Patent Application
20160008241
The present invention relates to a powdered composition for use in the preparation of cosmetic compositions having a whitening effect.
Many persons wish to have a paler, more radiant and/or more uniform complexion, and use cosmetic compositions for this purpose. Preferably, a whitening effect is then sought not only upon applying the cosmetic composition, but also during the time for which the whitening effect is produced in a longer term.
For this purpose, whitening and/or lightening agents have been developed and introduced into cosmetic compositions. Cosmetic compositions having a whitening or lightening effect are for example described in applications EP 1 859 835 (cosmetic composition for which the whitening agent is α-arbutin), CA 2,351,077 (cosmetic composition for which the whitening agent is ascorbic acid), FR 2 735 688 077 (cosmetic composition for which the whitening agent is an α-hydroxyacid in association with a titanium dioxide pigment) and FR 2 863 889 (cosmetic composition for which the whitening agent is an optical brightener).
Whitening agents are often not very stable since they degrade upon heat and/or by oxidation, notably in an aqueous medium. It is therefore necessary to develop cosmetic compositions or compositions for use in the preparation of cosmetic compositions, and for which the whitening agent is stabilized.
Moreover, the method for preparing a cosmetic composition typically comprises the mixing of different constituents of the cosmetic composition. This method is facilitated when <<all-in-one>> products comprising several of the constituents of the cosmetic composition may be used instead of the constituents taken individually. Thus, the method comprises less steps, involves less initial products and the sometimes expensive losses of constituents which may occur during the separate introduction of each constituent may be minimized.
Therefore there exists a need for providing <<all-in-one>>, products comprising a whitening agent for use in the preparation of cosmetic compositions having a whitening effect and:
For this purpose, according to a first object, the invention relates to a powdered composition consisting in:
This powdered composition is adapted so as to be introduced into a cosmetic composition. The inventors discovered that a cosmetic composition comprising this powdered composition has a whitening effect not only upon applying the cosmetic composition on the skin, but also an extended whitening effect over time when the cosmetic composition is applied daily, notably over a period of at least 9 days.
Without intending to be bound to particular theories, this extended effect over time would be due to the release of the whitening agent and/or of the lightening agent of the powdered composition, this release may notably occur during the preparation of the cosmetic composition, or upon application of the cosmetic composition.
Moreover, as explained above, the use of whitening agents is limited by the fact that these agents are often not very stable. Advantageously, the whitening agent and/or the lightening agent of the powdered composition degrade less than the same free whitening agents and/or lightening agents, because they are encapsulated in the encapsulant of the powdered composition. It is notably possible to store the powdered composition before it is introduced into a cosmetic composition without degradation of these agents.
The Pigment
The powdered composition comprises one or several pigments.
The pigment(s) present in the powdered composition according to the invention may independently be an organic, inorganic pigment or of a hybrid organic-inorganic nature or a mineral filler. These are typically inorganic pigments.
The inorganic pigment may for example be selected from titanium dioxide, zinc oxide, zirconium or cerium oxides, aluminium oxide, as well as iron or chromium oxides, manganese violet, ultramarine blue, chromium hydrate, ferric blue and mixtures thereof. The pigments may be used as such or optionally surface-treated, in the form of surface-treated pigments or of surface-treated nanopigments.
The preferred inorganic pigments are titanium dioxide, zinc oxide, zirconium dioxide, aluminium oxide and mixtures thereof, and preferably titanium dioxide or zinc oxide and mixtures thereof.
The organic pigment may for example be selected from carbon black, such as D&C black no. 2, red organic pigments, such as D&C Red no. 6, no. 7, no. 21, no. 27, no. 28, no. 30, no. 33, no. 36, no. 40, and cochineal carmine, blue organic pigments, such as copper phthalocyanine and FD&C Blue no. 1 lacquer, and yellow organic pigments such as D&C yellow no. 10 lacquer, FD&C yellow no. 5 and no. 6 lacquers.
As mineral fillers adapted to the application of the invention, mention may notably be made of talcum, kaolin, alumina or silica.
Generally, the composition comprises from 80% to 97% by weight of pigment(s) based on the total weight of the powdered composition.
Whitening Agent
The powdered composition according to the invention comprises one or several whitening agents.
A whitening agent is a synthetic or natural chemical compound which gives the possibility of having a depigmenting effect on skin. Two methods are customarily used for demonstrating this depigmenting effect:
either by quantifying the melanin level in epidermises, or by using the CIE Lab L*a*b* method for evaluating the color of the epidermises (the parameter L* indicating brightness and the parameters a* and b* indicating the sense of colors), for example by applying the whitening agents on pigmented human epidermises restored in vitro of the MelanoDerm® (MatTek) type. From these values, it is possible to calculate the color deviation (ΔE*) which characterizes the color difference between two points (ΔE* being all the higher than the skin is darker), calculated according to the formula:
ΔE*=√{square root over ((ΔL*)2+(Δa*)2+(Δb*)2)}{square root over ((ΔL*)2+(Δa*)2+(Δb*)2)}{square root over ((ΔL*)2+(Δa*)2+(Δb*)2)}
These whitening agents may act according to several types of mechanisms:
The whitening agent(s) may independently be selected from kojic acid, α-arbutin, hydroquinone, vitamin C or one of its salts, ascorbyl glucoside, a licorice extract, azelaic acid, α-hydroxyacids (notably lactic acid or glycolic acid), aloesin, gallic acid and its derivatives (notably esters of gallic acid and of hydroflavanols, such as epicatechin-3-O-gallate (ECG), gallocatechin-3-O-gallate (GCG), epigallocatechin-3-O-gallate (EGCG), and epigallocatechin (EGG)), glutathione, glycolic acid, hexyl resorcinol, hydroxystilbene and its derivatives (notably resveratrol (3,4′,5-trihydroxystilbene) and its isomers (oxyresveratrol and methoxyresveratol)).
The preferred whitening agents are α-arbutin and liquorice extract. A liquorice extract is typically selected, for which the concentration of glycyrrhizic acid is greater than or equal to 0.15%, for example the one marketed by Alban Muller International under the trade name Botanical Liquorice PS.
Generally, the composition comprises from 1% to 5% by weight of whitening agent(s) based on the total weight of the powdered composition.
Lightening Agent
The powdered composition according to the invention comprises one or several lightening agents.
A lightening agent gives the possibility of intensifying the radiance and sharpening the hues of the cosmetic compositions comprising them upon application on the skin.
The lightening effect may notably be measured with a chromatometer (colorimeter), in particular by using the CIE Lab L*a*b* method, for example by applying lightening agents on pigmented human epidermises restored in vitro of the MelanoDerm® (MatTek) type. From these values, it is possible to calculate the color (ΔE*) as explained above.
The lightening agent(s) may independently be selected from optical brighteners and mothers-of-pearls (such as borosilicates or natural or synthetic mica (such as synthetic fluorphlogopite), and, said mica being optionally covered with titanium oxide (TiO2), iron oxide (Fe2O3) (red, yellow or black), chromium oxide (Cr2O3), carmine, Prussian blue, ultramarine blue, manganese violet or with their mixtures), silica, alumina and mixtures thereof).
Optical brighteners are lightening agents via an optical route, and are chemical compounds provided with fluorescence properties, which absorb in the ultraviolet (maximum absorption at a wavelength of less than 400 nm) and re-emit energy by fluorescence in the wavelength range comprised between 380 nm and 830 nm. Emission of energy comprised between 400 nm and 480 nm results in an emission in the blue portion of the visible range, which contributes, when this emission occurs on the skin, to visually whitening it.
From among optical brighteners, mention may be made of:
wherein A1 is an aromatic, heterocyclic or alkyl group, and A2 is a hydrogen atom or an alkylene group;
wherein A3 is a heterocyclic group;
wherein A4, A5, A6, A7, B1 and B2 represent independently a hydrogen atom, a group —SO3Na or an alkyl group; and
wherein A8, A9, A12 and A13 represent independently a hydrogen atom, a group —SO3Na or a phenylamino, dialkylamino or morpholino group, and A10 and A11 represent independently a hydrogen atom or a -SO3Na group.
In the formulae (I) to (IV):
The preferred optical brighteners are sodium 4,4′-bis[(4,6-dianilino-1,3,5-triazin-2-yl)amino]stilbene2,2′-disulfonate, 2,5-thiophenedi-ylbis(5-terbutyl-1,3-benzoxazole), sodium di-styryl-20 4,4′-biphenyldisulfonate, and disodium distyrylbiphenyl disulfonate.
Preferably, the lightening agent is natural or synthetic mica (such as synthetic fluorphlogopite), and optionally covered with titanium oxide (TiO2), iron oxide (Fe2O3) (red, yellow or black), chromium oxide (Cr2O3), carmine, Prussian blue, ultramarine blue, manganese violet, silica, alumina or mixtures thereof.
Generally, the composition comprises from 1% to 15% by weight of lightening agent(s) based on the total weight of the powdered composition.
Encapsulant
The powdered composition according to the invention comprises one or several encapsulants.
The encapsulant typically has a melting point comprised between 40° and 50° C.
Generally, the encapsulant is transparent, in order not to modify the white color of the pigment of the powdered composition.
Preferably, an encapsulant is selected for which the viscosity is from 10 cSt to 800 cSt (0.1 cm2.s−1 to 8 cm2.s−1), notably 50 cSt to 200 cSt (0.5 cm2.s−1 to 2 cm2.s−1) at the temperature for preparing the powdered composition (temperature of step a) below) is adapted so that it may easily be introduced into the powdered composition.
The encapsulants may be hydrophilic or lipophilic. A hydrophilic encapsulant will be preferred if the cosmetic composition into which it is desired to introduce the powdered composition is aqueous or is an emulsion. A lipophilic encapsulant will be preferred if the powdered composition into which it is desired to introduce the cosmetic composition is oily or is an emulsion.
Among the hydrophilic encapsulants which may be used, mention may be made of film-forming agents of natural origin from the family of polysaccharides (as an example: alginates, pullulan, sodium hyaluronate, chitin, dextran, carrageenan, chitosan succinamide, galactomannans), esters of waxes and of polyglycerol, or synthetic polymers such as polyethylene glycol, polyacrylic acid, polylactic acid, polyvinyl alcohol, acrylamide, isopropylacrylamide or copolymers thereof.
Among the lipophilic encapsulants which may be used, mention may be made of natural waxes of vegetable origin (for example candelila, carnauba waxes), of animal origin (for example beeswax), of mineral origin or synthetic origin (for example: polyethylene, polypropylene, . . . ).
Are preferred polyethylene glycol, a copolymer of polyethylene glycol, or a natural or synthetic wax. Polyethylene glycol, notably with a molecular mass from 500 to 9,000g.mol−1, in particular between 3,000 and 4,000g.mol−1, is a more preferred encapsulant.
Generally, the composition comprises from 1% to 5% by weight of encapsulant based on the total weight of the powdered composition.
Other Additive
The powdered composition may comprise an additive selected from vitamin B3, vitamin E, a ginseng extract, a red and brown algae extract and mixtures thereof.
These additives have the advantage of giving additional properties to the powdered composition, and therefore to the cosmetic composition into which it will be introduced:
Generally, the composition comprises from 0% to 5% by weight of said additive based on the total weight of the powdered composition.
Water
The powdered composition may comprise water, notably when the encapsulant is hydrophilic.
The water proportion has to be sufficiently small so that the composition remains in a powdered form. Generally, the composition comprises from 0% to 5% by weight of water based on the total weight of the powdered composition.
Proportions of the Components
According to an embodiment, the powdered composition consists of:
According to a second object, the invention relates to the method for preparing the powdered composition as defined above, comprising the step for mixing at least one pigment, at least one encapsulant, at least one whitening agent, at least one lightening agent, optionally one additive as defined above and optionally water.
The mixing of the components of the powdered composition may be applied by simultaneous or separate mixing of the components.
Typically, the method comprises the steps:
When the encapsulant is hydrophilic and the powdered composition comprises water, the water is generally mixed with the encapsulant and the whitening agent during step a).
Preferably, no organic solvent is used in the preparation method according to the invention.
The pigments, whitening agents, lightening agents, encapsulants and additives are generally commercially available.
The invention also relates to the powdered compositions which may be obtained with this method.
According to a third object, the invention relates to the use of the powdered composition for introduction into a cosmetic composition (or for preparing a cosmetic composition), as well as to a cosmetic composition comprising the powdered composition.
The powdered composition according to the invention corresponds to an “all-in-one product” adapted so as to be introduced into a cosmetic composition. The use of the powdered composition is economically advantageous since it is possible to introduce in a single step, the pigment, the whitening agent, the lightening agent and the encapsulant, which leads to a gain in time and may minimize the losses of compounds during production.
The cosmetic composition typically comprises the powdered composition as defined above and at least one cosmetically acceptable excipient. The proportion by mass of powdered composition based on the weight of the cosmetic composition is for example from 1 to 3%.
The cosmetic composition may appear as a monophasic or biphasic lotion, water-in-oil or oil-in-water emulsion, hydrophilic or lipophilic gel or powder.
The cosmetic composition may for example be a hair care product (a hair coloration product, shampoo, conditioner . . . ), a makeup product (a mascara, a foundation, an eye-liner, an eye shadow or a blush, a lipstick, a lip gloss, a nail varnish) or a face or body care product. Preferably, this is a makeup or care product for topical application.
The invention is illustrated by the following examples.
1 kg of distilled water and 2 kg of polyethylene glycol (Carbowax Sentry PEG 1450—Dow Chemicals) (encapsulant) were introduced into a beaker and mixed at room temperature until a limpid solution is obtained. According to an alternative method, the mixture of polyethylene glycol/water was heated to 50° C. until a limpid solution was obtained.
0.6 kg of α-arbutin (DSM Pentapharm) (whitening agent) and 1 kg of liquorice extract (Botanical-Licorice PS—Alban Muller International) (whitening agent) were added and the mixture was stirred until a homogenous solution was obtained.
In a mixer, were introduced 50 kg of titanium oxide (Sensient Cosmetic Technologies) (pigment) and 6 kg of mica (Sensient Cosmetic Technologies) (lightening agent) which were placed with stirring at 45° C. When the mixture of powders reached 45° C., the prepared mixture of distilled water/polyethylene glycol/α-arbutin/licorice extract was added thereto dropwise, and then the mixture was left to homogenize for 3 hours at 45° C.
60 kg of powdered composition were thus prepared.
The powdered composition of Example 1 was introduced into two cosmetic compositions with a proportion of 3% by weight based on the weight of the cosmetic composition. The latter had the composition specified in the following Tables 1 and 2 and were prepared as described hereafter.
The cosmetic preparation 1 was prepared according to the following procedure:
The cosmetic preparation 2 was prepared according to the following procedure:
The whitening effect of the cosmetic composition was demonstrated by carrying out tests in vitro of its depigmenting potential on a human epidermis model over a period of 9 days. The method was based on the measurement of the melanin content and on the coloration of the tissues. The investigation was carried out on pigmented human epidermises restored in vitro of the MelanoDerm™ type, provided by MatTek. This model was obtained by co-cultures of human melanocytes and keratinocytes from Afro-American donors, sown, in order to obtain a 3D epidermal tissue with features (differentiation and pigmentation) close to human skin.
The cosmetic composition containing the powdered composition was applied in an amount of 4-5 mg/cm2 directly on the surface of the epidemises by means of an applicator. After each application, the surface of the tissues was rinsed with a phosphate buffer solution. The tissues were then put back to incubate at 37° C., in an air-CO2 oven. The test formula was applied at D0, D1, D2, D5, D6, D7, D8. The melanin content and the coloration of the tissues were analyzed at the end of the treatment (D9). The results obtained with the cosmetic composition containing the powdered composition was compared with those obtained with:
The coloration of the epidermises was measured at DO (before applying the test element) and 24 hours after the last application by means of a chromatometer. In particular, the parameters L*, which indicate the brightness, and a* and b*, which indicate the color sense, were measured. From these values, it was possible to calculate:
ITA°=[Atan (L*−50)/b*]×180/π
ΔE*=√{square root over ((ΔL*)2+(Δa*)2+(Δb*)2)}{square root over ((ΔL*)2+(Δa*)2+(Δb*)2)}{square root over ((ΔL*)2+(Δa*)2+(Δb*)2)}
In order to evaluate the melanin content, at the end of the tests, the tissues were heated for 45-60 minutes to 100° C. in a solubilizing base (Solvable™). After cooling the extracts and centrifugation, the absorbance of the solutions was read out at 405 nm by means of a microplate reader. A standard range consisting of synthetic melanin was incubated at 100° C. for the same period of time as that of the cell extracts, which allows transformation of the optical densities (O.D405) into melanin units (μg/ml).
The results of coloration of the epidermis (ΔITA° and ΔE*) and of depigmenting activity (D.A. %) are summarized in the following table:
The depigmenting activity was calculated according to the formula:
D.A. %=[(Melanincontrol−Melanintreated)/Melanincontrol]*100
wherein Melanincontrol and Melanintreated respectively represent the melanin concentrations in the control sample and in the sample treated with a whitening cosmetic composition. These results demonstrate that the application of different cosmetic compositions lead to a decrease in the coloration of the tissues, to whitening of the skin as well as to a reduction in the melanin content.
The powdered composition of Example 1 also gives the possibility of obtaining better tissue viability as compared with a commercial whitening agent. Cutaneous acceptability was evaluated by a MTT test. For both cosmetic preparations containing the powdered composition and the ingredients introduced separately, the depigmenting effect is not related to a cytotoxic effect since the viability of the tissues is not modified. On the other hand, the Melanex Trio preparation induces slight lowering (25%) of the MTT response of the tissues.
| Number | Date | Country | Kind |
|---|---|---|---|
| 13 51935 | Mar 2013 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2014/054073 | 3/3/2014 | WO | 00 |
