FR2981833A1 - PACKAGING OF COSMETIC PRODUCT PACKAGING - Google Patents

Abstract

The invention relates to a packaging bag of a cosmetic product comprising two flexible sheets secured along their peripheral edge so as to define a peripheral sealing zone and an internal volume, each sheet forms a multilayer complex comprising a metal layer, an adhesion agent comprising a copolymer comprising at least 7% by weight of carboxylic and / or carboxylate units, the carboxylic units possibly being in acid or salt form, and a peelable polymer layer bonded to the metal layer via said membership agent. According to the invention, the bag is characterized in that it comprises compartments separated by weak welds between the two peelable layers.

Description

The present invention relates to a device for packaging a cosmetic product. More specifically, the invention relates to a packaging bag. The invention also relates to a method for producing such a bag.

"Cosmetic product" means any product as defined in Regulation (EC) No 1223/2009 of the European Parliament and of the Council of 30 November 2009 on cosmetic products. It is known in the field of devices for packaging doses or samples of cosmetic product, bags made from two flexible sheets whose peripheral edges are welded together to form a bag. This type of packaging is easy to make, inexpensive and has a small footprint especially after use of the product it contains. In order to use the product contained in the bag, the user breaks the seal, for example by tearing a breakable area of the bag or by using a pair of scissors, to create a dispensing opening. Thus documents FR2760436 and US6557731 are known, pouches with a single compartment provided for example linked to each other by their free edges. Each of these bags, however, is for single use, since after opening the entire product contained inside the bag must be used to prevent its alteration. Packaging devices comprising several compartments are also known for using the product remaining in the container several times or for making extemporaneous mixtures of products contained in different compartments. Thus known from EP1021356, a multi-chamber container formed of a stamped thermoplastic part closed by a cover sheet. The use of a stamped thermoplastic part makes the manufacture of the container more complex and expensive than a bag. In addition this type of container is not adapted to receive certain chemical compositions such as those used in the field of dyeing keratin fibers.

To make this type of packaging impermeable to light, gases and steam, the material of which the packaging is made must have at least one barrier layer, for example a metal foil. As the metal foil is not able to satisfy all the requirements of a packaging material, in practice one or both sides of the metal foil are coated with other layers, in particular plastic materials to obtain a laminated material containing multiple layers can provide packaging materials suitable for shaping. It is also known to adapt this type of material for packaging in sachet products such as compositions containing an alkalizing agent, in particular those containing ammonia, for example compositions in the field of dyeing keratin fibers. For example, document FR2879170 discloses the use of laminated material suitable for producing sachets containing hair coloring products. However, these bags are formed of only one compartment because the material used is not suitable for producing separate compartments by a weld whose sealing strength is less than that of the perimeter of the bag. Each of these bags is however disposable, because after opening the entire product contained inside the bag must be used to prevent tampering. Thus one can not use alternatively either the total volume for example for a total hair, or the partial volume of one or more compartments for example for shorter hair, or to make mixtures with other products contained in d ' other sachets. The present invention therefore aims to provide an improved device for packaging a cosmetic product to overcome the aforementioned drawbacks. For this purpose, the invention proposes a sachet for packaging a cosmetic product comprising two flexible sheets secured along their peripheral edge so as to define a peripheral sealing zone and an internal volume, each sheet forming a multilayer complex comprising a metal layer, an adhesion agent comprising a copolymer comprising at least 7% by weight of carboxylic and / or carboxylate units, the carboxylic units may be in the form of acid or salts, and a layer of peelable polymer bonded to the layer; metal via said adhesion agent. According to the invention, the bag is characterized in that it comprises compartments separated by weak welds between the two peelable layers. According to other features of the invention, the adhesion agent may be a copolymer of ethylene and acetic acid. The peelable polymer layer can be made from peelable polyethylene. The invention will be better understood on reading the following description of nonlimiting examples of implementation thereof, with reference to the accompanying drawings, in which: - Figure 1 shows schematically an example of a packaging device a cosmetic product according to the invention; FIG. 2 is a cross-sectional view of a material used to form the device of FIG. 1; FIGS. 3 and 4 show variants of the device of FIG. 1; FIG. 5 represents the steps of a method of manufacturing the device of FIG.

In the following description, the terms flexible or flexible are used to describe a material that deforms under the pressure exerted by a user typically greater than 10 g. These terms are not synonymous with the elastic term. With reference to the figures, a sachet 1 for packaging a cosmetic product P comprising two flexible walls 11, 12 secured along their peripheral edge so as to define a peripheral sealing zone 14 and an interior volume 13 receiving the cosmetic product P.

The bag 1 consists of two flexible walls 11 and 12, for example substantially rectangular. The flexible walls 11 and 12 are made of multilayer sheets. A cross-sectional view of a multilayer sheet for producing the bag 1 is shown in FIG. 2. This multilayer sheet having a laminated structure comprises at least the following layers superimposed on each other in the following order: a layer metal 4, for example aluminum film - an adhesion agent comprising a copolymer comprising at least 7% by weight of carboxylic and / or carboxylate units, the carboxylic units being in the form of acid or of salts, and - A layer of a non-metallic material forming a first outer structure 6 intended to be in contact with the product P. This outer structure 6 is for example a layer of plastic material such as peelable polyethylene. These multilayer sheets will be more precisely described in the following description. The rectangular bag 1 has a lower edge 15, two lateral edges 16 and an upper edge 17, the latter being the one through which the distribution of the product P will take place. The dimensions of the walls 11 and 12 forming the bag are, for example, between 10mm and 200mm for the width, and between 20mm and 300mm for the length. The sealing zone 14 on the peripheral edge of the walls 11 and 12 is for example obtained by hot welding, gluing or any other known means for obtaining a strong weld. By "sealing" or "strong welding" is meant a definitive weld between two layers, for example obtained by melting and mixing these two layers together, that is to say that the strong welding between two layers can not be dissociated. without the walls with these two layers being altered. On the other hand, by "adhesion joining" or "weak weld" is meant a non-definitive weld between two layers of identical material, that is to say that the weak weld between two layers can be dissociated with from a stress threshold without the walls comprising these two layers 5 are altered. A weak weld of two layers of peelable material generates a surface adhesion between these two layers while a strong welding of these two same layers causes the mixing of these layers causing them to lose their peelable character. For example, these two different welds are obtained by varying the threshold of the pressure and that of the quantity of heat brought during these welds, a weak weld being obtained by applying a pressure and a quantity of heat less than for a weld strong. By way of example, the sealing zone 14 has a width of between 3 mm and 30 mm from the edge of the bag 1. In this example the sealing zone of the upper edge 17, the lower edge 15 and the lateral edges 16 presents a width of about 5mm. The sealing zone 14 of the upper edge 17 may be located at the end of a narrowing of the walls so as to form a neck 18 defining a dispensing passage 19 defined by said flexible walls 11 and 12, and extending according to an axis XX of the interior volume 13 to the upper edge 17 sealed pouch 1. The axis XX is also the longitudinal axis of the bag 1. The bag 1 also comprises an opening means 20, for example by tearing or cutting with a pair of scissors, to release the upper end of the dispensing passage 19. The opening means is for example a precut line along the upper edge 17 passing in the sealing zone 14 on either side passage 19 and at the passage 19 in order to be able to detach the portion of the sealing zone 14 from the upper edge 17 to the end of the dispensing passage 19. The precut line can be made for example by laser, by starting only an outer layer of the multilayer material which can then easily be torn without tools.

The bag 1 may also comprise a so-called "fine" weld 22. This type of thin weld is made for example by an ultrasonic weld which brings a high pressure and a high heat on a very small surface, so that this weld is as definitive as a strong weld, but in a very localized way. A thin weld can thus have a width of less than 1 mm. This thin weld advantageously limits the alteration of the product that may be contained in the bag at the time of welding. In the example of Figure 1, a thin weld 22 is made transverse to the axis XX in the distribution passage 19, each end connecting the sealing zone 14 so as to obtain an end compartment 13a located between the edge This end compartment 13a of small volume makes it possible, for example, to take a small quantity of product to carry out a test of innocuity of the product, before completely applying all the product contained in the product. sachet 1. For this purpose two opening means 20 are positioned on either side of the thin weld. The opening means located between the upper edge 17 and the thin weld 22 opens the end compartment 13a while the other opening means 20 opens the bag 1 to deliver the product contained in the rest of the interior volume 13. According to the invention, the interior volume 13 of the sachet 1 comprises at least one weak weld 19, each end of which is connected to the sealing zone 14 so as to define on each side each weak weld of the compartments (13b, 13c, 13d, 13e) in the inner volume 13, the low weld to obtain a seal between the compartments to prevent a product contained in a first compartment migrates to a second compartment. However, when the user applies pressure on the flexible bag at a compartment, such a weak weld dissociates under the force of the pressure transmitted by the product to the weak weld, thus allowing the passage and mixing of the product. one compartment with that of the adjacent compartment. In Figure 1, the bag has three weak welds 21 transverse to the axis X-X of the bag 1, so as to define four compartments (13b, 13c, 13d, 13e). The multilayer sheets are chosen to condition a cosmetic product, the layer of nonmetallic material 6 forms a first external structure 6 able to be brought into contact with the product, and the metal layer 4 may also be covered, on a side opposite to the one at which the first outer structure 6 is retained, a second outer structure 2. This second outer structure 2 can be made from one or more layers joined together paper, cardboard, and or thermoplastic materials such as vinyl plastics for example based on polyvinyl chloride (PVC), polyester, polyolefinic plastics, or polyamides. Examples of plastics based on polyvinyl chloride (PVC) are vinyl plastics containing vinyl chloride units in their structure, such as copolymers of vinyl chloride with vinyl esters of aliphatic acids, copolymers of vinyl chloride with esters of acrylic or methacrylic acid or with acrylonitrile, copolymers of vinyl chloride with diene bonds and unsaturated dicarboxylic acids or their anhydrides, copolymers of vinyl chloride and vinylidene with unsaturated aldehydes, ketones, etc. or polymers and copolymers of vinylidene chloride with vinyl chloride or other polymerizable compounds. Vinyl-based thermoplastics can also be softened in a manner known per se by means of primary or secondary plasticizers. The PVC sheets can also be monoaxially (oPVC) or biaxially stretched, depending on the case. Examples of polyesters-based plastics are polyalkylene terephthalates or polyalkylene isophthalates having alkyl groups or radicals containing from 2 to 10 carbon atoms or alkyl groups containing from 2 to 10 C atoms which are interrupted at least by an O-, such as for example polyethylene terephthalate (PET films), polypropylene terephthalate, polybutylene terephthalate (polytetramethylene terephthalate), polydecamethylene terephthalate, poly-1,4-cyclohexyldimethylol terephthalate or polyethylene-2 , 6-naphthalenedicarboxylate or copolymers of polyalkylene terephthalate and polyalkylene isophthalate, the proportion of isophthalate being for example from 1 to 10 mol%, copolymers and terpolymers, as well as block polymers and grafted variants of the aforementioned substances. Other suitable polyesters, such as polyethylene naphthalate, are known in the technical world under the abbreviation PEN. Other polyesters are copolymers of terephthalic acid and another polycarboxylic acid with at least one glycol. Copolyesters of terephthalic acid, ethylene glycol and an additional glycol are suitable. The glycol-modified polyesters which are known in the technical world under the name PETG are preferred. Suitable polyesters are polyalkylene terephthalates having alkyl groups or radicals having 2 to 10 carbon atoms and polyalkylene terephthalates having alkyl groups or radicals containing 2 to 10 carbon atoms which are interrupted by 1 or 2 -0- . Other preferred polyesters are polyalkylene terephthalates having alkyl groups or radicals containing 2 to 4 carbon atoms, and polyethylene terephthalates are most preferred. Among these polyethylene terephthalates are also A-PET, PETP and the cited PETG or G-PET. Examples of polyolefinic materials are polyethylenes (PE), for example high density polyethylene (HDPE, density greater than 0.944 g / cm 3), medium density polyethylene (MDPE, density of 0.926 to 0.940 g / cm 3), linear polyethylene of medium density (LMDPE, density 0.926 to 0.940 g / cm3), low density polyethylene (LDPE, density 0.910 to 0.925 g / cm3) and linear low density polyethylene (LLDPE, density 0.916 to 0.925 g / cm3), for example in the form of unoriented sheets (PE foil) or oriented monoaxially or biaxially (oPE foil), polypropylenes (PP), such as axially or biaxially oriented polypropylene (PPO foil) or cast polypropylene (PPP foil), polypropylene amorphous or crystalline or their mixtures or atactic or isotactic polypropylene or their mixtures, poly-1-butene, poly-3-methylbutene, poly-4-methylpentene and their copolymers, then polyethylene with acetate of vinyl, vinyl alcohol, acrylic acid, such as, for example, ionomeric resins, such as ethylene copolymers of acrylic acid, methacrylic acid, acrylic esters, tetrafluoroethylene or polypropylene, furthermore random copolymers, block copolymers or olefin-elastomer polymer blends. The polyolefinic materials may also include cycloolefins as a monomer of a homopolymer or copolymers. High density polyethylenes and polypropylenes as well as ionomers, for example known under the trade name Surlyn, are preferred. Examples of polyamides (PA) for plastic sheets are constituted for example by polyamide 6, homopolymer of cca pro lactam e (polycaprolactam); polyamide 11, polyamide 12, 20-laurine-lactam homopolymer (polylaurinelactam); polyamide 6,6, homopolycondensate of hexamethylenediamine and adipic acid (polyhexamethyleneadipamide); polyamide 6, 10, homopolycondensate of hexamethylenediamine and of sebacic acid (polyhexamethylenesbacamide); polyamide 6,12, homopolycondensate of hexamethylenediamide and dodecanoic acid diacid (polyhexamethylenedodecanamide) or polyamide 6-3-T, homopolycondensate of trimethylhexamethylenediamide and terephthalic acid (polytrimethylhexamethyleneterephthalamide), and mixtures thereof. The polyamide sheets are drawn monoaxially or biaxially (oPA). The second outer structure 2 is preferably composed of polyalkylene terephthalate, for example polyethylene terephthalate, so as to improve the impact resistance of the material 1 finally produced, in particular to improve the impact resistance that could be experienced from the outer periphery of the packaging device at least partly delimited by a flexible sheet forming a first wall made from this material 1.

The second outer structure 2 generally has a thickness of between 12 μm and 25 μm. Where appropriate, this second outer structure 2 is contiguous to the metal layer 4 by means of a layer 3 of a second adhesion agent made from suitable rolling adhesives that may contain solvents or be free of solvents and also contain water. Examples of laminating adhesives are acrylate adhesives containing solvents, solvent-free or aqueous, or polyurethane-adhesive systems. But it is also possible to use glues which harden under the effect of electromagnetic radiation (for example under UV radiation or electron beams). This layer 3 can also be produced from diisocyanate or aliphatic polyesters, or from suitable lacquers, for example acrylate lacquers, epoxy resins, melanin resins or urea resins. , polyurethanes, cellulose nitrate, polyesters and mixtures thereof. Lacquers for example may be solvent-based or water-based or be one, two or more component systems. The lacquers are for example hardenable by drying, hot, chemically and / or by radiation (UV, electron beams, IR). Preferably, the layer 3 is made of polyurethane. It has, for example, a thickness of between 2 and 5 μm, preferably of the order of 4 μm. In variant not shown, the second outer structure 2 is a varnish suitable for being directly attached to the metal layer 4. The metal sheet 4 according to the invention may be made of iron, steel, nickel, copper, tin, bronze, brass, aluminum, etc. Advantageously, the metal foil 4 is made of aluminum having a degree of purity of 99.95% to 97% (% by weight), the remainder being unavoidable impurities or alloying elements. Examples of alloys are those having as their main component aluminum and as Fe alloy elements; Yes ; Mg; Mn; Ti and / or Cu, such as, for example, AlFe1.5Mn, AlFeSi or AlFeSiMn alloys having a purity of greater than 97.5%, and preferably greater than 98.5% (%) by weight of aluminum. In particular, the metal layer 4 is made from aluminum, and has a thickness of between 6 and 12 μm, preferably of the order of 12 μm. The faces of the metal layer 4 may have an improved adhesion for the adhesion agent by virtue of a pretreatment tending in particular to increase the surface tension of these faces, for example brushing, chromating, ionization treatment, ozone treatment. , crown, flame or plasma. The adhesive agent layer 5 comprises a copolymer comprising at least 7% by weight of carboxylic and / or carboxylate units, the carboxylic units being in the form of acid or salts. In particular, the carboxylic and / or carboxylate units are present in an amount of between 7% and 19%, and preferably of the order of 9.7% by weight. In particular, layer 5 is a copolymer which comprises at least one first monomer according to the following unit (-CH2-CR3COOR2-) m R3 = H or CH3, R2 = H or unsubstituted, linear or branched alkyl group, such as a methyl, ethyl, propyl or isobutyl group or R2 represents a C4 to C1 cycloalkyl group, and m being chosen such that this first monomer represents between 7 and 19% by weight of the copolymer. In particular, this copolymer comprises at least a second alkylene unit monomer containing from 1 to 10 carbon atoms, and in particular having an ethylenic unit according to the following formula: ## STR2 ## wherein n is chosen such that this second monomer represents between 71 and 92% by weight of the copolymer. Preferably, the copolymer forming layer 5 is a copolymer of ethylene and of ethyl acrylate comprising 9.7% by weight of ethyl acrylate and / or a copolymer of ethylene and of acrylic acid containing 9 7% by weight of acrylic acid. The layer 5 generally has a thickness of between 10 and 40 μm, preferably of the order of 25 μm. Finally, this layer 5 of adhesion agent serves to join the metal layer 4 to the first outer structure 6, the latter is made of a peelable thermoplastic material. For example a material comprising a mixture of polyethylene and polybutene. The proportions of the mixture are defined to have a sufficient difference in separating force (peelability) between a strong weld and a weak weld, when each weld is made at a sufficiently different temperature. For example with such a material, a strong weld performed at 160 ° C opens with a force of 335 N, and a weak weld performed at 100 ° C opens with a force of 210 N. The first outer structure 6 can it itself be made from one or more layers contiguous to each other and made from materials possibly distinct from each other. More particularly, the first outer structure 6 forms a layer of peelable polyethylene. It also has a thickness of between 40 and 150 μm, and preferably of the order of 75 μm. The layers and or respectively structures 2, 3, 5 and 6 can be transparent, translucent or opaque and can be limpid or colored partially or totally. At least one of the outer faces of the material, respectively presented by the outer structures 2 and 6, and preferably the first, may be covered by a printed pattern, itself optionally covered with a lacquer. It is also possible to provide these external faces with a lacquer, this lacquer being able to be printed and / or capable of being printed on the packaging installations, for example by means of UV rays, solvents or laser beams. or electrons. In the case where the outer layers or structures are made from plastics, they can be extruded. In particular, the material is obtained by rolling the layers one over the other. According to a particular embodiment of the multilayer material, this material may also comprise an arrangement of layers and / or structures symmetrical to each other on either side of the metal layer 4.

Preferably, this material can be made in the form of endless material such as rollers, and then cut into sections to be assembled so as to form a multitude of packaging bag 1. The process of manufacturing sachets 1 will be described later. The cosmetic product P intended to be contained in the bag 1, is for example a makeup product such as a foundation, a care product such as a face cream, a coloring product or a hair care product such as a shampoo. The galenic product P may be of any type, such as a powder product, gel, cream or liquid.

In particular, the multilayer material is used to participate in the packaging of cosmetic products such as keratinous fiber coloring compositions, especially compositions for oxidation dyeing containing an alkalinizing agent. Examples of alkalinizing agents that may be mentioned are ammonia, alkaline carbonates, alkanolamines such as mono-, di- and triethanolamines and their derivatives, sodium or potassium hydroxides and wherein R is a propylene residue optionally substituted with a hydroxyl group or a C1-C4 alkyl radical; Ra, Rb, Rc and Rd, which are identical or different, represent a hydrogen atom, a C1-C4 alkyl radical or a C1-C4 hydroxyalkyl radical. According to a preferred embodiment, the basifying agent is chosen from ammonia and / or ethanolamine. In a conventional manner, the compositions for the oxidation dyeing of keratinous fibers, in particular human hair, comprise, in a suitable medium, at least one oxidation base and optionally one or more couplers. As oxidation bases, mention may be made of para-phenylenediamines, bis-phenylalkylenediamines, para-aminophenols, bis-para-aminophenols, ortho-aminophenols, heterocyclic bases and their addition salts. The oxidation base (s) are generally present each in an amount of between 0.001 to 10% by weight approximately of the total weight of the dye composition, preferably between 0.005 and 6%. As couplers present in the dyeing composition, mention may especially be made of meta-phenylenediamines, meta-aminophenols, meta-diphenols, naphthalenic couplers, heterocyclic couplers and their addition salts. In the composition of the present invention, the coupler (s) are each generally present in an amount of between 0.001 and 10% by weight of the total weight of the dye composition, preferably between 0.005 and 6%. In general, the addition salts of the oxidation bases and couplers that can be used in the context of the invention are chosen especially from the addition salts with an acid such as hydrochlorides, hydrobromides, sulphates, citrates, succinates, tartrates, lactates, tosylates, benzenesulfonates, phosphates and acetates and addition salts with a base such as sodium hydroxide, potassium hydroxide, ammonia, amines or alkanolamines. The dye composition may further contain direct dyes. These direct dyes that are useful according to the invention are, for example, chosen from neutral, acidic or cationic nitro-benzene direct dyes, acid or cationic neutral azo direct dyes, direct quinone dyes, and in particular neutral, acidic or cationic anthraquinone dyes, direct dyes. azines, triarylmethane direct dyes, direct indoamine dyes and natural direct dyes. The direct dye (s) preferably represent from 0.001 to 20% by weight approximately of the total weight of the ready-to-use composition and even more preferentially from 0.005 to 10% by weight approximately. At the time of use, the oxidation dye composition as defined above is mixed with an oxidizing agent such as hydrogen peroxide, persalts such as persulfates or an oxidase enzyme such as uricase. or laccase. According to one particular embodiment, the composition is a direct dyeing composition, that is to say free of oxidation and coupling base, containing one or more direct dyes as defined above in a cosmetic medium containing at least one less alkalinizing agent. This composition may also contain an oxidizing agent such as hydrogen peroxide before obtaining a lightening of keratinous fibers. The medium suitable for dyeing also known as dyeing medium 20 is generally water or a mixture of water and at least one organic solvent to solubilize compounds which are not sufficiently soluble in water. The solvents are preferably present in proportions preferably of between 1 and 40% by weight approximately relative to the total weight of the dyeing composition, and even more preferably between 5 and 30% by weight approximately. The dyeing composition may also contain various adjuvants conventionally used in compositions for dyeing hair, such as anionic, cationic, nonionic, amphoteric, zwitterionic surfactants or mixtures thereof, anionic, cationic, nonionic and nonionic polymers. ionic, amphoteric, zwitterionic or mixtures thereof, inorganic or organic thickeners, and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners, antioxidants, penetration agents, sequestering agents, perfumes, buffers , dispersing agents, conditioning agents such as, for example, volatile or non-volatile silicones, modified or unmodified, film-forming agents, ceramides, preserving agents, opacifying agents. The adjuvants above are generally present in an amount for each of them between 0.01 and 20% by weight relative to the weight of the composition.

The dyeing composition may be in various forms, such as in the form of liquids, creams, gels, or in any other form suitable for dyeing keratinous fibers, and especially human hair. Thus each compartment of the bag may contain the same product or different products for example reactive with each other so that they must be mixed just before or at the time of application. For example one compartment may contain an oxidation dye composition and another may contain an oxidizing agent. The advantage of the weak weld with the multilayer material described above is to allow to have a sufficient seal to prevent migration from one compartment to another, the reaction between the two products can emit a gas and cause destruction by explosion of the bag if the pressure becomes too high. Preferably, all the compartments comprise the same product. The use of this sachet is as follows. Optionally, for example if the user is using the product for the first time and if this product has an allergenic factor, the user only tears the opening means 20 between the upper edge and the thin weld to gain access to the amount of useful product for a safety test. Then, when the user wants to use the product, he first determines how much will be needed. This quantity can be determined by the possibility of wanting to mix the product contained in one compartment with the product contained in another compartment, to customize the expected effect, or by the fact that a user needs only one part of the conditioning to meet his need, for example if it is a product for a long hair, a short haired user may need only one part, and will be satisfied to keep the other party for a new application shifted in time. On the other hand, two compartments may comprise a different dye that can be used alone or as a mixture to obtain a third hue.

The user then exerts a pressure close to the weak weld located between the compartments whose products want to be mixed, to open the weak weld concerned. This weak weld is the one closest to the distribution passage. The user can also open several weak welds for the same application. A large compartment formed of several adjacent compartments whose weak welds have been opened then contains the product to be applied. In the case where the compartments comprise different products, the user can knead this large compartment to homogenize the mixture. The user then tears the second opening means to release the dispensing passage 19 in order to extract the mixed product and then apply it. If compartments have not been opened the user can then keep the product for another use during which it will be sufficient to open the remaining weak solder or welds to distribute the product through the dispensing passage 19 already open. The method of manufacturing such a bag will now be described with reference to FIG. 5. The manufacturing method is advantageously implemented by a so-called vertical machine making it possible to form, fill and seal a series of sachet 1 continuously, in order to to obtain high production rates and a low cost. The vertical axis is perpendicular to the longitudinal axis X-X of the bags.

The multilayer sheets of each wall (11, 12) are packaged in coil (not shown). Thus two coils unwind, from the top of the machine, the multilayer sheets forming the front wall 11 and the rear wall 12 of the bag 1 which are brought face to face, the layers forming the first outer structures 6 comprising the peelable thermoplastic material being in contact with each other. look. In the example of Figure 5 the width of each sheet substantially corresponds to the length of a bag. However, the assembly can be repeated in width, creating as many packaging and then multiplying the manufacturing rate by the number of packaging created by width. The unwinding of the coils takes place step by step. Each manufacturing step will now be described. Each step is performed substantially simultaneously to produce a series of bags whose manufacturing steps are shifted one step.

The first step 101 known as "strong welding" makes it possible to definitively bind the two sheets 11 and 12 of the multilayer complex, by making a strong weld 14 on upper and lower edges 17 of the bag 1 positioned laterally in the manufacturing process. The side edges 16 are not welded.

The reels are then unrolled one step. The bag being manufactured is moved down the value of one step, the width of a bag. The second step 102 says "weak welds" makes it possible to perform the weak welds 21 delimiting the compartments along the X-X axis.

The reels are then unrolled one step. The machine then comprises as many product filling ducts 30 as compartments to fill. These rods are fixed, pass through the preformed compartments to previous steps (101, 102) and their end is substantially at the height of this third step 103.

During the third step 103 says "no filling" the filling ducts then deliver the desired amount of product P. This quantity is for example equal in all the compartments, but it is also possible that the volumes delivered are different from one another. The filled bag goes down one more step. The fourth step 104 makes it possible to close the sealed and definitively filled bag by means of a strong weld 14 making it possible to seal the lateral edge 16 which is in the process positioned at the top of the bag. This strong weld also makes it possible to create the sealing of a lateral edge 16 of the next bag positioned at the bottom in the previous step 103. In this respect the filling only begins once this strong welding has been done, that is to say that there is a gap between the execution of the fourth step forming a bag and the third step 103 forming the next bag. Optionally, a fifth step 105 consists of creating a sub-compartment 13a, with the aid of a thin weld 22, then a sixth step 106 in which the opening means or means 20 are made, for example 15 pre-cuts. Lastly, the process of creating a bag is completed by a seventh step 107 of final cut separating the bag of the seventh step 107 from the others still being manufactured in steps 101 to 106. This cutting phase also makes it possible to eliminate the portions 23 of outer walls 20 to the bag and therefore useless on each side of the neck 18 and / or to create any notches for the opening means 20. On complex machines it is possible to make several steps in one, by example the first and second steps can be grouped together and / or the fourth, fifth and sixth steps. Variants of sachets according to the invention are shown in FIGS. 3 and 4. The bag of FIG. 3 comprises a multitude of opening means 20 such as precuts so that the compartments after their emptying can be separated from the non-empty compartments. In this example, each compartment also has a dispensing passage 19.

The bag of Figure 4 has two dispensing passages 19 opposite to facilitate the output of the product from the compartments furthest from the first dispensing passage. The invention is not limited to the illustrated examples. The characteristics of the various examples may especially be combined within non-illustrated variants. The expression "comprising a" shall be understood as meaning "containing at least one" unless the contrary is specified.

Claims (6)

REVENDICATIONS1. Packaging bag of at least one cosmetic product, comprising two flexible sheets secured along their peripheral edge so as to define a peripheral sealing zone and an internal volume, each sheet forms a multilayer complex comprising a metal layer, an agent adhesive composition comprising a copolymer comprising at least 7% by weight of carboxylic and / or carboxylate units, the carboxylic units possibly being in acid or salt form, and a peelable polymer layer bonded to the metal layer via said agent adhesion, the bag is characterized in that it comprises compartments separated by weak welds between the two peelable layers. 2. Bag according to the preceding claim characterized in that the adhesion agent is a copolymer of ethylene and acetic acid. 3. Bag according to one of the preceding claims, characterized in that the peelable polymer layer is made from a mixture comprising polyethylene. 4. Sachet according to the preceding claim, characterized in that the peelable polymer is made from a mixture comprising polybutene. 5. Bag according to one of the preceding claims, characterized in that all the compartments comprise the same cosmetic product. 6. Sachet according to one of claims 1 to 4, characterized in that at least two compartments comprise a cosmetic product different from each other.