U.S. patent application number 10/876527 was filed with the patent office on 2005-02-10 for porous particles loaded with cosmetically or pharmaceutically active compounds.
This patent application is currently assigned to L'OREAL. Invention is credited to Biatry, Bruno, Saint-Leger, Didier, Simonnet, Jean-Thierry.
Application Number | 20050031699 10/876527 |
Document ID | / |
Family ID | 34119431 |
Filed Date | 2005-02-10 |
United States Patent
Application |
20050031699 |
Kind Code |
A1 |
Simonnet, Jean-Thierry ; et
al. |
February 10, 2005 |
Porous particles loaded with cosmetically or pharmaceutically
active compounds
Abstract
The present invention relates to individualized porous
particles, characterized in that they have a volume-average
diameter of less than or equal to 10 .mu.m and a specific surface
area of greater than or equal to 1 m.sup.2/g, and in that they
comprise at least one cosmetically or pharmaceutically active
compound at least present inside said particles.
Inventors: |
Simonnet, Jean-Thierry;
(Cachan, FR) ; Biatry, Bruno; (Vincennes, FR)
; Saint-Leger, Didier; (Courbevoie, FR) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
ALEXANDRIA
VA
22320
US
|
Assignee: |
L'OREAL
Paris
FR
75008
|
Family ID: |
34119431 |
Appl. No.: |
10/876527 |
Filed: |
June 28, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60487245 |
Jul 16, 2003 |
|
|
|
Current U.S.
Class: |
424/489 |
Current CPC
Class: |
A61K 2800/412 20130101;
A61P 29/00 20180101; A61P 31/04 20180101; A61Q 5/12 20130101; A61K
8/88 20130101; A61K 8/25 20130101; A61K 8/0279 20130101; A61P 17/08
20180101; A61Q 5/02 20130101; A61P 17/18 20180101; A61K 2800/56
20130101; A61Q 19/00 20130101; A61Q 5/00 20130101 |
Class at
Publication: |
424/489 |
International
Class: |
A61K 009/14 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 26, 2003 |
FR |
03 07747 |
Claims
1. Individualized porous particles, characterized in that they have
a volume-average diameter of less than or equal to 10 .mu.m and a
specific surface area of greater than or equal to 1 m.sup.2/g, and
in that they comprise at least one cosmetically or pharmaceutically
active compound at least present inside said particles.
2. Particles according to claim 1, characterized in that they have
a specific surface area ranging from 2.5 to 1000 m.sup.2/g, and in
particular from 3 to 750 m.sup.2/g.
3. Particles according to either one of the preceding claims,
characterized in that they have a mass by volume of greater than or
equal to 0.15 g/cm.sup.3, and in particular ranging from 0.2 to 5
g/cm.sup.3.
4. Particles according to any one of the preceding claims,
characterized in that they have a volume-average diameter of
greater than or equal to 0.1 .mu.m, and in particular ranging from
0.5 to 8 .mu.m.
5. Particles according to any one of the preceding claims,
characterized in that they have a polydispersity index ranging from
1 to 4, and in particular less than or equal to 3.
6. Particles according to any one of the preceding claims,
characterized in that they are provided in the form of a
powder.
7. Particles according to any one of the preceding claims,
characterized in that they derive from organic porous
particles.
8. Particles according to claim 7, characterized in that said
organic porous particles are chosen from particles of Nylon 6,
Nylon 6-6, Nylon 12 and Nylon 6-12 and particles of poly(methyl
methacrylate).
9. Particles according to any one of claims 1 to 6, characterized
in that they derive from inorganic porous particles.
10. Particles according to claim 9, characterized in that said
inorganic porous particles are chosen from particles of silica, of
alumina-silica, of hydroxyapatite, of titanium dioxide or of
mixtures thereof.
11. Particles according to any one of the preceding claims,
characterized in that they derive from porous particles made of an
organic and inorganic composite material.
12. Particles according to any one of the preceding claims,
characterized in that the ratio by weight of the active compound(s)
to the porous particles not loaded with active compound(s) is from
1/1000 to 10/1, and in particular from 1/100 to 1/1.
13. Particles according to any one of the preceding claims,
characterized in that they comprise at least one cosmetically or
pharmaceutically active compound chosen from antibacterial agents,
antifungal agents, sebum regulators, sebum stimulators, keratolytic
agents, agents for treating acne, antibiotics, hair loss
inhibitors/hair growth stimulators, agents which inhibit the growth
of head hair or of body hair, anti-dandruff agents, antioxidants,
astringents, pore-reducing agents, antiperspirant agents, vitamins,
anti-inflammatory agents, and mixtures thereof.
14. Cosmetic or pharmaceutical composition, characterized in that
it comprises particles as defined in any one of claims 1 to 13.
15. Cosmetic or pharmaceutical composition according to claim 14,
characterized in that the proportion by weight of said particles
relative to the total weight of said composition is from 0.1 to
50%, and in particular from 0.2 to 20%.
16. Cosmetic or pharmaceutical composition according to either one
of claims 14 and 15, characterized in that it is provided in the
form of a lotion, an O/W emulsion, a W/O emulsion, or an aqueous or
aqueous-alcoholic gel, or in anhydrous form, such as a stick, a
spray or a compact or free powder.
Description
[0001] The present invention relates to individualized porous
particles having a volume-average diameter of less than or equal to
10 .mu.m and containing at least one cosmetically or
pharmaceutically active compound, and to their use in particular
for transporting and releasing said active compound in the
pilosebaceous unit.
[0002] To increase the efficacy of formulations for topical
application, whether they are cosmetic or pharmaceutical in type, a
certain number of methods have already been proposed which aim to
improve the penetration of the active molecules into the stratum
comeum forming the superficial layer of the skin. By way of
examples of these methods, mention will be made of those using, as
vehicle for these active molecules, liposomes, nanocapsules, O/W
emulsions, short alcohols, glycols, etc.
[0003] The pilosebaceous unit forms, within the stratum corneum,
the epidermis and the dermis, an invagination comprising a hair
follicle and a sebaceous gland. It is the site of considerable
biological and enzymatic activity which has a major effect on the
appearance of the skin. Among these effects, mention may be made,
for example, of the influence of the production of the sebum on the
greasy or dry nature of the skin, and the influence on the growth
or on the loss of growth of the body hair or of the head hair on
the pilosity of the skin. The pilosebaceous unit can also be the
subject of an inflammatory process. Such a process can have various
causes and can in particular be related to the presence of
microorganisms. This process can result in or contribute to the
manifestation of a certain number of skin conditions such as acne.
In addition, the pilosebaceous unit constitutes a potential route
of passage for agents intended to act on deep skin tissues, for
example for agents of the deep antiwrinkle type, of the slimming
type, etc.
[0004] The structure of this pilosebaceous unit, both by virtue of
its morphology with the presence of a hair, and by virtue of its
physiology with a continuous flow of sebum, naturally opposes the
penetration and/or the diffusion of active compounds within and
into the depths of this structure.
[0005] However, methods for targeting active compounds into the
pilosebaceous unit have already been proposed.
[0006] Thus, Application EP 0 375 520 describes the use of
microspheres of natural or synthetic polymers or of fatty
substances with a melting point above 50.degree. C., loaded at
least with an active product, and in which at least 80% by weight
of these microspheres are between 3 .mu.m and 10 .mu.m in diameter,
for preferentially transporting the active product into the
pilosebaceous unit. The microspheres described in that application
are either microspheres consisting of crosslinked materials, or
solid microspheres loaded by partial solubilization of their
constitutive materials, and which have a specific surface area of
less than 1 m.sup.2/g. In addition, the processes for preparing
microspheres described in that document, which comprise the
encapsulation of the active compound either by means of solvents
having sufficient affinity with respect to the material making up
the microsphere, or by the "emulsification-evaporation" method,
only allow an approximate control of the homogeneity of the
microspheres obtained and therefore result, besides their low
capacity to load the active compound(s), in a variation of this
capacity and also in a variation of their capacity to release the
active compound(s) in the pilosebaceous unit.
[0007] Application WO 02/07674 proposes a method for increasing the
penetration of an active compound into the pilosebaceous unit using
a composition in the form of microspheres or of liposomes having
the property of being introduced into the follicle and of swelling
therein by virtue of subsequently being in contact with a swelling
agent, so as to generate therein a passage into the follicle.
However, WO 02/07674 does not provide any concrete example
illustrating the method proposed and does not therefore make it
possible to verify the effectiveness thereof.
[0008] U.S. Pat. No. 6,287,549 describes a method of hair removal
using a composition comprising organic microparticles loaded with
chromophore agents, in which at least 80% by weight of the
microparticles used are between 3 and 10 .mu.m in size, in order to
transport the chromophore agent into the pilosebaceous unit. These
microparticles may be of various types and may be loaded with
chromophores either as they are formed, or by impregnation of
already formed microcapsules. In these microparticles, the
compounds transported are not active compounds as such, since they
require the intervention of an outside factor in order to be able
to exercise an effect. In addition, the exercising of this effect
does not require their release from the microparticles. Moreover,
that document, which explicitly provides for an optional step of
application of a composition for solubilizing the chromophores so
as to allow their release from the microparticles, does not suggest
the possibility of a passive release and even illustrates the
existence of a preconceived idea against this.
[0009] U.S. Pat. No. 4,690,825 describes vehicles consisting of
porous particles which are between 10 .mu.m and 100 .mu.m in size,
for the controlled release of active ingredients. These particles
are prepared by copolymerization of monomers based on styrene or on
vinyl stearate and on divinylbenzene, or on methyl methacrylate and
on ethylene glycol dimethyl methacrylate, in the presence of a
porogen which is also the active ingredient. There is therefore a
risk that the product obtained will contain residues from the
process for preparing it, which is likely to affect its
innocuity.
[0010] Application WO 99/53904 describes soft capsules containing
an oily suspension or a silicone/polyethylene glycol emulsion and
spherical porous microparticles prepared in particular according to
U.S. Pat. No. 4,690,825 mentioned above. More precisely, this
application describes porous microparticles having a mean particle
diameter by weight of 20 .mu.m, loaded either with retinol or with
ascorbic acid.
[0011] Finally, U.S. Pat. No. 6,387,995 describes a process for
producing an adsorbent polymer in the form of agglomerated, i.e.
non-individualized, microparticles with a very low mass by volume
ranging from 0.02 g/cm.sup.3 to 0.1 g/cm.sup.3, capable of trapping
lipophilic compounds. The amount of compound trapped in the
particles is negligeable compared with that of the compound trapped
in the space formed by the agglomerated particles.
[0012] It has now been discovered that it is possible to transport
at least one active compound and to release it in the pilosebaceous
unit with increased effectiveness compared to the embodiments
discussed above. The means found also makes it possible to improve
the encapsulation of the active compound, compared to the solutions
proposed to date, while at the same time exhibiting a particularly
satisfactory innocuity.
[0013] According to a first aspect, the present invention relates
to individualized porous particles having a volume-average diameter
of less than or equal to 10 .mu.m and a specific surface area of
greater than or equal to 1 m.sup.2/g, comprising at least one
cosmetically or pharmaceutically active compound at least present
inside said particles.
[0014] According to a second aspect, the present invention relates
to a cosmetic or pharmaceutical composition comprising particles as
defined above.
[0015] The expression "porous particles" denotes particles having a
structure containing pores.
[0016] This structure may be of matricial type, like a sponge. It
may also be of vesicular type, i.e. the particle has an internal
cavity delimited by a porous wall.
[0017] The porosity associated with the size of the particles is
characterized quantitatively by their specific surface area. The
porous particles of the invention have a specific surface area,
measured according to the BET method, of greater than or equal to 1
m.sup.2/g.
[0018] The expression "individualized particles" denotes particles
which are not grouped together in the form of an aggregate or of an
agglomerate. These particles have in particular a mass by volume of
greater than or equal to 0.15 g/cm.sup.3, and in particular ranging
from 0.2 to 5 g/cm.sup.3.
[0019] The expression "cosmetically or pharmaceutically active
compound" is intended to mean, in the context of the present
invention, a compound which, by itself, i.e. not requiring the
involvement of an outside agent to activate it, has biological
activity. In addition, this activity needs the compound to be in
direct contact with its target.
[0020] The particles used according to the present invention derive
from preformed porous particles, i.e. particles formed in the
absence of the compound(s) to be encapsulated.
[0021] For the purpose of the present invention, the expression
"loaded particles" will be used hereinafter to denote the particles
according to the invention in such a way as to distinguish them
from the particulate material from which they derive and which does
not contain active compound.
[0022] The loaded particles according to the invention do not
therefore substantially contain residues related to the process for
producing the particles from which they derive, which of course
constitutes an improvement in terms of innocuity compared to
particles which, in order to load the active compound, must be
formed in its presence. Moreover, they are not solid.
[0023] The particles of the invention are in particular
characterized by a high specific surface area, measured by BET.
[0024] The BET (BRUNAUER-EMMET-TELLER) method is a method well
known to those skilled in the art. It is in particular described in
"The journal of the American Chemical Society", vol. 60, page 309,
February 1938, and corresponds to the international standard ISO
5794/1 (annexe D). The specific surface area measured according to
the BET method corresponds to the total specific surface area, i.e.
it includes the surface area formed by the pores.
[0025] According to a particular embodiment, the particles of the
invention have a specific surface area, measured by BET, ranging
especially from 2.5 to 1000 m.sup.2/g, in particular from 3 to 750
m.sup.2/g.
[0026] As mentioned above, the particles according to the present
invention have a volume-average diameter of greater than or equal
to 10 .mu.m.
[0027] In fact, such particles can penetrate into the sebaceous
follicle by application of a mechanical force. This mechanical
force generally comes from a massage which, besides the pushing
that it exerts, generates a pump effect in the follicle.
[0028] The particles thus gradually reach the follicle canal in
which the active compound that they are carrying can then diffuse
and, possibly, reach the tissues surrounding the follicle canal. On
the other hand, the carrier, which constitutes the particle, is
then discarded by virtue of the flow of sebum and/or the growth of
the body hair, thus making it possible to avoid any adverse
reaction by the organism with respect to the solid compound
constituting the particles.
[0029] It should be noted that particles having a diameter of
greater than 10 .mu.m, even with application of a similar
mechanical force, mostly remain located on the surface of the skin
without penetrating therein, and can therefore release the active
compound only on the cornified layer.
[0030] According to a particular embodiment of the invention, the
particles have a volume-average diameter of greater than or equal
to 0.1 .mu.m, and in particular ranging from 0.5 to 8 .mu.m.
[0031] According to a variant of the invention, the particles are
characterized by virtue of their particle size homogeneity. In
particular, they have a polydispersity index, PI, ranging from 1 to
4, and in particular less than or equal to 3. This polydispersity
index is defined as the ratio D(4.3)/D(3.2), in which D(4.3)
denotes the volume-average diameter and D(3.2) denotes the
surface-average diameter. These two values are commonly measured
using laser diffraction particle size measuring devices such as
that sold under the name "Mastersizer 2000" by the company
MALVERN.
[0032] The porous particles of the invention may have varied
shapes, especially globular, and in particular substantially
spherical.
[0033] The porous particles from which the loaded particles
according to the invention derive generally consist of materials
which are completely insensitive, especially in terms of
solubilization and plasticization, to the process for encapsulating
the active compounds, in particular when this involves an organic
solvent for the impregnation.
[0034] These particles may be of organic, inorganic or mixed type
and are most commonly provided in the form of a powder with, in
particular, a low volatility.
[0035] As porous particles of organic type, mention will be made,
by way of example, of particles of Nylon 6, Nylon 6-6, Nylon 12 or
Nylon 6-12, such as those sold by the company ATOFINA under the
generic name "Orgasol", and particles of poly(methyl methacrylate)
(PMMA) such as those sold under the name "Covabead.RTM." by the
company WAKER.
[0036] In a particular embodiment of the invention, the particles
used are chosen from the nylon particles mentioned above.
[0037] As porous particles of inorganic type, mention will be made,
by way of example, of particles consisting of silica such as those
sold under the name "God Balls" by the company SUZUKI OIL AND FAT
or those sold under the name "Sunsphere H series" by the company
ASAHI GLASS, alumina-silica particles such as those sold under the
name "Zeeosphere.RTM." by the company 3M, hydroxyapatite particles
such as those sold under the name "ASP.RTM." by the company SEKISUI
PLASTICS, or under the name "Hydroxyzomes" by the company ASAHI
GLASS, titanium dioxide particles such as those sold by the company
ISHIHARA, and particles made up of a mixture of these minerals.
[0038] In one embodiment of the invention, the particles used are
in particular chosen from silica particles and hydroxyapatite
particles.
[0039] The porous particles used in the present invention may also
consist of organic and inorganic composite materials.
[0040] The loaded particles according to the present invention
comprise at least one cosmetically or pharmaceutically active
compound, said compound being at least present inside the said
porous particles. The active compound can also be present at the
surface of the loaded particles, but in such a case, it is
generally present mostly inside said particles.
[0041] The ratio by weight of the active compound(s) to the porous
particles not loaded with active compound(s) is generally from
1/1000 to 10/1, in particular from 1/100 to 1/1.
[0042] The active compounds may be hydrophilic or lipophilic.
According to a particular variant of the invention, the loaded
particles comprise at least one lipophilic active compound. They
can also comprise at least one hydrophilic active compound, it
being possible for the latter to be sufficiently solubilized by
amphiphilic compounds present in the sebum to allow its
release.
[0043] The active compounds considered hereinafter are, without
distinction, hydrophilic or lipophilic.
[0044] Among the active compounds, mention may in particular be
made of:
[0045] antibacterial agents such as triclosan, IPBC
(iodo-3-propynyl-2-butyl carbamate), benzalkonium chloride,
chlorhexidine, etc.,
[0046] antifungal agents such as piroctone olamine, zinc
pyrithione, climbazole, rilopirox, ketoconazole, itraconazole,
etc.,
[0047] sebum regulators such as the iminodibenzyl or fluorene
derivatives as described in U.S. Pat. No. 6,355,687, the
substituted secondary amine derivatives as described in U.S. Pat.
No. 6,355,686, the glucuronic acid and glucosamine derivatives, and
their salts, as described in Patent Application EP 1 219 296, or
the combinations of niacinamides with a C.sub.11-C.sub.30 alkyl or
alkenyl ester of salicylic acid as described in Patent Application
WO 02/067889,
[0048] sebum stimulators such as DHEA and its synthetic or natural
derivatives, .alpha.-hydroxylated derivatives of vitamin D1 such as
those described in U.S. Pat. No. 6,369,099,
[0049] keratolytic agents such as salicylic acid and its
derivatives, for instance more particularly 5-n-octanoylsalicylic
acid, alpha-hydroxy acids such as those, for example, of glycolic
acid, lactic acid or malic acid, and resorcinol,
[0050] agents for treating acne, such as retinol and its
derivatives, retinoic acid and its all-trans or 13-cis isomers,
benzoyl peroxide, the cytochrome P450 inhibitors as described in
U.S. Pat. No. 6,399,774 and their derivatives, and azelaic
acid,
[0051] antibiotics which may or may not have a macrolide structure,
the avermectin compounds as described in U.S. Pat. No. 6,399,652,
[(2,4,6-triisopropylphenyl)-acetyl]sulphamic acid
2,6-diisopropylphenyl ester or a salt thereof, as inhibitor of
cholesteryl and wax ester synthesis, as described in Patent
Application WO 01/56556,
[0052] hair loss inhibitors and also hair growth stimulators such
as minoxidil, biotin, finasteride, 2,4 dipyrimidine N-oxide,
panthenol and their derivatives, flavanone T, or more generally any
plant extract, having anti-5-alpha-reductase type I or II
activity,
[0053] agents which inhibit the growth of head hair or of body
hair, such as the serine proteases described in U.S. Pat. No.
6,407,056, cafeic acid, quercetin, propyl gallate,
nordihydroguaiaretic acid or NDGA, indomethacin, eflornithine
hydrochloride, the plant extracts as described in U.S. Pat. No.
6,171,595, such as the extracts of clove, of rosehip, of burnet, of
gambir, etc., the compounds described in U.S. Pat. No. 6,075,052,
tetramisole, sodium orthovanadate, levamisole, disodium
chromoglycate, vanadium nitrate and gallium nitrate as described in
U.S. Pat. No. 6,020,006, and also the compounds described in
Patents U.S. Pat. Nos. 4,885,289, 4,720,489, 5,132,293, 5,096,911,
5,095,007, 5,143,925, 5,328,686, 5,440,090, 5,364,885, 5,411,991,
5,648,394, 5,468,476, 5,475,763, 5,455,608, 5,674,477, 5,728,736
and 5,652,273 and in Patent Applications WO 94/27586, WO 94/27563
and WO 98/03149. Use may also be made of the extracts of juniper as
described in U.S. Pat. No. 6,375,948,
[0054] anti-dandruff agents such as zinc pyrithione,
[0055] antioxidants such as butylhydroxytoluene (BHT), carotenoids
such as .beta.-carotene, lycopene, canthaxanthine, ubiquinone,
dibutylpentaerythrityl tetrahydroxycinnamate, vitamin E, trolox,
vitamin C and its derivatives,
[0056] astringents and pore-reducing agents, such as those
described in Patent Application WO 02/32392,
[0057] antiperspirant agents such as aluminium salts and zirconium
salts,
[0058] vitamins, other than those mentioned above, and such as
vitamin B3, vitamin K, vitamin H, vitamin PP, vitamin D, vitamin B6
and their derivatives, and
[0059] anti-inflammatory agents such as .alpha.-bisabolol,
dipotassium glycyrrhizinate, glycyrrhetinic acid and its
derivatives, ellagic acid, ursolic acid, ibuprofen, naproxen,
fenoprofen, carprofen, ketoprofen, steroidal anti-inflammatory
agents such as cortisone, pregnenolone, desonide, and mixtures of
alkolamines and of tyrosine, such as those described in Patent
Application EP 1 192 939.
[0060] The loaded particles of the present invention are prepared
according to conventional methods, in particular by
impregnation.
[0061] In particular, the loaded particles according to the
invention are obtained by impregnation of preformed porous
particles with at least one active compound. Advantageously, this
protocol does not require the presence of a porogen.
[0062] By way of example, the impregnation process consists in
presolubilizing the compound(s) to be encapsulated in a solvent
which is suitable and in an amount necessary and sufficient to
impregnate the particles, and then in bringing this mixture into
contact with porous particles in accordance with the invention. The
solvent is then evaporated off until a dry powder is obtained. The
powder thus obtained generally contains only a very small
proportion of residual solvent, of the order of 1/10 ppm.
[0063] As solvents which may be used in such an impregnation
process, mention may in particular be made of acetone, ethanol,
isopropanol, dichloromethane, ethyl acetate, etc. Of course, the
choice of solvent is made taking into account the nature of the
components of the porous particles and of the compounds to be
encapsulated.
[0064] When the compound to be encapsulated is in the form of a
liquid, it may be brought directly into contact with the porous
particles without the addition of a secondary solvent.
[0065] Those skilled in the art will take care to choose the
impregnation conditions so as to obtain a dry powder.
[0066] The loaded particles of the invention allow specific
administration of said cosmetically or pharmaceutically active
compound(s) into the pilosebaceous unit.
[0067] These particles can be introduced in various cosmetic or
pharmaceutical formulations intended for topical application.
[0068] The present invention therefore also relates to a cosmetic
or pharmaceutical composition comprising loaded particles as
defined above.
[0069] Of course, said composition may comprise only one type of
particles as defined above, or else a mixture of such
particles.
[0070] Generally, the composition contains from 0.1 to 50% by
weight, and in particular from 0.2 to 20% by weight, of particles
as defined above relative to the total weight of the
composition.
[0071] The composition according to the invention may also
comprise:
[0072] at least one cosmetically or pharmaceutically active
compound intended to act essentially outside the pilosebaceous
unit, and/or
[0073] at least one cosmetically or pharmaceutically acceptable
additive, and/or
[0074] a galenic carrier, which may be of any suitable type.
[0075] The term "carrier" is intended to denote any mode of vehicle
compatible with cosmetic or pharmaceutical use, namely of liquid
type such as water, an aqueous-alcoholic solvent, oil, or a mixture
thereof, or of solid type such as wax for example.
[0076] Care will, however, be taken to ensure that the optional
additional cosmetically or pharmaceutically active compound, the
optional additive and the optional carrier do not cause the release
of the active compound in the composition.
[0077] According to a particular embodiment, the compositions of
the invention are substantially free of surfactants.
[0078] The cosmetic or pharmaceutical composition may be provided
in the form of lotions, O/W or W/O emulsions, or aqueous or
aqueous-alcoholic gels, or alternatively in anhydrous form, such as
sticks, sprays or compact or free powders.
[0079] The compositions of the invention may be care compositions,
hygiene compositions or makeup compositions.
[0080] They may also be intended, for example, for use on the hair
and may in particular be shampoos, conditioners, hair lotions, in
particular for hair care.
[0081] They may also be makeup sticks such as lipsticks, or
personal hygiene sticks such as deodorants.
[0082] Examples presented hereinafter are given by way of
illustration and are not limiting in nature.
FIGURE
[0083] FIG. 1: Electron micrograph consisting of silica particles
containing triclosan in accordance with the invention.
EXAMPLE 1
[0084] Two compositions containing a lipophilic active compound,
5-n-octanoylsalicylic acid, namely respectively a gel containing 4
.mu.m porous particles of nylon ("Orgasol.RTM."), which is the
subject of the invention, and an O/W emulsion with the same mean
particle size are compared in terms of pilosebaceous unit-targeting
effectiveness. The amount of active principle,
5-n-octanoylsalicylic acid, is identical in the two types of
composition, and is set at 0.3% by weight.
The Compounds Tested
[0085]
1 Composition 1 (according to the invention) Poly(ammonium
acryloyldimethyltaurate) 0.50 g Porous particles of Nylon-12* 4.70
g 5-n-octanoylsalicylic acid 0.30 g Poloxamer 338 0.25 g
Demineralized water 94.25 g *The porous particles of Nylon-12 are
sold under the name "Orgasol 2002 UD Nat cos" by the company
ATOFINA.
[0086]
2 Composition 2 (comparative O/W emulsion) Xanthan gum 0.10 g
Glyceryl stearate 1.00 g Sodium hydroxide 0.10 g Cetyl alcohol 2.00
g Octyldodecanol 9.00 g Glycerol 3.00 g Hydrogenated polyisobutene
2.00 g Water 71.95 g 5-n-Octanoylsalicylic acid 0.30 g Paraffin oil
5.00 g Carbomer 0.30 g PEG-100 stearate 1.00 g Polysorbate 60 4.00
g Methylparaben 0.25 g
[0087] The study was carried out on eight volunteer individuals who
have oily skin exhibiting dilated pores on the forehead.
[0088] For each individual, after having carefully cleaned the face
with soap, 4 mg/cm.sup.2 of the composition to be tested are
applied to the left or right side half of the forehead, and the
area treated is then massaged for 1 minute and left to dry for 15
minutes. This application is repeated for 4 days under the same
conditions (i.e. a total treatment period of 5 days with a single
daily application).
[0089] On day 6, an epidermal sample is taken from each individual
by cyanoacrylate strip, applying onto the forehead of each
individual a glass slide onto which a drop of cyanoacrylate has
been deposited, and then, after drying, removing said slide, which
thus entrains an epidermal sample.
[0090] The follicles and the comedones are then removed from said
samples and their content is extracted in methanol. The amount of
active compound is quantified by HPLC.
[0091] The results are presented in Table 1 below.
3 TABLE 1 5-n-Octanoylsalicylic acid Number of comedones in pg per
comedone Area Area Area Area Testers composition 2 composition 1
composition 2 composition 1 Enrichment 1 29 34 439 656 50% 2 20 16
282 566 101% 3 25 27 121 200 66% 4 30 33 709 1288 82% 5 24 13 571
986 73% 6 29 19 468 836 79% 7 11 13 57 259 353% 8 28 25 144 433
201%
[0092] It is noted, according to the results set out above, that
composition 1 according to the invention, which contains the porous
particles loaded with 5-n-octanoylsalicylic acid, makes it possible
to significantly increase the amount of 5-n-octanoylsalicylic acid
in the follicle by a rate of at least 50%, compared with a
composition in the form of an emulsion containing the same amount
of 5-n-octanoylsalicylic acid.
[0093] This trial shows the effectiveness of the porous particles
of the invention for transporting active molecules into the
pilosebaceous unit.
EXAMPLE 2
Preparation of the Organic Particles Containing an Active
Compound
[0094]
4 Particle composition Porous particles of Nylon-12, sold under the
name "Orgasol 2002 7.5 g UD Nat Cos" .RTM. by the company ATOFINA
Triclosan 2.5 g
[0095] 2.5 g of triclosan are solubilized in 50 ml of acetone. 7.5
g of "Orgasol.RTM." are introduced into this mixture. The
dispersion is then introduced into a rotary evaporator in order to
eliminate the acetone. A powder loaded with triclosan is then
obtained.
[0096] The powder thus obtained can then be redispersed in water,
in a gel or in an emulsion. Care will be taken to ensure that the
composition into which the particles containing the triclosan are
introduced does not promote leaking of said triclosan into the
galenic carrier.
EXAMPLE 3
Preparation of Organic Particles Containing an Active Compound
[0097]
5 Particle composition Porous particles of silica sold under the
name "God Balls2 7.5 g EC .RTM." by the company SUZUKI OILS &
FATS Vitamin E 1.5 g 5-n-Octanoylsalicylic acid 1.0 g
[0098] 1.5 g of vitamin E and 1 g of 5-n-octanoylsalicylic acid are
solubilized in 50 ml of acetone. 7.5 g of "God Balls 2 EC.RTM."
porous particles are introduced into this mixture. The dispersion
is then introduced into a rotary evaporator in order to eliminate
the acetone. A powder loaded with vitamin E and with
5-n-octanoylsalicylic acid is then obtained.
[0099] The powder thus obtained can then be redispersed in water,
in a gel or in an emulsion. Care will, however, be taken to ensure
that the composition into which the particles containing the
vitamin E and the 5-n-octanoylsalicylic acid are introduced does
not promote leaking of these active agents into the galenic
carrier.
[0100] Similarly, a powder of particles was prepared with 7.5 g of
"God Balls 2 EC.RTM." porous particles and 2.5 g of triclosan. The
powder is observed under an electron microscope. A micrograph
thereof is shown in FIG. 1.
[0101] It is noted that the powder thus obtained consists of
individualized particles.
EXAMPLE 4
Anti-Acne Cream (Oil/Water Emulsion)
[0102]
6 Poly(ammonium acryloyldimethyltaurate) 0.40 g Xanthan gum 0.20 g
Preserving agents 0.80 g Disodium EDTA 0.05 g Glycerol 5.00 g
Demineralized water 75.04 g Porous particles according to Example 2
3.00 g Mixture of cetearyl alcohol/dimyristyl tartrate/C12-15
Pareth- 1.50 g 7/PPG-25-Laureth-25 Stearyl alcohol 1.00 g Mixture
of glyceryl stearate/PEG-100 stearate 2.00 g Cyclohexasiloxane
10.00 g Ethylhexyl methoxycinnamate 1.00 g Fragrance 0.01 g
[0103] This smooth and fresh cream makes it possible to combat
problems of acne with good effectiveness.
EXAMPLE 5
Tonic Lotion
[0104]
7 Butylene glycol 1.00 g Zinc oxide 0.50 g Lactic acid 0.10 g
Glycerol 1.00 g Propylene glycol 0.20 g PEG-60 hydrogenated castor
oil 0.15 g Ethanol 5.00 g 30 nm colloidal silica 0.50 g Porous
particles according to Example 2 1.00 g Demineralized water 90.33 g
Extract of Hamamelis virginiana 0.0002 g Menthoxypropanediol 0.01 g
Methylparaben 0.20 g Fragrance 0.01 g
EXAMPLE 6
W/O Emulsion
[0105]
8 Phase A: Isohexadecane 8.00 g Squalane 3.70 g
Polydimethylsiloxane (viscosity: 10 cst) 4.10 g Apricot kernel oils
2.30 g Lubrizol 5603 1.90 g Phase B: Ascorbic acid 2.00 g 50%
potassium hydroxide 1.20 g Demineralized water 67.80 g Glycerol
5.00 g Preserving agents 1.00 g Phase C: Particles according to
Example 2 3.00 g
[0106] Phase B is emulsified slowly, at ambient temperature, in
phase A, and then phase C is added.
* * * * *