System and method for treating the nails

Abstract

A system for treating nails, comprising: a pulse light emission device (1) making it possible to expose at least one nail to be treated to at least one light pulse, even better to a burst of light pulses, at least one coating (16) to be applied to the nail or nails, absorbing the light emitted by the device, or an applicator of such a coating, notably of reflectivity less than 50% and/or transmissivity less than 50%, and the surface temperature of which can exceed 60 C., and more preferentially 200 C., under the effect of the light emitted by the device.

Claims

1. A system for treating nails, comprising: a pulse light emission device making it possible to expose at least one nail to be treated to at least one light pulse, at least one coating, or an applicator of such a coating to be applied to the nail or nails, absorbing the light emitted by the device and the surface temperature of which can exceed 60 C. under the effect of the light emitted by the device.

2. The system as claimed in claim 1, the coating being of transmissivity less than or equal to 20%.

3. The system as claimed in claim 1, the coating comprising a film of dark color.

4-8. (canceled)

9. The system as claimed in claim 1, the pulsed light emission device being configured to emit a burst of light pulses at a frequency lying between 0.5 and 20 Hz, each pulse exhibiting a fluence such that, given the distance separating an output window of the coating device during use, it lies between 0.5 and 5 J/cm.sup.2 on the coating surface.

10. The system as claimed in claim 1, the device emitting substantially between the wavelengths of 675 nm and 1200 nm, the system comprising a pair of protective goggles or a protective mask for the operator, comprising a filter absorbing the light emitted by the emission device having a transmission factor less than or equal to 1% above approximately 650 nm.

11. The system as claimed in claim 1, comprising a support for maintaining an output window, through which the light leaves the device, at a predefined distance from a reception surface of the nail to be treated.

12. The system as claimed in claim 11, the support comprising a soleplate defining the reception surface, and a raised part under which the foot can be fitted, provided with at least one aperture under which at least one of the nails can be disposed an optical head being disposed in or above the aperture.

13. The system as claimed in claim 1, comprising a tubular end-fitting having an internal surface that is at least partially reflective, the end-fitting being fixed at one of its ends to the output window of an optical head of the device and comprising, at its other end, a zone for receiving at least one digit such that the nail of this digit is positioned to receive the light emitted by the optical head.

14-33. (canceled)

34. A method for improving the appearance of at least one nail, comprising the step of applying to the nail a coating absorbing the light emitted during the treatment, of positioning an output window of a light pulse emission device relative to the nail such that the light emitted by the device is directed toward the nail, and of subjecting the duly coated nail to at least one pulse so that the temperature measured at the surface of the coating can reach at least 60 C. for a duration of at least 0.1 s.

35. The method as claimed in claim 34, the coating having a reflectivity less than 50%.

36. The method as claimed in claim 34, the coating having a transmissivity less than 50%.

37. The method as claimed in claim 34, the coating resisting a temperature of at least 60 C.

38. The method as claimed in claim 34, wherein a reflecting coating is applied to the periphery of the nail.

39. The method as claimed in claim 34, the absorbent coating being composed of a preformed film.

40. The method as claimed in claim 39, the film being precut substantially to the format of the nail to be treated, or of a part of the nail to be treated.

41. The method as claimed in claim 34, comprising the step of abrading the surface of the nail to be treated prior to the application of the absorbent coating.

42. The method as claimed in claim 34, comprising the step of using a support such that the coating is situated at a predefined distance between 1 and 6 cm from the light output window.

43. The method as claimed in claim 34, wherein a protective screen is disposed on top of the skin of the digit.

44. The method as claimed in claim 34, wherein the nail is subjected to a number of pulses between 2 and 20,

45. The method as claimed in claim 44, wherein after the emission of a burst, the nail is left to cool for a duration of at least 30 s.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0099] The invention will be better understood on reading the following detailed description of nonlimiting exemplary implementations thereof, and on studying the attached drawing, in which:

[0100] FIG. 1 schematically represents an example of treatment device according to the invention,

[0101] FIG. 2 represents a schematic and partial cross-section of a nail provided with a coating according to the invention,

[0102] FIG. 3 illustrates the positioning of the nail under the light output window,

[0103] FIG. 4 is a block diagram illustrating different steps of the treatment method according to the invention,

[0104] FIG. 5 illustrates the sanding of the nail,

[0105] FIG. 6 illustrates the protection of the cutaneous environment of the nail,

[0106] FIG. 7 illustrates the protection of the digit,

[0107] FIG. 8 represents a set of masks for producing the coating on the nail,

[0108] FIG. 9 illustrates the possibility of superposing several pieces of film on the nail,

[0109] FIG. 10 represents an example of support with which the treatment head can be equipped,

[0110] FIG. 11 illustrates the propagation of the heat in the nail, at different distances from the surface, as a function of time,

[0111] FIG. 12 represents a variant support,

[0112] FIG. 13 represents a so-called SFL emission spectrum of a pulsed polychromatic light emission treatment device,

[0113] FIG. 14 represents an example of transmission spectrum of blue goggles suited to an IPL treatment device having the SFL spectrum of FIG. 13,

[0114] FIGS. 15a and 15b represent different partial and schematic views of an end-fitting with which the optical head of the device can be equipped.

DETAILED DESCRIPTION

[0115] FIG. 1 represents a light pulse emission treatment device 1, comprising a base station 2, provided with a user interface 3, and a treatment head 4 (also called handpiece) linked by a flexible cable 5 to the base station.

[0116] The device 1 is for example an IPL-type pulsed light machine, the treatment head 4 comprising at least one flash lamp. The machine can be specific to the treatment of the nails, or parameterizable and have other applications, for example depilation.

[0117] Goggles 6 can be used jointly with the machine, in accordance with the teaching of the application EP15738647.5 in the name of the applicant.

[0118] The light emitted can have the spectrum illustrated in FIG. 13, and the goggles 6 can have the spectral transmission factor of FIG. 14.

[0119] That allows the operator using the device not to be dazzled by the light emitted, and thus be able to easily control the application of the light during the implementation of the treatment.

[0120] The treatment head 4 can contain the flash lamp or lamps, as is the case conventionally for a machine of IPL type.

[0121] The treatment head 4 has an optical guide 7, one end of which defines a light output window 8, as illustrated in FIG. 3. The nail O to be treated is placed under this output window 8, with a distance d between the nail and the output window for example of between 3 and 6 cm.

[0122] In accordance with the invention, a coating 16 that significantly absorbs the light emitted by the output window 8 covers the nail. This coating preferably exhibits a reflectivity less than 50% and/or a transmissivity less than 50%, so as to heat up significantly under the effect of the light flashes.

[0123] This coating 16 is preferably composed of a film of an opaque plastic material that is resistant to heat, for example a polyimide (Kapton) or PTFE, of black color. This film can be adhesive or adhere to the nail electrostatically. The transmissivity measured on the Joules-meter is for example 13% for polyimide and 6% for PTFE, for given films of black color, suited to the implementation of the invention.

[0124] The nail treatment method comprises, as illustrated in FIG. 4, a first step of preparation of the nail to reduce its thickness and smooth its surface. This operation is for example performed using a grinder 15 of a handheld tool, as illustrated in FIG. 5.

[0125] Next, in the step 22, the coating 16 is applied to the nail.

[0126] A coating 16 in the form of a patch precut to the form of the nail, supplied on an antiadhesive support 18, as illustrated in FIG. 8, is for example used.

[0127] The support 18 can bear patches 16 of different formats, to adapt to the size of the nail. Some patches may correspond to only a part of the surface of the nail, which is the case for example of the patches 16a and 16b. Two patches can be positioned on the nail with an overlap between them, as illustrated in FIG. 9. In this case, it can be begun by positioning a patch starting from one edge of the nail, then the other patch is positioned starting from the opposite edge, and glued onto the first in the overlap zone.

[0128] Once the nail O to be treated is provided with the absorbent coating 16, in the step 23, the skin in its region in contact with the nail around the latter can be protected, by depositing a reflective coating 17 on the skin, as illustrated in FIG. 6. This coating 17 is for example a water-dispersible white ink, applied by means of an applicator 18, for example of applicator tip type.

[0129] It is also possible to protect a part of the skin of the digit using a white sheet 19 of a flexible material, as illustrated in FIG. 7.

[0130] The light treatment takes place in the step 24, and consists in exposing the coating to one or more bursts of flashes in the example considered. At the end of each burst, the user can feel the heat brought to the nail. The step 24 can be repeated as indicated above. During the treatment, the nail is preferably maintained at a predefined distance from the light output window of the treatment head 4, for example using a shim interposed between the digit and the handpiece, or, better, a dedicated support, as detailed hereinbelow.

[0131] Next, a last step 25 can consist in removing the coating 16, for example by peeling, as well as the white coating, by washing the digit.

[0132] This last step can take place in situ or in the home of the person treated, if appropriate.

[0133] FIG. 10 represents an example of support 30 intended to maintain the light output window at a predefined distance from the nails of the feet. It has a soleplate 34 defining a reception surface for receiving the foot, and a raised part 35 linked to the soleplate 34 and under which the foot is fitted, provided with an aperture 31 positioned above the nail or nails to be treated, for the passage of the light emitted by the head 4 of the device to the nail or nails. The aperture 31 can have a form that makes it possible to engage the optical guide 7 of the head therein, while maintaining the latter at a predefined distance from the soleplate 34. In the example illustrated, the aperture 31 is reniform, and can guide the optical conduit of the head 4 of the device in a scanning movement over the nails of the feet. For example, the operator begins the treatment in proximity to one end of the aperture 31, treats one or two nails, then displaces the conduit in the guide to treat the subsequent nail or nails.

[0134] One or more interdigital separators 32 can be used, if necessary, by being disposed between the toes.

[0135] The support can, if appropriate, be arranged to be fixed removably onto the treatment head 4, for example by a snap-fitting, guide way or other link, for example by screwing.

[0136] As an example, FIG. 12 represents an example of such a support 40. It can be seen that this support 40 can comprise interdigital separators 32.

[0137] The device according to the invention can also comprise an end-fitting 50 making it possible to guide the light to the nail or nails to be treated, as represented in FIG. 15a and FIG. 15b.

[0138] The end-fitting 50 for example comprises a thin strap 54 allowing it to be fixed to the optical head 4 of the device, and a tubular body having a reception zone 51 for the digit or digits for which the nail is to be treated. The reception zone for example accommodates one or two digits, depending on their size.

[0139] The reception zone 51 can comprise a concave incurved edge 52 which allows the end-fitting to rest on the digit during the treatment, such that the nail of this digit is positioned to receive the light emitted by the optical head 4. The light is guided from the optical head to the nail through the tubular body, which preferably has a reflective internal surface, white in the example considered.

Example

[0140] A nail affected by a mycosis is prepared by sanding it to reduce the thickness of the nail to 1-2 mm; the sanding can be performed with a nail sander, provided with a single-use abrasive cylinder. The nail can be cleaned with alcohol. Next, a coating is applied consisting of a film of black non-adhesive Kapton onto the nail, and the skin around the nail is protected as described above. The coating can be in the form of two D-shaped patches, disposed so as to overlap on the nail on their rectilinear edges.

[0141] The machine used in this example is of IPL type and emits a polychromatic light with the SFL spectrum of FIG. 13. The operator and the person being treated wear blue goggles, the latter almost totally blocking the radiation emitted by the machine by having the spectral transmission factor of FIG. 14.

[0142] The nail is subjected to two successive bursts of flashes at a frequency of 3 Hz. Each burst comprises 14 flashes of 4 J/cm.sup.2 each at the output of the head, which is situated at a distance of 3 cm from the nail. The total duration of each burst is approximately 5 s. The two bursts are spaced apart by approximately 2 mn. The fluence on the coating is approximately four times lower than at the output of the head, i.e. approximately 1 J/cm.sup.2. The average surface power on the coating is approximately 3 W/cm.sup.2. The surface temperature of the coating, measured with a thermal camera, exceeds 200 C. for approximately 0.2 s, at the end of the burst.

[0143] The photo-thermal effect has three phases. There is, first of all, conversion of the light into heat at the surface of the coating, then transfer thereof into the interior of the tissues, and finally a biological and cellular reaction. The coefficient of spectral absorption of the irradiated surface, associated with the emission spectrum of the source, determines the percentage of photons absorbed and converted into heat. The transfer of the heat is performed by thermal conduction.

[0144] The heat is propagated from the surface of the coating according to a wave, as FIG. 11 illustrates. In this figure, the temperature is represented as a function of time, for different depths from the surface of the nail.

[0145] It can be seen that, at the surface of the nail, on contact with the coating, the temperature increases very quickly after the flashes to reach almost 180 C., then decreases because of the diffusion of the heat in the material of the nail (curve A). With increasing distance from the surface of the nail, the curve becomes wider and the maximum temperature decreases (curve B). At the interface between the nail and the underlying tissue (curve C), the maximum temperature is approximately 70 C., which is insufficient to cause a burn given the duration for which this temperature is reached, but sufficient to destroy the germs responsible for the mycosis, located in the thickness of the nail and under the nail.

[0146] The invention, with the preparation of the nails that it involves, makes it possible to considerably improve the treatments of the nails by light, by making it possible to work within hitherto unachieved temperature/time pairing zones, notably higher temperatures for shorter times.

[0147] However, the invention also makes it possible to treat the nails with maximum surface temperatures of the coating that are lower and for longer times, the drawback of longer treatment being offset by the possibility of using a treatment device having lower light power and fluence.

[0148] Obviously, the invention is not limited to the use of a flash lamp IPL machine and it is also possible to use a laser or any other suitable source as light source.

[0149] It is also possible to use other types of coatings absorbing the light emitted during the treatment, for example applied in the form of a heat-resistant opaque varnish.