WO2009147617A1

WO2009147617A1 - A method of diminishing perspiration

Info

Publication number: WO2009147617A1
Application number: PCT/IB2009/052315
Authority: WO
Inventors: Jean-François Grollier; Henri Samain
Original assignee: L'oreal
Priority date: 2008-06-02
Filing date: 2009-06-02
Publication date: 2009-12-10
Also published as: FR2931686A1

Abstract

The present invention relates to a non-therapeutic method of reducing non-pathological perspiration of a region of the human body that includes sweat glands, the method comprising the step consisting in exposing said region to non-destructive electromagnetic radiation of artificial origin having a wavelength llonger than 400nm and of intensity adapted to exert an action: ·on at least one mechanism associated with the production of sweat to give rise to a temporary and non- therapeutic reduction in the activity of the sweat glands, and/or ·on a mechanism associated with the production of odor by certain bacteria present in said region.

Description

A METHOD OF DIMINISHING PERSPIRATION

The present invention relates to treating regions of the body that are liable to be a source of excessive perspiration .

Background

The armpits in particular are the site of discomfort of several kinds, derived either directly or indirectly from perspiration phenomena. Firstly, the presence of water associated with perspiration is generally felt as being disagreeable, and under certain conditions sweat wets garments. On evaporating, sweat leaves behind salts and proteins that give rise to visible traces and/or to disagreeable sensations. Furthermore, odors may develop.

Even when perspiration is moderate and no traces of water can be seen, nor any odor, discomfort can still result from other factors such as rubbing and temperature, made worse by the confined nature of the site.

Other sources of discomfort may be involved, such as epilation or regrowth of hairs and the wearing of certain garments, in particular those presenting a high degree of impermeability. Aluminum salt technology has been widely used to solve or limit some of these problems, but it presents defects. Although it reduces the presence of water and odor, it is not active on other sources of discomfort. Furthermore, for some people, applying a wet composition is felt to be disagreeable because of the sensation of wetness at the time of application. This sensation can be reduced by using compositions having volatile solvents, but the use of volatile solvents at high concentrations also presents drawbacks. Applying a composition to combat perspiration or its effects can also be considered as unsatisfactory because of potential stickiness or traces left on garments. Finally, some people are reluctant to apply compositions repeatedly to the body.

Application US 2006/0210504 discloses a composition including an anticholinergic compound for acting on nerve fibers to prevent the release of acetylcholine to the sweat gland.

Another possible approach that is recommended in certain circumstances consists in injecting botulinum toxin (botox) to obtain an anti-perspiration effect, however making use of injection greatly limits the potential of this approach, which is restricted to hyperhidrosis .

Accessories have also been proposed to avoid certain drawbacks associated with perspiration. For example, applications US 2006/0041987 or US 2006/0015981 disclose patches for applying to the armpit.

JP 2006 043319 A2 describes using UV light to kill the germs that are responsible for odor developing.

None of the existing solutions is entirely satisfactory and there is a need to benefit from novel treatments and devices to combat perspiration and the associated discomfort.

It is known that certain kinds of electromagnetic radiation can interfere with phenomena of cell regeneration and/or with phenomena of sensitivity.

The article Clinical evaluation of the immediate effectiveness of GaAlAs laser on the therapy of Dentin hypersensitivity, by M.S. Noya et al . , J. Appl . Oral Science, 2004, 12(4) 363-6 thus describes a method of treating hypersensitivity of the teeth by 670 nanometers (nm) light at a concentration of about 5 joules per square centimeter (J/cm²) .

The publication Assessment of anti-inflammatory effect of 830 nm laser light using C-reactive protein levels, by A. C. de Freitas et al . , Braz. Dent. J. (2001) 12(3) discloses on pages 187 to 190 associating treatment with 830 nm light at about 5 J/cm² with moderate doses of paracetamol .

The article Phototherapy improves healing of cutaneous wounds in nourished and undernourished Wistar rats, by A. L. B. Pinheiro et al . , Braz. Dent. J. (2004) 15 (special issue) : pp. SI 21-Sl 28 teaches performing treatment with 635 nm light at 20 J/cm².

The publication Infrared laser light further improves bone healing when associated with bone morphogenic proteins : an in vivo study in rodent model, by M. E. Martinez Gerbi et al . , Photomedicine and Laser Surgery, Vol. 26, No. 1, 2008, pp. 55 to 60 discloses performing treatment with 830 nm light at 16 J/cm², in sessions of 4 J/cm². The publication Effectiveness of laser photobiomodulation at 660 or 780 nm on the repair of third degree burns in diabetic rats, by G.C.S. Meireles et al . , Photomedicine and Laser Surgery, Vol. 26, No. 1, 2008, pp. 47 to 54 teaches performing treatment with 660 nm light or 780 nm at 20 J/cm².

The publication Effect of laser therapy on experimental wound healing using oxidized regenerated cellulose hemostat, by L. Prates Soares et al . , Photomedicine and Laser Surgery, Vol. 26,1, 2008, pp. 10 to 13 teaches performing treatment with 685 nm light at

4 J/cm² regularly once every 48 hours (h) for 7 days, and after injecting a biomaterial (Surgicel) .

Patent application US 2006/0058712 discloses a method of treating body odors by reducing sweating by targeting eccrine sweat glands by means of non-uniform temperature profiles, creating lattices of damaged islets formed by irradiating the skin with electromagnetic radiation at a wavelength going from the visible to the far infrared. Patent application WO 2004/037287 describes a device for applying a therapeutic or cosmetic substance to the skin that is capable of acting to reduce body odor and perspiration, the device comprising a source of light irradiation, e.g. emitting light in the range 550 nm to 870 nm, or in the range 800 nm to 2000 nm, assisting said substance to penetrate or to act. Patent application WO 2004/043543 discloses a device enabling light sources to be positioned under the armpits to irradiate them with electromagnetic radiation having a wavelength lying in the range 290 nm to 1350 nm, in order to act on odors or perspiration. Patent US 2002/0169442 Al describes a method of irradiating the skin by electromagnetic radiation for the purpose of curing acne.

The invention seeks to propose a solution that is simple and practical to implement, and that remedies the above-mentioned drawbacks in full or in part.

Summary

In one of its aspects, the invention provides a non- therapeutic method of reducing non-pathological perspiration of a region of the human body that includes sweat glands, the method comprising the step consisting in exposing said region to non-destructive electromagnetic radiation of artificial origin having a wavelength λ longer than 400 nm and intensity suitable for exerting action on at least one mechanism associated with the production of sweat so as to give rise to a temporary, non-therapeutic reduction in the activity of sweat glands, in particular eccrine and/or apocrine sweat glands . The region treated may comprise the armpits or other regions of the body such as the groin, the palm of the hand, or the feet, for example.

The treatment of the invention is non-depilatory and non-depigmenting, and it is not for use with tender skins or in pathological situations, since its purpose is to reduce routine discomfort due to perspiration. The invention acts on the biological sequences involved in the treated portion of the body becoming uncomfortable, in particular on the innervation and the triggering of sweat glands, and it does so without damaging said glands and the surrounding cells and without modifying the size of the pores in the skin of said portion.

The invention may also act on certain bacteria, such as for example Corynebacterium xerosis, that are responsible for producing odor, in particular in the armpits, by disturbing the activity of the bacteria, but without destroying them.

The invention also makes it possible to reduce the sensations of irritation that can be produced by moisture, rubbing, or temperature.

The electromagnetic radiation used in the invention may be of wavelength, in particular of dominant wavelength, lying in the range 550 nm to 10,000 nm, better in the range 600 nm to 4000 nm, better still in the range 800 nm to 1200 nm, e.g. about 870 nm, 1030 nm, or 1060 nm.

The power of the electromagnetic radiation emitted may lie in the range 0.1 milliwatts (mW) to 5 watts (W), better in the range 1 mW to 2 W. The energy received by the treated region may lie in the range 0.0001 J/cm² to 50 J/cm² per 24-hour period, e.g. 0.1 J/cm² to 1 J/cm².

In these wavelength and power ranges in particular, if exposure does not exceed 120 seconds (s) , for example, the temperature of the skin rises by no more than a few degrees, e.g. 2°C to 4°C, thus avoiding disagreeable or painful sensations during treatment.

Results comparable to those obtained by using a conventional anti-perspiration composition containing aluminum chlorhydrate have thus been obtained using irradiation centered on 870 nm, with a spectrum width of 50 nm or less, applying the treatment for 120 s per armpit and without applying any therapeutic or cosmetic composition .

The treated region may be subjected to scanning by said electromagnetic radiation, either manually or automatically. The purpose of the scanning may be to treat a large area and/or to concentrate the radiation on particular zones, in particular on sweat glands. By way of example, the scanning may be performing by changing the orientation of an optical element, e.g. a mirror, and/or by moving an optical head from which the beam exits, e.g. along at least one axis, or indeed along two or three mutually perpendicular axes. When the light beam is of flat cross-section, the scanning may be performed by moving the beam in a direction that is substantially perpendicular to its direction of flattening, for example.

The treatment is performed by causing the electromagnetic radiation to converge under the surface of the skin, e.g. at a depth lying in the range 1 millimeter (mm) to 8 mm, better in the range 2 mm to

6 mm, e.g. about 4 mm, where the density of sweat glands is at its greatest. Convergence may be obtained by optical means and a single source of radiation or by a plurality of sources delivering beams that meet under the surface of the skin.

The radiation may illuminate the entire region for treatment without distinction, or it may be targeted on zones where the probability of finding sweat glands is the greatest, in particular it may be targeted on pores. The targeting may be achieved by applying a material having optical properties that change locally in the presence of water or sebum, which may be localized in the pores. In particular, the material may become less opaque locally by absorbing water or sebum. The exposure to radiation may take place through such a material, thereby enabling more light to pass locally at the pores because of its loss of opaqueness, thereby enabling treatment to be targeted.

The treatment may also be performed by directing the light onto zones where the presence of pores or of perspiration products has been detected optically by means of an appropriate detector and/or image analysis. Light pulses directed to each of the detected pores may be emitted in succession.

The frequency of exposure to the electromagnetic radiation may be greater than or equal to once per week, preferably being regular and at least three times per week, better at least five times per week.

The treatment by means of the radiation may be followed or preceded by the application of a composition on the treated region, as described in detail below.

The invention also provides a method of treating body odor associated with perspiration, in particular armpit odor, the method comprising the step consisting in illuminating the corresponding region of the skin with radiation of wavelength and intensity that are adapted to reduce the activity of sweat glands. The method may include any of the particular features described in detail above.

Treatment devices and kits

In another of its aspects, the invention also provides a treatment device comprising a source of electromagnetic radiation for implementing any one of the above-defined methods. The treatment device may be adapted to illuminate a region of the body, such as the armpits, for example, and to produce a light beam, e.g. a flat beam of width lying in the range 5 mm to 100 mm, for example.

The radiation emitted by the treatment device may converge at a distance lying in the range 1 mm to 8 mm beneath the surface of the skin, better in the range 2 mm to 6 mm. For this purpose, the device may include an optical system enabling the light emitted by the light source to be caused to converge beneath the surface of the skin, e.g. a system comprising one or more lenses.

The treatment device emitting the radiation may be put into contact with the region for treatment, e.g. the armpit, or it may be held at a distance therefrom, without making contact.

The device may be configured so as to be placed on the body, e.g. the armpit. The device may be arranged to be fastened to the body, e.g. under the armpit, or to be fastened to an undergarment or a garment so as to illuminate the region for treatment. This may enable treatment to be prolonged. The treatment device may include means for fastening to the skin, such as straps, suckers, Velcro® fasteners, elastic bands, bandaging, a garment, press- buttons, adhesive, ... . By way of example, Figure 7 shows a treatment device 10 fastened under the armpit by bands 17. The treatment device may also be incorporated in a glove, an insole, or a shoe, or it may be incorporated in a portion of a garment, e.g. the portion located at the armpits. For example, the device may be carried by a shirt, a vest, a bra, a pullover, a jacket, a waistcoat, a coat, or a corset.

The device may be fastened releasably to the garment. Where appropriate, the garment may present a different nature at the armpits, e.g. for the purpose of allowing the radiation emitted by the device to pass. The treatment device may also enable the portion of the body for treatment to be irradiated through a garment .

The treatment device may constitute a portable entity, preferably suitable for holding in one hand, and containing all the elements required for its operation.

In a variant, the component (s) generating the radiation and the component (s) necessary for illuminating the region for treatment are not united in a common casing.

Thus, a device may be provided in at least two portions, e.g. a stationary portion containing the source (s) of radiation and possibly a user interface, e.g. for making adjustments, and a movable portion that is brought up to the region for treatment, and containing the light outlet, e.g. together with an optical system for generating a flat beam. The two portions may be connected together by means of an optical fiber, for example .

The treatment device may also comprise a stationary portion containing an electrical power supply, and an electronic circuit for controlling the radiation source, and a movable component containing the light-generating component (s) .

The treatment device may also comprise a casing serving at least two movable portions for simultaneously treating two regions of the body, e.g. both armpits. In a particular configuration, the treatment device is configured to be worn by day or by night, for example. The treatment device may thus be movable by the user so as to accompany a moving person. By way of example, this can enable the armpits to be treated all day long. In addition to possible movement systems, optionally motorized, for scanning the zone for treatment with the radiation along mutually perpendicular X and Y axes, the treatment device may also be provided with a system for focusing the illumination along a Z axis perpendicular to the X and Y axes, e.g. by moving, optionally under motor control, the radiation source (s) and/or associated optical systems.

The device may be provided with an autofocus system for rapidly focusing the convergence. The autofocus system informs the appliance of the distance between the appliance and the skin, thereby enabling the appliance to recalculate the focusing distance, it being understood that it preferably calculates the focusing distance so that the irradiation rays converge at a certain distance beneath the surface of the skin, advantageously lying in the range 2 mm to 6 mm. The device may be arranged to avoid light leakage, in particular when it is designed to contact the skin, e.g. with the help of a flexible gasket at its interface with the skin.

In another of its aspects, the invention also provides a kit for reducing perspiration of a region of the human body that includes sweat glands, the kit comprising:

^• a device including a source of electromagnetic radiation for implementing the above-defined method; and • a pharmaceutical or cosmetic composition for use together with the treatment of the skin by the device, and presenting action on at least one mechanism associated with perspiration.

The composition may include at least one agent having action on pain and/or inflammatory phenomena, in particular an agent selected from the agents involved with or interacting on the transport of nerve impulses, e.g. transferring nerve impulses at nerve terminations, at the nerve-muscle junction, at motor end-plates, at cholinergic synapses, at post-kerasynaptic receptors, and from compounds having action that is parasympatholytic, or anticholinergic, analgesics, non-steroid antiinflammatories, anti-Cox 2s, and agents having paralyzing or myorelaxing effects. The composition may include at least one compound selected from biomaterials and biocompatible materials, in particular derivatives of hyaluronic acid, derivatives of cellulose, and other glucides and glucide chains, derivatives of collagen or other peptides, such as polylysine or polyhistidine .

The composition may include at least one compound selected from anti-perspiration, astringent, or absorbent agents, in particular salts of aluminum, zirconium, tannins, derivatives of tannic acid, particles of absorbent silica, and porous polymeric particles.

The kit comprising the source of radiation and the composition may be packaged within a common packaging device, e.g. a casing, a box, a bag, a sachet, or a blister pack. The device including the source of radiation may also be secured to the composition packaging device while in use. For example, the composition may be contained in a receptacle with applicator means at one end, and the light source may be designed to emit radiation from an opposite end of the receptacle .

In another of its aspects, the invention also provides a kit comprising:

^• a treatment device including an electromagnetic radiation source for implementing the method of the invention; and

^• a material presenting opaqueness that decreases on absorbing water or sebum, for application to the region for treatment, with illumination taking place through the material. Such a kit may serve to target treatment on pores .

Source of electromagnetic radiation

The radiation received by the treated zone may be optionally-visible light radiation.

The light used may extend in the red and/or infrared zone . The spectrum of the light emitted may also extend and/or present peaks in other wavelength zones, such as light that is blue, green, or yellow.

The radiation preferably presents a large fraction of its energy in a range 550 nm to 10,000 nm, preferably in a range 600 nm to 4000 nm. The spectrum of the radiation as received by the treated region may thus include at least one dominant wavelength in the 600 nm to 4000 nm range, in particular in the near infrared.

The radiation may be produced in various ways, in particular by the laser effect. Various amplifier materials may be used for implementing the cavity within which the laser population inversion takes place.

For example, it is possible to use solid materials such as : • materials for laser diodes or GaAlAs lasers producing wavelengths around 810 nm, 820 nm, 780 nm, 870 nm;

^• GaAs materials, typically producing wavelengths around 900 nm; • InGaAlP materials typically producing wavelengths around 650 nm, in the range 630 nm to 685 nm;

^• ruby type materials, typically producing wavelengths around 690 nm;

• neodymium: YAG type materials, producing wavelengths around 1064 nm;

^• Ho : YAG type materials, producing wavelengths around 2130 nm;

^• Er: YAG type materials, producing wavelengths around 2940 nm; • Alexandrite type materials, producing wavelengths around 720 nm to 800 nm;

^• titanium sapphire type materials, typically producing wavelengths around 846 nm;

^• ytterbium lasers, producing wavelengths around 1030 nm; and

^• erbium lasers, producing wavelengths around 1550 nm.

It is also possible to use liquid materials, for example as in dye lasers producing wavelengths that may lie in the range red to infrared, or certain gases such as CO₂, producing wavelengths in the infrared, or HeNe. The radiation source may also include light-emitting structures such as light-emitting diodes (LEDs) for example .

In particular, the light source used may comprise a plurality of LEDs, e.g. more than ten LEDs disposed side by side, or a matrix of LEDs.

The radiation source may also comprise an incandescent lamp, of the halogen or rare gas type, or a flash lamp, or other systems operating by electrical discharge.

The radiation source, e.g. when a laser, may be used in continuous mode or pulsed mode. Titanium-sapphire, neodymium YAG, ytterbium, and erbium lasers are well suited for emitting light pulses, but other sources produce or may be modulated to produce discontinuous illumination .

The illumination may be controlled electronically (e.g. Q-switch mode) or by discontinuous interruption of the light beam. It is also possible to create light pulses by discontinuous deflection of the light beam under the effect of a mechanical deflector or a deflector controlled by an electronic system.

With a laser in particular, pulse duration may vary from a few femtoseconds (fs) to about 100 milliseconds

(ms) . More preferably, pulses are used having a duration lying in the range 500 fs to 100 nanoseconds (ns) .

The frequency of the illumination may vary from a few tens of kilohertz (kHz) to one or fewer pulses per second.

The mean electrical power of a source of the invention that is converted into light may lie in the range 0.001 mW to 5 W, and preferably in the range 1 mW to 2 W. The illumination need not be distributed uniformly over the treated surface and it need not be continuous over time. As a result, certain zones may receive higher powers, either locally or at certain moments, and other zones may receive lower powers, or even no power.

The user may perform one or fewer applications per day. It is also possible to perform several applications in a day. The term "application" is used to designate a cycle in which a given region is illuminated.

An area comprising 1 square centimeter (cm²) of skin may be illuminated to receive energy at a rate of 0.0001 joules (J) to 20 J per day, and preferably 0.04 J to 4 J per day.

Depending on the power of the source, the duration of exposure may vary from a fraction of a second to several tens of minutes, for example.

In one particular configuration, the appliance is stationary or located on the region for treatment, e.g. the armpits, and it is held in said zone for the necessary duration. The user may wear the appliance during the day or during the night. Under such circumstances, the energy received per day may be greater than 20 J/cm², and may for example reach 50 J/cm² for a period of 24 h.

The light may be concentrated over a few zones within the treated region, e.g. the armpits, as opposed to over the entire treated zones, with the energy that is received locally possibly being high, and certain zones may receive energy of as much as 50 J/cm².

An optical system may be used for focusing or defocusing the light, e.g. at least one lens or microlenses . It is also possible to cause the light from a plurality of sources to converge on a common point.

It is possible to use a diffusing material located on the light path, and in particular next to the skin, for the purpose of spreading the light and evening out local concentrations. In order to adjust the light flux, in particular its section and/or its intensity, it is possible to use a diaphragm system.

In order to adjust the spectral characteristics of the light received by the skin, use may be made of one or more filters, gratings, or prisms. Use may also be made of non-linear optical elements, such as frequency doublers, in order to adjust wavelength either within the recommended wavelength range, or for the purpose of bringing light into the recommended wavelength range.

At least one waveguide, in particular a light guide, may be used to convey the light to the region for treatment from a remote source. For example, the light may be conveyed to the region for treatment, e.g. the armpit, by one or more optical fibers. This can enable relatively bulky optical components or an electronic system for controlling these components to be located away from the vicinity of the armpit, which can be advantageous when it is desired to wear the light source. Optical fibers may also be incorporated in or fastened to a garment or an undergarment in order to convey light to the region for treatment, e.g. the armpits, from a light source worn on the belt, for example . The invention also provides a textile article, a glove, or a shoe, including a treatment device capable of emitting radiation for the purpose of performing treatment of the invention.

Scanning the region for treatment

The region for treatment, e.g. the armpit, may occupy several tens of square centimeters, and it is possible to provide a system for scanning said zone with the light beam. Scanning may be performed by hand, in particular the device used may deliver the light in a beam and the zone may be scanned by moving the appliance more or less perpendicularly to the beam. It is also possible to use a mechanical scanning system, optionally an automatically guided system.

The device used may include motor means for automatically modifying the orientation of the illumination and/or for moving the beam.

The device may move the light source (s) or it may move an optical system for moving the light beams, the optical system comprising one or more optical deflectors, for example.

By way of example, the scanning frequency may lie in the range a few tens of hertz (Hz) to a few hundreds of Hz.

With scanning being performed either manually or mechanically, it is possible during an application either to cover the surface continuously, i.e. so that all points of the skin are subjected at least once to illumination, or else to cover the surface in partial manner, i.e. so that some points are subjected to illumination at least once, while others are not.

Depth of treatment

The method of the invention may be implemented with at least one light beam that is parallel, converging, or diverging.

In a preferred implementation of the invention, a converging light beam is used. The point of convergence is preferably situated beneath the surface of the skin, advantageously at about 1 mm to 8 mm beneath the surface of the skin, and better in the range 2 mm to 6 mm, with the focusing distance being predefined or adjustable. This convergence may be implemented from a single beam emitted by a single source or by directing beams coming from a plurality of respective sources towards a single zone.

With a single beam, it is possible to use a short focal length optical system causing the light rays to converge with a solid angle that is very wide, e.g. a focal length lying in the range 5 mm to 30 mm, e.g. of 1 centimeter (cm) .

Figure 1 of the accompanying drawing is a diagram showing an example of a treatment device 10 including a light source 11 and an optical system 12 enabling the emitted beam to be caused to converge beneath the surface of the skin S at a depth d.

With more than one beam, two or more light beams, if possible parallel beams or beams that converge, can be caused to converge on a common zone. The angle formed by the beams coming from the different sources is preferably wide open. Figure 2 shows a treatment device 10 having two sources 11, with beams that cross beneath the surface of the skin.

As shown in Figures 3 and 4, the treatment device may be provided with a system enabling it, when placed on the skin, to position an optical "head" element 13 from which the radiation exits at a given distance from the skin. As shown in Figures 3, the treatment device may include a gasket 14 of flexible material that is placed in such a manner that when the device is placed against the skin, the gasket is flattened and the optical head 13 can be brought into contact with the skin, as shown in Figure 4.

The treatment device may also include a movable optical head that is motor driven and that is provided with a system for stopping its movement when it comes into contact with the skin. It is also possible to provide a movable optical system that moves so as to come into contact with the skin under drive from a spring. Under such circumstances, it is possible to ensure that the light flux is caused to converge by an optical system configured so that the convergence is situated at a predefined distance from the optical head, e.g. a distance in the range 1 mm to 8 mm. The treatment device may include a distance- measurement system. Thus, by continuously measuring the distance D between the optical head and the surface of the skin facing it, the appliance may move the optical head towards the skin or may act on the focusing of the beams or of the light sources. The focusing is arranged to cause the light to converge as a distance £=O+d, where d preferably lies in the range 1 mm to 8 mm.

As shown in Figure 5, it is also possible to proceed by applying microlenses 20 on the skin S or close to the skin, e.g. a flexible sheet of plastics material that is molded so as to present an array of microlenses. The light is delivered, e.g. in the form of parallel rays, so as to be perpendicular to the skin. On passing through the microlenses, the light is deflected so as to converge at a predefined distance d beneath the surface of the skin, preferably in the range 1 mm to 8 mm beneath.

Targeting on the treated region The method of the invention may be implemented by selectively treating predefined zones of the region that includes sweat glands. Preferably, the targeting is associated with treatment at a predefined depth, as described above. The illumination can thus target pore zones in the skin or at least zones that present greater probability of being occupied by one or more pores, i.e. zones beneath which sweat glands are located.

As shown in Figure 6, one means may consist in applying a material 30 in the form of a sheet to the region for treatment, the sheet having optical properties, e.g. opaqueness, that change as a function of the presence of water or of other ingredients produced by the skin and associated with perspiration. Thus, a sheet of paper or of polyethylene may, under the effect of perspiration and of water or sebum, become locally transparent in zones 31 that are situated over pores P in the skin. Thereafter, by illuminating the entire region covered by the sheet, only those locations that are situated under the zones 31 that have been made transparent actually receive the light flux. Targeted treatment to a predefined depth and/or to predefined zones of the surface of the skin, in particular pore zones, is advantageously performed using mean energies that exceed 0.5 J/cm² for one application.

The treatment at a predefined depth and/or on predefined zones, in particular pore zones, may be performed with light pulses, and preferably with pulses of power greater than 1000 W, e.g. presenting 10 millijoules (mJ) per pulse.

Control, comfort, and/or safety systems

Since the energy levels used may be high, the treatment device of the invention may be provided with control, comfort, and/or safety systems.

In particular, the device may include a filter for reducing possible UV irradiation, for example.

The device may also include a heat detector or a gas detector, e.g. IR detectors, thermocouples, or CO₂ detectors, capable of issuing a warning, or of limiting or blocking irradiation. The device may include a cooling system such as a fan or a Peltier effect system, for cooling the liquid source (s) .

The device may include servo-control associating the illumination with information such as temperature for example. In particular, the system may continuously scan IR radiation over a zone that is close to the treatment zone, but that is offset therefrom. The offset may be greater than 5 mm for example, e.g. lying in the range 5 mm to 15 mm, e.g. being about 10 mm, thus making it possible to asses the temperature of the skin where it is not influenced by the irradiation. If the IR radiation, converted into degrees, exceeds a limit (e.g. 45°C), the system may warn the user of a risk of overheating. If the radiation exceeds a second limit (e.g. 55°C), the system may electronically prevent the irradiation source from operating. The device may include a casing enabling optical leakage to be limited, e.g. having a shape that is adapted to match the curves of an armpit.

When convergence under the surface of the skin is used, it is possible to provide the device with a servo- control system that allows the light flux to reach the skin only if it is possible for convergence beneath the surface of the skin to be achieved. In other words, the system may block the radiation if the device is too far away from the skin for convergence to occur beneath the surface of the skin.

In an implementation of the invention, the triggering and/or energy of the radiation is servo- controlled to a state of the skin, e.g. the presence of moisture or of heat. Thus, the treatment device may include one or more local sensors, e.g. located at the treated region, e.g. the armpits.

Direct utilization

The invention may implement direct utilization of light that consists in illuminating the treated region, e.g. the armpits, in such a manner that it is the impact of the light on the skin that creates the effects.

This utilization is recommended for acting on the perspiration phenomenon by acting on the nerves and the triggering of sweat glands, and for reducing the risk of a sensation of irritation as can be produced by moisture, rubbing, temperature, or external actions associated with fabric or with epilation, for example.

Thus, the zone in question may be treated in the morning, for example, before or after washing. This utilization is thus preventative, with treatment taking place before any perspiration produces a phenomenon of discomfort .

Optionally, a plurality of direct utilizations may be performed in a single day. It is thus possible to perform direct utilizations after perspiration has begun to give rise to phenomena of discomfort.

Combined utilization

According to the invention, in order to increase, adjust, or add to the effect of the light, it is possible to make use of complementary compounds or of other physical effects.

The compounds that may be used together with the illumination of the region for treatment comprise for example: i) agents acting in and on the phenomena of pain and/or inflammatory phenomena, e.g. those involved with or interacting on the transport of nerve impulses, transferring nerve impulses at nerve terminations, at the nerve-muscle junction, at motor end-plates, at cholinergic synapses, at post-kerasynaptic receptors, inhibitors or agents interacting in the phenomena of transport or transfer, compounds having action that is parasympatholytic, or anticholinergic, and more particularly local anticholinergic agents, e.g. curariform agents and more particularly botulinum toxin, compounds acting on the release of acetylcholine at cholinergic synapses, compounds acting on the reception of acetylcholine by post-synaptic receptors, compounds acting on acetylcholine esterase, or compounds acting on the transport of the salts involved, in particular Ca , paracetamol, derivatives of salicylic acids, and other analgesics, non-steroid anti-inflammatories, anti-Cox 2s, and agents presenting paralyzing or myorelaxing effects, such as botox, for example; ii) biomaterials, such as for example derivatives of hyaluronic acid, derivatives of cellulose and other glucides or glucide chains, derivatives of collagen or other peptides such as polylysine, polyhistidine, biomaterials involving inorganic elements in full or in part, such as silicones, for example, biocompatible materials such as hydroxyapatate or silica; iii) volatile compounds and solvents, such as water, alcohols, ethers, ketones, alkanes, alkenes, such as isododecane, volatile silicones, fragrances, and essential oils; iv) so-called anti-perspiration, astringent, or absorbent agents, such as salts of aluminum, zirconium, tannins, or derivatives of tannic acid, absorbent particles of silica, or porous polymer particles such as those sold under the name Orgasol by the supplier Atochem, for example; v) reactive agents or compositions, i.e. agents or compositions of shape that can change under the effect of a stimulus or over time. The change is not necessarily a chemical change, and it may be a physiochemical change. This category includes:

^• temperature-sensitive agents, such as for example waxes, crystalline polymers, or thermocuring polymers;

^• light-sensitive agents, such as for example photopolymerizable monomers or photocurable polymers or oligomers;

• agents suitable for reacting with the skin or with ingredients deposited on the skin, such as, for example thiols and in particular cysteine, procysteine, lipoic acid, thioglycolic acid, amino acid chains containing one or more cysteines. These may also be agents such as docosahexaenoic acid (DHA) , or reaction agents specific to the terminations of proteins and/or developers, such as ninhydrine derivatives for example or other compounds of the indane-one class; • agents suitable for reacting together such as sol- gels, e.g. siloxanes (aminopropyltriethoxysilane, reactive silicones), monomers carrying cyanoacrylate functions, combinations of molecules carrying functions suitable for condensation; iv) agents said to be have softening, emollient, or moisturizing effects on the skin. It is also possible to place on the skin fatty substances, surface-active agents, fluid lubricants, such as silicon oils, for example, solid lubricants such as particles of boron nitride, powders such as talc, magnesia, derivatives of urea such as urea itself or hydroethylide (Hydrovance) , optionally quaternized cationic polymers, cationic surface-active agents, certain surface-active agents such as Tween 20 for example; vii) optionally fluorescent, hydrophilic, or hydrophobic dyes or pigments; viii) organic or inorganic UV filters; and ix) specific agents for the skin such as retinol, proxylane, depigmenting agents, or vitamins, e.g. vitamin C. The light treatment may also be associated with treatments that are performed regularly on the hair or on other keratinous fibers, for example depilatory treatments, relaxers such as inorganic bases, organic bases, e.g. derivatives of guanidine, oxidants such as oxygenated water, persalts.

Before or after the treatment, the skin may also be subjected to physical treatments, for example: i) thermal treatment, heating, cooling, a ventilation effect, heat exchange with a solid or liquid material; ii) light treatment by exposing the skin to some other light, e.g. UV radiation; iii) an electric current, an electrostatic or radiofrequency field, for example; and iv) mechanical effects, such as rubbing to activate the circulation or stretching, a depilatory effect, or shaving . Method of administering the agents

The compounds used together with the illumination may be deposited, sprayed, injected, or micro-injected. These compounds may be deposited in a fluid form, such as a more or less fluid or creamy emulsion, e.g. a gel .

With emulsions, it is recommended to use transparent emulsions . The compounds may be sprayed on the region for treatment. They may be deposited by means of a pad situated on the treatment device that includes the source of electromagnetic radiation.

Thus, a first passage or a first scan may be performed having the effect of applying the agent without activating the illumination, and then a second passage may be performed to illuminate the region for treatment. It is also possible to proceed in the reverse order. These sequences may be repeated. It is also possible to apply a fine strip on the skin before or after treatment. The strip may optionally be adhesive. It may be removed immediately after treatment or it may be retained. The strip may be transparent or colored, pigmented, opaque, or opalescent. It may be temperature-sensitive or light-sensitive. It may be dry or moist or suitable for moistening. Thus, an example of treatment includes the steps consisting in applying a strip under the armpit, in applying a liquid or fluid to the strip, and then in performing the illumination treatment.

Methods of use

The entire area of the region for treatment, e.g. the armpits, may be illuminated. It is also possible to illuminated only a portion. Preferably, at least 25% of the zone in which it is desired to reduce perspiration is illuminated. When light is targeted on the pores, it is possible to restrict this fraction to less than 25%, e.g. in the range 5% to 15%, e.g. about 10%.

The illumination may be continuous or pulsed. It may take place on one or more occasions. During application, the illumination may vary in power and/or wavelength and/or firing rate.

It is possible to use short applications (less than 10 s) or slow applications (more than 1 hour) . In one particular circumstance the application lasts for hours. For example a device carrying the light source is placed under the armpits or light may be taken from a source distant from the armpit and conveyed thereto.

The device should be attached or fastened in such a manner as to be held firmly. The treatment may take place at night or during a period of rest. The device may also provide a metering system for stopping irradiation after a given length of time or a given amount of energy has been delivered. Under such circumstances, the treatment lasts for about 4 hours, for example.

A treatment method may consist in performing one application per day, repeated every day or once every 48 hours or every 72 hours. Preferably, the frequency of treatment is greater than once per week. The treatment by illumination may be combined with other treatments, either to increase the antiperspirant or comfort effect, e.g. resulting from applying conventional antiperspirants, or else to supplement it, e.g. by applying a deodorant or a skin softener, or else to obtain effects that are not related, but that enable time to be saved, for example depilatory treatment.

It is also possible to apply an antibacterial agent, e.g. Trichlosan.

PROPOSED EXAMPLES

Example 1

Forty LEDs referenced C1060-35 from the supplier Marubeni and using a material of the InGaAsP/InP type were mounted on a casing. Each LED produced about 0.4 mW, giving a total of 16 mW for the source. The wavelength was about 1060 nm. A converging lens was placed close to the LEDs. Convergence occurred at a distance of 30 mm from the plane of the LEDs and 4 mm beneath the base of the device. The device was provided with an electrical power supply and placed on the skin of the armpits. The user scanned the surface of the armpits slowly over about

25 cm². The treatment lasted for about 4 minutes. The energy received per square centimeter of skin was about 200 mJ.

Example 2

Two series of 60 LEDs each, the LEDs being identical to those of Example 1, were used so as to produce 120 mW. The device was placed on an armpit and scanned thereover for 70 seconds. The energy received per square centimeter of skin was about 300 mJ.

Example 3

This example used a device differing from that of Example 1 only by the fact that use was made of 60 LEDs of the AlGaAs type of reference L8700-66-60 from the supplier Marubeni were used delivering, for a current of 1 A, about 2 W of infrared light at 870 nm. The LEDs were mounted on a movable carriage suitable for moving along an X axis. The carriage was caused to move, by way of example, by a Performax ICD motor controlled by a programmable logic array, e.g. a Cyclone III EPC 3 from the supplier Altera.

Power was applied to the LEDs by the programmable logic array. The electronics for controlling movement of the motor and powering the LEDs were contained in the casing of the device. By way of example, the carriage performed two go-and-return movements in 5 s . The LEDs were activated only during that travel time. The energy received per square centimeter of skin was about 0.8 J.

Example 4 A Femto laser of reference S-Pulse HP from the supply Amplitude Systems was used. Each pulse had a duration of about 500 fs . The pulses were delivered at a rate of 1000 Hz. Each pulse presented energy of about 0.25 mJ. The wavelength was about 1030 nm. A matching optical fiber and an optical deflector operated at 100 Hz were placed at the outlet from the laser. The optical detector was mounted on a movable handle. The skin was scanned by holding the movable handle at a distance of 1 cm from the skin. The treatment lasted for 40 seconds over the area of the armpit. The energy received per square centimeter of skin was about 0.4 J.

Example 5 A matrix of near-infrared (NIR) Uno diodes was used with a spectrum centered on a peak at 870 nm, the spectral bandwidth being 50 nm at half the maximum power level of the peak. That irradiator was placed in a plastics casing providing regular spacing between the irradiator and the skin. The casing had a circular opening of 5 cm² for irradiation. The device was controlled by a Dell® mini-PC fitted with appropriate drivers .

At maximum power, the irradiator produced about 1.7 W and, because of the divergence of the IR rays at the outlet from the irradiator, it was considered that the treated surface received about 1 W. On treating the surface of each armpit for 120 seconds, the resulting dose was about 1 J per square centimeter of skin. With that device, tests were performed on a bacterial strain (Corynebacterium xerosis) constituting a model for armpit odor and cultivated on a gelose medium at different dilutions (10⁵, 10⁴, 10³, 10² bacteria per millimeter (mL) ) . The bacteria were irradiated using the device situated at a height of 26 mm, for periods of O s (control), 4 s, 16 s, and 1 minute, and then placed in a culture oven at 35°C for 2 days. After counting the cultivatable bacteria on the medium, no difference in growth was observed between the strains that had been irradiated and the control. The treatment therefore had no bactericidal effect.

Comparative Example 6

Using the same device as in Example 5, comparative tests were performed on the state of freshness of the armpits . Firstly, every morning over a period of 15 days, one armpit was treated for 120 seconds using the device while the other was left untreated. In the afternoon, a test was performed concerning moisture and the presence of odor by rubbing a finger three times under each armpit. In the evening, the odor states of the two armpits were compared at a distance of about 10 cm from the armpits.

On average, over 15 days, on 11 occasions the armpit treated by the device was favored, and on four occasions both armpits were equivalent. Still using the same device and the same dose of radiation, the experiment was repeated treating one armpit with the device and the other armpit with a composition under the Narta trademark (Narta BioFraicheur Fraicheur Naturelle) containing aluminum chlorhydrate . The same tests were performed over 15 days, in the afternoon and the evening.

On average, with the moisture test, over 15 days, on ten occasions the armpit treated by the device was favored, on one occasion both armpits were equivalent, and on four occasions the armpit treated with the Narta trademark composition was favored. For the odor test, both treatments appeared to be equivalent: over 15 days, on average, seven occasions favored the armpit treated by the device, on one occasion both armpits were equivalent, and seven occasions favored the armpit treated by the Narta trademark composition. The invention is not limited to the examples described.

The invention applies to treating regions of the body other than the armpits, e.g. the groin, the feet, the scalp, or the palm of the hand. All of the above description applies to those regions.

The term "comprising a" should be understood as being synonymous with "comprising at least one".

Claims

1. A non-therapeutic method of reducing non-pathological perspiration of a region of the human body that includes sweat glands, the method comprising the step consisting in exposing said region to non-destructive electromagnetic radiation of artificial origin having a wavelength λ longer than 400 nm and of intensity adapted to exert an action:

^• on at least one mechanism associated with the production of sweat to give rise to a temporary and non-therapeutic reduction in the activity of the sweat glands, and/or

• on a mechanism associated with the production of odor by certain bacteria present in said region.

2. A method according to claim 1, the electromagnetic radiation having a wavelength lying in the range

550 nm to 10,000 nm, better 600 nm to 4000 nm, better still 800 nm to 1200 nm, and in particular being centered on 870 nm.

3. A method according to any preceding claim, the power of the electromagnetic radiation lying in the range 0.01 mW to 5 W, and in particular lying in the range 0.5 ml to 3 i.

4. A method according to any preceding claim, the received energy lying in the range 0.0001 J/cm² to 50 J/cm² per 24 h, better in the range 0.1 J/cm² to 1 J/cm², in particular in the range 0.5 J/cm² to

2 J/cm² for irradiation lying in the range 60 s to 180 s.

5. A method according to any preceding claim, said region being subjected to scanning of said electromagnetic radiation .

6. A method according to any preceding claim, wherein the electromagnetic radiation is caused to converge under the surface of the skin, at a depth lying in a range

1 mm to 8 mm, better 2 mm to 6 mm, better still around 4 mm.

7. A method according to any preceding claim, wherein the radiation is targeted on the pores.

8. A method according to any preceding claim, wherein the region comprises the armpits, the groin, the feet, or the palm of the hand.

9. A method according to any preceding claim, the frequency of the treatment being greater than or equal to once per week.

10. A method according to any preceding claim, the exposure to the radiation taking place through a material having optical properties that change locally in the presence of water or of sebum.

11. A method according to any one of claims 1 to 10, wherein the radiation is emitted from a device in contact with the skin.

12. A method according to any one of claims 1 to 11, wherein the radiation is emitted from a device worn by the user, in particular secured to a garment and/or acting through a garment.

13. A kit for reducing perspiration of a region of the human body that includes sweat glands, the kit comprising: • a device including a source of electromagnetic radiation at a wavelength and of intensity that are adapted to exert action on at least one mechanism associated with the production of sweat in order to give rise to a temporary reduction in the activity of the sweat glands, and/or in the activity of bacteria present in said region; and • a pharmaceutical or cosmetic composition for use together with the treatment of the skin by the device, the composition having action on at least one mechanism associated with perspiration.

14. A kit according to the preceding claim, the composition including at least one agent having action on pain and/or inflammatory phenomena, in particular selected from the agents involved or interacting with the transport of nerve impulses.

15. A kit according to claim 13 or claim 14, the composition including at least one compound selected from anti-perspiration, astringent, and absorbent agents .