Solid anti-sun composition based on lipophilic organic UV screening agent
and aerogel particles of hydrophobic silica
The present invention thus relates to a solid composition comprising, in a
cosmetically acceptable medium:
a) at least one pulverulent phase
b) at least one lipophilic organic UV screening agent
characterized in that the pulverulent phase comprises at least aerogel particles of
hydrophobic silica exhibiting a specific surface per unit of weight (Sw) ranging
from 200 to 1500 m2/g, preferably from 600 to 1200 m2/g and better still from 600
to 800 m2/g, and a size, expressed as volume-average diameter (D[0.5]), of less
than 1500 miti and preferably ranging from 1 to 30 miti , more preferably from 5 to
25 miti , better still from 5 to 20 miti and even better still from 5 to 15 miti .
It also relates to a cosmetic method for caring for and/or making up human
keratinous substances, in particular the skin of the body or of the face or the hair,
comprising at least the application, to the surface of the keratinous substance, of
at least one composition as defined above.
It is known that radiation with wavelengths of between 280 nm and 400 nm makes
possible tanning of the human epidermis and that radiation with wavelengths of
between 280 and 320 nm, known under the name of UV-B rays, harms the
development of a natural tan. Exposure is also capable of bringing about a
detrimental change in the biomechanical properties of the epidermis which is
reflected by the appearance of wrinkles, leading to premature ageing of the skin.
It is also known that UV-A rays with wavelengths of between 320 and 400 nm
penetrate more deeply into the skin than UV-B rays. UV-A rays cause immediate
and persistent browning of the skin. Daily exposure to UV-A rays, even of short
duration, under normal conditions can result in damage to the collagen fibres and
the elastin, which is reflected by a modification to the microrelief of the skin, the
appearance of wrinkles and uneven pigmentation (liver spots, heterogeneity of the
complexion).
Many cosmetic compositions intended for the photoprotection (UV-A and/or UV-B)
of the skin have been provided to date. Formulations which provide the users with
easy application on the skin are very particularly desired. These screening
cosmetic compositions must moreover satisfy the regulations as regards
protection factor and in particular the European regulations on anti-sun products,
especially on the protection ratio between UV-B and UV-A radiation and more
particularly the SPF/PPD ratio, which must be less than 3 .
The efficacy of anti-sun compositions for UV-B protection is generally expressed
by the sun protection factor (SPF), which is expressed mathematically by the ratio
of the dose of UV radiation necessary to reach the erythemal threshold with the
UV screening agent to the dose of UV radiation necessary to reach the erythemal
threshold without UV screening agent. This factor thus concerns the efficacy of the
protection having a spectrum of biological action centred in the UV-B range and
consequently gives an account of the protection with regard to this UV-B radiation.
To characterize the protection with regard to UV-A radiation, the PPD (persistent
pigment darkening) method, which measures the colour of the skin observed 2 to
4 hours after exposure of the skin to UV-A radiation, is particularly recommended
and used. This method has been adopted since 1996 by the Japanese Cosmetic
Industry Association (JCIA) as official test procedure for the UV-A labelling of
products and is frequently used by test laboratories in Europe and the United
States (Japan Cosmetic Industry Association Technical Bulletin. Measurement
Standards for UVA protection efficacy. Issued November 2 1, 1995 and effective as
of January 1, 1996).
The UV-APPD sun protection factor (UV -Appd PF) is expressed mathematically by
the ratio of the dose of UV-A radiation necessary to reach the pigmentation
threshold with the UV screening agent (MPPDp) to the dose of UV -A radiation
necessary to reach the pigmentation threshold without UV screening agent
(MPPDnp).
UV-A^ PF - M P P
MPPDnp
Anti-sun compositions are fairly often provided in the form of an emulsion of oil-inwater
type (that is to say, a cosmetically acceptable support consisting of a
continuous aqueous dispersing phase and of a non-continuous oily dispersed
phase) or of the water-in-oil type (that is to say, a cosmetically acceptable support
consisting of a continuous oily dispersing phase and of a non-continuous aqueous
dispersed phase) which comprises, at various concentrations, one or more
conventional lipophilic and/or hydrophilic organic screening agents which are
capable of selectively absorbing harmful UV rays, these screening agents (and
their amounts) being selected as a function of the desired sun protection factor.
However, the incorporation of organic UV screening agents in this type of
cosmetic composition sometimes results in an uncomfortable cosmetic feel, in
particular a tacky effect during application to the skin, which persists over time.
These cosmetic compositions comprising organic screening agents have a
tendency to leave a glossy film at the surface of the skin.
The glossy effect contributed by the lipophilic organic UV screening agents
increases in proportion as their content in the compositions increases; it is thus
particularly high for the anti-sun compositions exhibiting high levels of SPF and
PPD protection.
In the field of anti-sun cosmetics, the formulation form in the powder form makes it
possible to avoid all these disadvantages due to the presence of fillers which
make it possible to introduce softness and mattness. Loose or compact
photoprotective powders based on inorganic UV screening agents which are
metal oxide pigments, such as titanium dioxide or zinc oxide, are known in
particular. The introduction of these inorganic screening agents into these
formulation forms results in significant coverage and in a loss of the transparency
of the product which leaves a whitening film on the skin.
There also exist, in Patent Application EP 0 839 518, cosmetic compositions in
the loose or compact powder form comprising organic screening agents
entrapped in a porous spherical silica aggregate. This type of product is less
covering than the preceding one. Nevertheless, the content of screening agent
which can be introduced into this type of formulation form remains low. For this
reason, the efficacy (SPF) of this type of product remains limited.
The need thus remains to produce anti-sun cosmetic compositions, in the loose or
compact powder form, which exhibit a high efficacy and which are transparent and
non-covering on application.
The Applicant Company has discovered, surprisingly, that this objective can be
achieved by using aerogel particles of hydrophobic silica in a solid composition
based on lipophilic organic UV screening agents, in particular in a composition in
the loose or compact powder form.
This discovery forms the basis of the present invention.
The present invention thus relates to a solid composition comprising, in a
cosmetically acceptable medium:
a) at least one pulverulent phase
b) at least one lipophilic organic UV screening agent
characterized in that the pulverulent phase comprises at least aerogel particles of
hydrophobic silica exhibiting a specific surface per unit of weight (Sw) ranging
from 200 to 1500 m2/g, preferably from 600 to 1200 m2/g and better still from 600
to 800 m2/g, and a size, expressed as volume-average diameter (D[0.5]), of less
than 1500 miti and preferably ranging from 1 to 30 miti , more preferably from 5 to
25 miti , better still from 5 to 20 miti and even better still from 5 to 15 miti .
The compositions according to the invention are provided in particular in the form
of a loose or compact powder.
It also relates to a cosmetic method for caring for and/or making up human
keratinous substances, in particular the skin of the body or of the face or the hair,
comprising at least the application, to the surface of the keratinous substance, of
at least one composition as defined above.
The term "human keratinous substances" is understood to mean the skin (body,
face, outline of the eyes), head of hair, eyelashes, eyebrows, body hair, nails, lips
or mucous membranes.
The term "cosmetically acceptable medium" is understood to mean any medium
compatible with the skin and/or its superficial body growths which exhibits a
pleasant colour, a pleasant odour and a pleasant feel and which does not cause
unacceptable discomfort (smarting, tightness, redness) liable to dissuade the
consumer from using this composition.
The term "lipophilic organic UV screening agent" is understood to mean an
organic molecule which is capable of screening out UV radiation between 290 and
400 nm and which can be dissolved in the molecular or dispersed state in an oily
phase in order to obtain a macroscopically homogeneous phase. Mention may be
made of the following examples of UV screening agents:
The term "organic molecule" is understood to mean any molecule comprising, in
its structure, one or more carbon atoms.
Within the meaning of the present invention:
- the term "solid" is intended to denote the state of the composition at ambient
temperature (25°C) and at atmospheric pressure (760 mmHg), that is to say a
composition of high consistency, which retains its form during storage. In contrast
to "fluid" compositions, it does not flow under its own weight. It is advantageously
characterized by a hardness as defined below.
- the term "compact powder" is intended to denote a mass of product, the
cohesion of which is at least partly provided by virtue of a compacting during
manufacture. In particular, by carrying out a measurement using a TA.XT.plus
Texture Analyser sold by Stable Micro Systems, the compact powder according to
the invention can advantageously exhibit a resistance to pressure of between 0.1
and 1 kg and in particular between 0.2 and 0.8 kg, with respect to the surface
area of the spindle used (in the case in point, 7.07 mm2) . This resistance is
measured by causing an SMS P/3 flat-ended cylindrical spindle in contact with the
powder to move over a distance of 2 mm at a speed of 0.5 mm/second; more
generally, this powder is obtained by compacting. The term "compact powder"
should be understood more specifically to mean that these powders exhibit a
Shore A hardness, measured using a Zwick hardness tester, which varies,
according to the intensity of the complexions under consideration, from 12 to 30°
Shore A.
- the term "loose powder" is intended to denote a mass of product which is
capable of collapsing under its own weight, such a mass being formed of particles
which are predominantly isolated and movable with respect to one another.
AEROGEL PARTICLES OF HYDROPHOBIC SILICA
A composition according to the invention also comprises aerogel silica particles
intended to stabilize the composition according to the invention by taking up a
position at the dispersed phase/continuous phase interface.
Aerogels are ultralight porous materials which were first produced by Kristler in
1932.
They are generally synthesized by a sol-gel process in a liquid medium and then
dried by extraction with a supercritical fluid. The supercritical fluid most commonly
used is supercritical CO2. This type of drying makes it possible to avoid shrinkage
of the pores and of the material.
Other types of drying also make it possible to obtain porous materials starting
from gel, namely (i) drying by freeze drying, which consists in solidifying the gel at
low temperature and in then subliming the solvent, and (ii) drying by evaporation.
The materials thus obtained are referred to respectively as cryogels and xerogels.
The sol-gel process and the various drying operations are described in detail in
Brinker C.J. and Scherer G.W., Sol-Gel Science, New York, Academic Press,
1990.
The term "hydrophobic silica" is understood to mean any silica whose surface is
treated with silylating agents, for example halogenated silanes, such as
alkylchlorosilanes, siloxanes, in particular dimethylsiloxanes, such as
hexamethyldisiloxane, or silazanes, so as to functionalize the OH groups with silyl
groups Si-Rn, for example trimethylsilyl groups.
The hydrophobic aerogel particles used in the present invention exhibit a specific
surface per unit of weight (Sw) ranging from 200 to 1500 m2/g, preferably from
600 to 1200 m2/g and better still from 600 to 800 m2/g, and a size, expressed as
volume-average diameter (D[0.5]), of less than 1500 miti and preferably ranging
from 1 to 30 miti , more preferably from 5 to 25 miti , better still from 5 to 20 miti and
even better still from 5 to 15 miti .
According to an advantageous embodiment, the hydrophobic aerogel particles
used in the present invention have an oil absorption capacity, measured at the
wet point, ranging from 5 to 18 ml/g, preferably from 6 to 15 ml/g and better still
from 8 to 12 ml/g.
The absorption capacity measured at the wet point, denoted Wp, corresponds to
the amount of oil which it is necessary to add to 100 g of particles in order to
obtain a homogeneous paste.
It is measured according to the "wet point" method or method for determining the
oil uptake of a powder described in Standard NF T 30-022. It corresponds to the
amount of oil adsorbed onto the available surface of the powder and/or absorbed
by the powder by measurement of the wet point, described below:
An amount w = 2 g of powder is placed on a glass plate and then the oil (isononyl
isononanoate) is added dropwise. After addition of 4 to 5 drops of oil to the
powder, mixing is carried out using a spatula, and addition of oil is continued until
conglomerates of oil and powder have formed. From this point, the oil is added at
the rate of one drop at a time and the mixture is subsequently triturated with the
spatula. The addition of oil is stopped when a firm and smooth paste is obtained.
This paste must be able to be spread over the glass plate without cracks or the
formation of lumps. The volume Vs (expressed in ml) of oil used is then noted.
The oil uptake corresponds to the ratio Vs/w.
The aerogel particles of hydrophobic silica used according to the present
invention are preferably aerogel particles of silylated silica (INCI name: silica
silylate).
The preparation of aerogel particles of hydrophobic silica modified at the surface
by silylation is further described in the document US 7 470 725.
Use will in particular be made of aerogel particles of hydrophobic silica modified at
the surface with trimethylsilyl groups.
The hydrophobic aerogel particles which can be used in the present invention
advantageously exhibit a size, expressed as average diameter (D[0.5]), of less
than 1500 miti and preferably ranging from 1 to 30 miti , preferably from 5 to 25 miti ,
better still from 5 to 20 miti and even better still from 5 to 15 miti .
The specific surface per unit of weight can be determined by the nitrogen
absorption method, known as the BET (Brunauer-Emmett-Teller) method,
described in The Journal of the American Chemical Society, Vol. 60, page 309,
February 1938, which corresponds to International Standard ISO 5794/1
(appendix D). The BET specific surface corresponds to the total specific surface
of the particles under consideration.
The sizes of the aerogel particles according to the invention can be measured by
static light scattering using a commercial particle size analyser of MasterSizer
2000 type from Malvern. The data are processed on the basis of the Mie
scattering theory. This theory, which is exact for isotropic particles, makes it
possible to determine, in the case of non-spherical particles, an "effective" particle
diameter. This theory is described in particular in the publication by Van de Hulst,
H.C., "Light Scattering by Small Particles", Chapters 9 and 10, Wiley, New York,
1957.
According to an advantageous embodiment, the hydrophobic aerogel particles
used in the present invention exhibit a specific surface per unit of weight (Sw)
ranging from 600 to 800 m2/g and a size, expressed as volume-average diameter
(D[0.5]), ranging from 5 to 20 miti and better still from 5 to 15 miti .
The hydrophobic aerogel particles used in the present invention can
advantageously exhibit a packed density p ranging from 0.04 g/cm3 to 0.1 0 g/cm3
and preferably from 0.05 g/cm3 to 0.08 g/cm3.
In the context of the present invention, this density can be assessed according to
the following protocol, known as packed density protocol:
40 g of powder are poured into a graduated measuring cylinder and then the
measuring cylinder is placed on a Stav 2003 device from Stampf Volumeter. The
measuring cylinder is subsequently subjected to a series of 2500 packing actions
(this operation is repeated until the difference in volume between two consecutive
tests is less than 2%) and then the final volume Vf of packed powder is measured
directly on the measuring cylinder.
The packed density is determined by the ratio weight(w)/Vf, in the case in point
40/Vf (Vf being expressed in cm3 and w in g).
According to one embodiment, the hydrophobic aerogel particles used in the
present invention exhibit a specific surface per unit of volume Sv ranging from 5 to
60 m2/cm3, preferably from 10 to 50 m2/cm3 and better still from 15 to 40 m2/cm3.
The specific surface per unit of volume is given by the relationship:
Sv = Sw*p, where p is the packed density, expressed in g/cm3, and Sw is the
specific surface per unit of weight, expressed in m2/g, as defined above.
Mention may be made, as hydrophobic silica aerogels which can be used in the
invention, for example, of the aerogel sold under the name VM-2260 (INCI name:
Silica silylate) by Dow Corning, the particles of which exhibit an average size of
approximately 1000 microns and a specific surface per unit of weight ranging from
600 to 800 rrr/g.
Mention may also be made of the aerogels sold by Cabot under the references
Aerogel TLD 201 , Aerogel OGD 201 and Aerogel TLD 203, Enova Aerogel MT
1100 and Enova Aerogel MT 1200.
Use will more particularly be made of the aerogel sold under the name VM-2270
(INCI name: Silica silylate) by Dow Corning, the particles of which exhibit an
average size ranging from 5 to 15 microns and a specific surface per unit of
weight ranging from 600 to 800 m2/g.
The silica aerogel particles in accordance with the invention are preferably
present in the cosmetic composition in an amount of active material ranging from
0.5% to 15% by weight and more preferentially from 1% to 10% by weight relative
to the total weight of the composition.
PARTICULATE PHASE
The pulverulent phase according to the present invention preferably comprises at
least one additional filler, that is to say, in addition to the aerogel particles of
hydrophobic silica, the composition preferably comprises at least one filler other
than the aerogel particles.
As specified above, the solid composition according to the invention comprises a
pulverulent phase preferably at a content of greater than or equal to 15% by
weight, in particular of greater than or equal to 40% by weight and more
particularly ranging from 50% to 99.9% by weight, with respect to the total weight
of the said composition.
Within the meaning of the present invention, this pulverulent phase is formed of
any particulate solid material present in the composition and in particular fillers
and/or colorants, such as, for example, pigments.
Thus, the pulverulent phase comprises, in addition to the aerogel particles of
hydrophobic silica, at least one additional filler and optionally at least one colorant.
Additional fillers
The term "fillers" should be understood as meaning colourless or white and
inorganic or synthetic particles of any shape which are insoluble and dispersed in
the medium of the composition, whatever the temperature at which the
composition is manufactured.
Inorganic or organic in nature, they make it possible to confer, on the composition,
softness, mattness and uniformity on the skin.
The additional fillers used in the compositions according to the present invention
can be in lamellar (or platelet) form, in spherical (or globular) form, in the form of
fibres or in any other intermediate form between these defined forms.
In the present patent application, the term "spherical particles" is understood to
mean particles which have the shape or substantially the shape of a sphere and
which are insoluble in the medium of the composition according to the invention,
even at the melting point of the medium (approximately 00°C).
In addition, the term "lamellar particles" is understood here to mean particles of
parallelepipedal shape (rectangular or square surface), discoid shape (circular
surface) or ellipsoid shape (oval surface) characterized by three dimensions: a
length, a width and a height, which particles are insoluble in the medium of the
composition according to the invention, even at the melting point of the medium
(approximately 00°C).
According to a particularly preferred form of the invention, the pulverulent phase
comprises, as additional fillers, a mixture of spherical particles and lamellar
particles.
Spherical particles
The spherical particles used according to the invention have the shape or
substantially the shape of a sphere and can be hollow or solid. Advantageously,
the particles of the invention have a particle size (number-average diameter)
ranging from 0.1 miti to 250 miti , better still ranging from 1 miti to 150 miti and
better still from 10 miti to 100 miti .
The spherical particles can be organic or inorganic microspheres. Mention may be
made, as spherical organic powders, for example, of polyamide powders and in
particular Nylon® powders, such as Nylon-1 or Polyamide 12, sold under the
Orgasol names by Atochem; polyethylene powders; polytetrafluoroethylene
(Teflon®) powders; microspheres based on acrylic copolymers, such as those
made of ethylene glycol dimethacrylate/lauryl methacrylate copolymer sold by
Dow Corning under the Polytrap name; expanded powders, such as hollow
microspheres and in particular the microspheres sold under the Expancel name
by Kemanord Plast or under the name Micropearl F 80 ED by Matsumoto; silicone
resin microbeads, such as those sold under the Tospearl name by Toshiba
Silicone; polymethyl methacrylate microspheres, sold under the name
Microsphere M-1 00 by Matsumoto or under the name Covabead LH85 by
Wackherr; ethylene/acrylate copolymer powders, such as those sold under the
Flobeads name by Sumitomo Seika Chemicals; powders formed of natural
organic materials, such as starch powders, in particular powders formed of maize,
wheat or rice starch, which are or are not crossi inked, such as powders formed of
starch crosslinked with octenylsuccinic anhydride, sold under the Dry-Flo name by
National Starch; metal soaps derived from organic carboxylic acids having from 8
to 22 carbon atoms, preferably from 12 to 18 carbon atoms, for example zinc
stearate, magnesium stearate, lithium stearate, zinc laurate or magnesium
myristate; Polypore® L 200 (Chemdal Corporation); silicone resin microbeads
(Tospearl ® from Toshiba, for example); polyurethane powders, in particular
powders formed of crosslinked polyurethane comprising a copolymer, the said
copolymer comprising trimethylol hexyllactone, such as the hexamethylene
diisocyanate/trimethylol hexyllactone polymer sold under the name Plastic Powder
D-400® or Plastic Powder D-800® by Toshiki; carnauba microwaxes, such as that
sold under the name MicroCare 350® by Micro Powders; synthetic wax
microwaxes, such as that sold under the name MicroEase 114S® by Micro
Powders; microwaxes composed of a mixture of carnauba wax and polyethylene
wax, such as those sold under the names Micro Care 300® and 3 10® by Micro
Powders; microwaxes consisting of a mixture of carnauba wax and synthetic wax,
such as that sold under the name Micro Care 325® by Micro Powders; or
polyethylene microwaxes, such as those sold under the names Micropoly 200®,
220®, 220L® and 250S® by Micro Powders.
According to a particularly preferred embodiment of the present invention, the
spherical particles will be chosen from polyamide powders, polymethyl
methacrylate microspheres, polytetrafluoroethylene powders and their mixtures.
These spherical particles can be present in amounts preferably ranging from 20%
to 100% by weight, more preferentially from 20% to 50% by weight and more
particularly from 25% to 35% by weight, with respect to the total weight of the
mixture of spherical particles and lamellar particles.
Lamellar particles
As indicated above, lamellar particles are particles of parallelepipedal shape
(rectangular or square surface), discoid shape (circular surface) or ellipsoid shape
(oval surface), characterized by three dimensions: a length, a width and a height.
When the shape is circular, the length and the width are identical and correspond
to the diameter of a disc, whereas the height corresponds to the thickness of the
disc. When the surface is oval, the length and the width correspond, respectively,
to the large axis and the small axis of an ellipse and the height corresponds to the
thickness of the elliptic disc formed by the platelet. When it is a parallelepiped, the
length and the width can be of identical or different dimensions: when they are of
the same dimension, the shape of the surface of the parallelepiped is square; in
the contrary case, the shape is rectangular. With regard to the height, it
corresponds to the thickness of the parallelepiped.
The length of the lamellar particles used according to the invention preferably
ranges from 0.01 to 100 miti , better still from 0.1 to 50 miti and even better still
from 1 to 50 miti . The width of these platelets preferably ranges from 0.01 to 100
miti , better still from 0.1 to 50 miti and even better still from 1 to 10 miti . The height
(thickness) of these platelets preferably ranges from 0.1 nm to 1 miti (0.1 to 1000
nm), better still from 1 nm to 600 nm and even better still from 1 nm to 500 nm.
Mention may be made, as lamellar particles which can be used in the composition
of the invention, of lamellar silicates.
Mention may be made, as lamellar silicates, of talcs, micas, perlites and their
mixtures.
Talcs are hydrated magnesium silicates usually comprising aluminium silicate.
The crystal structure of talc consists of repeated layers of a sandwich of brucite
between layers of silica.
Micas are aluminium silicates optionally comprising iron and/or alkali metals. They
have the property of being able to split up into thin layers (approximately 1 miti ) .
They generally have a dimension ranging from 5 to 150 miti , preferably from 10 to
100 miti and better still from 10 to 60 miti for the largest dimension (length) and a
height (thickness) of from 0.1 to 0.5 miti . Mention may be made, as micas, of
phlogopite, muscovite, fluorophlogopite, vermiculite and their mixtures.
Mention may also be made, among lamellar silicates, of perlites and preferably
expanded perlites.
The perlites which can be used according to the invention are generally
aluminosilicates of volcanic origin and have the composition:
70.0-75.0% by weight of silica SiO2
12.0-1 5.0% by weight of aluminium oxide AI2O3
3.0-5.0% of sodium oxide Na2O
3.0-5.0% of potassium oxide K2O
0.5-2% of iron oxide Fe2O3 -
0.2-0.7% of magnesium oxide MgO
0.5-1 .5% of calcium oxide CaO
0.05-0.15% of titanium oxide TiO2
The perlite is ground, dried and then calibrated in a first stage. The product
obtained, known as perlite ore, is grey-coloured and has a size of the order of 100
miti .
The perlite ore is subsequently expanded (1000°C/2 seconds) to give more or
less white particles. When the temperature reaches 850-900°C, the water trapped
in the structure of the material evaporates and brings about the expansion of the
material, with respect to its original volume. The expanded perlite particles in
accordance with the invention may be obtained via the expansion process
described in Patent US 5 002 698.
Preferably, the perlite particles used will be ground; in this case, they are known
as Expanded Milled Perlite (EMP). They preferably have a particle size defined by
a median diameter D50 ranging from 0.5 to 50 miti and preferably from 0.5 to 40
miti .
Preferably, the perlite particles used exhibit a loose bulk density at 25°C ranging
from 10 to 400 kg/m3 (Standard DIN 53468) and preferably from 10 to 300 kg/m3.
Preferably, the expanded perlite particles according to the invention have a water
absorption capacity, measured at the wet point, ranging from 200% to 500% and
preferably from 250% to 800%.
The wet point corresponds to the amount of water which has to be added to 1 g of
particle in order to obtain a homogeneous paste. This method derives directly
from the oil uptake method applied to solvents. The measurements are carried out
in the same way via the wet point and the flow point, which have, respectively, the
following definitions:
wet point: weight, expressed in grams per 100 g of product, corresponding to the
production of a homogeneous paste during the addition of a solvent to a powder;
flow point: weight, expressed in grams per 100 g of product, at and above which
the amount of solvent is greater than the ability of the powder to retain it. This is
reflected by the production of a more or less homogeneous mixture which flows
over the glass plate.
The wet point and the flow point are measured according to the following protocol:
According to a particularly preferred embodiment of the present invention, the
lamellar particles will be chosen from an expanded perlite, a talc, a mica and their
mixtures.
Advantageously, use is more particularly made, in the composition of the
invention, as lamellar particles, of talc, such as the products sold under the names
Rose Talc and Talc SG-2000 by Nippon Talc; mica, such as the products sold
under the names Mica M RP and Silk Mica by the company Merck; titanium oxidecoated
micas, such as mica/titanium oxide/brown iron oxide (CTFA name:
Mica/Iron oxides/Titanium dioxide), sold under the name Cloisonne Rouge
Flambe 440 X by Engelhard; or expanded perlite (INCI name: Expanded Milled
Perlite), as sold under the name Optimat 1430 OR by World Minerals.
These lamellar particles can be present in amounts preferably ranging from 40%
to 100% by weight, more preferentially from 50% to 9 1% by weight and better still
from 60% to 80% by weight, with respect to the total weight of the mixture of
spherical particles and lamellar particles.
Mention may also be made, among the additional fillers which can be present in
the pulverulent phase of the composition, of fibres, such as fibres of synthetic or
natural and inorganic or organic origin. They can be short or long, individual or
organized, for example braided, and hollow or solid. They can have any shape
and can in particular be circular or polygonal (square, hexagonal or octagonal) in
cross section, depending on the specific application envisaged. In particular, their
ends are blunted and/or polished to prevent injury. The fibres have a length
ranging from 1 m to 10 mm, preferably from 0.1 mm to 5 mm and better still from
0.3 mm to 3 mm. Their cross section may be included in a circle with a diameter
ranging from 2 nm to 500 miti , preferably ranging from 100 nm to 100 miti and
better still ranging from 1 miti to 50 miti . Mention may be made, as fibres which
can be used in the compositions according to the invention, of non-rigid fibres,
such as polyamide fibres, such as in particular Nylon (or Polyamide 6) (INCI
name: Nylon 6) fibres or Nylon 6,6 (or Polyamide 66) (INCI name: Nylon 66)
fibres, or rigid fibres, such as polyimide/amide fibres, for example those sold
under the Kermel® or Kermel Tech® names by Rhodia, or poly(p-phenylene
terephthalamide) (or aramid) fibres, sold in particular under the Kevlar ® name by
DuPont de Nemours, and their mixtures.
The pulverulent phase can additionally comprise colouring agents.
Colouring agent(s)
The compositions according to the invention can also comprise colouring agents.
The colouring agent(s) or colorant(s) according to the invention is (or are)
preferably chosen from pigments, pearlescent agents, water-soluble or fat-soluble
dyes, and their mixtures.
Pigments
The term "pigments" should be understood as meaning white or coloured and
inorganic or organic particles of any shape which are insoluble in the physiological
medium and which are intended to colour the composition.
The pigments can be white or coloured and inorganic and/or organic.
Mention may be made, among the inorganic pigments, of titanium dioxide,
optionally surface-treated, zirconium oxide or cerium oxide, and also zinc oxide,
iron (black, yellow or red) oxide or chromium oxide, manganese violet, ultramarine
blue, chromium hydrate and ferric blue, and metal powders, such as aluminium
powder or copper powder.
The organic pigments can be chosen from the materials below and their mixtures:
cochineal carmine,
organic pigments of azo dyes, anthraquinone dyes, indigoid dyes, xanthene dyes,
pyrene dyes, quinoline dyes, triphenylmethane dyes o fluoran dyes.
Mention may in particular be made, among the organic pigments, of the D&C
certified pigments known under the following names: D&C Blue No. 4, D&C Brown
No. 1, D&C Green No. 5, D&C Green No. 6, D&C Orange No. 4, D&C Orange No.
5, D&C Orange No. 10, D&C Orange No. 11, D&C Red No. 6, D&C Red No. 7,
D&C Red No. 17, D&C Red No. 2 1, D&C Red No. 22, D&C Red No. 27, D&C Red
No. 28, D&C Red No. 30, D&C Red No. 3 1, D&C Red No. 33, D&C Red No. 34,
D&C Red No. 36, D&C Violet No. 2, D&C Yellow No. 7, D&C Yellow No. 8, D&C
Yellow No. 10, D&C Yellow No. 11, FD&C Blue No. 1, FD&C Green No. 3, FD&C
Red No. 40, FD&C Yellow No. 5 or FD&C Yellow No. 6 .
The chemical substances corresponding to each of the organic colorants cited
above are mentioned in the publication "International Cosmetic Ingredient
Dictionary and Handbook", 1997 edition, pages 371 to 386 and 524 to 528,
published by The Cosmetic, Toiletries and Fragrance Association, the content of
which is incorporated into the present patent application by reference.
A composition according to the invention can comprise a content of pigments
ranging from 0% to 30% by weight, with respect to the total weight of the
composition, preferably ranging from 2% to 20% by weight and preferentially
ranging from 4% to 10% by weight, with respect to the total weight of the
composition.
Pearlescent agents
The term "pearlescent agents" should be understood as meaning coloured
particles of any shape, which are or are not iridescent, produced in particular by
certain molluscs in their shells or else synthesized, and which exhibit a colour
effect via optical interference.
Mention may be made, as examples of pearlescent agents, of pearlescent
pigments, such as titanium oxide-coated mica covered with an iron oxide, mica
covered with bismuth oxychloride or titanium oxide-coated mica covered with
chromium oxide, or pearlescent pigments based on bismuth oxychloride. They
can also be mica particles, at the surface of which are superimposed at least two
successive layers of metal oxides and/or of organic colorants.
The compositions according to the invention can comprise a content of
pearlescent agents ranging from 0% to 30% by weight, for example from 0.01 % to
5% by weight, with respect to the total weight of the composition.
In addition to the fillers and pigments, the particulate phase of the invention can
comprise water-soluble or fat-soluble dyes.
The term "fat-soluble dyes" should be understood as meaning compounds,
generally organic, which are soluble in fatty substances, such as oils.
The fat-soluble dyes are, for example, Sudan red, D&C Red No. 17, D&C Green
No. 6, b-carotene, soybean oil, Sudan brown, D&C Yellow No. 11, D&C Violet No.
2, D&C Orange No. 5, quinoline yellow, annatto or bromo acids.
Within the meaning of the invention, the term "water-soluble dye" is understood to
mean any natural or synthetic compound, generally organic, which is soluble in an
aqueous phase or in water-miscible solvents and which is suitable for colouring.
Mention may in particular be made, as water-soluble dyes suitable for the
invention, of synthetic or natural water-soluble dyes, such as, for example, FDC
Red 4, DC Red 6, DC Red 22, DC Red 28, DC Red 30, DC Red 33, DC Orange 4,
DC Yellow 5, DC Yellow 6, DC Yellow 8, FDC Green 3, DC Green 5, FDC Blue 1,
betanin (beetroot), carmine, copper chlorophyllin, methylene blue, anthocyanins
(oenocyanin, black carrot, hibiscus, elder), caramel and riboflavin.
LIQUID FATTY PHASE
According to a specific form of the invention, the compositions in accordance with
the invention can comprise at least one liquid fatty phase.
This fatty phase can advantageously be used as binder in the said pulverulent
phase.
The term "liquid" is understood to mean liquid at room temperature (25°C) and
atmospheric pressure (760 mmHg).
The liquid fatty phase generally comprises, in addition to the lipophilic UV
screening agent or agents, at least one volatile or non-volatile hydrocarbon oil
and/or one volatile or non-volatile silicone oil.
Within the meaning of the invention, the term "volatile oil" is understood to mean
an oil which is capable of evaporating on contact with the skin or the keratinous
fibre in less than one hour, at ambient temperature and atmospheric pressure.
The volatile oil(s) of the invention are volatile cosmetic oils which are liquid at
ambient temperature and which have a non-zero vapour pressure, at ambient
temperature and atmospheric pressure, ranging in particular from 0.1 3 Pa to 40
000 Pa ( 10 3 to 300 mmHg), in particular ranging from 1.3 Pa to 13 000 Pa (0.01
to 100 mmHg) and more particularly ranging from 1.3 Pa to 1300 Pa (0.01 to 10
mmHg).
The term "non-volatile oil" is understood to mean an oil which remains on the
skin or the keratinous fibre, at ambient temperature and atmospheric pressure,
for at least several hours and which has in particular a vapour pressure of less
than 10 3 mmHg (0.13 Pa).
a) Hydrocarbon oils
Mention may in particular be made, as non-volatile hydrocarbon oils which can
be used according to the invention, of:
(i) hydrocarbon oils of vegetable origin, such as glyceride triesters, which are
generally triesters of fatty acids and of glycerol, the fatty acids of which can
have varied chain lengths from C4 to C 24 , it being possible for these chains to be
saturated or unsaturated and linear or branched; these oils are in particular
wheat germ oil, sunflower oil, grape seed oil, sesame oil, maize oil, apricot oil,
castor oil, shea oil, avocado oil, olive oil, soybean oil, sweet almond oil, palm oil,
rapeseed oil, cottonseed oil, hazelnut oil, macadamia oil, jojoba oil, alfalfa oil,
poppy oil, pumpkinseed oil, cucumber oil, blackcurrant oil, evening primrose oil,
millet oil, barley oil, quinoa oil, rye oil, safflower oil, candlenut oil, passionflower
oil and musk rose oil; or else caprylic/capric acid triglycerides, such as those
sold by Stearineries Dubois or those sold under the names Miglyol 810, 8 12 and
8 18 by Dynamit Nobel,
(ii) synthetic ethers having from 10 to 40 carbon atoms;
(iii) linear or branched hydrocarbons of mineral or synthetic origin, such as
petrolatum, polydecenes, hydrogenated polyisobutene, such as Parleam,
squalane and their mixtures;
(iv) synthetic esters, such as the oils of formula RCOOR' in which R represents
the residue of a linear or branched fatty acid comprising from 1 to 40 carbon
atoms and R' represents a hydrocarbon chain, in particular a branched
hydrocarbon chain, comprising from 1 to 40 carbon atoms, provided that R + R' >
10, such as, for example, purcellin oil (cetearyl octanoate), isopropyl myristate,
isopropyl palmitate, C12-C15 alkyl benzoate, such as the product sold under the
trade name Finsolv TN or Witconol TN by Witco or Tegosoft TN by Evonik
Goldschmidt, 2-ethylphenyl benzoate, such as the commercial product sold under
the name X-Tend 226 by ISP, isopropyl lanolate, hexyl laurate, diisopropyl
adipate, isononyl isononanoate, oleyl erucate, 2-ethylhexyl palmitate, isostearyl
isostearate, alcohol or polyalcohol octanoates, decanoates or ricinoleates, such
as propylene glycol dioctanoate; hydroxylated esters, such as isostearyl lactate or
diisostearyl malate; and pentaerythritol esters; citrates or tartrates, such as linear
d i(Ci2-Ci 3 alkyl) tartrates, such as those sold under the name Cosmacol ETI by
Enichem Augusta Industriale, and also linear d i(Ci4-Ci 5 alkyl) tartrates, such as
those sold under the name Cosmacol ETL by the same company; acetates;
(v) fatty alcohols which are liquid at ambient temperature and which have a
branched and/or unsaturated carbon chain comprising from 12 to 26 carbon
atoms, such as octyldodecanol, isostearyl alcohol, oleyl alcohol, 2-hexyldecanol,
2-butyloctanol or 2-undecylpentadecanol;
(vi) higher fatty acids, such as oleic acid, linoleic acid or linolenic acid;
(vii) carbonates, such as dicaprylyl carbonate, such as the product sold under
the name Cetiol CC by Cognis;
(viii) fatty amides, such as isopropyl N-lauroyl sarcosinate, such as the product
sold under the trade name Eldew SL205 from Ajinomoto;
and their mixtures.
Mention may in particular be made, as volatile hydrocarbon oils which can be
used according to the invention, of hydrocarbon oils having from 8 to 16 carbon
atoms, in particular branched Cs-Ci6 alkanes, such as Cs-Ci6 isoalkanes of
petroleum origin (also known as isoparaffins), such as isododecane (also known
as 2,2,4,4,6-pentamethylheptane), isodecane or isohexadecane, or the alkanes
described in the patent applications from Cognis, WO 2007/068371 or WO
2008/1 55059 (mixtures of different alkanes differing by at least one carbon).
These alkanes are obtained from fatty alcohols, themselves obtained from
coconut oil or palm oil, the oils sold under the Isopar or Permethyl trade names,
branched Cs-Ci6 esters, isohexyl neopentanoate and their mixtures.
Other volatile hydrocarbon oils, such as petroleum distillates, in particular those
sold under the name Shell Solt by Shell, can also be used. According to one
embodiment, the volatile solvent is chosen from volatile hydrocarbon oils having
from 8 to 16 carbon atoms and their mixtures.
b) Silicone oils
The non-volatile silicone oils can be chosen in particular from non-volatile
polydimethylsiloxanes (PDMSs), polydimethylsiloxanes comprising alkyl or
alkoxy groups which are pendent and/or at the end of the silicone chain, which
groups each have from 2 to 24 carbon atoms, or phenylated silicones, such as
phenyl trimethicones, phenyl dimethicones,
phenyl(trimethylsiloxy)diphenylsiloxanes, diphenyl dimethicones,
diphenyl(methyldiphenyl)trisiloxanes or (2-phenyletnyl)trimethylsiloxysilicates.
Mention may be made, as volatile silicone oils, for example, of volatile linear or
cyclic silicone oils, in particular those having a viscosity < 8 centistokes
(8x1 0 6 m2/s) and having in particular from 2 to 7 silicon atoms, these silicones
optionally comprising alkyl or alkoxy groups having from 1 to 10 carbon atoms.
Mention may in particular be made, as volatile silicone oil which can be used in
the invention, of octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane,
dodecamethylcyclohexasiloxane, heptamethylhexyltrisiloxane,
heptamethyloctyltrisiloxane, hexamethyldisiloxane, octamethyltrisiloxane,
decamethyltetrasiloxane, dodecamethylpentasiloxane and their mixtures.
Mention may also be made of volatile linear alkyltrisiloxane oils of general
formula (I):
where R represents an alkyl group comprising from 2 to 4 carbon atoms, one or
more hydrogen atoms of which can be replaced by a fluorine or chlorine atom.
Mention may be made, among the oils of general formula (I), of:
3-butyl-1 , 1 , 1 ,3,5,5,5-heptamethyltrisiloxane,
3-propyl-1 , 1 , 1 ,3,5,5,5-heptamethyltrisiloxane, and
3-ethyl-1 , 1 , 1 ,3,5,5,5-heptamethyltrisiloxane,
corresponding to the oils of formula (I) for which R is respectively a butyl group,
a propyl group or an ethyl group.
According to a specific embodiment, the liquid fatty phase can comprise one or
more liquid lipophilic screening agents and in particular can consist solely of the
said liquid lipophilic UV screening agent or agents.
The term "liquid" is understood to mean liquid at room temperature (25°C) and
atmospheric pressure (760 mmHg).
The liquid fatty phase preferably varies from 0.1 % to 85% by weight and
preferably from 5% to 50% by weight, with respect to the total weight of the
composition.
LIPOPHILIC ORGANIC SCREENING AGENTS
The lipophilic organic UV screening agents are chosen in particular from cinnamic
derivatives; anthranilates; salicylic derivatives; dibenzoylmethane derivatives,
camphor derivatives; benzophenone derivatives; b,b-diphenylacrylate derivatives;
triazine derivatives; benzotriazole derivatives; benzalmalonate derivatives, in
particular those mentioned in Patent US 5 624 663; imidazolines; p-aminobenzoic
acid (PABA) derivatives; benzoxazole derivatives, such as described in Patent
Applications EP 0 832 642, EP 1 027 883, EP 1 300 137 and DE 101 62 844;
screening polymers and screening silicones, such as those described in particular
in Patent Application WO 93/04665; dimers derived from c -alkylstyrene, such as
those described in Patent Application DE 198 55 649; 4,4-diarylbutadienes, such
as described in Patent Applications EP 0 967 200, DE 197 46 654, DE 197 55
649, EP-A-1 008 586, EP 1 133 980 and EP 133 981 ; merocyanine derivatives,
such as those described in Patent Applications WO 04/006 878, WO 05/058 269,
WO 06/032 741 , FR 2 957 249 and FR 2 957 250; and their mixtures.
Mention may be made, as examples of additional organic photoprotective agents,
of those denoted hereinbelow under their INCI names:
Mention may be made, as examples of lipophilic organic UV screening agents, of
those denoted hereinbelow under their INCI names:
Dibenzoylmethane derivatives:
Butyl Methoxy Dibenzoylmethane or avobenzone, provided for sale under the
trade name Parsol 1789 by DSM Nutritional Products,
para-Am inobenzoic acid derivatives:
PABA,
Ethyl PABA,
Ethyl Dihydroxypropyl PABA,
Ethylhexyl Dimethyl PABA, sold in particular under the name Escalol 507 by ISP,
Salicylic derivatives:
Homosalate, sold under the name Eusolex HMS by Rona/EM Industries,
Ethylhexyl Salicylate, sold under the name Neo Heliopan OS by Symrise,
Cinnamic derivatives:
Ethylhexyl Methoxycinnamate, sold in particular under the trade name Parsol
MCX by DSM Nutritional Products,
Isopropyl Methoxycinnamate,
Isoamyl Methoxycinnamate, sold under the trade name Neo Heliopan E 1000 by
Symrise,
Cinoxate,
Diisopropyl Methylcinnamate,
b,b-Diphenylacrylate derivatives:
Octocrylene, sold in particular under the trade name Uvinul N539 by BASF,
Etocrylene, sold in particular under the trade name Uvinul N35 by BASF,
Benzophenone derivatives:
Benzophenone-1 , sold under the trade name Uvinul 400 by BASF,
Benzophenone-2, sold under the trade name Uvinul D50 by BASF,
Benzophenone-3 or Oxybenzone, sold under the trade name Uvinul M40 by
BASF,
Benzophenone-6, sold under the trade name Helisorb by Norquay,
Benzophenone-8, sold under the trade name Spectra-Sorb UV-24 by American
Cyanamid,
Benzophenone-1 2,
n-Hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate, sold under the trade name
Uvinul A+ or, in the form of a mixture with octyl methoxycinnamate, under the
trade name Uvinul A+B by BASF,
, 1 '-( ,4-Piperazinediyl)bis[1 -[2-[4-(diethylamino)-2-
hydroxybenzoyl]phenyl]methanone (CAS 919803-06-8), in its micronized or nonmicron
ized form,
Benzyl idenecamphor derivatives:
3-Benzylidene Camphor, manufactured under the name Mexoryl SD by Chimex,
4-Methylbenzylidene Camphor, sold under the name Eusolex 6300 by Merck,
Polyacrylamidomethyl Benzylidene Camphor, manufactured under the name
Mexoryl SW by Chimex,
Phenylbenzotriazole derivatives:
Drometrizole Trisiloxane, sold under the name Silatrizole by Rhodia Chimie,
Triazine derivatives:
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, sold under the trade name
Tinosorb S by BASF,
Ethylhexyl Triazone, sold in particular under the trade name Uvinul T 150 by
BASF,
Diethylhexyl Butamido Triazone, sold under the trade name Uvasorb HEB by
Sigma 3V,
2,4,6-Tris(dineopentyl 4'-aminobenzalmalonate)-s-triazine,
2,4,6-Tris(diisobutyl 4'-aminobenzalmalonate)-s-triazine,
2,4-Bis(dineopentyl 4'-aminobenzalmalonate)-6-(n-butyl 4'-aminobenzoate)-striazine,
Anthranilic derivatives:
Menthyl Anthranilate, sold under the trade name Neo Heliopan MA by Symrise,
Imidazoline derivatives:
Ethylhexyl Dimethoxybenzylidene Dioxoimidazoline Propionate,
Benzalmalonate derivatives:
Dineopentyl 4'-methoxybenzalmalonate,
Polyorganosiloxane comprising benzalmalonate functional groups, such as
Polysilicone-1 5, sold under the trade name Parsol SLX by DSM,
4,4-Diarylbutadiene derivatives:
1, 1 -Dicarboxy(2,2'-dimethylpropyl)-4,4-diphenylbutadiene,
Benzoxazole derivatives:
2,4-Bis[4-[5-(1 , 1 -dimethylpropyl)benzoxazol-2-yl]phenylimino]-6-[(2-
ethylhexyl)imino]-1 ,3,5-triazine, sold under the name Uvasorb K2A by Sigma 3V,
and their mixtures.
Lipophilic merocvanine derivatives:
- Octyl 5-N,N-diethylamino-2-phenylsulfonyl-2,4-pentadienoate
and their mixtures.
The preferred lipophilic or insoluble organic screening agents are chosen from:
Butyl Methoxy Dibenzoylmethane,
Ethylhexyl Methoxycinnamate,
Ethylhexyl Salicylate,
Homosalate,
Butyl Methoxy Dibenzoylmethane,
Octocrylene,
Benzophenone-3,
n-Hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate,
4-Methylbenzylidene Camphor,
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine,
Ethylhexyl Triazone,
Diethylhexyl Butamido Triazone,
2,4,6-Tris(dineopentyl 4'-aminobenzalmalonate)-s-triazine,
2,4,6-Tris(diisobutyl 4'-aminobenzalmalonate)-s-triazine,
2,4-Bis(dineopentyl 4'-aminobenzalmalonate)-6-(n-butyl 4'-aminobenzoate)-striazine,
2,4,6-Tris(biphenyl-4-yl)-1 ,3,5-triazine,
2,4,6-Tris(terphenyl)-1 ,3,5-triazine,
Drometrizole Trisiloxane
Polysilicone-1 5,
1, 1 -Dicarboxy(2,2'-dimethylpropyl)-4,4-diphenylbutadiene,
2,4-Bis[4-[5-(1 , 1 -dimethylpropyl)benzoxazol-2-yl]phenylimino]-6-[(2-
ethylhexyl)imino]-1 ,3,5-triazine,
and mixtures thereof.
The preferred lipophilic organic screening agents are more particularly chosen
from:
Butyl Methoxy Dibenzoylmethane,
Octocrylene,
Ethylhexyl Salicylate,
n-Hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate,
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine,
Ethylhexyl Triazone,
Diethylhexyl Butamido Triazone,
Drometrizole Trisiloxane, and their mixtures.
The lipophilic organic UV screening agent or agents are preferably present in the
compositions according to the invention at a content ranging from 0.1 % to 40% by
weight and in particular from 5% to 25% by weight, with respect to the total weight
of the composition.
POLYOLS
According to a specific form of the invention, the solid anhydrous composition
according to the invention comprises at least one C2-C32 polyol.
This compound is particularly advantageous for conferring an affinity for water on
the solid anhydrous composition in which it is present.
The term "polyol" should be understood as meaning, within the meaning of the
present invention, any organic molecule comprising at least two free hydroxyl
groups.
Preferably, a polyol in accordance with the present invention is present in liquid
form at ambient temperature.
A polyol suitable for the invention can be a compound of saturated or unsaturated
and linear, branched or cyclic alkyl type carrying, on the alkyl chain, at least
two -OH functional groups, in particular at least three -OH functional groups and
more particularly at least four -OH functional groups.
The polyols advantageously suitable for the formulation of a composition
according to the present invention are those exhibiting in particular from 2 to 32
carbon atoms and preferably from 3 to 16 carbon atoms.
Advantageously, the polyol can be chosen, for example, from ethylene glycol,
pentaerythritol, trimethylolpropane, propylene glycol, 1,3-propanediol, butylene
glycol, isoprene glycol, pentylene glycol, hexylene glycol, glycerol, polyglycerols,
such as glycerol oligomers, for example diglycerol, polyethylene glycols and their
mixtures.
According to a preferred embodiment of the invention, the said polyol is chosen
from ethylene glycol, pentaerythritol, trimethylolpropane, propylene glycol,
glycerol, polyglycerols, polyethylene glycols and their mixtures.
The polyol or polyols are preferably present in an amount ranging from 0.1 % to
20% by weight and better still from 0.1 % to 10% by weight, with respect to the
total weight of the said composition.
AQUEOUS PHASE
According to a specific form of the invention, the composition according to the
invention can comprise an aqueous phase.
This aqueous phase, when present, is employed in an amount compatible with the
pulverulent formulation form required according to the invention.
The aqueous phase can be a demineralized water or alternatively a floral water,
such as cornflower water, and/or a mineral water, such as Vittel water, Lucas
water or La Roche-Posay water, and/or a thermal water.
The aqueous phase can also comprise a polyol which is miscible with water at
ambient temperature (25°C) chosen in particular from polyols having in particular
from 2 to 20 carbon atoms, preferably having from 2 to 10 carbon atoms and
preferentially having from 2 to 6 carbon atoms, such as glycerol, propylene glycol,
butylene glycol, pentylene glycol, hexylene glycol, dipropylene glycol or diethylene
glycol; glycol ethers (in particular having from 3 to 16 carbon atoms), such as
mono-, di- or tripropylene glycol (Ci-C 4)alkyl ethers, mono-, di- or triethylene
glycol (Ci-C 4)alkyl ethers; and their mixtures.
The composition according to the invention can comprise a polyol which is
miscible with water at ambient temperature. Such polyols can promote the
moisturization of the skin surface on which the composition is applied.
In addition, the composition according to the invention can comprise a
monoalcohol comprising from 2 to 6 carbon atoms, such as ethanol or
isopropanol.
A composition according to the invention advantageously comprises less than 5%
by weight of aqueous phase and in particular of water, with respect to the total
weight of the composition. Preferentially, a composition according to the invention
is devoid of aqueous phase and in particular is devoid of water.
ADJUVANTS
The compositions in accordance with the present invention can additionally
comprise one or more conventional cosmetic adjuvants chosen from waxes,
thickeners, softeners, humectants, opacifiers, stabilizers, emollients, silicones,
fragrances, preservatives, active agents, polymers or any other ingredient
normally used in the cosmetics and/or dermatological fields.
Of course, a person skilled in the art will take care to choose the abovementioned
optional additional compound or compounds and/or their amounts so that the
advantageous properties intrinsically attached to the compositions in accordance
with the invention are not, or not substantially, detrimentally affected by the
envisaged addition or additions.
According to a specific form of the invention, the compositions according to the
invention can additionally comprise insoluble UV screening agents chosen from
insoluble organic UV screening agents, inorganic UV screening agents and
composite materials comprising an organic or inorganic matrix and at least one
inorganic UV screening agent.
INSOLUBLE UV SCREENING AGENTS
The term "insoluble UV screening agent" is understood to mean any UV screening
agent capable of being in the form of particles in a liquid fatty phase and in a liquid
aqueous phase.
The insoluble organic UV screening agent or agents are preferably present in the
compositions according to the invention at a content ranging from 0.1 % to 10% by
weight and in particular from 0.5% to 5% by weight, with respect to the total
weight of the composition.
Mention may be made, among insoluble organic screening agents, of those
described in Applications US 5 237 071 , US 5 166 355, GB 2 303 549, DE 197
26 184 and EP 893 119, in particular methylenebis[(hydroxyphenyl)benzotriazole]
derivatives, such as Methylene Bis-Benzotriazolyl Tetramethylbutylphenol, sold in
the solid form under the trade name Mixxim BB/100 by Fairmount Chemical or in
the micronized form in aqueous dispersion under the trade name Tinosorb M by
BASF.
Mention may also be made of the symmetrical triazine screening agents
described in Patent US 6 225 467, Application WO 2004/08541 2 (see
compounds 6 and 9) or the document "Symmetrical Triazine Derivatives", IP.COM
Journal, IP.COM INC, West Henrietta, NY, US (20 September 2004), in particular
2,4,6-tris(biphenyl)-1 ,3,5-triazines (in particular 2,4,6-tris(biphenyl-4-yl)-1 ,3,5-
triazine) and 2,4,6-tris(terphenyl)-1 ,3,5-triazine, which is also mentioned in
Beiersdorf Applications WO 06/035000, WO 06/034982, WO 06/034991 , WO
06/035007, WO 2006/034992 and WO 2006/034985.
Inorganic UV screening agents
The inorganic UV screening agents used in accordance with the present invention
are metal oxide pigments.
According to a specific form of the invention, the inorganic UV screening agents of
the invention are metal oxide particles having an average elementary particle size
of less than or equal to 0.5 miti , more preferably between 0.005 and 0.5 miti and
more preferably still between 0.01 and 0.1 miti , and preferably between 0.01 5 and
0.05 m.
The term "average size" of the particles is understood to mean the parameter
D[4,3] measured using a Mastersizer 2000 particle size analyser (Malvern). The
light intensity scattered by the particles as a function of the angle at which they
are illuminated is converted to size distribution according to the Mie theory. The
parameter D[4,3] is measured; this is the average diameter of the sphere having
the same volume as the particle. For a spherical particle, reference will often be
made to "average diameter".
The term "average elementary size" is understood to mean the size of nonaggregated
particles.
They can be chosen in particular from titanium, zinc, iron, zirconium or cerium
oxides, or their mixtures, and more particularly titanium oxides.
Such coated or non-coated metal oxide pigments are described in particular in
Patent Application EP-A-0 5 18 773. Mention may be made, as commercial
pigments, of the products sold by Kemira, Tayca, Merck and Degussa.
The metal oxide pigments can be coated or non-coated.
The coated pigments are pigments which have been subjected to one or more
surface treatments of chemical, electronic, mechanochemical and/or mechanical
nature with compounds such as amino acids, beeswax, fatty acids, fatty alcohols,
anionic surfactants, lecithins, sodium, potassium, zinc, iron or aluminium salts of
fatty acids, metal alkoxides (of titanium or aluminium), polyethylene, silicones,
proteins (collagen, elastin), alkanolamines, silicon oxides, metal oxides or sodium
hexametaphosphate.
The coated pigments are more particularly titanium oxides coated:
- with silica, such as the product Sunveil from Ikeda,
- with silica and iron oxide, such as the product Sunveil F from Ikeda,
- with silica and alumina, such as the products Microtitanium Dioxide MT 500 SA
and Microtitanium Dioxide MT 100 SA from Tayca or Tioveil from Tioxide,
- with alumina, such as the products Tipaque TTO-55 (B) and Tipaque TTO-55 (A)
from Ishihara and UVT 14/4 from Kemira,
- with alumina and aluminium stearate, such as the products Microtitanium
Dioxide MT 100 T, MT 100 TX, MT 100 Z and MT-01 from Tayca, the products
Solaveil CT-10 W and Solaveil CT 100 from Uniqema and the product Eusolex TAVO
from Merck,
- with silica, alumina and alginic acid, such as the product MT-100 AQ from
Tayca,
- with alumina and aluminium laurate, such as the product Microtitanium Dioxide
MT 100 S from Tayca,
- with iron oxide and iron stearate, such as the product Microtitanium Dioxide MT
00 F from the company Tayca,
- with zinc oxide and zinc stearate, such as the product BR 351 from Tayca,
- with silica and alumina and treated with a silicone, such as the products
Microtitanium Dioxide MT 600 SAS, Microtitanium Dioxide MT 500 SAS or
Microtitanium Dioxide MT 100 SAS from Tayca,
- with silica, alumina and aluminium stearate and treated with a silicone, such as
the product STT-30-DS from Titan Kogyo,
- with silica and treated with a silicone, such as the product UV-Titan X 195 from
Kemira,
- with alumina and treated with a silicone, such as the products Tipaque TTO-55
(S) from Ishihara or UV Titan M 262 from Kemira,
- with triethanolamine, such as the product STT-65-S from Titan Kogyo,
- with stearic acid, such as the product Tipaque TTO-55 (C) from Ishihara,
- with sodium hexametaphosphate, such as the product Microtitanium Dioxide MT
150 W from Tayca,
- with octyltrimethylsilane, sold under the trade name T 805 by Degussa Silices,
- with a polydimethylsiloxane, sold under the trade name 70250 Cardre UF
TiO2SI3 by Cardre,
- anatase/rutile T1O2 treated with a polydimethylhydrosiloxane, sold under the
trade name Microtitanium Dioxide USP Grade Hydrophobic by Color Techniques.
The non-coated titanium oxide pigments are sold, for example, by Tayca under
the trade names Microtitanium Dioxide MT 500 B and Microtitanium Dioxide MT
600 B, by Degussa under the name P 25, by Wackherr under the name
Transparent titanium oxide PW, by Miyoshi Kasei under the name UFTR, by
Tomen under the name ITS and by Tioxide under the name Tioveil AQ.
The non-coated zinc oxide pigments are, for example:
- those sold under the Z-Cote name by Sunsmart;
- those sold under the Nanox name by Elementis;
- those sold under the name Nanogard WCD 2025 by Nanophase Technologies.
The coated zinc oxide pigments are, for example:
- those sold under the name Zinc Oxide CS-5 by Toshibi (ZnO coated with
polymethylhydrosiloxane);
- those sold under the name Nanogard Zinc Oxide FN by Nanophase
Technologies (as a 40% dispersion in Finsolv TN, C12-C15 alkyl benzoate);
- those sold under the names Daitopersion Zn-30 and Daitopersion Zn-50 by
Daito (dispersions in oxyethylenated
polydimethylsiloxane/cyclopolymethylsiloxane comprising 30% or 50% of zinc
oxides coated with silica and polymethylhydrosiloxane);
- those sold under the name NFD Ultrafine ZnO by Daikin (ZnO coated with
perfluoroalkyl phosphate and copolymer based on perfluoroalkylethylacrylate as a
dispersion in cyclopentasiloxane);
- those sold under the name SPD-Z1 by Shin-Etsu (ZnO coated with siliconegrafted
acrylic polymer, dispersed in cyclodimethylsiloxane);
those sold under the name Escalol Z 100 by ISP (alumina-treated ZnO dispersed
in an ethylhexyl methoxycinnamate/PVP-hexadecene copolymer/methicone
mixture);
- those sold under the name Fuji ZnO-SMS-1 0 by Fuji Pigment (ZnO coated with
silica and polymethylsilsesquioxane);
- those sold under the name Nanox Gel TN by Elementis (ZnO dispersed at 55%
in C12-C15 alkyl benzoate with hydroxystearic acid polycondensate).
The non-coated cerium oxide pigments can, for example, be those sold under the
name Colloidal Cerium Oxide by Rhone-Poulenc.
The non-coated iron oxide pigments are sold, for example, by Arnaud under the
names Nanogard WCD 2002 (FE 45B), Nanogard Iron FE 45 BL AQ, Nanogard
FE 45R AQ and Nanogard WCD 2006 (FE 45R) or by Mitsubishi under the name
TY-220.
The coated iron oxide pigments are sold, for example, by Arnaud under the
names Nanogard WCD 2008 (FE 45B FN), Nanogard WCD 2009 (FE 45B 556),
Nanogard FE 45 BL 345 and Nanogard FE 45 BL or by BASF under the name
Transparent Iron Oxide.
Mention may also be made of mixtures of metal oxides, in particular of titanium
dioxide and cerium dioxide, including the mixture of equal weights of titanium
dioxide and cerium dioxide which are coated with silica, sold by Ikeda under the
name Sunveil A, and also the mixture of titanium dioxide and zinc dioxide coated
with alumina, silica and silicone, such as the product M 261 sold by Kemira, or
coated with alumina, silica and glycerol, such as the product M 2 11 sold by
Kemira.
According to the invention, coated or non-coated titanium oxide pigments are
particularly preferred.
According to a specific form of the invention, the insoluble screening agents can
be composed of composite particles with an average size of between 0.1 and 30
miti and comprising a matrix and an inorganic UV screening agent, the content of
inorganic screening agent in a particle ranging from 1% to 70% by weight.
These composite particles can be chosen from spherical composite particles,
lamellar composite particles or their mixtures.
The term "spherical" is understood to mean that the particle exhibits a sphericity
index, that is to say the ratio of its greatest diameter to its smallest diameter, of
less than 1.2.
The term "non-spherical" is understood to mean particles in three dimensions
(length, width, thickness or height) for which the ratio of the greatest dimension to
the smallest dimension is greater than 1.2. The dimensions of the particles of the
invention are evaluated by scanning electron microscopy and image analysis.
They comprise particles of parallelepipedal shape (rectangular or square surface),
discoid shape (circular surface) or ellipsoid shape (oval surface), characterized by
three dimensions: a length, a width and a height. When the shape is circular, the
length and the width are identical and correspond to the diameter of a disc,
whereas the height corresponds to the thickness of the disc. When the surface is
oval, the length and the width correspond respectively to the main axis and the
minor axis of an ellipse and the height corresponds to the thickness of the elliptic
disc formed by the platelet. When a parallelepiped is concerned, the length and
the width can be of identical or different dimensions: when they are of the same
dimension, the shape of the surface of the parallelepiped is square; in the contrary
case, the shape is rectangular. With regard to the height, it corresponds to the
thickness of the parallelepiped.
The spherical and non-spherical screening composite particles used according to
the present invention comprise a matrix and an inorganic UV screening agent.
The matrix comprises one or more organic and/or inorganic materials.
The inorganic UV screening agent is generally chosen from metal oxides,
preferably titanium, zinc or iron oxides or their mixtures and more particularly from
titanium dioxide T1O2.
These metal oxides can be provided in the form of particles with an average size
generally of less than 200 nm. Advantageously, the metal oxide particles used
exhibit an average size of less than or equal to 0.1 miti .
These metal oxides can also be provided in the form of layers, preferably
multilayers with an average thickness generally of less than 0.2 miti .
According to a first alternative form, the composite particles comprise a matrix
comprising an organic and/or inorganic material, in which matrix particles of
inorganic UV screening agent are included. According to this embodiment, the
matrix exhibits inclusions and particles of inorganic UV screening agent are
placed in the inclusions of the matrix.
According to a second alternative form, the composite particles comprise a matrix
made of an organic and/or inorganic material, which matrix is covered with at least
one layer of inorganic UV screening agent which can be connected to the matrix
using a binder.
According to a third alternative form, the composite particles comprise an
inorganic UV screening agent covered with at least one layer of an organic and/or
inorganic material.
The matrix can also be formed of one or more organic or inorganic materials.
There may then be a continuous phase of materials, such as an alloy, that is to
say, a continuous phase in which the materials can no longer be separated, or a
non-continuous phase of materials, for example composed of an organic or
inorganic material covered with a layer of another different organic or inorganic
material.
According to an alternative form, in particular when the spherical composite
particles comprise a matrix covered with a layer of UV screening agent, the
composite particles can furthermore be covered with an additional coating,
chosen in particular from biodegradable or biocompatible materials, lipid
materials, such as, for example, surfactants or emulsifiers, polymers and oxides.
Spherical composite particles
The inorganic materials which can be used in the matrix of the spherical
composite particles according to the present invention can be chosen from the
group formed by boron nitride, glass, calcium carbonate, barium sulfate,
hydroxyapatite, silica, silicate, magnesium sulfate, magnesium carbonate,
aluminium oxide, calcium silicate, calcium phosphate, magnesium oxide, bismuth
oxychloride and their mixtures.
The organic materials which can be used to form the matrix are chosen from the
group formed by poly(meth)acrylates, polyamides, silicones, polyurethanes,
polyethylenes, polypropylenes, polystyrenes, polyhydroxyalkanoates,
polycaprolactams, poly(butylene succinate^, polysaccharides, polypeptides,
polyvinyl alcohols, polyvinyl resins, fluoropolymers, waxes, polyesters, polyethers
and their mixtures.
Preferably, the matrix of the spherical composite particle comprises a material or
a mixture of materials chosen from:
- SiO2,
- polymethyl methacrylate,
- copolymers of styrene and of a C1/C5 alkyl (meth)acrylate derivative,
- polyamides, such as nylon.
The composite particles in spherical form are characterized by an average
diameter of between 100 nm and 30 miti , preferably between 300 nm and 20 miti
and more preferably between 500 nm and 10 miti .
According to a first alternative form, the spherical composite particles comprise a
matrix comprising an organic and/or inorganic material, in which matrix particles of
inorganic UV screening agent are included.
According to this first alternative form, the particles of inorganic UV screening
agent are characterized by an average elementary size generally of less than 0.2
miti . Advantageously, the metal oxide particles used exhibit an average
elementary size of less than or equal to 0.1 miti .
Mention may be made, as composite particles corresponding to this alternative
form, of the products Sunsil TIN 50 and Sunsil TIN 40 sold by Sunjin Chemical.
These spherical composite particles with an average size of between 2 and 7 miti
are formed of T1O2 encapsulated in a silica matrix.
Mention may also be made of the following particles:
- spherical composite particles with an average size of between 4 and 8 miti ,
comprising T1O2 and S1O2 and having the trade name Eospoly TR, sold by
Creations Couleurs,
- composite particles comprising T1O2 and a styrene/alkyl acrylate copolymer
matrix, sold under the name Eospoly UV TR22 HB 50 by Creations Couleurs,
- composite particles comprising T1O2 and ZnO and a PMMA matrix and having
the trade name Sun PMMA-T50, sold by Sunjin Chemical.
According to a second alternative form, the spherical composite particles
comprise a matrix made of an organic and/or inorganic material, which matrix is
covered with at least one layer of inorganic UV screening agent connected to the
matrix using a binder.
According to this second alternative form, the average thickness of the layer of
inorganic UV screening agent is generally approximately ten nanometres. The
average thickness of the layer of inorganic UV screening agent is advantageously
between 10 3 and 0.2 miti , preferably between 0.001 and 0.2 miti .
The spherical composite particles used according to the invention have a size of
between 0.1 and 30 miti , preferably between 0.3 and 20 miti and more
preferentially still between 0.5 and 10 miti .
Mention may be made, among the composite particles which can be used
according to the invention, of spherical composite particles comprising T1O2 and
SiO2 and having the trade name STM ACS-005051 0, supplied by JGC Catalysts
and Chemical.
According to a third alternative form, the spherical composite particles comprise
an inorganic UV screening agent covered with at least one layer of an organic
and/or inorganic material. According to this third alternative form, the particles of
inorganic UV screening agent are characterized by an average elementary size
generally of between 10 3 and 0.2 miti . Advantageously, the metal oxide particles
used exhibit an average elementary size of between 0.01 and 0.1 miti .
The spherical composite particles used according to the invention have a size of
between 0.1 and 30 miti , preferably between 0.3 and 20 miti and more
preferentially still between 0.5 and 10 miti .
Non-spherical composite particles
The organic materials which can be used to form the matrix of the non-spherical
screening particles are chosen from the group formed by poly(meth)acrylates,
polyamides, silicones, polyurethanes, polyethylenes, polypropylenes,
polystyrenes, polyhydroxyalkanoates, polycaprolactams, poly(butylene
succinate^, polysaccharides, polypeptides, polyvinyl alcohols, polyvinyl resins,
fluoropolymers, waxes, polyesters, polyethers and their mixtures.
Mention may preferably be made, among the organic materials which can be
used, of:
- triethoxycaprylylsilane,
- acrylic polymers, such as polymethyl methacrylate and acrylic copolymers
comprising other types of monomers, such as styrene,
- polyamides, such as nylon.
The inorganic materials which can be used in the matrix of the non-spherical
composite particles are chosen from the group formed by mica, synthetic mica,
talc, sericite, boron nitride, glass, calcium carbonate, barium sulfate,
hydroxyapatite, silica, silicate, magnesium sulfate, magnesium carbonate,
magnesium trisilicate, aluminium oxide, calcium silicate, calcium phosphate,
magnesium oxide, bismuth oxychloride and their mixtures. Preferably, these
inorganic materials are chosen from:
- silica,
- talc,
- mica,
- alumina.
The inorganic UV screening agent is generally chosen from metal oxides, in
particular from titanium, zinc or iron oxides and more particularly titanium dioxide
(Ti0 2) .
The non-spherical composite particles of the invention are characterized by three
dimensions, of which:
- the smallest is greater than 0.1 miti , preferably 0.3 miti and better still 0.5 miti ,
- the greatest is less than 30 miti , preferably 20 miti and better still 10 miti .
The ratio of the greatest dimension to the smallest dimension is greater than 1.2.
The dimensions of the particles of the invention are evaluated by scanning
electron microscopy and image analysis.
The non-spherical composite particles which can be used according to the
invention will preferably be platelet-shaped.
The term "platelet-shaped" is understood to mean a parallelepipedal shape.
They can be smooth, rough or porous.
The platelet-shaped composite particles preferably exhibit an average thickness
of between 0.01 and 10 miti , the average length is generally between 0.5 and 30
miti and the average width is between 0.5 and 30 miti .
The thickness is the smallest of the dimensions, the width is the medium
dimension and the length is the greatest of the dimensions.
According to a first alternative form, the composite particles comprise a matrix
comprising an organic and/or inorganic material, in which matrix particles of
inorganic UV screening agent are included.
According to this first alternative form, the particles of inorganic UV screening
agent are characterized by an average elementary size generally of less than 0.2
miti . Advantageously, the metal oxide particles used exhibit an average
elementary size of less than or equal to 0.1 miti .
According to a second alternative form, the composite particles comprise a matrix
made of an organic and/or inorganic material, which matrix is covered with at least
one layer of inorganic UV screening agent which can be connected to the matrix
using a binder.
According to this second alternative form, the average thickness of the layer of
inorganic UV screening agent is generally approximately ten nanometres. The
average thickness of the layer of inorganic UV screening agent is advantageously
between 10 3 and 0.2 miti , preferably between 0.01 and 0.2 miti .
The non-spherical composite particles used according to the invention have a size
of between 100 nm and 30 miti , preferably between 0.3 and 20 miti and more
preferentially still between 0.5 and 10 miti .
According to a third alternative form, the non-spherical composite particles
comprise an inorganic UV screening agent covered with at least one layer of an
organic and/or inorganic material. According to this third alternative form, the
particles of inorganic UV screening agent are characterized by an average
elementary size generally of between 10 and 0.2 miti . Advantageously, the metal
oxide particles used exhibit an average elementary size of between 0.01 and 0.1
miti .
Preferably, the inorganic UV screening agent used in the composite particle is
chosen from metal oxides, in particular from titanium, zinc or iron oxides and more
particularly titanium dioxide (T1O2).
Preferably, the matrix of the composite particle comprises a material or a mixture
of materials chosen from:
SiO2,
alumina,
mica,
an alumina/triethoxycaprylylsilane mixture,
talc,
PMMA (polymethyl methacrylate),
Nylon.
More preferably, the matrix of the composite particle is composed of a material or
a mixture of materials chosen from:
alumina,
an alumina/triethoxycaprylylsilane mixture,
talc,
silica,
mica.
Mention may also be made, among the composite particles which can be used
according to the invention, of the following particles:
- composite particles comprising Ί O 2 and an alumina matrix, with the trade
name Matlake OPA, sold by Sensient LCW,
- composite particles comprising Ί O 2 and an alumina/triethoxycaprylylsilane
matrix, with the trade name Matlake OPA AS, sold by Sensient LCW,
- composite particles comprising ultrafine Ί O2 particles deposited on the
surface of talc platelets, with the trade name TTC 30, sold by Miyoshi
Kasei,
- composite particles comprising ultrafine Ί O2 particles deposited on the
surface of talc platelets, with the trade name Silseem Mistypearl Yellow,
sold by Nihon Koken Kogyo (NKK).
The inorganic UV screening agent or agents are preferably present in the
compositions according to the invention at a content, as active material, ranging
from 0.1 % to 20% by weight and in particular from 0.5% to 15% by weight, with
respect to the total weight of the composition.
A person skilled in the art will choose the said active agent or agents according to
the effect desired on the skin, hair, eyelashes, eyebrows or nails.
The cosmetic compositions according to the invention have applications in a great
number of treatments, in particular cosmetic treatments, of the skin, lips and hair,
including the scalp.
Another subject-matter of the present invention consists of the use of the
compositions according to the invention as defined above in the manufacture of
products for the cosmetic treatment of the skin, lips, nails, hair, eyelashes,
eyebrows and/or scalp, in particular care products, anti-sun products and make
up products.
The cosmetic compositions according to the invention can be used, for example,
as make-up products.
ASSEMBLY
According to another aspect, the invention also relates to a cosmetic assembly
comprising:
i) a container delimiting one or more compartment(s), the said container being
closed by a closing member and optionally not being leaktight; and
ii) a make-up and/or care composition in accordance with the invention placed
inside the said compartment(s).
The container can, for example, be in the form of a pot or a case.
The closing member can be in the form of a lid comprising a cap mounted so as to
be able to move by translation or by pivoting relative to the container housing the
said make-up and/or care composition(s).
The examples which follow serve to illustrate the invention without, however,
exhibiting a limiting nature. In these examples, the amounts of the composition
ingredients are given as % by weight, with respect to the total weight of the
composition.
EXAMPLES
Evaluation protocols
in vivo SPF:
The Sun Protection Factor (SPF) of a product is evaluated according to the
International Method published by COLIPA /CTFA SA /JCIA (May 2006).
The Sun Protection Factor is the ratio of the Minimal Erythemal Dose obtained in
the presence of product (2 mg/cm2) (MEDp) to the Minimal Erythemal Dose
obtained without product (MEDnp).
SPF = MEDp/MEDnp
The Minimal Erythemal Dose is defined as being the amount of energy necessary
to produce the first unambiguously perceptible redness, in the clearly defined
outlines, evaluated from 16 to 24 hours after exposure to a solar simulator, at 6
increasing doses of UV radiation (progression of 12%).
The test has to be carried out on at least 10 and no more than 20 subjects, and it
has to satisfy the statistical criterion (95% confidence interval falls with the range
± 17% mean SPF).
Transparency
The compositions are applied in a proportion of 2 mg/cm2 to an area of 2 x 2 cm2
delimited on the inside of the forearm, the skin colour of which, characterized by
the ITA angle, is between 28 and -30.
The following series of colorimetric measurements were carried out using a
Minolta CM-508d spectrocolorimeter:
1°) before application of the composition,
2°) 2 minutes after application,
3°) after wiping with a paper handkerchief (standardized body movements).
The results are expressed in the (L*, a*, b*) system, in which L* represents the
luminance, a* represents the red-green axis (-a* = green, +a* = red) and b*
represents the yellow-blue axis (-b* = blue, +b* = yellow). Thus, a* and b* express
the hue of the skin.
For the evaluation of the intensity of the colouring, the factor of interest is the D I_*
relationship, which reflects the darkening/lightening of the colour: the greater the
value of A * , the greater the whitening effect:
D I_* = L* bare skin - L* skin with product
For the evaluation of the change in the colour of the skin, the factor of interest is
D E* , which reflects the variation in the colour: the greater the value of D E , the
greater the modification to the colour in comparison with the initial colour. The
colour difference is obtained using the Hunter colour difference formula in the L*,
a*, b* colorimetric space:
(D E*)2 = [(D I_*)2 + (Aa*) 2 + (Ab*)2]
where
Aa* = a* bare skin - a* skin with product
Ab* = b* bare skin - b* skin with product
Examples A, B and C
Ingredients A* B C
Talc
38.25 48.5 38.25
Luzenac OO from Luzenac
Mica (CI 7701 9)
25 25 25
Concord 1000 from Sciama
Polytetrafluoroethylene
Ceridust 9205 F from Clariant 4 4 4
Polymethyl methacrylate
Micropearl M 100 from
5 5 5
Matsumoto Yushi-Seiyaku
Butyl Methoxydibenzoyl
3 3
Hexylbenzoate
Octocrylene 7 7
Ethylhexyl Salicylate 5 5
Ci2 -Ci 5 Alkyl benzoate 5 5
* composition according to the invention
Manufacturing process
For the compositions A* and C:
The organic screening agents are heated to 75°C with magnetic stirring. The
aerogel particles of hydrophobic silica: Silica Silylate (composition A* ) or silica
(composition C), are added and homogenization is carried out with a spatula until
a powder is obtained. The fillers and the powder obtained above are introduced
into a Backer vessel. Stirring is begun (paddles: 500 rev/min; E-motors: 1000
rev/min) for 10 minutes. It is confirmed that the powder is homogeneous. The
glycerol is introduced into the Backer vessel. Stirring is begun (paddles: 500
rev/min; E-motors: 1000 rev/min) for 15 minutes. It is confirmed that the powder is
homogeneous. The pearlescent agent is introduced into the Backer vessel.
Stirring is begun (paddles: 500 rev/min; E-motors: 1000 rev/min) for 5 minutes. It
is confirmed that the powder is homogeneous. The powder is sieved.
For the formulation B:
The fillers and the Titanium Dioxide (and) Aluminium Hydroxide (and) Stearic Acid
are introduced into the Backer vessel. Stirring is begun (paddles: 500 rev/min; Emotors:
1000 rev/min) for 10 minutes. It is confirmed that the powder is
homogeneous. The glycerol is introduced into the Backer vessel. Stirring is begun
(paddles: 500 rev/min; E-motors: 1000 rev/min) for 15 minutes. It is confirmed that
the powder is homogeneous. The pearlescent agent is introduced into the Backer
vessel. Stirring is begun (paddles: 500 rev/min; E-motors: 1000 rev/min) for 5
minutes. It is confirmed that the powder is homogeneous. The powder is sieved.
Evaluation of the colour
Criteria evaluated A* B (with TiO2) C (with
conventional
silica)
Feasibility Yes Yes No
SPF Cannot be
30 30 carried out
AL* before wiping Cannot be
6.2 11.2 carried out
DE* before wiping Cannot be
8.9 17.4
carried out
AL* after wiping Cannot be
2.5 6.5
carried out
DE* after wiping Cannot be
3.2 10.8
carried out
* composition according to the invention
It is found that, for an equivalent screening system, the anti-sun powder can be
produced with a hydrophobic silica aerogel (composition A according to the
invention), whereas it cannot be produced with a silica of the state of the art
(composition C). It is found that the composition A (silica aerogel + lipophilic
organic UV screening agent) and the composition B (hydrophobic silica aerogel +
inorganic UV screening agent) can be produced and both exhibit an in vivo SPF of
30. Nevertheless, before wiping and after wiping, the composition A (according to
the invention) exhibits a DE and a AL which are lower than those given by the
composition C (state of the art). Thus, the composition according to the invention,
A, has a less significant colouring and whitening effect and is therefore more
transparent.
Example D according to the invention (SPF 50)
(and) Carmin (CI 77019 + 771 63
+ 75470)
Manufacturing process: identical to that for the preceding composition A.
Evaluation
It is found that the anti-sun powder D can be produced and that it exhibits an SPF
of 50. It is found that the composition D exhibits a low DE and a low AL, before
wiping and after wiping. Thus, the composition D according to the invention has a
very low colouring and whitening effect and is therefore not very covering.

CLAIMS
1. Solid connposition comprising, in a cosmetically acceptable medium:
a) at least one pulverulent phase
b) at least one lipophilic organic UV screening agent
characterized in that the pulverulent phase comprises at least aerogel particles of
hydrophobic silica exhibiting a specific surface per unit of weight (Sw) ranging
from 200 to 1500 m2/g, preferably from 600 to 1200 m2/g and better still from 600
to 800 m2/g, and a size, expressed as volume-average diameter (D[0.5]), of less
than 1500 miti and preferably ranging from 1 to 30 miti , more preferably from 5 to
25 miti , better still from 5 to 20 miti and even better still from 5 to 15 miti .
2. Composition according to Claim 1, in the form of a loose or compact powder.
3. Composition according to Claim 1 or 2, characterized in that the aerogel
particles of hydrophobic silica exhibit a size, expressed as volume-average
diameter, ranging from 5 to 25 miti , better still from 5 to 20 miti and even better still
from 5 to 15 miti .
4. Composition according to one of Claims 1 to 4, in which the aerogel particles of
hydrophobic silica are silica particles modified at the surface with trimethylsilyl
groups.
5. Composition according to any one of Claims 1 to 4, characterized in that the
aerogel particles of hydrophobic silica exhibit a packed density p ranging from
0.04 g/cm3 to 0.1 0 g/cm3 and preferably from 0.05 g/cm3 to 0.08 g/cm3.
6. Composition according to any one of Claims 1 to 5, characterized in that the
aerogel particles of hydrophobic silica exhibit a specific surface per unit of volume
Sv ranging from 5 to 60 m2/cm3, preferably from 10 to 50 m2/cm3 and better still
from 15 to 40 m2/cm3.
7. Composition according to any one of Claims 1 to 6, characterized in that the
aerogel particles of hydrophobic silica have an oil absorption capacity, measured
at the wet point, ranging from 5 to 18 ml/g, preferably from 6 to 15 ml/g and better
still from 8 to 12 ml/g of particles.
8. Composition according to any one of Claims 1 to 7, where the lipophilic organic
UV screening agent or agents are chosen from cinnamic derivatives;
anthranilates; salicylic derivatives; dibenzoylmethane derivatives; camphor
derivatives; benzophenone derivatives; b ,b -diphenylacrylate derivatives; triazine
derivatives; benzotriazole derivatives; benzalmalonate derivatives; imidazolines;
p-aminobenzoic acid (PABA) derivatives; benzoxazole derivatives; screening
polymers and screening silicones; dimers derived from cc-alkylstyrene; 4,4-
diarylbutadienes; merocyanine derivatives; and their mixtures.
9. Composition according to Claim 8, where the lipophilic organic UV screening
agent or agents are chosen from:
Butyl Methoxy Dibenzoylmethane,
Octocrylene,
Ethylhexyl Salicylate,
n-Hexyl 2-(4-diethylamino-2-hydroxybenzoyl)benzoate,
Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine,
Ethylhexyl Triazone,
Diethylhexyl Butamido Triazone,
Drometrizole Trisiloxane, and their mixtures.
10. Composition according to any one of Claims 1 to 9, additionally comprising at
least one insoluble UV screening agent chosen from insoluble organic UV
screening agents, inorganic UV screening agents and composite materials
comprising an organic or inorganic matrix and at least one inorganic UV screening
agent.
11. Composition according to any one of Claims 1 to 10, where the pulverulent
phase comprises at least one additional filler preferably composed of a mixture of
spherical particles and lamellar particles.
12. Composition according to Claim 11, where
- the spherical particles are chosen from polyamide powders, polymethyl
methacrylate microspheres, polytetrafluoroethylene powders and their mixtures,
and
- the lamellar particles are chosen from an expanded perlite, a talc, a mica and
their mixtures.
13. Composition according to any one of Claims 1 to 12, comprising at least one
liquid fatty phase preferably comprising at least one volatile or non-volatile
hydrocarbon oil and/or one volatile or non-volatile silicone oil.
14. Composition according to any one of Claims 1 to 13, comprising at least one
polyol.
15. Cosmetic method for caring for and/or making up human keratinous
substances, in particular the skin of the body or of the face or the hair, comprising
at least the application, to the surface of the keratinous substance, of at least one
composition as defined according to any one of Claims 1 to 14.