invention (i.e. composition la) was significantly higher on
spreadability, dissolution, speed & quantity of foaming and bigger size bubbles, and
significantly lower on sticky. In addition, the average amount of water and number of
splashes required for rinse off of granulated powder cleanser was lower than of Matcha
Foam. This test was performed by a QDA panel, in which the scores for each attribute are
given as a relative profile between both formulas.
5 0 A study with 15 volunteers was also performed to comparing the average quantity
per use of the granulated cleanser of the present invention with the above-mentioned
soap-based gel formula (Garnier Matcha Foam). For this study, the volunteers used the
products at home for 7 days and were asked back to use the product in front of the
evaluator, who weighed the packs before and after the volunteer's use. The average
10 weight difference was used to compare the quantity per use of each product.
The results show that the average quantity per use of the granulated cleanser of the
invention is lower than the soap-base benchmark (0.319 against 0.869 per use).
Thus, the granulated cleanser of the invention is efficient for cleansing at smaller average
quantity per use.
15
Example 2: Preparation of a com~ositiona ccordinq to the present invention
Composition I1 has the following composition:
1 A 1 Lauric acid 1 17.32 I
Phase
Myristic acid -23,09
Sorbitol Qs 100
-- --
Raw material
KOH (50% in water)
20 Composition Ill has the following composition:
Phase Raw material
Concentration
Fragrance 1 20 1
A
6 Iron oxides
Compositions II and Ill were included in the following composition according to the
process detailed in Example 1, in order to obtain anhydrous granules according to the
present invention:

CLAIMS
1. An anhydrous granule comprising:
5 a) at least one saturated fatty acid having 12 to 18 carbon atoms;
b) at least one neutralizing agent;
c) at least one polyol; and
d) at least one filler.
2. The anhydrous granule of claim 1, wherein the saturated fatty acid a) is
chosen from myristic acid, lauric acid, palmitic acid, stearic acid and mixtures thereof.
3. The anhydrous granule of claim 1 or 2, wherein the saturated fatty acid
a) is present in an amount ranging from 2% to 30% by weight of the total weight of the
15 anhydrous granule.
4. The anhydrous granule of any one of claims I to 3, wherein the
neutralizing agent b) is chosen from mineral bases, preferably from potassium and sodium
hydroxides.
5. The anhydrous granule of any one of the claims 1 to 4, wherein the
polyol c) is a polyol comprising from 2 to 8 carbon atoms, and preferably chosen from
glycerol, sorbitol, and glycols such as butylene glycol, propylene glycol, isoprene glycol,
dipropylene glycol, hexylene glycol and polypropylene glycol.
25
6. The anhydrous granule of any one of the claims 1 to 5, wherein the
polyol c) is present in an amount ranging from 5% to 30% by weight of the total weight of
the anhydrous granule.
30 7. The anhydrous granule of any one of the claims 1 to 6, wherein the filler
d) is chosen from talc, starch such as corn starch, kaolin, mlca, sericite, silica and notably
hydrophobic collo~dal sll~ca, polyamide powders, poly-p-alanine powders, polyethylene
powders and tetrafluoroethylene polymer powders.
35 8. The anhydrous granule of any one of the claims 1 to 7, wherein the filler
d) is present in an amount ranging from 40% to 80% by weight of the total weight of the
anhydrous granule.
9. The anhydrous granule of any one of claims 1 to 8, wherein it has a
particle size by volume Dv9O ranging from 250 micrometers to 850 micrometers.
$0. A process for preparing the anhydrous granule according to any one of
claims 1 to 9, comprising the following steps:
i) mixing at least one saturated fatty acid having 'I2 to 18 carbon atoms with at least
one neutralizing agentand at least one polyol;
ii) mixing the mixture of step i) with at least one filler and submitting the resulting
mixture to a granulator, so as to obtain wet granules; and
iii) drying the wet granules of step ii), which are optionally sieved, in order to obtain
anhydrous granules.
1 1. A cosmetic composition comprising, in a physiologically acceptable
15 medium, at least one anhydrous granule according to any one of claims 1 to 9.
f2. A method for cleansing andlor exfolialing the [keratin materials, in
pariicular Lhe skin, corriprising tiie applicatiori to the Ikeraiin materials, in pai-iicular the
skin, of the anhydrous granule of any one of claims I lo 9, or of the cosmetic composition
20 of claim 11.
'I 3. Use of the anhydrous granule of any one of claims 1 to 9 for cleansing
andlor exfoliating lteratin materials, in particular tlae sltiia.
'14.. Use of the cosmetir; coinposiiio~~of cciaim 'I 1 far cleansing and101
e:cioliating lteraiin materials, in pariicholar the slcin.