Patent Publication Number: US-2021177121-A1

Title: Device for preparing a cosmetic composition and associated process

Description:
The present invention relates to a device for preparing a cosmetic composition, the device comprising:
         a structure defining a housing receiving removably at least one capsule, the or at least one of the capsules containing at least one constituent of the cosmetic composition,   an outlet nozzle opening at one end of the housing, suitable for being fluidically connected to an opening of a receptacle or to a preform intended to form the receptacle, and   a piston movable in translation in relation to the structure in the housing, the piston comprising at least one piston head arranged in the housing, the piston being suitable for perforating the or each capsule on either side, and conveying contents of each capsule to the outlet nozzle.       

     The invention also relates to a process for preparing such a cosmetic composition. 
     The cosmetic composition prepared by means of the device particularly comprises a cosmetic body surface care, coloring or makeup product. 
     More generally, a cosmetic composition comprises one or a plurality of cosmetic products, as defined in EC Regulation No. 1223/2009 of the European Parliament and the Council of Nov. 30, 2009, relating to cosmetic products. 
     The cosmetic compositions are generally commercially available prepared in advance, and packaged in customized individual containers well suited to store distribution. 
     This type of packaging enables a satisfactory shelf-life and easy handling of the cosmetic composition. Furthermore, it provides the consumer with a guarantee that the packaging contents match the claimed composition, and that they are in compliance with applicable standards. 
     However, this type of product is not ideal for all clients. Indeed, it does not allow customization of the quantity or precise contents of the cosmetic composition beyond predetermined options. Furthermore, it is not as well-suited to small-scale distribution, for example for retail outlets, that do not always use the section layouts common in stores and superstores. 
     Devices for filling a container with a cosmetic product extracted from a capsule are known in the prior art, for example in the document FR 3007014. However, these devices do not allow customization of the composition. Furthermore, they do not guarantee that the packaged composition has not been exposed to external contaminants or has not received an additional compound not included in the desired composition. These situations may result in risks of a reduction in product quality, or even health risks. 
     There is thus a need for a means of preparing and dispensing cosmetics enabling greater customization and being more suitable for retail outlets, while retaining the option of guaranteeing the type and quality of the compositions dispensed. 
     One aim of the invention is thus that of providing a method for dispensing cosmetics prepared in-situ in a customized manner, and complying with all preexisting quality and traceability requirements. 
     For this purpose, the invention relates to a device of the type cited above, characterized in that the head or at least one of the heads of the piston is suitable for forming a cap of the receptacle connected to the outlet nozzle. 
     Such a device makes it possible to protect the cosmetic composition from any external contamination during preparation, and makes it possible to guarantee the integrity and conformity of the composition. 
     According to particular embodiments, the device according to the invention has one or several of the following characteristics, taken independently or in any technically feasible combination:
         a plurality of piston heads arranged in the housing separated from one another along the longitudinal axis, each head, apart from a first head positioned furthest from the end, defining a conduit opening onto two opposite faces of the head along the longitudinal axis;   each head, apart from the first head, is suitable for being fastened to a preceding head, the heads engaging to form the cap;   each conduit receives the preceding head, in a snap-locking manner, so as to seal the conduit.       

     These alternative embodiments make it possible to use a plurality of capsules having different sizes to one another, so as to adapt to the nature of the contents thereof.
         the cap is suitable for receiving a member for dispensing the cosmetic composition contained in the receptacle.       

     This alternative embodiment makes it possible to increase the dispensing possibilities of the cosmetic composition after preparation.
         The cap is suitable for being perforated prior to a first use of the cosmetic composition contained in the receptacle.       

     This alternative embodiment makes it possible to guarantee the integrity and conformity of the cosmetic composition from the preparation to the first use, preventing any contamination.
         The piston head has an outer diameter substantially equal an inner diameter of at least one capsule.   The piston heads are separable from the rod when the receptacle is detached from the outlet nozzle.       

     The invention also relates to a process for preparing a cosmetic composition, comprising the following steps:
         providing a device as defined above, and at least one capsule containing at least one constituent of the cosmetic composition arranged in the housing;   positioning of a receptacle or a preform, connected to the outlet nozzle;   movement of the or each piston head in the housing toward the end, perforation of each capsule on either side of the capsule and conveyance of the contents of each capsule toward the end;   extrusion of the contents of each capsule into the receptacle or against the preform, through the outlet nozzle, and obtaining the cosmetic composition, the receptacle defining an opening at the nozzle; and   movement of at least one of the piston heads through the opening of the receptacle, so as to form a cap for the receptacle.       

     According to particular embodiments, the process according to the invention has one or several of the following characteristics, taken independently or in any technically feasible combination:
         the device comprises a plurality of piston heads, the step of moving the piston comprising at least one substep of fastening one of the heads to another of the heads, the heads fastened to one another forming the cap;   the fastening substep comprises receiving one of the fastened heads in a conduit defined by the other fastened head, so as to seal the conduit.       

     This alternative embodiment makes it possible to use capsules having different sizes and internal volumes from one capsule to another.
         During the piston movement and extrusion steps, the piston, a side wall of each capsule, the outlet nozzle and the receptacle or the preform engage to form a circulation channel fluidically isolated from the outside.       

     This alternative embodiment makes it possible to guarantee that the composition is not contaminated during preparation by an undesired compound or by contact with ambient air. 
    
    
     
       Further features and advantages of the invention will emerge after reading the following description given solely as an example with reference to the appended drawings in which: 
         FIGS. 1 to 4  are longitudinal sectional views of a device according to the invention during successive steps of a process for preparing a cosmetic composition; 
         FIGS. 5 and 6  are perspective views of two capsules according to the invention; 
         FIGS. 7 and 8  show a device according to a further embodiment of the invention. 
     
    
    
     A device  10  for preparing a cosmetic composition  12  is represented in  FIGS. 1 to 4 . The device  10  is suitable for preparing the cosmetic composition  12 , by conveying toward the receptacle  14  and mixing a plurality of constituents of the cosmetic composition  12  contained in at least one capsule  16 , and advantageously in a plurality of capsules  16 . 
     The cosmetic composition  12  particularly comprises a cosmetic body surface makeup, care and/or coloring product. The composition  12  is prepared from a plurality of predetermined constituents, in predetermined precise proportions. 
     The constituents of the cosmetic composition comprise for example one or a plurality of liquids, of varied viscosities, aqueous or organic in nature. The constituents also comprise for example one or a plurality of solids such as powders, particles and/or fibers. Finally, the constituents comprise for example gels, emulsions, creams, foams, or others. 
     According to a first embodiment represented in the figures, the device  10  receives a plurality of capsules  16 . The capsules  16  are represented in  FIGS. 5 and 6 . Each capsule  16  contains at least one of the constituents of the cosmetic composition  12 . 
     Each capsule  16  comprises a substantially cylindrical side wall  18 , defining a substantially inner conduit  20  and two seals  22  closing the inner conduit  20  at two opposite ends. 
     The term “cylindrical” denotes that the side wall  18  and the inner conduit  20  each have an outer surface in the shape of a cylinder portion, a cylinder being understood to be the geometric shape formed by a generatrix passing through a closed directrix curve inscribed in an orthogonal plane to the generatrix. 
     According to a first alternative embodiment, the directrix curve is a circle, and the side wall  18  is thus in the shape of a cylinder portion of circular transverse cross-section. 
     According to further alternative embodiments, the directrix curve is a square, a rectangle, an ellipse, a rhombus, or other shape. 
     The above definition is applied in the same way hereinafter to any cylindrical object. 
     The side wall  18  and the inner conduit  20  each have a central axis, which passes through an isobarycenter of the respective directrix curve. The central axes of the side wall  18  and of the inner conduit  20  are particularly coincident. 
     The side wall  18  is in the form of a solid cylindrical sleeve having a substantially constant thickness on the periphery thereof, and a variable length from one capsule  16  to another. The side wall  18  is for example made of plastic material, and particularly of material transparent to near infrared radiation, such as for example methyl polymethacrylate. Alternatively, the side wall  18  is made of glass. 
     The plurality of capsules  16  particularly comprises at least one first capsule  16 , represented in  FIG. 5 , and at least one second capsule  16 , represented in  FIG. 6 . 
     The side wall  18  of each first capsule  16  has the same first outer diameter d 1  and the same first inner diameter d′ 1 . The side wall  18  of each second capsule  16  has the same second outer diameter d 2 , greater than the first outer diameter d 1 , and the same second inner diameter d′ 2 , greater than the first inner diameter d′ 1 . 
     In the example shown in the figures, the side wall  18  and the inner conduit  20  are cylindrical with a circular cross-section. In cases where the cross-section of the cylinder is not a circle, the inner d′ 1 , d′ 2  and outer diameters d 1 , d 2  should be considered as transversal dimensions of the capsules  16 , such as for example the side of a square cross-section, or the major axis of an elliptical cross-section. 
     Each first capsule  16  further comprises fins  24  protruding laterally from the side wall  18 , ends  26  of the fins  24  being inscribed in a circle of diameter equal to the second outer diameter d 2 . The fins  24  are for example of a single piece with the side wall  18 . 
     Each first capsule  16  advantageously comprises at least three fins  24 , which helps ensure effective centering of the capsule  16  when it is placed in the device  10 . 
     The seals  22  have a thin disk shape and have a diameter substantially equal to the outer diameter d 1 , d 2  of the side wall  18 . The seals  22  are attached to a transversal surface of the side wall  18 , for example by heat-sealing. 
     The seals  22  are made of a stretchable material fragile enough to tear when the seals  22  are stretched beyond a rupture threshold. The seals  22  are for example made of rubber, particularly based on a butadiene-acrylonitrile copolymer (referred to as nitrile rubber), or based on polychloroprene, or based on a latex. 
     The material forming the seals  22  are advantageously recyclable, particularly by pyrolysis or by grinding and recasting. 
     Alternatively, the seals  22  are made of a fragile material, the presence whereof in the cosmetic composition causes no discomfort, such as for example from sugar, gelatin, wax, or others. 
     The inner conduit  20  receives a content of the capsule  16 , comprising at least one of the constituents of the cosmetic composition  12 . 
     Each capsule  16  has a specific length, measured between the two ends of the inner conduit  20 , and independent of the inner diameter of the capsule  16 . The length is determined according to the volume sought for the inner conduit  20 , which is dependent on the nature of the contents of the cosmetic composition  12 . 
     Advantageously, the side wall  18  of each capsule  16  has one or a plurality of specific colors, suitable for quickly identifying the contents of the capsule  16  even once the capsule has been placed in the device  10 . 
     Alternatively (not shown), the device  10  receives a single capsule  16  containing all the constituents of the cosmetic composition. 
     The device  10  comprises a structure  28  defining a housing  30  for receiving the capsules  16 , extending along a longitudinal axis X-X′. The device  10  also comprises an outlet nozzle  32  opening at a first end  34  of the housing  30 , and a piston  36  mounted at a second end  38  of the housing  30 . 
     The device  10  is particularly positioned vertically, that is to say that the longitudinal axis X-X′ extends parallel with gravity, with the outlet nozzle  32  oriented upward, that is to say opening opposite the direction of gravity. 
     The structure  28  comprises for example a substantially cylindrical casing  40  which defines the housing  30 , the outlet nozzle  32  being positioned through the casing  40  and the piston  36  being slidably mounted through the casing  40 . 
     The casing  40  advantageously has openings for accessing the capsules  16 . Alternatively, the casing  40  is made of material transparent to near infrared. 
     Alternatively (not shown), the structure  28  is an open structure comprising a plurality of metal bars extending substantially parallel with the longitudinal axis X-X′, defining therebetween the housing  30 . The bars are assembled with two end plates, forming the ends of the housing  30 , one of the plates comprising the outlet nozzle  32  and the other plate bearing the piston  36 . The bars are arranged to serve as lateral support for the ends  26  of the fins  24  of the first capsules  16  and for the side wall  18  of the second capsules  16 . 
     Advantageously, each bar comprises a groove extending facing the housing  30 , the grooves being suitable for receiving the ends  26  of the fins  24  of the first capsules  16 , so as to prevent the rotation of the first capsules  16  about the longitudinal axis X-X′. 
     A portion of the structure  28  is movable and/or removable so as to enable the positioning of the capsules  16  in the housing  30 . 
     The housing  30  is a substantially cylindrical internal volume, having a diameter substantially equal to the second outer diameter d 2  of the capsules  16 . The housing is suitable for receiving the capsules  16  removably, pressing radially on an internal surface of the housing  30 . 
     The definitions of the terms “cylindrical”, “axis” and “diameter” given above also apply to the housing  30  and to the piston  36 . In particular, the cross-sections of the capsules  16 , the housing  30  and the piston  36  are similar. 
     The capsules  16  received in the housing  30  are aligned along the longitudinal axis X-X′, in a coaxial manner. The term coaxial denotes that each of the capsules  16  is arranged with an axis of the inner conduit  20  of the capsule  16  aligned on the longitudinal axis X-X′. 
     The capsules  16  are arranged in contact with one another, the second capsules  16  being arranged closer to the outlet nozzle  32  situated at the first end  34 , and the first capsules  16  being arranged closer to the piston  36  situated at the second end  38 . 
     The side walls  18  of the first capsules  16  are in contact against one another along a parallel direction with the longitudinal axis X-X′, so as to form a first circulation conduit  42  having a diameter equal to the first inner diameter d′ 1 . 
     Similarly, the side walls  18  of the second capsules  16  press against one another along a parallel direction with the longitudinal axis X-X′, so as to form a second circulation conduit  44  having a diameter equal to the second inner diameter d′ 2 . 
     Advantageously, the device  10  also comprises a block  46 , slidably mounted in the housing  30 , suitable for pressing against the capsule  16  closest to the second end  38  and for fastening capsules  16  pressing against the first end  34  of the housing  30 . The block  46  includes a central opening  48  enabling the passage of the piston  36  and access to the inner conduit  20  of the capsules  16 . 
     The block  46  presses on a capsule  16  situated at one end of the stack of capsules  16  to keep the capsules  16  in contact with one another. 
     The outlet nozzle  32  comprises an opening  50  in the structure  28  opening to the outside of the structure  28  on one side and into the housing  30  on the other, as well as fastening means  52  of the receptacle  14  or of a preform  54 . 
     The opening  50  is particularly a circular opening centered on the longitudinal axis X-X′. The fastening means  52  comprise for example a thread extending onto an internal surface of the opening  50 , suitable for engaging with the thread of the receptacle  14  or of the preform  54 . 
     Alternatively, the fastening means  52  comprise a clip, bayonet, pin, or other, system. 
     The piston  36  is mounted on the structure  28 , movable in translation relative to the structure  28  along the longitudinal axis X-X′ in the housing  30 , toward the first end  34 . 
     The piston  36  is also movable through the capsules  16 , and suitable for successively stretching the seals  22  of each of the capsules  16  to the rupture threshold thereof and conveying the contents of the capsule  16  toward the outlet nozzle  32 . 
     The piston  36  comprises a rod  56  extending along the longitudinal axis X-X′, as well at least one piston head arranged in the housing  30 , suitable for being set in motion by the rod  56 . 
     The piston  36  particularly comprises as many heads, having different outer diameters, as the number of different inner diameters among the capsules  16 . The heads are arranged in the housing  30  at a distance from one another along the longitudinal axis X-X′, according to an increasing order of diameter toward the first end  34  of the housing  30 . 
     Each head  58 ,  60  is arranged upstream from the capsule  16  having an inner diameter substantially equal to the outer diameter of the head furthest from the outlet nozzle  32 . 
     In the example shown in  FIGS. 1 to 4 , the piston  36  comprises a first head  58  and a second head  60 , having two different outer diameters, substantially equal respectively to the first inner diameter d′ 1  and to the second inner diameter d′ 2  of the capsules  16 . 
     The first head  58  is arranged in contact with the first capsule  16  furthest from the outlet nozzle  32 , and the second head  60  is arranged in contact with the second capsule  16  furthest from the outlet nozzle  32 . 
     Each head  58 ,  60  is arranged to be assembled successively on the rod  56  during the movement of the piston  36  through the housing  30 . 
     In the example shown in the figures, the first head  58  is arranged to be assembled on the rod  56  before passing the piston  36  through the first capsules  16 , and the second head  60  is arranged to be assembled on the rod  56  before passing the piston  36  through the second capsules  16 . 
     Each head, with the exception of the head  58  having the smallest outer diameter, defines a through conduit  62 , opening onto two opposite faces of the head along the longitudinal axis X-X′. 
     Advantageously, each conduit  62  is suitable for receiving in a complementary manner the preceding head, particularly in a snap-locking manner. The head received is suitable for sealing the conduit  62  tightly, and preventing the flow of the contents of the capsules  16  through the conduit  62 . 
     In the example shown in the figures, the second head  60  defines the conduit  62 , which has an inner diameter substantially equal to the outer diameter of the first head  58 . 
     The conduit  62  has a rib  64  extending inside the conduit  62 , about an inlet of the conduit  62 . The rib  64  reduces the diameter of the conduit at the level of  62  the inlet, so as to fasten the first head  58  received in the conduit  62  by snap-locking, as shown in  FIGS. 3 and 4 . 
     At least one of the heads of the piston  36  is suitable for forming a cap  66  of the receptacle  14  connected to the outlet nozzle  32 . In particular, all the heads of the piston  36  are suitable for engaging to form the cap  66 , as shown in  FIG. 4 . 
     The cap  66  is arranged across an inlet of the receptacle  14 , after the flow of the cosmetic composition  12  into the receptacle  14 . The piston heads  36  are separable from the rod  56  when the receptacle  14  is detached from the outlet nozzle  32  for dispensing the cosmetic composition  12 . 
     The cap  66  is particularly suitable for being perforated after the detachment of the receptacle  14  from the outlet nozzle  32 , prior to a first use of the cosmetic composition  12  contained in the receptacle  14 . 
     Advantageously, the cap  66  is suitable for receiving a member for dispensing the cosmetic composition  12 , particularly during the perforation of the cap  66 . The dispensing member is for example a pump, a dispensing bead, a makeup brush or application brush, a nozzle, a cap, a hinged lid, or other member. 
     Alternatively, the cap  66  is a rear cap of the receptacle  14 , which is intended to be opened on the opposite side of the dispensing cap  66 . This case corresponds for example to cosmetic compositions  12  presented in “stick” form, such as for example a lipstick. 
     According to a first embodiment, shown in  FIGS. 1 to 4 , the device  10  comprises a preform  54  received by the outlet nozzle  32 , as well as a mold  68  for forming the receptacle  14 . 
     The preform  54  is comprises a part  71  made of plastic material, suitable for being heated then deformed irreversibly to form the receptacle  14  receiving the cosmetic composition  12 , as well as a retaining ring  73  surrounding the part  71 . 
     The part  71  is particularly suitable for being deformed by the contents of the capsules  16  flowing through the outlet nozzle  32 . 
     The part  71  is particularly rigid at ambient temperature and suitable for softening above a softening temperature, so as to be deformed freely during the flow of the contents from the capsules  16 . 
     Alternatively, the part  71  is suitable for being deformed at ambient temperature, particularly in an elastic, that is to say substantially reversible, manner, during the conveyance of the contents from the capsules  16 . The part  71  is for example made of rubber. 
     The preform  54  has an inner surface  72  of the part  71 , facing the housing  30 , and an outer surface  74 , facing the outside and/or the mold  68 . The inner surface  72  is intended to be in contact with the contents of the capsules  16  during the deformation of the preform  54  and to receive the pressure causing the deformation. The outer surface  74  is intended to come into contact with the mold  68  following the deformation of the preform  54 . 
     The inner surface  72  and the outer surface  74  are non-hollow, that is to say the inner surface  72  and the outer surface  74  are flat or slightly concave. The term “slightly concave” denotes that a maximum depth of the concavity is less than half a transversal thickness of the part  71 , measured along the longitudinal axis X-X′, and advantageously less than or equal to one quarter of the transversal thickness. 
     Thus, the part  71  has a shape fully inscribed in a cylinder delimited by two planar surfaces, wherein are inscribed the lateral edges of the inner surface  72  and of the outer surface  74  respectively. 
     In a preferred embodiment shown in  FIGS. 1 to 4 , the inner surface  72  is non-concave, particularly substantially planar, and the outer surface  74  is non-convex, particularly substantially planar. The part  71  is then substantially cylindrical, and is engaged in the retaining ring  73  via a lateral surface. 
     According to one alternative embodiment, the inner surface  72  is concave, and the outer surface  74  is convex. The part  71  is for example an elongated tube having a rounded closed end and an open end engaged in the retaining ring  73 . 
     Preferably, the preform  54  is flat. It has a height, measured along the longitudinal axis X-X′ thereof, less than the diameter thereof, preferably less than 0.5 times the diameter thereof. 
     The retaining ring  73  has a lateral thread  76 , for fastening the preform  54  to the outlet nozzle  32 . The retaining ring  73  is composed of a more heat-resistant material than the part  71 , so as not to be degraded when the part  71  is heated and then deformed. 
     The retaining ring  73  has a smaller inner diameter than the outer diameter d 2  of the capsules  16 , such that the retaining ring  73 , when it is engaged in the thread  54 , blocks a translation movement of the capsules  16  along the longitudinal axis X-X′ in the housing  30 . 
     The mold  68  is a surface for forming the preform  54  to obtain the receptacle  14 , made for example of metal exhibiting good heat conduction properties. 
     The mold  68  is for example arranged to enable the removal of the receptacle  14  containing the cosmetic composition  12 , once the preform  54  has been formed, and to be put back in place for another use. 
     Alternatively, the mold  68  is single-use and is part of the receptacle  14  containing the cosmetic composition  12 . 
     According to a second embodiment shown in  FIGS. 7 and 8 , the device  10  includes a receptacle  14  fastened to the outlet nozzle  32 , and suitable for receiving the constituents of the cosmetic composition  12  flowing through the outlet nozzle  32 . 
     The receptacle  14  is for example a folded flexible bag comprising an opening, whereby the retaining ring  73  is fastened tightly for the fastening thereof to the outlet nozzle  32 . The bag is made of a flexible and impervious material. 
     Advantageously, the receptacle  14  contains no air when it is positioned on the outlet nozzle  32 , making it possible to prevent any contamination of the cosmetic composition  12 . Alternatively, the receptacle initially contains a neutral gas suitable for preserving the cosmetic composition  12 . 
     Advantageously, the device  10  also comprises a device  80  for heating the capsules  16 , arranged in the vicinity of the housing  30 , and a protective casing (not shown) arranged externally with respect to the heating device  80  and the housing  30 . The heating device  80  is suitable for heating each of the capsules  16  inserted in the housing  30 , independently, so as to bring the contents of the capsule  16  to a desired temperature. 
     Advantageously, the heating device  80  is also suitable for heating the mold  68  and/or the preform  54 . 
     The heating device  80  particularly comprises a plurality of sources  82  of infrared radiation, arranged to emit each of the infrared rays to one of the capsules  16 , with an individually modulated power. 
     The sources  82  are arranged to emit through the access openings to the capsules  16  of the casing  40 , or between the bars of the structure  28  depending on the case. 
     The rays have frequencies in the near infrared range, for example between 800 nm and 3 μm. 
     The rays are suitable for passing through the side wall  18  of the capsules, which is made of a material transparent to near infrared rays, and for directly heating the contents of the capsules  16  individually. 
     The power emitted by each source  82  is determined so as to bring the contents of the capsule  16  to which the source  82  emits to a predetermined desired temperature. 
     Advantageously, the device  10  further comprises a checking system  90  of the capsules  16  fitted in the housing  30 . The checking system  90  is suitable for determining whether the capsules  16  fitted in the housing  30  are suitable for contributing to the preparation of the cosmetic composition  12 , that is to say whether the capsules  16  correspond to a formula of the cosmetic composition  12  to be prepared, and/or whether each of the capsules  16  is suitable for use for preparing the cosmetic composition  12 . 
     The checking system  90  comprises for example a plurality of spectrometry cells  92 , aligned parallel with the longitudinal axis X-X′ and arranged facing the capsules  16 , intended to analyze the contents of each capsule  16  by spectrometry, using frequencies belonging to a spectrum comprising the infrared, visible, and/or near ultraviolet range. 
     Each cell  92  comprises for example at least one diode  93  suitable for emitting rays toward the capsules  16 , and at least one optical sensor  95  suitable for collecting the rays having interacted with the capsules  16  and for measuring a spectrum in a frequency band. 
     The checking system  90  further comprises a processing module  97 , particularly comprising a processor and a memory. 
     The processing module  97  is suitable for controlling each cell  92 , analyzing the measurement results of the sensors  95  and reconstructing the signature of the capsule  16 . 
     Each diode  93  is suitable for emitting rays having a frequency included in a specific band of the diode  93 . For example, each cell  92  comprises a red diode  93 , a green diode  93 , a blue diode  93 , and two diodes  93  emitting in the ultraviolet range. 
     The red, green and blue diodes  93  are suitable for emitting rays having a frequency included in the band between 600 nm and 700 nm, between 500 nm and 550 nm and between 470 nm and 490 nm, respectively. 
     The diodes  93  emitting in the ultraviolet range are suitable for emitting rays having a frequency included in the ultraviolet spectrum, that is to say for example between 100 nm and 400 nm. Advantageously, the two UV diodes emit rays wherein the frequencies are in two distinct bands of the ultraviolet spectrum. 
     Each sensor  95  is suitable for measuring a spectrum in a frequency band, that is to say a profile of the intensities of the rays collected according to the frequency thereof. 
     Each cell  92  comprises for example a measurement sensor  85  in the visible spectrum, such as a phototransistor, and a measurement sensor  95  in the ultraviolet spectrum. 
     The cell  92  is thus suitable for measuring a signature of the capsule  16  facing the cell  92 , under the control of the processing module  97 . 
     The signature of the capsule  16  is a frequency spectrum of the rays collected by the sensors  95 , and is dependent on the frequencies of rays absorbed and transmitted by the capsule  16 , that is to say by the side wall  18  and by the contents. 
     The signature of each capsule  16  is measured by emitting toward the capsule  16  rays having predetermined respective intensities and frequencies, by means of the diodes  93 , by measuring by means of the sensors  95  the spectra of the rays collected by the capsules  16 , and reconstructing the signature of the capsule  16  by means of the processing module  97 . 
     The signature of each capsule  16  is characteristic of the contents of the capsule  16  and of the side wall  18 , and makes it possible to identify the capsule  16  from a database stored in the memory, and containing the signature templates of the different capsules  16  suitable for use with the device  10 . 
     The processing module  97  is suitable for comparing the signature of each capsule  16  to templates stored in the database to determine the nature and contents of the capsules  16  placed in the housing  30 . The processing module  97  is also suitable for comparing the capsules  16  in the housing  30  to cosmetic composition formulas stored in the database and determining whether there is a match. Finally, the processing module  97  is suitable for allowing the preparation of the cosmetic composition  12  if there is a match, and for preventing it otherwise. 
     For example, the processing module  97  is connected to an activator  94  of the piston  36 , so as to allow the movement of the piston  30  only if it determines a match between the capsules  16  placed in the housing  30  and a formula stored in the memory. In particular, the processing module  97  is suitable for allowing an electrical contact between an external energy source and the actuator  94  only if the capsules  16  are determined to be suitable for contributing to the formation of the cosmetic composition  12 . 
     Advantageously, the checking system  90  is also suitable for determining the lengths of the capsules  16  arranged in the housing  30 . Indeed, if a plurality of adjacent cells  92  measure an identical signature, the processing module  97  determines that the same capsule  16  extends facing the cells  92  in question and can thus determine the length of the capsule  16  among the possible dimensions. 
     Advantageously, the checking system  90  is further suitable for determining whether one of the capsules  16  arranged in the housing  30  is unfit for use. 
     For example, the checking system  90  is suitable for measuring the presence of a marker previously placed on the side wall  18  of the capsule  16 , and enabling the activation of the piston  36  only if each of the capsules  16  has the marker. 
     The marker is for example a substance placed on the side wall  18  and having a characteristic signature in the frequency bands of the diodes and the sensors. The marker is degraded after a certain time or above a certain temperature and no longer has the same characteristic signature. The marker is for example vitamin C, or avobenzone. 
     This alternative embodiment makes it possible to check the validity of the capsules  16 , and prevent the filling and reuse thereof, since the marker is degraded after the first use of the capsule  16 . 
     According to an alternative embodiment not shown, the checking system  90  comprises at least one infrared diode  93  and at least one infrared sensor  95  arranged on an opposite side of the housing  30 , to measure the spectrum of the infrared rays traversing the capsule  16 . 
     According to an alternative embodiment not shown, the checking system  90  comprises a digital camera intended to analyze the external appearance of the capsules  16 , and particularly that of the side wall  18 , so as to determine the nature of the contents of each of the capsules  16 , by means of an image analysis performed by the processing module  97 , substituting the cells  92 . 
     According to an alternative embodiment not shown, the first capsules  16  do not include fins  24 . The device  10  includes in this case at least one independent removable insert for reducing the diameter of the housing  30 . The insert is for example in the form of a substantially cylindrical sleeve and has an outer diameter substantially equal to the second outer diameter d 2 . The insert defines a substantially cylindrical secondary housing for receiving the first capsules  16  having an inner diameter substantially equal to the first outer diameter d 1 . 
     The secondary housing opens at two opposite ends of the insert, so as to enable the circulation of the first head  28  and of the contents of the first capsules  16  toward the outlet nozzle  34 . 
     Alternatively, the insert is composed of a plurality of bars substantially parallel with one another, assembled with two end structures by the respective ends thereof, and defining the secondary housing therebetween. 
     Advantageously, the insert has a sufficient length to receive a plurality of first capsules  16  positioned end to end in the secondary housing. 
     Advantageously, the insert comprises two parts, for example connected by a hinge, so as to facilitate the positioning of the capsules  16 . 
     A process for preparing the cosmetic composition  12  using the preparation device  10  will now be described. 
     During a preliminary step, a set of capsules  16 , each containing constituents of the composition  12 , is selected according to the nature of the composition  12  sought. 
     During a first step, the capsules  16  are arranged in the housing  30 . The capsules  16  are arranged aligned along the longitudinal axial X-X′, in a coaxial manner, according to an increasing order of diameter toward the outlet nozzle  32 . 
     Piston heads corresponding to the different diameters of the capsules  16  are also inserted into the housing  30 , arranged between the groups of capsules  16  having the same inner diameter. 
     For example, the set of capsules  16  comprises first capsules  16  and second capsules  16  as described above. A first head  58  having an outer diameter equal to the first inner diameter d′ 1  is positioned upstream from the first capsules  16 , relative to the direction of travel of the piston  36 . A second head  60  having an outer diameter equal to the second inner diameter d′ 2  is positioned before the second capsules  16 , relative to the direct of travel of the piston  36 . 
     The block  46  is then moved in the housing  30 , along the longitudinal axis X-X′, until contact of the first capsules  16 , so as to position the capsules  16  pressing against one another and against the outlet nozzle  32 . 
     The side walls  18  of the first capsules  16  then form the first circulation conduit and the side walls of the second capsules  16  then form the second circulation conduit. 
     The process then comprises a step of positioning a receptacle  14  or a preform  54 , connected to the outlet nozzle  32 . The preform  54  or the receptacle  14  is fluidically connected, tightly, to the opening  50  of the outlet nozzle  32 , so as to receive the contents of capsules  16  flowing through the outlet nozzle  32 . 
     The preform  54  or the receptacle  14  is fastened by fastening means  52  to the outlet nozzle  32 . 
     The preform  54  or the receptacle  14  is particularly positioned without introducing into the housing air from outside the device  10 . 
     In the case where the receptacle  14  is positioned, it is particularly empty, such as a folded bag, or contains for example a neutral gas. 
     In the case where the preform  54  is positioned, the process comprises a step of heating the preform  54 , and optionally the mold  68 , so as to allow the deformation of the preform  54 . The preform  54  is for example heated up to a softening temperature of the part  71 . 
     The process then optionally comprises a step of heating each capsule  16  individually by means of the device for heating the capsules  16 , during which the contents of each capsule  16  are heated to a predetermined temperature, for example to fluidify same and facilitate the flow and miscibility thereof. 
     The process advantageously comprises a step of determining the property of capsules  16  of taking part in the preparation of the cosmetic composition  12 . The checking device  90  measures the signature of each of the capsules  16  and determines the nature and contents of each of the capsules  16 , as well as the presence of the non-degraded marker on the side wall  18  of the capsules  16 . 
     If the capsules  16  arranged in the housing  30  match a valid formula of the cosmetic composition  12  saved in the memory, and if the non-degraded marker is present on the capsules  16 , the checking device  90  allows the movement of the piston  36 . Otherwise, the checking device  90  signals an error. 
     The process then comprises a step of moving the piston  36  along the longitudinal axis X-X′, toward the outlet nozzle  32 , through the housing  30  and through the capsules  16 . 
     The step of moving the piston  36  comprises a first substep during which the rods  56  moves in contact with the first head  58 , followed by successive substeps of moving the piston  36  through each first capsule  16 , stretching the seals  22  of each capsule  16  to the rupture threshold thereof, and conveying the contents of the first capsules  16  toward the first end  34 . The contents of the first capsules  16  flow particularly through the conduit  62  defined by the second head  60  and are mixed in the conduit  62 . 
     The seals  22  are stretched successively about the piston  36  and line the walls of the first circulation conduit. Each seal  22  tears once the rupture threshold has been reached, so as to enable the flow of the contents from the capsules  16 . The seal  22  tears cleanly, without forming debris in the first circulation conduit, and retracts upstream from the piston  36 . 
     The step of moving the piston  36  then comprises a substep of moving the piston  36  in contact with the second head  60 , pressing the piston  36  on the second head  60 , and assembling the second head  60  on the first head  58  particularly by snap-locking. 
     The step of moving the piston  36  then comprises substeps of moving the piston  36  through each second capsule  16  and stretching each seal  22  of the second capsules  16 , and conveying the contents of the capsules  16  toward the first end  34 . 
     The process then comprises a step of extruding the contents of the capsules  16  through the opening  50  of the outlet nozzle  32 , into the receptacle  14  or against the preform  54 . 
     Advantageously, during the movement of the piston  36  and the extrusion of the contents of the capsules  16 , the piston  36 , the side walls  18  of the capsules  16 , the outlet nozzle  32  and the receptacle  14  or the preform  54  engage to form a circulation channel fluidically isolated from the outside. The side walls  18  of the capsules  16  and the head(s)  58 ,  60  are in tight contact, making it possible to prevent an entry of air from outside the device  10 , which could contaminate the cosmetic composition  12 . 
     Optionally, the process comprises a step of deforming the preform  54  so as to form the receptacle  14 . The contents of the capsules  16  flow against the inner surface  72  of the preform  54  and exert thereon a pressure which deforms the preform  54 . The preform  54  is deformed irreversibly and becomes the receptacle  14  receiving the cosmetic composition  12 , particularly in a mold  68 . 
     The process finally comprises a step of engaging at least one of the heads of the piston  36  in the receptacle  14 , so as to form a cap of the receptacle  14 . The cap is particularly snap-locked in the opening of the receptacle  14 . 
     For example, the first head  58  and the second head  60  are assembled with one another and form a cap of the receptacle  14 . 
     The process comprises steps of detaching the receptacle  14  from the outlet nozzle  32  and removing the perforated capsules  16  from the housing  30 . 
     Optionally, the process further comprises a step of perforating the cap and positioning a member for dispensing the cosmetic composition  12  on the cap. 
     Advantageously, the process comprises steps of positioning a new receptacle  14  or a new preform  54 , as well as introducing in the housing  30 , removably, a new plurality of capsules  16 , as described above, each capsule  16  containing at least constituent of a new cosmetic composition  12 . 
     The device  10  makes it possible to protect the cosmetic composition  12  from any external contamination during preparation, and makes it possible to guarantee the integrity and conformity of the composition after preparation. 
     The cap perforated prior to the first use makes it possible to guarantee the integrity of the cosmetic composition  12  until the first use. 
     The use of a plurality of capsules  16  of different diameters, associated with a plurality of corresponding piston heads  58 ,  60 , makes it possible to vary the constituents of the cosmetic composition  12  and adapt the proportions thereof simply and effectively. The positioning of a dispensing member on the cap makes it possible to vary the possibilities of use of the cosmetic composition  12 . 
     The system  90  for checking the capsules  16  makes it possible to ensure that the contents of the capsules  16  are indeed suitable for forming the cosmetic composition  12 , and that the capsules  16  arranged in the housing indeed match a valid cosmetic composition  12  formula. 
     In a variant (not shown), the side walls  18  of at least some of the capsules  16  present reliefs on the external cylindrical surface thereof, like ribs and/or grooves. These reliefs are obtained through molding and/or machining of the side walls  18 , and allows for easier identification of the capsule  18  and its content by an operator. 
     In a variant (not shown), the seals  22  are integral with the side walls  18 , and thin enough to be deformed and broken by the piston  36  moving through the housing  30 . 
     EXAMPLES 
     In a first example, the cosmetic composition  12  prepared is a shampoo. 
     The capsules  16  inserted into the housing  30  comprise, in the order from the furthest to the closest to the outlet nozzle  31 :
         a first capsule containing a first surfactant, such as for example polysorbate, of outer diameter equal to 1.2 cm and length equal to 1 cm,   two first capsules containing a second surfactant, such as for example sodium lauryl ether sulfate, of outer diameter equal to 1.2 cm and length equal to 3 cm,   two first capsules containing a polymer, for example a copolymer of acrylamide and quaternary ammonium salts, known under the name polyquaternium-7, of diameter equal to 1.2 cm and length equal to 3 cm,   four first capsules containing a third surfactant, such as cocamidopropyl betaine, of outer diameter equal to 1.2 cm and length equal to 3 cm,   a first capsule containing a fourth surfactant, such as for example cocamide monoethanolamine, of diameter equal to 1.2 cm and length equal to 1 cm,   two second capsules containing a solvent, such as for example water, of diameter equal to 3.6 cm and length equal to 3 cm.       

     The capsules  16  are traversed by the piston  36  in the order indicated and the contents thereof conveyed to a receptacle  14  attached to the outlet nozzle  31 , which prepares the cosmetic composition  12 . 
     In a second example, the cosmetic composition  12  prepared is a lip balm. 
     The capsules  16  inserted into the housing  30  comprise, in the order from the furthest to the closest to the outlet nozzle  31 :
         a first capsule containing a first solvent, such as for example 1,2-octanediol, also known under the name caprylyl glycol, of outer diameter equal to 1.2 cm and length equal to 1 cm,   a first capsule containing a first fatty substance, such as for example petroleum jelly, of outer diameter equal to 1.2 cm and length equal to 3 cm,   a first capsule containing a second solvent, for example glycerin, of diameter equal to 1.2 cm and length equal to 3 cm,   four first capsules containing a first surfactant, such as isostearyl alcohol, of outer diameter equal to 1.2 cm and length equal to 1 cm,   five first capsules containing a second fatty substance, such as for example caprylic/capric triglyceride, of diameter equal to 1.2 cm and length equal to 1 cm,   two first capsules containing a second surfactant, for example sodium stearate, of diameter equal to 1.2 cm and length equal to 3 cm,   three first capsules containing a first solvent, for example tripropylene glycol, of diameter equal to 1.2 cm and length equal to 3 cm,   a second capsule containing a silicone oil, of diameter equal to 3.6 cm and length equal to 1 cm,   a second capsule containing a second solvent, such as for example water, of diameter equal to 3.6 cm and length equal to 3 cm.       

     The capsules  16  are traversed by the piston  36  in the order indicated and the contents thereof conveyed to a receptacle  14  attached to the outlet nozzle  31 , which prepares the cosmetic composition  12 .