WO2012080969A2

WO2012080969A2 - Process for photoprotection

Info

Publication number: WO2012080969A2
Application number: PCT/IB2011/055675
Authority: WO
Inventors: Henri Samain; Didier Candau
Original assignee: L'oreal
Priority date: 2010-12-15
Filing date: 2011-12-14
Publication date: 2012-06-21
Also published as: FR2968929A1; WO2012080969A3

Abstract

The present invention relates to a process for photoprotection of a zone (P) of the skin (S), comprising protecting the said zone(P) with a film (1) more extended than the latter, the photoprotection whereof is augmented in a region (3) lying above the zone and less around that region.

Description

Process for photoprotection

The present invention relates to protection against sunlight.

The skin is made up of parts which it is desirable to photoprotect more than others, for aesthetic reasons in particular. This is the case with moles, scars, particular zones of the skin on which light can for example cause irritation, spots which may or may not be reversible, redness...

In order to photoprotect these zones more strongly than the rest of the skin, either they are photoprotected without photoprotecting the rest of the skin or they are photoprotected more than the rest of the skin which is then also photoprotected. When the photoprotection is greater on the zone to be photoprotected than that of the adjacent zones, preferably by at least 50% and more preferably by at least 100%, this is described as "augmented photoprotection".

In the case where the zones to be photoprotected more are few, the person concerned can in practice cover these zones with a photoprotective product in order to achieve this augmented photoprotection.

However, if the zones are many, which is often the case, the operation is time- consuming and risky, as some zones may be overlooked.

In addition, if the zones are small, such as for example with moles, the operation is difficult as it is necessary to use a product which remains on the zone in spite of movement and rubbing. For example, a shift of one millimetre, possibly as the result of rubbing of clothing on the skin, would affect the photoprotection of the zone.

In order to effectively photoprotect zones of small size, one possibility is to cover the whole of the exposed skin with a product providing significant photoprotection. But then the advantage of being able to beautify the skin through tanning is lost.

Another possibility is to cover a portion of the skin around the zone to be protected with a product providing significant photoprotection. But then the result is not aesthetically pleasing as the portions thus photoprotected more than necessary do not tan while the other exposed portions do tan.

The publications GB2444906, W02005027859 and DE29517506 describe patches and sticking plasters for moles, of varying sizes, allowing 99.9% protection of the said mole against UVA and UVB radiation. These solutions are only satisfactorily applicable in the rare cases when the moles are of suitable shape.

In summary, to the knowledge of the applicant, there is no known satisfactory solution making it possible to obtain augmented photoprotection with an aesthetically pleasing result, particularly if several zones and/or zones of small size need to be treated.

The purpose of the invention is to solve this problem and this is achieved by a process for photoprotection of at least one zone of the skin, comprising the stage consisting in photoprotecting the said zone with a film more extended than the latter, the photoprotection whereof is augmented in a region lying above the zone and less around that region.

In the sense of the present invention, the term "film" should be understood to mean an object, also termed a patch, of relatively small thickness, preferably flexible, of single or multilayered structure, of one or more materials, whether or not of essentially constant thickness. The film can for example exhibit a local over-thickness above the zone to be photoprotected. The film can have its final structure at the time when it is placed on the skin or adopt its final structure after having been positioned on the skin, for example by the application of a photoprotective composition onto the film. The term "film" may also be used below both to refer to the finished object also termed a patch providing the function of differentiated photoprotection, but also to any intermediate substrate, for example made of thermoplastic materials having to undergo one or more modifications or an addition or removal of material in order to achieve the desired function. The film preferably has a maximum thickness of between 1 and 200 μιη. The film is preferably not perforated.

The film can for example adhere to the skin on an area greater by 50% at least than the extent of the zone to be protected, and better greater by 100% at least than that extent. The film can for example occupy an area of at least 1 cm² and for example an area less than or equal to 10 cm².

According to other characteristics of the present invention, alone or in combination:

- the film is preferably transparent, the method comprises the stage consisting of applying locally, onto a film exhibiting homogeneous filtration properties, a photoprotective composition, in such a manner as to cover only the said zone to be photoprotected,

the method comprises the stage consisting of applying onto the film a layer for mechanical protection of the photoprotective composition, for example another film, this mechanical protection layer preferably exhibiting spatially homogeneous UVA and/or UVB filtration properties,

the method comprises the stage consisting of locally treating the film to increase its capacity for retention of the photoprotective composition, for example by locally removing a detachable film giving access to an underlying porosity of a material of the film, and applying the said composition at least where the retention is augmented, it also being possible to obtain the capacity for retention, in one modification, by exposing the film to a light stimulus in accordance with an image corresponding to the zone to be protected, in order to create locally a photoprotective composition attachment function,

- the method comprises the stage consisting of treating the film to locally modify its optical properties, in such a way as to modify its UVA and/or UVB radiation absorption properties, for example by making it locally transparent by addition of a composition that fills interstices of the film or by compression or local melting of the film, the method comprises the stage consisting of treating the film to avoid the accumulation on the film of a general photoprotection product, ending by covering the film and the adjacent skin.

the photoprotective composition is applied manually or automatically, the automatic application for example resulting from the use of a printer to print with the said composition onto a substrate of the film,

- the photoprotective composition is applied when the film is in place or prior to its being put in place,

the method can include the illumination of the film under special lighting, for example under black light, and the photoprotective composition can contain a marker fluorescent under UV to enable visualisation of the zone of augmented photoprotection when the film is put in place, the method can comprise the acquisition of an image of the zone to be protected, for example for the purpose of printing of the zone of augmented photoprotection onto the film.

A further subject of the invention, according to another of its aspects, is a kit for the implementation of the above method comprising particularly within the same packaging device:

a film for application onto the skin or a film-forming composition capable of forming a film on the skin,

a photoprotective composition for application onto the film.

The photoprotective composition has for example an SPF protection index evaluated by the SPF method greater than or equal to 30, preferably greater than 50 and a UVA protection factor such that the SPF/PPD ratio < 3.

The kit can comprise a protective layer for application onto the film once this is coated with the photoprotective composition, in particular a protective layer in the form of an adhesive protective film.

The kit can comprise on the surface of the film a detachable film for removal, for example by scraping or by means of a solvent or an energy stimulus, at the zone to be photoprotected, in order to uncover a region of film exhibiting absorption properties of a photoprotective composition augmented in comparison to the region covered by the detachable film.

The composition can contain a marker fluorescent under UV to facilitate the positioning of the film.

The photoprotective composition can be contained in an applicator, in particular operated by the user, or in a printer, which is for example used to print the film before it is put into place but which can also be adapted to print while being moved on the skin by the user.

The photoprotective composition and the film can be selected so as to react together when the photoprotective composition is applied onto the film, in order for example to form a filtering compound well attached to the film.

The invention can be better understood by reading the description that follows, non-limiting practical examples thereof, and by examining the attached drawings, wherein: figure 1 represents, diagrammatically, an example of a film according to the invention, in place on the skin,

figure 2 illustrates the stages of an example of the method according to the invention,

- figures 3A and 3B illustrate an example of modification of the film to effect the augmented photoprotection,

figure 4 illustrates the use of a mechanical protection layer on the film, figures 5A and 5B illustrate the use of a film containing a detachable protective layer,

- figure 6 represents an example of a kit for the implementation of the invention, and

figure 7 represents, diagrammatically, an example of a tool capable of assisting the user to implement the invention.

In figure 1, a region of skin S having a zone to be protected P against UVA and/or UVB radiation, for example a scar or a mole, is represented.

According to the invention, a film 1 (also termed patch) is present on the skin, for example being glued to it by means of a hypoallergenic adhesive layer 4, which is for example initially present on the film.

The film 1 comprises a first portion 2 which extends beyond the zone to be protected P and a second portion 3 which extends entirely over the zone to be protected P. The second portion 3 is more photoprotective than the first portion 2, for example by more than 50%, even perhaps more than 100%. For example, the protection factor of the second portion 3 is greater than 50%.

Portions 2 and 3 can both be transparent to wavelengths in the visible range, in order to reduce the visibility of the film.

The photoprotection conferred by the presence of the portion 3 can result from a radiation absorption phenomenon.

The first portion 2 may or may not be photoprotective. The second portion 3 can have been made more photoprotective than the first in various ways, detailed below.

In figure 1, the film 1 comprises a single second part 3 but in variant embodiments of the invention, the film 1 has several portions of augmented photoprotection, situated respectively above several zones to be protected. In one embodiment of the invention, illustrated in figure 2, the film is not or only slightly photoprotective in the state in which it is placed on the region of skin containing the zone to be protected, at stage 10, then the film is modified at stage 20 so that it becomes more photoprotective on the zone to be protected.

Several approaches are possible for thus modifying the film.

A photoprotective compound 6 can be applied onto layer 5 of the film, on the zone to be photoprotected, as illustrated in figures 3A and 3B.

As a variant, the material of the film can be transformed at the location of the zone to be protected, so that it becomes more photoprotective. In both cases, the film adheres to the skin, is sufficiently transparent for the user to be able to demarcate the photoprotection by following the contour of the zone to be protected P and the film is therefore only made once the zone for photoprotection has been demarcated and it remains located entirely or almost entirely at the zone to be protected P.

Preferably, the region of the film which is photoprotective and intended to photoprotect the zone to be protected keeps its photoprotection for several days, preferably being photostable and resistant to washing.

The film 1 is preferably created from synthetic or modified natural material(s), which are made to adhere to the skin, for example by means of an adhesive, which can be continuous or discontinuous, interacting with the film, or otherwise, before the positioning of the film. The film is for example obtained by extrusion, coextrusion or lamination.

The film can also be obtained by drying or reaction of a fluid and spreadable composition. For example, the film can comprise or consist of a polymer dissolved in a solvent, a latex or a reactive compound such as a reactive monomer or oligomer or polymer.

The film can further be obtained by reaction between compounds (X) and (Y).

These compounds can react together by a hydrosilylation reaction in the presence of a catalyst or by a condensation reaction or through a crosslinking reaction in the presence of a peroxide when they are put into contact with each other. The content of the document FR 2 933 614, describing the compounds and reactions usable to prepare the film, is included by reference.

The compound (X) can be selected from the polyorganosiloxanes comprising siloxane units of the formula: E H ^f S i D , ,, .

m ^' K 3 - )

)

wherein:

R represents a monovalent, linear or cyclic hydrocarbon group containing from 1 to 30 carbon atoms,

- m is equal to 1 or 2, and

R' represents:

• an unsaturated aliphatic hydrocarbon group containing from 2 to 10, preferably from 3 to 5 carbon atoms, or

• an unsaturated cyclic hydrocarbon group containing from 5 to 8 carbon atoms,

wherein in particular R' represents a vinyl group or a -R"-CH=CHR" ' group wherein R" is a divalent aliphatic hydrocarbon chain, containing from 1 to 8 carbon atoms, linked to the silicon atom and R" ' is a hydrogen atom or an alkyl radical containing from 1 to 4 carbon atoms, preferably a hydrogen atom, and

wherein more particularly R represents an alkyl radical containing from 1 to 10 carbon atoms or else a phenyl group, and preferably a methyl radical, and R' is a vinyl group.

The compound (Y) can be selected from the organosiloxanes containing at least one alkylhydrogenosiloxane unit of the following formula:

P £ 3 IB.

(II)

wherein:

R represents a monovalent, linear or cyclic hydrocarbon group, containing from 1 to 30 carbon atoms or a phenyl group, and p is equal to 1 or 2,

wherein in particular the radicals R represent a Ci-Cio alkyl group, preferably methyl, and wherein still more particularly the organosiloxanes Y contain at least two alkylhydrogenosiloxane units of the formula -(H₃C)(H)Si-0- and possibly contain -(H^C^SiO- units.

The catalyst is preferably platinum or tin-based. Catalysts based on platinum deposited on a support of silica gel or charcoal powder (carbon), platinum chloride, platinum salts and chloroplatinic acids can for example be cited. Chloroplatinic acids in hexahydrate or anhydrous form, easily dispersible in organosilicon media, are preferably used.

Platinum complexes such as those based on chloroplatinic acid hexahydrate and divinyl tetramethyldisiloxane may also be mentioned. As usable peroxides, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide and mixtures thereof may be mentioned.

To obtain maximum photoprotection in the location of the zone to be protected P, a photoprotective composition containing or consisting of a photoprotective compound can be deposited on the film directly above the zone to be protected, as illustrated in figures 3A and 3B.

The film can in itself, before deposition of the photoprotective composition, have little or no photoprotective action, but can absorb the filtering compound, for example one or more sun filters, or one or more combinations of filters, filtering or diffusing particles. The filtering compound can be deposited with a pen, a felt-tip or any other precise applicator, made for this purpose.

The film can also retain the filtering compound on its surface, without absorbing it.

The texture and material of the film and the chemistry and/or additives of the filtering compound are such that once the film and then the filtering compound are applied, the filtering compound remains incorporated in and/or on the film. In particular, the filtering compound preferably does not spread despite the presence of water, sweat, washing water, sea water or common cosmetic or dermatological products. It is preferably also resistant to rubbing, such as that caused by clothes or sheets or rubbing on sand.

The texture and material of the film, and the chemistry and/or additives of the filtering compound are also preferably such that the filtering compound remains localised, in order to avoid migration phenomena into the interior or on the surface of the film, since it is desirable that the filtering compound filters only on the zone to be protected.

Optionally, the film can filter or contain a filtering agent.

To protect the zone P, the method according to the invention can comprise the stages consisting of, as illustrated in figures 3A and 3B:

- applying the film above the zone to be protected, for example a mole, applying a filtering compound onto the portion of film situated opposite the zone. The filtering compound can be in the fluid state during the application thereof onto the film.

In one particular case, the filtering compound is retained on the surface of the film, for example because of a particular surface texture, for example granular.

The film and the filtering compound can be selected to react together on application. For example, the film has at least one nucleophilic function (amino, hydroxyl, thiol...) and the filtering compound has at least one electrophilic function (aldehyde, acid chloride...).

As an alternative, the film and the filtering compound crosslink together, with or without an external energy input, for example light, or the aid of a third compound, for example a photo -initiator or an oxidant.

The film can be absorbent, for example because of the presence of fibrous, porous material, the film containing for example a non-woven substrate, and the filtering compound can be applied at the location of the zone to be protected. The film can then be left as such or a protective layer 8, preventing the filtering compound from emerging and other filtering compounds from penetrating through the surface of the film outside the zone to be protected, can be deposited onto the film as illustrated in figure 4.

According to another embodiment of the invention, the film is transformed so that locally it loses its absorption capacity. For example, an oily compound which will crosslink is deposited outside the zone to be protected, or the film is heated to make it lose its porosity. Such transformation of the film can take place once the filtering compound has been applied onto the film above the zone to be protected or before applying the filtering compound onto the film.

The material for the film and the filtering compound or the additives used, for example the solvents, are preferably selected so as to obtain good absorption of the filtering compound, preferably selective absorption of the filtering compound, so that other components are absorbed little or not at all.

The film can be made locally absorbent by treatment of the region lying directly above the zone to be protected. Then the filtering compound is applied onto the whole of the surface of the film. Only the section of film next to the zone to be protected then preferentially absorbs the filtering compound. The method according to the invention can also include the stage consisting of preparing the film at the zone to be protected so that subsequently, when the user applies the filtering compound on the beach, for example, the film in the area of the zone to be protected fills with filtering product and thus creates augmented photoprotection. The film can be prepared for this purpose by means of heat or other energy, mechanical or otherwise, or the application of a reagent or a solvent. In particular, the solvent used can impart porosity to the film material. A combination of these operations is also possible.

In one embodiment of the invention, the filtering compound is deposited onto the portion of the film opposite the zone to be protected. Then a protective layer is applied to the whole as illustrated in figure 4 so that with or without reaction this layer immobilises the filtering compound.

The film can be made such that it allows vertical diffusion (i.e. in depth) of the filtering compound but little or none in the horizontal direction (i.e. in the plane of the film). For example, the film can contain or be made up of a network of vertically oriented tubes or fibres.

In one embodiment, as illustrated in figures 5A and 5B, the film contains cavities and the film is covered with a protective layer 9 blocking access to the cavities. The protective layer 9 is scratched at the site of the zone to be protected. Thus, when the photoprotective composition 6 is applied onto the whole of the surface of the film, the impregnation thereof is only allowed at the location of the zone to be protected.

Precise localisation of the filtering compound once the film is in place can result from precise application of the filtering compound or from adequate preparation of the film so that it preferentially absorbs the filtering compound at the zone.

In order to ensure the precision of application of the filtering compound or the preparation of the film, a pen, felt-tip or other fine applicator can be used, or an electronically assisted system, for example a system which combines image acquisition or colour identification of the zone and deposition of a product, for example the filtering compound or a compound preparing the film. In this case, a mobile print head or a controllable multi- nozzle print head can be used.

An assisted system can also be used which combines image acquisition or colour identification of the zone with physical preparation, for example by exposure of the film to the light and/or heat, or a treatment of the product deposited. For example, after capturing the image, the system illuminates the film with a UV source in order to create reactive radicals. Next the filtering compound preferentially reacts on the zone where the reactive radicals are present on the region intended to be superposed on the zone to be protected. In another example, after image capture, the system illuminates the film and the filtering compound with a UV source in order to create an insolubilising crosslinking of the filtering compound and/or of the film and/or of the filtering compound with the film.

The advantage of the assisted systems is that the operation can more easily be performed alone, in particular with zones of the skin that are difficult to access, particularly the back, buttocks, backs of legs, top of the head, neck, and behind the arms.

In another embodiment of the invention, the film is transformed at the zone to be protected in order to make it photoprotective without extemporaneous input of a filtering compound. For example, a physical or physico-chemical transformation of the material of the film is performed.

For example, a film is made containing a filtering compound in the form of small particles, for example crystals. This distribution of particles only produces a weak photoprotective effect. The portion of the film opposite the zone is subjected to a treatment which transforms these particles and locally increases photoprotection.

This treatment consists for example of exposure to energetic radiation (light, ultrasound ...) or the direct application of a hot element, which changes the particulate appearance and transforms the initial material totally or in part into a final material in which the photoprotective compound is better distributed. A liquid can also be applied, which gives a similar result to that of a solvent by locally dissolving a filtering compound. The film can also be rubbed to achieve a similar effect, through the use of particles which can release the active filtering compound when they are crushed.

A chemical transformation of the material can also be effected by applying a non-photoprotective compound or by treating it with a physical agent (light, IR, heat ...), capable of modifying the photoprotective capacities of the film. For example, compounds which are esters of benzoic acid, such as those described in WO 2006/100225, which under exposure to UV are transformed by a Fries reaction into a UVB and UVA chromophore can be used. Thus, the film can be "negatively" treated on the portion situated outside the zone to be protected in order to eliminate or lessen its filtering ability, or to make it lose its capacity to absorb or react with a filtering compound applied onto the film later.

The film can be multilayered, so that, in particular, the photoprotective compound cannot migrate towards the skin. Furthermore, the film can contain compounds for treating the skin, for example to hydrate it.

It can also advantageously display a permeation capability so as to allow air and water to pass through.

A computerised expert system can be provided, according to one embodiment of the invention, to facilitate the selection of the film suitable for the portion of skin treated. For example, the system is informed of the skin zone and from this the system then deduces the correct film to be used, that most suitable in terms of colour, strength of adhesion, elasticity, thickness, strength of the upper surface and porosity. For example, on the face and other visible zones, the computerised system favours especially fine and transparent films. For zones which are not very visible but subject to rubbing (shoulders, feet...), the system favours stronger films, even if they are more visible.

The computerised system can also be informed concerning the number, shape and area of the zones to be treated and suggest the film accordingly so as to minimise its area while ensuring adequate adhesion.

The system used to assist the user can also be configured to cut the film, if required.

The application of the film can be facilitated by the use of a magnifying optical system and/or an image transmission system, whether or not electronically assisted. For example, an optical system is used, comprising a platform to be placed on the skin, fitted with a magnifying glass or a camera maintained at a given distance from the skin. A film application tool can be introduced between the magnifying glass and the skin.

The application of the film can if necessary be facilitated by the use of a means which indicates whether or not a photoprotective composition has already been imparted to the film. For example, a photoprotective composition is used containing an agent making it possible to identify it, which is only visible under certain conditions, by fluorescence for example, or is visible owing to its appearance under ambient lighting, because of its colour or its cloudy appearance. The agent can persist over time, or disappear over time, for example naturally or through washing.

Thus, films with no photoprotective composition can be applied onto all the zones to be protected and the films subsequently treated one by one by application of the photoprotective composition onto them, without fear of forgetting to treat a film or fear of treating the same film twice.

If necessary, a UV illumination device which shows whether a portion of the film has already been treated can be used. In particular, a platform fitted with a magnifying glass or camera and two forms of illumination can be used, so as to have illumination with visible light for the treatment of the film, and UV illumination for checking the correct treatment of the film for deposition of the filtering compound thereon and to ensure correct positioning of the filtering compound above the zone to be protected.

An optical or automated system can be used to verify that the film is present, correctly positioned opposite the zone to be protected and/or to verify that the photo- protective power of the film opposite the zone is sufficient.

A system can be used which scans the skin, particularly under far UV light or a Wood's lamp, and assesses the correct location of each film by comparing the positioning and the level of filtration compared to what they were at the time of application. Such a system can thus warn when a film must be replaced or reactivated, or alert that a film will soon have to be replaced or reactivated.

Depending on the situation, the films can be changed or simply reactivated. For this, filtering compound can be reapplied above the zone to be protected. Any protective layer can be removed, and the compound then reapplied.

A new film according to the invention can also be added onto a film which is in place, and if necessary all or some of the stages of the method according to the invention can be repeated.

An automatic system can be used to effect the reactivation of the film. In particular, such a system can be used to localise the section of the film having to exhibit the augmented photoprotection and effect the reactivation on the localised zone situated above the zone to be protected. One or more marks making it possible to locate the film or films for their removal can be used. Compounds dissolving or softening the adhesive can be used for the removal of the film or films.

When the user needs to photoprotect the rest of the skin, it is desirable that once the film or films have been placed and once the general photoprotection product has been applied over all the exposed areas, an aesthetically pleasing tan is obtained.

Thus, for example it is desirable that the skin under the area of the film, outside the zone to be protected P, is neither more nor less photoprotected than the rest of the skin. Otherwise this would create regions of skin which are not aesthetically pleasing, being more or less tanned than the rest of the skin.

The film can thus accept a general filtering compound which is part of a general photoprotection product which is moreover used on the body or face.

In one alternative, the general filtering compound and the film are selected so that the general filtering compound disappears little by little or during washing, at the same rate as its disappearance when it is applied onto the skin. In this way, accumulation of the general filtering compound in the film and the surface of the film daily becoming more strongly filtering are avoided.

The filtration by the general filtering compound on the surface of the film remains at the same filtering level as that provided on the rest of the skin. Only the area opposite the zone to be protected P permanently retains its filtration power at a high level.

The film and its possible means for effecting the augmented photoprotection and the general filtering compound are preferably provided as a kit, for example within a single pack or are recommended to be used in combination. This allows easier regulation of the wear properties of the filters so as to have the best performance on absorption and desorption, in order in particular to ensure that the general filtering compound does not accumulate more in the film than in the skin.

An example of a kit 30 which contains, within the same pack 31, a container 32 containing the general photoprotection product, one or more films 1 and an applicator 33 to create an area of augmented photoprotection on the films 1 is shown by way of example in figure 6.

The augmented photoprotection may not exhibit the same balance as regards the types of UV stopped as the photoprotection provided by the general photoprotection product used to protect the rest of the body. Preferably, the augmented photoprotection protects against UVB and UVA, and even other wavelengths, and more preferably protects almost totally against UVB.

The invention can be implemented alone or with the help of another person, for example in a beauty salon.

It is intended for everyone and is well-suited to those who have difficulty in taking care of themselves, such as children, and elderly or disabled people.

In an embodiment of the invention, illustrated in figure 7, a tool 40 is used to scan the skin (for acquisition of the 2D image of the skin) containing one or more zones P requiring augmented photoprotection.

In addition this tool makes it possible to produce a film 1 whereof at least one part 3 is made photoprotective such that when the film is applied onto the skin, the part made photoprotective covers the zone to be protected.

The non-photoprotective zone 2 does not cover the zone to be protected, and serves as a foundation for better wear protection over time, according to the invention. The film is partially photoprotective and therefore does not fit the contour of the zone to be protected P. The photoprotective part of the film fits the outline of the zone to be protected.

In one particular example, the film goes beyond the zone to be protected with specific shapes. For example the width of the non-photoprotective zone is constant.

In a preferred example of the invention, the following operations are automatic:

- scanning of the skin. Typically an image acquisition tool 41, such as a CCD camera, is used. The identification of the zones can be effected automatically, using a software method for image processing and pattern recognition known in the prior art;

- production of the film. Following the scan of the skin, a printer 42 is used, which deposits a photoprotective compound following the outline of the zones to be protected. As an alternative, an apparatus can be used which, for example by heating or other physical treatment renders certain areas of the film photoprotective, in accordance with the outline of the zone.

The tool may be made such as to apply the film onto the zone of the skin to be protected, in a suitable manner such that the photoprotective portion or portions coincide with the zone or zones to be protected. To adjust the setting, it can be based on the position of the zone or zones to be protected or other characteristic points, whether natural or deposited onto the skin beforehand. It may use a guiding system and/or system for movement and for transformation of the shape of the film, for example by homothetic stretching, so as to apply the photoprotective part of the film with the best possible fit.

In a preferred embodiment of the invention, the tool incorporates all the components for performing two or three of the operations listed above. The three operations are for example accomplished according to a sequential programme.

In one embodiment of the invention, the operations are performed automatically and can be monitored by a specialist who may be present or remote.

In a preferred example, following the scan and identification of the zones to be protected, for example because of their different colour from the rest of the skin, the tool can select the film and photoprotective composition most suitable for each zone.

In one example, the tool can be moved manually across the skin and perform the above operations as it goes. For example, the tool is first moved across the whole of the skin. During this phase, it memorises the zones to be treated. Then the tool produces all the necessary films and delivers them all at once, for example in the form of one or more adhesive sheets, or one by one. Then the user applies the films onto the zones to be treated.

As a variant, the tool is first moved across the whole of the skin, memorises the zone or zones to be treated and produces the film or films without delivering them. Then the tool is again passed over the skin. The tool rescans the skin and, whether or not applying it, delivers the film corresponding to each zone to be protected which it has identified.

Some operations can be done manually, or be mechanically and/or electronically assisted. For example, the scanning can be done manually, for example using a tracing medium onto which the contours of the zones are transferred by transparency. The tracing medium is then transferred into the tool, which can determine the shape of the zones to be protected and produce the film or films.

The scan can be done in a user-assisted manner; for example, the skin is scanned with a camera or a photographic apparatus which transfers the image onto a screen. The user identifies on the screen the zone or zones to be protected, or defines the contours of the zones to be protected using a mouse.

The production of the film can be manual; for example, the user places the photoprotective compound onto the desired location by hand. The production of the film can also be electronically assisted. For example, the tool used to assist the user prints a coloured contour or relief of the zone to be treated onto the film. The user places the photoprotective compound onto the film by hand, following the contour.

The film can be applied manually; for this, the user attempts to make the photoprotective region of the film coincide as well as possible with the skin in order to well cover the zone to be protected. The application of the film can also be assisted; for example, the tool used deposits onto the film and/or onto the skin at least one indicator which allows the user then to deposit the film quickly and/or precisely onto the skin. For example, the tool forms points on the skin, for example four points, and on the film, which will allow the user, by making them coincide, to obtain a perfect fit. The points or other markers can have a different colour and/or shape in order to assist the placing of the film.

Any exact application technique can be used to apply the photoprotective composition onto the film, in particular using the techniques of ink-jet, laser, sublimation, contact or lithographic printers or photocopiers.

The film can be post -treated in order to stabilise or improve the wear properties of the photoprotective compound on or in the film; in particular, the method according to the invention can include the implementation of a crosslinking or application treatment of a protective layer on the film.

The film can have different shapes. For example, a tool is used which cuts the film according to a predefined shape. A marker, for example a dotted line, can also be made to appear on the film, enabling manual or assisted cutting of the film.

Among implementations involving scanning, a fully integrated system can be used which performs both the scan and the printing of the film with a filtering compound plus the application of the film.

In a fully integrated system modification, this performs the scan, application of the film, and then the printing of the filtering compound.

In another fully integrated system modification, the system performs the scan and the deposition of the filtering compound, then the application of a mechanical protection layer onto the film.

A system which operates in two stages can also be provided. The user places a film onto the skin then positions a device which performs two operations: the scanning and the deposition of a filtering compound onto the film above the zone to be protected. Practical Examples

Example with placing of a film then use of an applicator.

2 cm by 2 cm transparent films are produced by cutting up an adhesive film transparent to UVA and UVB. A film such as those described in the patent applications WO 2009/041122 and WO 2009/041121 can be used. A guar gum composition (Jaguar C13S, 1.5% by weight in water) is deposited onto the film. It is allowed to dry and a transparent film which can be placed onto the skin is thus obtained. An area of skin containing two moles is selected. Because of its transparency, the two moles are visible through the film.

An applicator pen delivering a water-alcohol composition (ethanol/water = 50/50) of Mexoryl SX at 15% by weight (filtering compound) is made. This composition is applied precisely, using a magnifying glass, onto the film at the location of the zone to be protected.

A transparent mechanical protection layer consisting of the same adhesive film is then applied onto the whole.

The zone to be protected is thus provided with augmented photoprotection and the skin outside the protected zone can tan normally.

Example with scanning

A device containing a camera, PC-based electronics capable of processing images, detecting zones to be protected, and controlling an ink-jet printer, a screen, a keyboard, a mouse and a sticker printer, the reservoir whereof is filled with aqueous Mexoryl SX (15%>) solution, is made.

A sheet of precut stickers is taken. An adhesive transparent film onto which a composition of guar gum (Jaguar C13S, 1.5% in water) and 0.2%> by weight of fluorescent compound SP 3632 has previously been deposited is placed on each sticker.

The device is programmed so that, starting from an acquired image of the skin, it creates a JPEG image file where the identified zones are in black and the other zones are in white. The device controls the printer to print the file image with the photoprotective composition onto one of the stickers, in the true proportions. The user removes the sticker from the sheet after printing, then, coming close to the skin, unsticks the film from the sticker.

Under black light, which causes fluorescence of the fluorescent compound on the film, except at the location covered by the photoprotective composition, the user positions the film on the skin, using the fluorescence to help match the photoprotective section with the zone.

The invention is not restricted to the examples described.

The phrase "containing one" is synonymous with "containing at least one".

Claims

1. Process for photoprotection of a zone (P) of the skin (S), comprising protecting the said zone (P) with a film (1) more extended than the latter, the photoprotection whereof is augmented in a region (3) lying above the zone and less around that region.

2. Process according to Claim 1 , comprising applying locally, onto a film exhibiting homogeneous filtration properties, a photoprotective composition (6), in such a manner as to cover the said zone (P) to be photoprotected.

3. Process according to the previous claim, the photoprotective composition

(6) being in a fluid state during the application thereof onto the film (1).

4. Process according to any one of Claims 2 and 3, comprising applying onto the film (1) a layer (8) for mechanical protection of the photoprotective composition (6).

5. Process according to any one of the previous claims, comprising locally treating the film (1) to increase its capacity for retention of the photoprotective composition and applying the said composition (6) at least where the retention is augmented.

6. Process according to any one of the previous claims, the photoprotective composition being applied manually.

7. Process according to any one of Claims 1 to 5, the photoprotective composition being applied automatically.

8. Process according to any one of the previous claims, the photoprotective composition being applied when the film is in place on the skin.

9. Process according to any one of the previous claims, comprising treating the film to locally modify its optical properties.

10. Process according to any one of the previous claims, the photoprotection in the region (3) being augmented by a radiation absorption phenomenon.

11. Process according to any one of the previous claims, the region (3) taking on the shape of the contour of the zone (P) to be protected.

12. Kit for the implementation of the process according to any one of the previous claims, comprising: a film for application onto the skin or a film-forming composition capable of forming a film on the skin,

a photoprotective composition for application onto the film.

13. Kit according to the previous claim, comprising a protective layer for application onto the film coated with photoprotective composition, in particular a protective layer in the form of a protective film.

14. Kit according to any one of Claims 12 and 13, the film comprising a detachable film (9) for removal at the zone to be photoprotected, to uncover a region of film exhibiting absorption properties of a photoprotective composition increased relative to that covered by the detachable film.

15. Kit according to any one of Claims 12 to 14, the photoprotective composition comprising a marker fluorescent under UV.

16. Kit according to any one of Claims 12 to 15, the photoprotective composition being comprised in an applicator or in a printer.

17. Kit according to any one of Claims 12 to 16, the photoprotective composition and the film being selected so as to react together when the photoprotective composition is applied onto the film.

18. Kit according to any one of Claims 12 to 17, comprising an integrated system making it possible to scan the skin and to print a film with the photoprotective composition.