Electroporation process for delivering a composition comprising at least one hydroxyacid compound

Abstract

Electroporation process for delivering a composition comprising at least one hydroxyacid compound. The present invention relates to an electroporation process for delivering a composition through human keratinous materials, the composition comprising at least one hydroxyacid compound, the electroporation process comprising exposing the composition in contact with said keratinous materials to pulse trains of a pulsed electric current, the pulsed electric current being supplied by an electroporation device having at least one electrode and at least one counter-electrode, the pulse trains of the pulsed electric current repeating at a frequency between 0.1 Hz and 1 kHz, each pulse train having a duration (Ton) between 0.001 s and 2 s, and the pulsed electric current having a voltage amplitude from 20 V to 250 V and an intensity from 0.1 mA to 10 mA. Figure for the abstract: Figure 1

Description

Title of the invention: Electroporation method for delivering a composition comprising at least one hydroxyacid compound Technical field

[0001] The present invention relates to the field of care of keratin materials, in particular the skin.

[0002] For the purposes of the present invention, the term “keratin materials” is intended to denote in particular the skin, the lips and / or the eyelashes, in particular the skin and / or the lips, and preferably the skin of the body and / or the face, and more preferably of the face.

[0003] Nowadays, there are many treatments, some of which are cosmetic surgery or not, that can enhance the appearance of human beings. These treatments, subsequently referred to as aesthetic treatments, can act in many ways, and for example consist of making certain skin imperfections disappear or mask them, or even reducing or even eliminating the signs of aging.

[0004] As an illustration and not a limitation of such treatments, chemical peels may be mentioned in particular.

[0005] The term "peeling" is classically used to refer to a treatment which consists of causing, topically, a destruction of the cellular layers forming the epidermis, to a variable depth depending on the intensity of the peeling, so as to induce an exfoliation of these layers, then their regeneration, that is to say their replacement by new cellular layers. Conventional chemical peels thus revitalize the surface of the skin by creating a uniform and controlled excretion of skin cells.

[0006] Peels advantageously allow the skin to be rejuvenated and retextured and a number of imperfections present on the surface of the skin to be eliminated, such as acne, sun damage, pigment spots, wrinkles and fine lines, superficial scars, dullness, etc. Prior art

[0007] Chemical peels can be performed at home or by professionals, and often include the same active ingredients, such as alpha hydroxy acids.

[0008] However, home peels are less powerful and therefore less effective than professionally administered peels, particularly because they can only affect the most superficial layers of the skin.

[0009] As a result, home peels often provide minimal results, usually requiring several uses before achieving noticeable effects.

[0010] Furthermore, it is known that the application of an electric current to the skin can promote the penetration of an active ingredient. It is thus known to treat human keratin materials using electroporation devices. Electroporation allows the diffusion of active ingredients through the skin thanks to electrical stimulation in a non-invasive manner.

[0011] Electroporation permeabilizes the surface of the skin, allowing the active ingredients to pass through by diffusion, or even by electrophoresis when they are charged.

[0012] Applications US 2010 / 255079, US 2012 / 065575, US 2013 / 345307, US 2013 / 345661, WO 2010 / 112708 or WO 2008 / 045272 describe devices which combine electric current with cosmetic active ingredients. However, these devices are sometimes not yet effective enough, in particular to increase the performance of home peeling formulas. Statement of the invention

[0013] There therefore remains a need to further improve the processes which promote the penetration of active ingredients through keratin materials in order to increase the effectiveness of electroporation, and to benefit from a treatment process, in particular cosmetic or dermatological, of keratin materials, making it possible to increase the performance and accelerate the action of peeling formulas by increasing the supply of peeling active ingredients inside the living part of the keratin materials, while being able to be used comfortably and in complete safety.

[0014] In particular, there is interest in at-home peels that are virtually as effective and powerful as professionally performed peels, to target deeper levels of the dermis at home and to treat, in particular, moderate to severe wrinkles, sun damage and pigmentation, and which can provide results that become apparent immediately or shortly after a single treatment, painlessly and without electroporation-induced muscle contraction.

[0015] There is a need to increase the cutaneous release of active ingredients in a targeted manner within the living parts of keratin materials, and their bioavailability, in order to have effective peels at home.

[0016] The invention aims to meet all or part of these needs. Summary of the invention

[0017] Thus, according to a first of its aspects, the present invention relates to an electroporation method for delivering a composition through human keratin materials, the composition comprising at least one hydroxyacid compound, the electroporation method comprising exposing the composition to contact with said keratin materials to pulse trains of a pulsed electric current, the pulsed electric current being supplied by an electroporation device having at least one electrode and at least one counter-electrode, the pulse trains of the pulsed electric current repeating at a frequency (f^) of between 0.1 Hz and 1 kHz, the pulse trains each having a duration (Ton) of between 0.001 s and 2 s, and the pulsed electric current having a voltage amplitude ranging from 20 V to 250 V, better still from 30 V to 250 V, and an intensity ranging from 0.1 mA to 10 mA.

[0018] The method according to the invention makes it possible to carry out peels at home which are much more effective than conventional home peels, with results which become apparent immediately or shortly after a single treatment.

[0019] Indeed, the cutaneous release of hydroxyacid compounds inside the living parts of keratin materials, as well as their bioavailability, are increased, compared to conventional home peels, in a painless manner and without muscular contraction induced by electroporation.

[0020] According to a preferred embodiment, the method comprises a topical application of the composition to the area to be treated before the application of the pulsed electric current and / or during said application. Detailed description

[0021] As indicated above, the electroporation method according to the invention comprises exposing a composition in contact with said keratin materials, preferably the skin, to trains of electrical pulses of a pulsed current, the latter being delivered by an electroporation device having at least one electrode and at least one counter-electrode.

[0022] According to the invention, the pulse trains of the pulsed current are repeated at a frequency (f^n) of between 0.1 Hz and 1 kHz, the pulse trains each having a duration (Ton) of between 0.001 s and 2 s, and the current having a voltage amplitude ranging from 20 V to 250 V, and an intensity ranging from 0.1 mA to 10 mA. Electroporation device

[0023] According to the invention, the pulsed electric current is supplied by an electroporation device having at least one electrode and at least one counter-electrode.

[0024] Preferably, the pulse trains are repeated at a frequency f^n which ranges from 0.1 Hz to 1 kHz, preferably from 0.3 Hz to 100 Hz, and more preferably is equal to 0.4 Hz + / - 20%.

[0025] According to the invention, the pulsed electric current has a voltage amplitude ranging from 20 V to 250 V, better still from 30 V to 250 V, and even better still from 30 V to 100 V, and an intensity ranging from 0.1 mA to 10 mA. The amplitude is measured peak to peak and the intensity is the instantaneous intensity.

[0026] The frequency of the pulses within the pulse train is greater than the frequency at which the pulse trains are repeated. The voltage may vary within the pulse train around an average value Vmoy of non-zero voltage amplitude, in particular negative, this average voltage Vmoy preferably remaining substantially constant during the duration Ton of the pulse train. The voltage may in particular vary within the pulse train at a frequency (fpulse) of the pulses within the pulse train of between 5 kHz and 100 kHz, better still between 10 kHz and 50 kHz, for example between 30 and 40 kHz.

[0027] The deltaV amplitude of variation of the voltage within the pulse train around the average voltage value Vmoy corresponds for example to less than 50% of the value of this average voltage (in absolute value), or even to less than 30%.

[0028] Preferably, the pulsed electric current has a direct polarity (“DC current” in English), the polarity of the electrode being in particular negative relative to that of the counter-electrode.

[0029] The maximum current density per pulse may be less than or equal to 5 x 10 4 A.

[0030] The pulses may be unipolar, meaning that the current moves in one direction. The pulse train may have a constant maximum amplitude Vmax. The pulse train may have a variable amplitude, for example increasing from a minimum amplitude, reaching the maximum amplitude, and then possibly decreasing towards the minimum amplitude.

[0031] A pulse train may combine two or more pulse waveforms simultaneously or alternately. Applying current may include generating a pulsed current having sinusoidal waveforms, non-sinusoidal waveforms, periodic square waveforms, rectangular waveforms, sawtooth waveforms, spike waveforms, bell waveforms, trapezoidal waveforms, triangular waveforms, or combinations thereof.

[0032] Preferably, the pulsed electric current has a general square or rectangular waveform. In particular, during a pulse train the average voltage may be equal to a negative Vmoy value, and between two pulse trains (during Toff) the voltage is zero.

[0033] A pulse train may comprise from 2 pulses to 15000 pulses, each of duration tpUke.

[0034] Preferably, the pulse trains of the pulsed electric current each have a duration (Ton) ranging from 0.01 s to 3 s, preferably from 0.05 s to 2 s, and more preferably from 0.5 s to 2 s.

[0035] According to a preferred embodiment, the pulse trains are separated by an in pulse-free interval (Toff) ranging from 0.01 s to 3 s, preferably from 0.03 s to 2 s, and more preferably from 0.5 s to 2 s.

[0036] According to a preferred embodiment, the pulsed electric current has a duty cycle (Ton / (Ton+Toff)) varying from 20% to 90%, preferably from 25% to 80%, where Ton denotes the duration of a pulse train and Toff the interval between two successive pulse trains.

[0037] Preferably, the maximum voltage between the electrode and the counter-electrode in open circuit ranges from 20 V to 250 V. Electrodes

[0038] According to a preferred embodiment, the method comprises the step of manually moving the electrode(s) of the electroporation device over the keratin materials while subjecting the latter to said pulsed electric current pulse trains.

[0039] According to another embodiment, the active electrode is stationary and applied to a single location on the keratin materials, for example through an adhesive.

[0040] The electrode(s) may have a rounded surface for contact with keratin materials.

[0041] Preferably, the surface area of ​​the electrode(s) in contact with the keratin materials varies from 2 to 20 cm2, and preferably from 2 to 10 cm2.

[0042] Preferably, the counter-electrode is static and has a surface area in contact with the human keratin materials greater than that of the electrode, which is moved in contact with the keratin materials, the surface area of ​​the counter-electrode preferably being greater than 1.5 times that of the electrode.

[0043] The electroporation device may comprise at least one reservoir containing an effective amount of a composition according to the invention.

[0044] In particular, the device may comprise at least one electrode and one or more compositions stored in a reservoir such as a cavity, a gel, a laminate, a membrane, a porous structure, a matrix or a substrate.

[0045] More particularly, the device may comprise at least one active electrode electrically coupled to a reservoir containing a cosmetic composition according to the invention.

[0046] The reservoir may comprise any shape or material used to retain a composition according to the invention.

[0047] The reservoir may comprise one or more ion exchange membranes, semi-permeable membranes, porous membranes or gels capable of retaining at least temporarily a composition according to the invention.

[0048] The reservoir may comprise one or more cavities formed by a structure.

[0049] In particular, the electroporation device may comprise one or more ion exchange membranes which can be positioned to serve as a polarity selective barrier between the reservoir of composition according to the invention and a biological interface.

[0050] The reservoir may be a hollow imprint at the end of the electrode. Alternatively, according to a particular embodiment, the reservoir is an absorbent material for containing the composition according to the invention.

[0051] The reservoir may in particular be connected to a piston or any other means for dispensing the composition. Thus, the active electrode may be provided with a type of ball applicator powered by a piston. The piston may be actuated during use of the electroporation device.

[0052] The electroporation device may further be an electroporation patch or an electroporation face mask.

[0053] Preferably, the electroporation device is hand-held. User interface

[0054] The electroporation device may include a user interface.

[0055] The user interface may be for inputting data regarding the types of waveforms to be applied as electrical stimuli. The user interface may include an alphanumeric keypad and a display. The alphanumeric keypad may be implemented as a touchscreen.

[0056] The user interface may in particular include directional arrow buttons and an enter button for entering data into a memory.

[0057] Input of wave parameters may be accomplished through the use of text boxes and / or through the use of drop-down menus. Regardless of the manner of data entry, the user interface may communicate a variety of prompts for the user to enter information.

[0058] The user interface may prompt the user to enter the duration of the treatment.

[0059] The user interface may prompt the user to enter the treatment area.

[0060] The device may include a controller that executes logic routines to direct the user interface to present the user with appropriate prompts. The controller then uses the input parameters to generate, via its electronics, including, but not limited to, the appropriate voltage based on the parameters entered by the user. Other sensors

[0061] According to a particular embodiment of the electroporation method, the method comprises a step of measuring the temperature of the skin, the impedance of the skin and the pH of the composition.

[0062] Thus, the electroporation device may comprise at least one temperature sensor. temperature, an impedance sensor and / or a pH sensor.

[0063] The application of the current profile can thus be reduced to a safety level when a value measured by one of the sensors exceeds a safety range or value.

[0064] According to a particular embodiment of the electroporation method, the method comprises a step of measuring the pH of the composition. When the measured pH exceeds a pH safety range, the application of the current profile is switched to a safety level, for example a safety level below 1 V, such as 0.5 V. The pH safety range is for example pH 3 to 7. In some embodiments, when the measured pH exceeds a pH safety range, for example the range 3 to 7, the device switches the polarity for a short period to allow the pH to be rebalanced.

[0065] According to a particular embodiment of the electroporation method, the method comprises a step of measuring the impedance of the skin. When the measured impedance exceeds an impedance safety range, the application of the current profile is reduced to a safety level to avoid an undesirable event. The safety level may be less than 1 V, such as 0.5 V. The impedance safety range may be from 5 kΩ to 2 MΩ.

[0066] According to a particular embodiment of the electroporation method, the method comprises a step of measuring the temperature of the skin. When the measured temperature exceeds a temperature safety value, the application of the current profile is switched to a safety level, for example less than 1 V, such as 0.5 V. The temperature safety value can be chosen to be less than or equal to 43°C.

[0067] In a preferred embodiment of the electroporation method, the method comprises the steps of: - measurement of skin temperature, - measurement of the impedance of the composition, and - measurement of the pH of the composition.

[0068] The device is configured to process the results and regulate the microcurrent and polarity. Process

[0069] The method according to the invention can be cosmetic and non-therapeutic.

[0070] According to a particular embodiment of the electroporation method, the method comprises the transdermal delivery of a composition according to the invention, comprising one or more hydroxy acid compounds.

[0071] According to a particular embodiment of the invention, the method for delivering the composition according to the invention comprising at least one hydroxyacid compound, in particular salicylic acid, through the keratin materials, comprises the application of a specific pulsed electric current profile, from an electroporation device having at least one electrode and at least one counter-electrode, for a specific duration sufficient to transdermally deliver the hydroxyacid compound(s), in particular salicylic acid, to a biological subject.

[0072] Thus, the diffusion through human keratin materials of the hydroxyacid compound(s), in particular salicylic acid, can be increased by the application of the electroporation method according to the invention. Such an increase in the diffusion of the active ingredient makes it possible to optimize the quantity of active ingredients necessary for the target treatments in the different layers of the keratin materials.

[0073] The electroporation treatment can be applied for a duration of 60 s to 1000 s.

[0074] In particular, the electroporation treatment is applied for a duration of 120 s to 480 s. Kit

[0075] According to a particular embodiment, the invention also proposes an electroporation kit comprising: - an electroporation composition comprising at least one hydroxyacid compound, in particular salicylic acid, and - an electroporation device for implementing the electroporation method as described above.

[0076] The present invention also provides an electroporation kit comprising: - an electroporation composition comprising at least one hydroxyacid compound, in particular salicylic acid, and - an electroporation device for delivering the electroporation composition through the keratin materials, configured to apply a negative pulsed current profile.

[0077] Preferably, the present invention provides a kit for implementing the method as defined above, comprising: - an electroporation device having at least one electrode and at least one counter-electrode and arranged to subject the keratin materials to pulse trains of a pulsed electric current, the pulse trains of the pulsed electric current repeating at a frequency (ftrain) of between 0.1 Hz and 1 kHz, the pulse trains each having a duration (Ton) of between 0.001 s and 2 s, and the pulsed electric current having a voltage amplitude ranging from 20 V to 250 V and an intensity ranging from 0.1 mA to 10 mA, and - a composition comprising at least one hydroxyacid compound, in particular salicylic acid.

[0078] The electroporation device and the composition may be packaged together, for example in the same packaging. Applications

[0079] In a preferred embodiment, the method, composition and kit according to the invention make it possible to treat wrinkles and signs of aging, to improve the softness, quality of the skin and appearance of the skin. It can thus be used to moisturize the skin, to improve the suppleness of the skin, to improve and / or reduce the microrelief of the skin, as well as to combat the signs of skin aging.

[0080] The method, composition and kit according to the invention are particularly effective in delivering anti-aging ingredients that permeate the skin beyond superficial levels, which can contribute to such effects. After ablative laser procedures or chemical peels for example, electroporation can also improve the healing process by achieving a higher delivery of actives. The rapid penetration that reaches a greater depth makes electroporation also effective for acne scars.

[0081] According to another particular embodiment, the method is used to minimize the effects of age on the skin, and / or pigmentation, and / or volume, and / or sagging of wrinkles, and / or tone and / or spots, and / or to improve the firmness, and / or radiance, and / or smoothness of the skin. Description of figures

[0082] Other characteristics, variants and advantages of the invention will emerge from reading the description, from non-limiting examples of implementation thereof, and from examining the appended drawings, in which: Figures

[0083] [Fig-1] [Fig.l] schematically represents an example of a device electroporation according to the invention,

[0084] [Fig.2] [Fig.2] is a block diagram of the device,

[0085] [Fig.3] [Fig.3] illustrates the modulation of the output voltage,

[0086] [Fig.4] [Fig.4] represents an elementary pattern of the output signal,

[0087] [Fig.5] [Fig.5] is a diagram comparing the delivery in kera- salicylic acid from a 2% simplex salicylic acid formulation topically, and delivery of salicylic acid from a 2% simplex salicylic acid formulation by electroporation, and

[0088] [Fig.6] [Fig.6] illustrates the shape of the applied signal in an example.

[0089] [Fig.l] shows an example of a treatment device 1 according to the invention.

[0090] This device 1 comprises at least two electrical outputs between which a signal electricity is generated.

[0091] In the example considered, the device 1 comprises at least one electrode 2, to be moved on the skin in the areas to be treated, and a counter-electrode 3 to be fixed on the body, for example using a bracelet or an adhesive patch.

[0092] The electrode 2 can be carried, as illustrated in [Fig. 1], by a housing 4 which houses an electronic signal generation circuit.

[0093] The electronic signal generation circuit may comprise, as illustrated in [Fig.2], a central unit 11 with a microcontroller, for example of the ATMEGA type, which executes software making it possible to generate a signal of the desired shape, which is amplified by an amplifier 12 connected to the electrode 2 and to the counter-electrode 3.

[0094] The central unit 11 also manages the user interface 13, which comprises for example a display 14 and one or more control buttons 15.

[0095] The electronic circuit can be powered by a battery 16 housed in the housing 4, or alternatively by a mains adapter.

[0096] The output signal can be modulated.

[0097] The output signal may be a periodic signal, of given elementary pattern, which is module.

[0098] For example, the output signal may be a periodic square signal, as illustrated in [Fig.4], which is modulated according to a modulation profile as illustrated in [Fig.3], with a duration Ton during which the periodic signal of frequency fpulse is present, which generates a pulse train, followed by a duration Toff during which this signal is no longer present, this duration Toff preferably being a duration during which the voltage is zero between the electrode and the counter-electrode.

[0099] The duration Ton of a pulse train of the periodic signal is for example between 1 ms and 30 ms, better between 2 ms and 10 ms, being for example of the order of 5 microseconds when the device 1 is used in conjunction with a skin peeling active ingredient, as detailed later. The frequency fpuke of the pulses within the train is for example between 10 kHz and 50 kHz.

[0100] A Ton duration less than or equal to 10 ms can reduce the risk of skin irritation or sensation of pain or induction of muscle contractions, knowing that the nature of the applied field, in particular the geometry of the electrodes and their configuration (very close or very far apart, superficial electric field versus through when the electrodes are far apart), can lead to different perception thresholds.

[0101] A rest period Toff greater than or equal to 100 ms allows the skin to recover a basal membrane potential between the application of the pulses.

[0102] The device 1 can be configured to generate an electrical signal between the electrode and the counter-electrode, during a predefined number of cycles, according to a train of pulses of duration Ton, followed by a duration Toff, without pulses, for example using a pulse or pulse train counter, or for a predefined duration, using a timer.

[0103] The electrode 2 preferably has a rounded shape.

[0104] The contact surface with the skin of the electrode 2 ranges for example from 2 cm2 to 10 cm2.

[0105] The density of electric current applied by the electrode 2 ranges for example from 0.1 mA / cm2 to 0.5 mA / cm2.

[0106] The voltage between the electrode 2 and the counter-electrode 3 preferably increases when a resistive load is connected to them and the resistance of the load increases. The amplitude is for example substantially zero for a zero resistance up to a resistance of 10 kOhms, then increases until reaching around 200 V in open circuit.

[0107] The current (RMS) delivered by the device is preferably between 150 mA and 250 mA when it flows through a resistance whose value varies between 1 kOhm and 500 kOhms.

[0108] The device may be offered to the user with a composition P according to the invention to be applied to the skin, within a common packaging, such as a box for example.

[0109] The composition P according to the invention can be contained in any type of container, for example a container provided with an applicator for applying the composition to the skin, or a pump bottle, among other possibilities.

[0110] Preferably, the applied voltage is unipolar, the voltage of the electrode 2 being for example either always positive or always negative, depending on the nature of the active ingredient(s) contained in the composition. Composition

[0111] An electroporation composition for use in a method electroporation as mentioned above is described.

[0112] A composition according to the invention has a viscosity such that the composition covers both the treated surface and the treatment electrode of the device, allowing fluid and frictionless movement.

[0113] A composition according to the invention preferably has a viscosity of between 0.001 Pa.s and 0.5 Pa.s, better still between 0.005 Pa.s and 0.1 Pa.s, and even better still between 0.01 Pa.s and 0.05 Pa.s.

[0114] The viscosity of the composition is measured at room temperature (25°C) using an RM 200 Plus rheometer (LamyRheology).

[0115] A composition according to the invention may be of the gel type or is an emulsion, in particular a water-in-oil or oil-in-water emulsion, and in particular an oil-in-water emulsion, also known as a direct emulsion.

[0116] According to a preferred embodiment, a composition according to the invention is of gel type, in particular of aqueous gel type.

[0117] A composition according to the invention may comprise an aqueous phase and / or an oily phase.

[0118] In certain embodiments of the electroporation composition, the composition has a pH ranging from 2 to 7.5, preferably from 3 to 6, and more preferably from 3 to 5.

[0119] In some embodiments, when the measured pH exceeds a safe pH range, e.g., the range of 3 to 6, the device switches polarity for a short period of time to allow the pH to rebalance.

[0120] As mentioned above, the electroporation method according to the present invention comprises a step of applying to human keratin materials a composition comprising a hydroxyacid compound. Hydroxyacid Compounds

[0121] Hydroxyacid compound(s), in particular salicylic acid, are known to have one or more beneficial uses in humans, in particular as an anti-aging active ingredient.

[0122] The composition according to the invention comprises one or more hydroxy acids chosen from α-hydroxy acid compounds (AHA), β-hydroxy acid compounds (BHA), lipohydroxy acid compounds (LHA), polyhydroxy acid compounds (PHA), and mixtures thereof.

[0123] Preferably, the composition according to the invention comprises one or more hydroxy acids chosen from α-hydroxy acid compounds (AHA), β-hydroxy acid compounds (BHA), and mixtures thereof, which may in particular be linear, branched or cyclic, saturated or unsaturated. α-Hydroxyacid compounds

[0124] The term "α-hydroxy acid" is understood, according to the present invention, to mean a carboxylic acid having at least one hydroxyl functional group occupying an α position on said acid (carbon adjacent to a carboxylic acid functional group). This acid may be present in the final composition in the form of the free acid and / or in the form of one of its associated salts (salts with an organic base or an alkali metal, in particular), in particular depending on the final pH imposed on the composition.

[0125] More particularly, the α-hydroxy acid compounds are chosen from glycolic acid, oxalic acid, lactic acid, 1-hydroxy-1-cyclopropanecarboxylic acid, 2-hydroxy-3-butenoic acid, 2-hydroxyisobutyric acid, 2-hydroxy-n-butyric acid, isoserine, glyceric acid, 2-hydroxy-3-methylbutyric acid, 2-hydroxy-2-methylbutyric acid, 2-hydroxyvaleric acid, 4-amino-2-hydroxybutyric acid, 1-hydroxycyclohexanecarboxylic acid, fumaric acid, dihydroxyfumaric acid, citramalic acid, tartaric acid, citric acid, 2-hydroxy-4-(methylthio)butyric acid, mandelic acid, 2-hydroxy-3-methylvaleric acid, glyoxyurea, [3-imidazolelactic acid, 2-trifluoromethyl-2-hydroxypropionic acid, 2-hydroxybutanoic acid, 2-hydroxypentanoic acid, 2-hydroxyhexanoic acid, 2-hydroxyheptanoic acid, 2-hydroxyoctanoic acid, 2-hydroxynonanoic acid, 2-hydroxydecanoic acid, 2-hydroxyundecanoic acid, 2-hydroxydodecanoic acid, 2-hydroxytetradecanoic acid, 2-hydroxyhexadecanoic acid, 2-hydroxyoctadecanoic acid, 2-hydroxytetracosanoic acid, 2-hydroxyeicosanoic acid, hexahydromandelic acid, arabic acid, phenyllactic acid, hydroxyphenylglycine, 3-hydroxymandelic acid, 4-hydroxymandelic acid,methylacetic acid, L-arginic acid, 3-methoxymandelic acid, 4-methoxymandelic acid, 3-(4-hydroxyphenyl)lactic acid, tartronic acid, [3-chlorolactic acid, 1-cyclopentanol-l-carboxylic acid, 1,2-dihydroxycyclobutanecarboxylic acid, 2-ethyl-2-hydroxybutyric acid, a-hydroxyisocaproic acid, a-hydroxycaproic acid, 2-hydroxy-3,3-dimethylbutyric acid, malic acid, hydroxytartronic acid, gluconic acid, glucuronic acid, pyruvic acid, galacturonic acid, aleuritic acid, ribonic acid, lactamide, N-methyllactamide, N-ethyllactamide, N,N-dimethyllactamide, N-2-hydroxyethyllactamide, their salts and their mixtures. It is also possible to use mixtures of these different acids.

[0126] More particularly, the following examples of α-hydroxy acids may be cited: citric acid, oxalic acid, lactic acid, glycolic acid, glyceric acid, tartaric acid, malic acid, mandelic acid, methylacetic acid, glucuronic acid, pyruvic acid, phenyllactic acid, arabic acid, gluconic acid, galacturonic acid, hydroxytartronic acid, lactamide, N-methyllactamide, N-ethyllactamide, N-2-hydroxyethyllactamide, and mixtures thereof.

[0127] In particular, the preferred compounds are chosen from glycolic acid, oxalic acid, lactic acid, L-lactic acid, DL-lactic acid, D-lactic acid, malic acid, tartaric acid, DL-glyceric acid, arabic acid, gluconic acid, hydroxytartronic acid, lactamide, N-methyllactamide, N-ethyllactamide, N-2-hydroxyethyllactamide, and mixtures thereof.

[0128] According to a preferred embodiment, the α-hydroxy acid is chosen from citric acid, malic acid, tartaric acid, lactic acid and their salts. More particularly Typically, the α-hydroxy acid is selected from citric acid, lactic acid, their salts and their mixtures. P-hydroxyacid compounds

[0129] The term "[3-hydroxy acid" means, according to the present invention, a carboxylic acid having at least one hydroxyl functional group occupying a [3] position on said acid. This acid may be present in the final composition in the form of the free acid and / or in the form of one of its associated salts (salts with an organic base or an alkali metal, in particular), in particular depending on the final pH imposed on the composition.

[0130] More particularly, examples of [3-hydroxyacid] compounds may be cited: salicylic acid and its derivatives, in particular the derivatives of the following formula (I) or a salt of such a derivative:

[0131] [Chem.l] COOH R3 R2

[0132] in which: - the radical Ri represents a hydroxyl group or an ester of formula: -O-CO-R4, in which R4 is a saturated or unsaturated aliphatic group, containing from 1 to 26 carbon atoms, and preferably from 1 to 18 carbon atoms, an amine or a thiol group which may be substituted with an alkyl group containing from 1 to 18 carbon atoms, and preferably from 1 to 12 carbon atoms, - R2 and R3, independently of each other, are located in position 3, 4, 5 or 6 on the benzene ring and, independently of each other, represent a hydrogen atom or a group -(O)n-(CO)m-R5, where n and m, independently of each other, are each an integer equal to 0 or 1, provided that R2 and R3 do not simultaneously represent a hydrogen atom;R5 represents a hydrogen atom, a linear, branched or cyclic saturated aliphatic group containing from 1 to 18 carbon atoms, an unsaturated group containing from 3 to 18 carbon atoms, carrying one to nine conjugated or unconjugated double bonds, the groups possibly being optionally substituted by at least one substituent chosen from halogen atoms (fluorine, chlorine, bromine or iodine), trifluoromethyl groups, hydroxyl groups in free form or esterified by an acid containing from 1 to 6 carbon atoms, or carboxyl groups, free or esterified by a lower alcohol containing from 1 to 6 carbon atoms. ;

[0133] Preferably, the salicylic acid derivative of formula (I) is such that Ri represents a hydroxyl group, R2 represents a hydrogen atom and R3 is in position 5 of the benzene ring and represents a group -CO-R5 where R5 represents a saturated aliphatic group containing from 3 to 15 carbon atoms.

[0134] According to a preferred embodiment, the salicylic acid derivative of formula (I) is chosen from 5-n-octanoylsalicylic acid, 5-n-decanoylsalicylic acid, 5-n-dodecanoylsalicylic acid, 5-n-octylsalicylic acid, 5-n-heptyloxysalicylic acid, 4-n-heptyloxysalicylic acid, 5-tert-octylsalicylic acid, 3-tert-butyl-5-methylsalicylic acid, 3-tert-butyl-6-methylsalicylic acid, 3,5-diisopropylsalicylic acid, 5-butoxysalicylic acid, 5-octyloxysalicylic acid, propanoyl-5-salicylic acid, 5-n-hexadecanoyl-5-salicylic acid, 5-n-oleoyl-salicylic acid and 5-benzoylsalicylic acid, their monovalent and divalent salts and their mixtures.

[0135] Preferably, the composition comprises at least one [3-hydroxyacid] compound, preferably salicylic acid.

[0136] The hydroxy acid compound(s), in particular the |3-hydroxy acid compound(s), preferably salicylic acid, may be present in the composition according to the present invention in a content of between 0.1% and 15%, preferably between 0.5% and 10%, and more preferably between 1% and 5% by weight, relative to the total weight of the composition. Aqueous phase

[0137] A composition according to the invention preferably comprises an aqueous phase.

[0138] According to a preferred embodiment, the composition according to the present invention has a water content of between 20% and 100% by weight, in particular between 40% and 100% by weight, and preferably between 60% and 100% by weight, relative to the total weight of the composition.

[0139] According to a preferred embodiment, the aqueous phase of a composition according to the invention also comprises at least one alcohol, chosen in particular from monoalcohols and polyols, in particular chosen from glycols.

[0140] Thus, the composition may comprise at least one monoalcohol, preferably chosen from ethanol and isopropanol, and more preferably at least ethanol.

[0141] Preferably, the composition comprises glycerol.

[0142] Preferably, the mass concentrations of monoalcohol(s) are between 0.1% and 30%, and preferably between 5% and 15% by weight, relative to the total weight of said composition.

[0143] The composition may also comprise a polyol chosen from propylene glycol, propanediol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, caprylyl glycol, glycerol and sugars such as sorbitol, (poly)alkylene glycols, and mixtures thereof.

[0144] Preferably, the composition may comprise a polyol chosen from pro-panediol and propylene glycol, and mixtures thereof.

[0145] According to one embodiment, the mass concentrations of polyol vary from 0.01% to 40% by weight, relative to the total weight of said composition.

[0146] Preferably, the mass concentrations of polyol range from 0.1% to 30%, and preferably from 5% to 15% by weight, relative to the total weight of said composition. Thickener / Gelling agent

[0147] According to a preferred embodiment, a composition according to the present invention may comprise a thickener / gelling agent.

[0148] Thus, depending on the viscosity of the composition that it is desired to obtain, one or more thickeners / gelling agents, in particular hydrophilic, i.e. soluble or water-dispersible, can be incorporated into the composition.

[0149] Examples of hydrophilic gelling agents that may be mentioned include modified or unmodified carboxyvinyl polymers, such as the products marketed under the names Carbopol (CTFA name: carbomer) and Pemulen (CTFA name: Acrylates / CiO-3o alkyl acrylate crosspolymer) by the company Goodrich; polyacrylamides; polymers and copolymers of 2-acrylamido 2-methylpropane sulfonic acid, optionally crosslinked and / or neutralized, such as poly(2-acrylamido 2-methylpropane sulfonic acid) marketed by the company Hoechst under the name Hostacerin AMPS® (CTFA name: Ammonium poly-acryldimethyltauramide);crosslinked anionic copolymers of acrylamide and AMPS®, in the form of a Water-in-Oil emulsion, such as those marketed under the name Sepigel 305 (CTFA name: Polyacrylamide / Ci3-i4 Iso-paraffin / Laureth-7) and under the name Simulgel 600 (CTFA name: Acrylamide / Sodium acryloyldimethyltaurate copolymer / Isohexadecane / Polysorbate 80) by the company SEPPIC; polysaccharide biopolymers such as modified celluloses, carrageenans, in particular kappa-carrageenan, gellan gum, agar-agar, xanthan gum, alginate compounds, in particular sodium alginate, scleroglucan gum, guar gum, inulin and pullulan, cassia gum, karaya gum, konjac gum, tragacanth gum, tara gum, acacia gum or gum arabic, and mixtures thereof. The amount of gelling agents depends on the intended purpose. ;

[0150] According to a preferred embodiment, a composition according to the present invention comprises a polysaccharide, in particular chosen from a cellulose or a derivative thereof, in particular cellulose ethers or esters.

[0151] Cellulose derivatives can be anionic, cationic, amphoteric or non-ionic. Among these derivatives, a distinction is made between cellulose ethers, cellulose esters and cellulose ester ethers.

[0152] Among the non-ionic cellulose ethers, mention may be made in particular of alkyl celluloses such as methyl celluloses and ethyl celluloses, hydroxyalkyl celluloses such as hydroxymethyl celluloses, hydroxyethyl celluloses and hydroxypropyl celluloses, and mixed hydroxyalkyl alkyl celluloses such as hydroxypropyl methyl celluloses, hydroxyethyl methyl celluloses, hydroxyethyl ethyl celluloses and hydroxybutyl methyl celluloses.

[0153] Celluloses and derivatives are represented, for example, by the products sold under the names Avicel® (microcrystalline cellulose, MCC) by the company FMC Biopolymers, under the name Cekol (carboxymethylcellulose) by the company Noviant (CP-Kelco), under the name Akucell AF (sodium carboxymethylcellulose) by the company Akzo Nobel, under the name Methocel™ (cellulose ethers) and Ethocel™ (ethylcellulose) by the company Dow, and under the names Aqualon® (carboxymethylcellulose and sodium carboxymethylcellulose), Benecel® (methylcellulose), Blanose™ (carboxymethylcellulose), Culminai ® (methylcellulose, hydroxypropylmethylcellulose), Klucel® (hydroxypropylcellulose), Polysurf® (cetylhydroxyethylcellulose) and Natrosol® CS (hydroxyethylcellulose) by the company Hercule Aqualon.

[0154] According to a preferred embodiment, a composition according to the invention comprises at least one hydroxypropylmethylcellulose and / or one poly(2-acrylamido 2-methylpropane sulfonic acid).

[0155] According to a preferred embodiment, a composition according to the invention comprises at least one hydroxypropylmethylcellulose.

[0156] According to a preferred embodiment, a composition according to the invention comprises at least one poly(2-acrylamido 2-methylpropane sulfonic acid).

[0157] In particular, the amount of thickeners / gelling agents varies for example from 0.01% to 10%, in particular from 0.1% to 5% by weight, preferably from 0.1% to 3% by weight, relative to the total weight of the composition. Oily phase

[0158] As mentioned above, a composition according to the invention may comprise an oily phase.

[0159] When the composition used according to the invention comprises an oily phase, it preferably contains at least one oil, in particular a cosmetic oil. It may also contain other fatty substances.

[0160] Among the oils which may be used in the composition of the invention, mention may be made of hydrocarbon oils of animal origin, hydrocarbon oils of vegetable origin, synthetic esters and ethers, in particular of fatty acids, hydroxylated esters, polyol esters, pentaerythritol esters, linear or branched hydrocarbons of vegetable, mineral or synthetic origin, fatty alcohols and fatty acids containing from 8 to 26 carbon atoms, fluorinated silicone oils and / or par- partially hydrogenated, silicone oils and their mixtures.

[0161] Other fatty substances which may be present in the oily phase are, for example, fatty acids comprising from 8 to 30 carbon atoms, for example stearic acid, lauric acid, palmitic acid and oleic acid; waxes, for example lanolin wax, beeswax, carnauba wax or candelilla wax, paraffin wax, lignite wax or microcrystalline waxes, ceresin or ozokerite, and synthetic waxes, for example polyethylene waxes and Fischer-Tropsch waxes; silicone resins such as trifluoromethyl-(Ci-C4) alkyl dimethicone and trifluoropropyl dimethicone; and silicone elastomers.

[0162] These fats can be chosen in a variety of ways by a person skilled in the art in order to prepare a composition having the desired properties, for example in terms of consistency or texture.

[0163] In particular, the amount of oily phase may vary, for example, from 0% to 30%, and in particular from 0.1% to 15% by weight, relative to the total weight of the composition. Surfactant / Emulsifier

[0164] According to one embodiment, the composition according to the invention may also comprise at least one emulsifier.

[0165] Among the emulsifiers which may be used in the emulsions, mention may be made, for example, of non-ionic emulsifiers such as oxyalkylenated (more particularly polyoxyethylenated) fatty acid esters of glycerol; oxyalkylenated fatty acid esters of sorbitan; oxyalkylenated (oxyethylenated and / or oxypropylenated) fatty acid esters; oxyalkylenated (oxyethylenated and / or oxypropylenated) fatty alcohol ethers; sugar esters such as sucrose stearate; and mixtures thereof, such as the mixture of glyceryl stearate and PEG-40 stearate.

[0166] Mention may also be made of fatty alcohol / alkylpolyglycoside emulsifying mixtures as described in patent applications WO 92 / 06778, WO 95 / 13863 and WO 98 / 47610, for example the commercial products sold by the company SEPPIC under the name Montanov®.

[0167] Among the emulsifiers which can be used in the compositions according to the invention, mention may be made, for example, of alkyl dimethicone copolyols, for example Cetyl PEG / PPG-10 / 1 Dimethicone and more particularly the mixture Cetyl PEG / PPG-10 / 1 Dimethicone and Dimethicone (INCI name), such as the product sold under the brand name Abil EM90 by the company Goldschmidt, or the mixture (Polyglyceryl-4 stearate and Cetyl PEG / PPG-10 (and) Dimethicone (and) Hexyl Laurate), such as the product sold under the brand name Abil WE09 by the same company.

[0168] Mention may also be made of dimethicone copolyols, for example PEG-18 / PPG-18 Dimethicone and more particularly the mixture Cyclopentasiloxane (and) PEG-18 / PPG-18 Dimethicone (INCI name), such as the product sold by the company Dow Corning under the brand name Silicone DC 5225 C or KF-6040 from Shin-Etsu.

[0169] Mention may also be made of non-ionic emulsifiers derived from fatty acids and polyols, alkylpolyglycosides (APG) and sugar esters, as well as mixtures thereof.

[0170] Mention may also be made of succinic-terminated polyolefins, for example succinic-terminated esterified polyisobutylenes and their salts, in particular diethanolamine salts, such as the products sold under the names Lubrizol 2724, Lubrizol 2722 and Lubrizol 5603 by the company Lubrizol or the commercial product Chemcinnate 2000.

[0171] According to a preferred embodiment, the composition according to the invention comprises at least one non-ionic emulsifier.

[0172] The total amount of emulsifiers in the composition will preferably be, in the composition according to the invention, in active material contents ranging from 0% to 8% by weight, and more particularly from 0.5% to 6% by weight, relative to the total weight of the composition. Base

[0173] In embodiments of the electroporation composition, the composition may further comprise at least one base.

[0174] The base may be selected from inorganic bases, for example alkali metal hydroxides, sodium hydroxide, potassium hydroxide, ammonium hydroxides, ammonia, organic bases, for example monoethanolamine, diethanolamine, triethanolamine, triisopropylamine, tris[(2-hydroxy)l-propyl)]amine, N,N-dimethylethanolamine, 2-amino 2-methyl 1-propanol, 2-amino 2-methyl 1,3-propanediol, triethylamine, 1a dimethylamino-propylamine and amphoteric bases (i.e. bases having both anionic and cationic functional groups), such as primary, secondary, tertiary or cyclic organic amines, and amino acids. Examples of amphoteric bases include glycine, lysine, arginine, taurine, histidine, alanine, valine, cysteine, trihydroxymethylaminomethane (TRISTA), triethanolamine, and any mixtures thereof.

[0175] According to a particular embodiment, the base of the composition is chosen from sodium hydroxide, potassium hydroxide, ammonium hydroxides, ammonia, monoethanolamine, diethanolamine, triethanolamine, tro-methamine, and mixtures thereof.

[0176] According to a particular embodiment, the bases of the composition are triethanolamine and sodium hydroxide.

[0177] According to a particular embodiment, the base of the composition according to the invention is present in a concentration by weight of less than 0.5% by weight, or even less at 0.3% by weight, relative to the total weight of the composition.

[0178] The total amount of base(s) in the composition will preferably be, in the composition according to the invention, in contents ranging from 0.1% to 5% by weight, and more particularly from 0.2% to 3% by weight relative to the total weight of the composition. Other additives

[0179] The cosmetic composition may also comprise at least one additive chosen from adjuvants typical of the cosmetic field, such as hydrophilic or lipophilic gelling agents, water-soluble or liposoluble active agents, for example anti-aging active agents, film-forming polymers, preservatives, sequestering agents, antioxidants, solvents, perfumes, odor absorbers, pH correctors, and mixtures thereof.

[0180] According to one embodiment, the composition according to the invention may also comprise at least one preservative, preferably disodium EDTA and / or phenoxyethanol.

[0181] According to a preferred embodiment, the composition according to the invention is free of preservatives. Such an embodiment is particularly advantageous when the pH of the composition is low, for example between 3.5 and 4.5.

[0182] A person skilled in the art will take care to choose the optional additional adjuvants and / or their quantity in such a way that the advantageous properties of the composition are not, or not substantially, affected by the envisaged addition. Physiologically acceptable environment

[0183] The composition, in particular the cosmetic composition, according to the invention, comprises a physiologically acceptable medium.

[0184] For the purposes of the present invention, the expression “physiologically acceptable medium” is intended to designate a medium which is suitable for the topical administration of a composition.

[0185] A physiologically acceptable medium generally has no unpleasant odor or appearance and is fully compatible with topical administration. In the present case, when the composition is intended for topical administration, that is to say by application to the surface of the keratin material in question, such a medium is in particular considered to be physiologically acceptable when it does not cause tingling, tightness or redness unacceptable to the user.

[0186] In particular, the composition is suitable for topical application, i.e. application to the surface of the skin, scalp and / or mucous membrane in question. Thus, the physiologically acceptable medium is preferably a cosmetically or dermatologically acceptable medium, i.e. a medium which has no unpleasant odor, color or appearance, and which does not cause the user unacceptable tingling, tightness or redness.

[0187] The composition can then comprise any constituent usually used in the intended application.

[0188] Of course, the person skilled in the art will take care to choose the optional additional compound(s), and / or their quantity, in such a way that the advantageous properties of the compounds according to the invention are not, or are not substantially, affected by the envisaged addition.

[0189] Unless otherwise indicated, the quantities indicated are expressed as a mass percentage. Example

[0190] To test the effect of the device, a sample of human skin is fixed by its periphery on a support, by interposing the counter-electrode of the electroporation device between the inner face of the skin and the support. The electrode of the electroporation device is placed in contact with the outer face of the skin sample. The housing of the electroporation device is immobilized by a support. The support is placed on an orbital shaker, so that the electrode describes a movement on the surface of the skin.

[0191] The device used in this example is the one sold by the company FUSION under the name FUSION MESO XPERT, after deactivation of the LED lighting.

[0192] The frequency with which the pulse trains follow one another is 0.4 Hz, the duration Ton ranges from 0.5 to 2 seconds, the chosen polarity is negative, that is to say that the electrode is at a negative potential with respect to the counter-electrode. The device is used with the most energetic mode. At the level of the voltage plateau of average value Vmoy during the pulse train of duration Ton, the signal presents a variation at a frequency fpuise of the voltage around the average (negative) voltage Vmoy, as illustrated in [Fig.6]. The pulses of frequency fpuke are for example of maximum amplitude deltaV, within the pulse train, this amplitude deltaV being less than or equal to 30% of the voltage Vmoy, in absolute value.

[0193] We see that in the absence of a pulse train, that is to say during Toff, the voltage is zero.

[0194] This corresponds to a Ton / (Ton+Toff) duty cycle of approximately 80% for example.

[0195] In open circuit, the voltage between the electrode and the counter-electrode is approximately 200 V. On the skin, the voltage between the electrode and the counter-electrode is approximately 40 V.

[0196] The cosmetic compositions are applied before the device is put in place.

[0197] Three gel-type cosmetic compositions are prepared according to the following protocol:

[0198] Composition 1: Microbiologically clean deionized water is poured into the 1st phase formulation beaker. Propylene glycol, propane-1,3-diol, triethanolamine, phenoxyethanol and EDTA are added successively. Once the mixture is homogenized, the powdered salicylic acid is added and then everything is mixed with a Rayneri mixer. The AMPS gelling agent is added gradually and then the denatured alcohol last, to prevent evaporation, with stirring until a perfectly homogeneous gel is obtained which is then allowed to de-bubble.

[0199] Compositions 2 and 3: Microbiologically clean deionized water is poured into the formulation beaker in the first phase. Propylene glycol, propane-1,3-diol and phenoxyethanol are added successively. Once the mixture is homogenized, powdered salicylic acid is added and then everything is mixed with a Rayneri. The gelling agent Hydroxypropyl Methylcellulose is added and then the denatured alcohol last, to avoid evaporation, with stirring. The pH is adjusted using soda until a perfectly homogeneous gel is obtained, which is then allowed to de-bubble.

[0200] The compositions have the following formulations (the quantities are expressed by weight, relative to the total weight of the composition):

[0201] [Tables 1] Compounds (INCI Name) Commercial Reference Formulation 1 (% by weight) Formulation 2 (% by weight) Formulation 3 (% by weight) Sodium Hydroxide SODIUM HYDROXIDE 30% / 0.57 0.29 Disodium EDTA Disodium EDTA 0.05 Triethaflolamine Triethanolamine 99% 2.3 / Salicylic Acid SALICYLIC ACID 2 ? 1 Phenoxyethanol SEPICIDE LD 0.5 0.5 5 Hydroxypropyl 1 Methylcellulose METHOCELF 4 M PERSONAL CARE GRADE 1 1 Ammonium Polyacryloyldimethyl Taurate HOSTACERIN AMPS 2. Alcohol denat. DENATURED ETHYL ALCOHOL 10 10 10 Propylene Glycol MONOPROPYLENE GLYCOL UPS 5 5 5 Propanediol ACTIVONOL-3 5 5 5 Water MICROBIOLOGICALLY CLEAN DEIONIZED WATER qs 100 qs 100 qs 100 Comparative example

[0202] On the one hand, compositions 1 to 3 are applied topically and on the other hand, the application of compositions 1 to 3 is combined with electroporation. Results

[0203] The skin is extracted from the experimental system and then analyzed to determine the amount of salicylic acid that has penetrated.

[0204] The results are given in [Fig.5].

[0205] It is demonstrated that thanks to the method according to the invention, the quantity of salicylic acid having penetrated is much higher, compared to the topical application of an identical composition.

[0206] Throughout the description, including the claims, the expression "comprising a" must be understood as being synonymous with "comprising at least one", unless otherwise specified.

[0207] The expressions “between ... and ...”, “includes from ... to ...”, “formed from ... to ...”, and “ranging from ... to ...” must be understood inclusively, unless otherwise specified.

Claims

Claims

1. An electroporation method for delivering a composition through human keratin materials, the composition comprising at least one hydroxy acid compound, the electroporation method comprising exposing the composition in contact with said keratin materials to pulse trains of a pulsed electric current, the pulsed electric current being supplied by an electroporation device (1) having at least one electrode (2) and at least one counter electrode (3), the pulse trains of the pulsed electric current repeating at a frequency (f^) of between 0.1 Hz and 1 kHz, the pulse trains each having a duration (Ton) of between 0.001 s and 2 s, and the pulsed electric current having a voltage amplitude of between 20 V and 250 V and an intensity of between 0.1 mA and 10 mA.

2. Electroporation method according to claim 1, the maximum voltage between the electrode (2) and the counter electrode (3) in open circuit ranging from 20 V to 250 V.

3. Electroporation method according to claim 1 or 2, the pulsed electric current having a duty cycle (Ton / (Ton+Toff)) varying from 20% to 90%, preferably from 25% to 80%, where Ton denotes the duration of a pulse train and Toff the interval between two successive pulse trains.

4. Electroporation method according to any one of the preceding claims, the pulse trains repeating at a frequency f^ ranging from 0.1 Hz to 1 kHz, preferably from 0.3 Hz to 100 Hz, and more preferably equal to 0.4 Hz + / - 20%, the frequency (fpulse) of the pulses within the pulse train being between 5 kHz and 100 kHz, better still between 10 and 50 kHz, for example between 30 and 40 kHz.

5. Electroporation method according to any one of the preceding claims, the pulse trains each having a duration (Ton) ranging from 0.01 s to 3 s, preferably from 0.05 s to 2 s, and more preferably from 0.5 s to 2 s.

6. Electroporation method according to any one of the preceding claims, the pulse trains being separated by a pulse-free interval (Toff) ranging from 0.01 s to 3 s, preferably from 0.03 s to 3 s, and more preferably from 0.5 s to 2 s.

7. Electroporation method according to any one of the preceding claims, the surface of the electrode(s) (2) in contact with the keratin materials varying from 2 to 20 cm2, and preferably from 2 to 10

8. uni. Electroporation method according to any one of the preceding claims, the counter-electrode being static and having a surface area in contact with the human keratin materials greater than that of the electrode, which is moved in contact with the keratin materials, the surface area of ​​the counter-electrode preferably being greater than 1.5 times that of the electrode.

9. Electroporation method according to any one of the preceding claims, consisting of manually moving the electrode(s) (2) of the electroporation device over the keratin materials while subjecting the latter to said pulsed electric current pulse trains.

10. An electroporation method according to any preceding claim, wherein the pulsed electric current is of general square or rectangular waveform.

11. An electroporation method according to any preceding claim, wherein the electroporation device (1) is hand-held.

12. An electroporation method according to any preceding claim, comprising topical application of the composition to the area to be treated before application of the pulsed electric current and / or during said application.

13. An electroporation method according to any one of the preceding claims, the electrode(s) (2) having a rounded surface for contact with keratin materials.

14. Electroporation method according to any one of the preceding claims, characterized in that the composition comprises one or more hydroxy acids chosen from α-hydroxy acid compounds (AHA), β-hydroxy acid compounds (BHA), lipohydroxy acid compounds (LHA), polyhydroxy acid compounds (PHA), and mixtures thereof, and preferably chosen from α-hydroxy acid compounds (AHA), β-hydroxy acid compounds (BHA), and mixtures thereof, which may in particular be linear, branched or cyclic, saturated or unsaturated.

15. Electroporation method according to any one of the preceding claims, characterized in that the composition comprises at least one [3-hydroxyacid] compound, preferably salicylic acid.

16. An electroporation method according to any one of claims preceding, characterized in that the composition comprises at least one [3-hydroxyacid] compound, preferably salicylic acid, in a content of between 0.1% and 15%, preferably between 0.5% and 10%, more preferably between 1% and 5%, relative to the total weight of the composition.

17. Electroporation method according to any one of the preceding claims, characterized in that the composition has a water content of between 20% and 100% by weight, in particular between 40% and 100% by weight, and preferably between 60% and 100% by weight, relative to the total weight of the composition.

18. Electroporation method according to any one of the preceding claims, characterized in that the composition comprises at least one alcohol, chosen in particular from monoalcohols and polyols, in particular chosen from glycols.

19. An electroporation method according to any one of the preceding claims, characterized in that the composition comprises glycerol.

20. An electroporation method according to any one of the preceding claims, characterized in that the composition comprises a thickener / gelling agent.

21. Electroporation method according to any one of the preceding claims, characterized in that the composition has a pH ranging from 2 to 7.5, preferably from 3 to 6, and more preferably from 3 to 5.

22. Electroporation method according to any one of the preceding claims, characterized in that the composition is free of preservatives.

23. Kit for implementing the method according to any one of the preceding claims, comprising: - an electroporation device having at least one electrode (2) and at least one counter-electrode (3) and arranged to subject the keratin materials to pulse trains of a pulsed electric current, the pulse trains of the pulsed electric current repeating at a frequency (1^) of between 0.1 Hz and 1 kHz, the pulse trains each having a duration (Ton) of between 0.001 s and 2 s, and the pulsed electric current having a voltage amplitude ranging from 20 V to 250 V and an intensity ranging from 0.1 mA to 10 mA, and - a composition comprising at least one hydroxyacid compound, in particular salicylic acid.

Images