AU2005256760B2

AU2005256760B2 - Seals made of a multi-layered material for sealing means, particularly a sealing capsule

Info

Publication number: AU2005256760B2
Application number: AU2005256760A
Authority: AU
Inventors: Jacques Granger
Original assignee: Amcor Flexibles Capsules France SAS
Current assignee: Amcor Flexibles Capsules France SAS
Priority date: 2004-06-11
Filing date: 2005-06-09
Publication date: 2011-04-28
Anticipated expiration: 2025-06-09
Also published as: FR2871446A1; ATE481332T1; AU2005256760A1; NO20070166L; DE602005023611D1; WO2006000706A1; NO338527B1; EP1765688A1; EP1765688B1; ZA200610580B; AR050669A1; FR2871446B1; CA2570372C; ES2352846T3; WO2006000706A8; CA2570372A1

Description

MULTI-LAYER MATERIAL LEAKPROOF SEAL FOR A STOPPER, TYPICALLY FOR A STOPPER CAP FIELD OF THE INVENTION The invention relates to the field of seals associated with stopper means for sealing up containers, typically the field of cork, top or stopper cap seals. 5 STATE OF THE ART A known multi-layer material seal is described in EP 0 970 893 Al wherein EVOH is used as a barrier material. 10 Seals are also known that comprise PVDC as a barrier material. A multi-layer material seal is thus known, for example, which has the following structure: LPDE/EVA/PVDC/EVA/LDPE/EPE/LDPE/EVA/PVDC/EVA/LDPE 15 In this structure, used particularly as a stopper cap seal, the EVA acts as an adhesive layer to bond the LDPE to the PVDC, and EPE denotes an expanded PE. PROBLEMS POSED 20 The problems posed are of several types: - on the one hand, in order to be cost-effective, the seals are typically formed from strip material, typically by cutting with a punch, such that a not insubstantial part of said strip material, in practice 25 typically about 20% in the case of round seals cut "contiguously", forms a skeleton or offcuts which go for waste. In fact, when the strip material intended to 2 form these seals comprises a material including chlorine, typically PVDC, recycling the skeleton, and possible recycling the seals at the end of their life span poses problems, in particular problems of 5 corrosion through the formation of hydrochloric acid, - moreover the presence of PVDC does not allow a seal with a uniform structure to be preserved, - on the other hand, the applicant has conducted stopper tests on bottles of wine for laying down using 10 stopper caps fitted with seals, even though traditionally, bottles of wine for laying down are closed by cork stoppers, and it has noted that, in many cases, the seal used in caps sealing up wine for laying down interfered with the behaviour of the wine over 15 time, in other words, its ageing process. Furthermore, the applicant has found that seals comprising EVOH, although able to form a barrier that is in principle effective or adapted to the ageing of the wine, could not be used as they were unstable in storage, 20 - furthermore, the invention aims to obtain seals that have, with a comparable barrier, a smaller production cost, - finally, the applicant has noted that caps fitted with standard seals were not necessarily 25 adapted, in terms of the level of barrier to oxygen or to steam, to the conservation of wines, since each wine requires a certain barrier level, or a barrier located in a given range of values. Indeed, the ageing of some wines involves a controlled atmosphere exchange, and 30 therefore a pre-set barrier level.

-3 The seals according to the invention aim to resolve these problems, while still providing the required tightness, in other words having no liquid leaks. DESCRIPTION OF THE INVENTION According to a first aspect of the invention, there is provided a multi-layer material 5 leakproof seal intended for use in a stopper means for a container intended to contain a food product, said container optionally being a bottle intended to contain an alcoholic drink and said stopper means being optionally a stopper cap, including a layer C able to withstand resilient axial compression and a layer B forming a barrier to oxygen; wherein a) said layer B forms or comprises a coating of non-organic material, and is of 1o selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen less than 80 cm 3 /m 2 /day; b) said seal comprises a layer S forming a support of said layer B, said support layer S being or not being in contact with said layer C, to give a structure that comprises either a succession of layers C, B and S, a structure shown symbolically as C/B/S in the is case of layer C and adjacent layers B and S, the layer S being intended to be in contact with said food product, or a succession of layers C, S and B, a structure represented symbolically as C/S/B in the case of layer C and adjacent layers S and B, the layer B being intended to be in contact with said product; c) said layer C is formed of a material Me constituted by or comprising a layer of 20 expanded polyolefin.

4 The seals according to the invention resolve the problems posed, while still providing the required tightness, in other words having no liquid leaks. Indeed, these seals are formed from chlorine-free 5 strip material, the barrier B not comprising any PVDC, such that recycling the skeleton, and possibly recycling the seals at the end of their lifespan poses no problem, in particular poses no problem of corrosion through the formation of hydrochloric acid. 10 Moreover, the barrier layer B is a layer which, despite its slight degree of relative thickness compared with the layer C, has a high barrier level, such that recycling the skeleton in the layer C may occur without drawbacks. The layer C is typically at 15 least 1000 times thicker than the barrier layer B, and even sometimes 10,000 times thicker than the barrier layer B. The applicant has conducted tests on stoppering bottles of wine for laying down, using stopper caps 20 fitted with seals according to the invention which ensured the correct ageing of wines, without modifying the properties of these seals over time, and without furthermore encountering the problems with stoppers which can arise more or less randomly with traditional 25 cork stoppers. The invention furthermore makes it possible to obtain a whole series of seals with a smaller production cost, particularly through the possibility of having a more straightforward multi-layer structure 30 for a comparable barrier level.

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5 Finally, the invention makes it possible to obtain a range of seals as a barrier to oxygen or to steam, so as to be able to adapt -the barrier level to each type of wine, with a view to the ageing thereof. 5 DESCRIPTION OF THE FIGURES All the figures relate to the invention. Figure la is a cross-section view of a stopper cap (4) fitted with a multi-layer seal (1, 1') according to 10 the invention. This cap (4) comprises a threaded insert (40) and a metal shell (41). The structure of the multi-layer seal (1, 1') in figure la has been shown in figure lb and corresponds to the symbolic representation C/B/S, corresponding to 15 the succession of layers A, B and S, S being the layer in contact with the liquid. Figures 2a to 8d are similar to figure lb and illustrate a variety of structures of multi-layer seals (1, 1', 1'') according to the invention. The following 20 table shows for each figure the structure of the multi layer seal: Figure number Symbolic representation of multi-layer structure 2a C/I/B/S 2b C/Ad/B/S 2c C/I/Ad/B/S 2d C/I/Ad/S/B 3a S/B/C'/B/S 3b S/B/I/C'/I/B/S 3c S/B/C'/Ad/B/S 3d S/B/Ad/I/C'/I/Ad/B/S 3e S/B/Ad/I/C'/I/B/S 6 3f S/B/C'/I/Ad/B/S 4a C/M/B/S 4b C/Ad/M/B/S 4c C/Ad/M/Ad'/B/S 4d C/M/Ad/B/S 5a S/B/M/C'/M/B/S 5b S/B/C'/I/M/B/S 5c S/B/Ad/M/C'/M/Ad/B/S 5d S/B/Ad/M/C'/I/B/S 5e S/B/C'/M/Ad/B/S 5f S/B/C'/Ad'/M/Ad/B/S 6a S/B/C'/B/S/M 6b S/B/I/C'/I/B/S/M 6c S/B/C'/Ad/B/S/M 6d S/B/Ad/I/C'/Ad'/I/B/S/M 6e M/S/B/Ad/I/C' /I/B/S/M 6f B/S/C'/Ad/M 7a M' or S/B/C'/B/M' or S 7b M' or S/B/I/C'/I/B/M' or S 7c M' or S/B/Ad/C'/Ad/M' 7d M' or S/B/Ad'/I/C/I/Ad/B/M' or S 7e S'/M'/B/Ad/C'/Ad/B/M'/S' 8a M' or S/B/Ad/C'/Ad/B/M' or S/V or P 8b V or P/M' or S/B/Ad/C'/Ad/B/M' or S/V orP 8c V or P/B/S/Ad/C'/Ad/S/B/V or P 8d V or P/M/Ad'/B/S/Ad/C'/S/B/Ad'/M/V or P In figures 2a to 8d, only the layers C, C', B and S have been hatched. The other layers I, Ad, Ad', M etc have not been hatched in the interests of clarity.

7 Figure 9 is a diagrammatic representation of the manufacture of a multi-layer strip material (2) of the type "C/B/E", with a layer C (20) formed by extrusion on a twin layer strip film B/E (23) supplied on a spool 5 (24), and the manufacture of corresponding seals (1, 1', 1'') by cutting out of the strip (2) of multi-layer material C/B/E formed in this manner, the skeleton (3) then being returned to the feed hopper (22) of the extrusion machine (21) and thus recycled in the layer 10 C. Figure 10a is a view from above of a portion of multi-layer material strip (2) after round seals (1, 1') have been cut out, and known as the "skeleton" (3). Figure 10b is a vertical cross-section view of a 15 plane seal (1, 1') of the C/S/B type. Figure 10c is a vertical cross-section view of a thermoformed seal (1, 1') of the C/S/B type. DETAILED DESCRIPTION OF THE INVENTION 20 According to the invention, said barrier layer B may form or comprise a non-organic layer constituted by a coating of SiOx. According to another embodiment of the invention, said barrier layer B may form or comprise a coating of 25 aluminium oxide. According to another embodiment, said barrier layer B may form or comprise a coating of carbon. According to another embodiment of the invention, said barrier layer B may form or comprise a nano 30 particle dispersion of exfoliated platelets of a phyllosilicate clay.

8 Whatever embodiment is selected, said barrier layer B may be of selected thickness or of selected content of non-organic material, to give a seal with permeability to oxygen of less than 5 cm 3 /m 2 /j. 5 Said barrier layer B may be of selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen of between 5 and 10 cm 3 /m 2 /j Said barrier layer B may be of selected thickness 10 or of selected content of said non-organic material, to give a seal with permeability to oxygen of between 10 and 20 cm 3 /m 2 /j Said barrier layer B may be of selected thickness or of selected content of said non-organic material, to 15 give a seal with permeability to oxygen of between 20 and 40 cm3/m2/j. Said barrier layer B may be of selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen of over 40 20 cm3/m 2 /j and typically of up to 80 cm 3/m 2/j. Indeed, it is important to have available a range of seals with different ranges of permeability to oxygen, insofar as each type of wine may require, for optimum conservation and ageing, a seal which provides 25 a more or less significant level of gaseous exchange with the outer atmosphere. Generally speaking, the level of gaseous exchange will be less for white wines than for red wines. According to the invention, said barrier layer B 30 may have a thickness of between 10 nm and 250 nm when said non-organic material is selected from a coating of 9 SiOx, or a coating of aluminium oxide or a coating of carbon. Said barrier layer B may also be formed by a dispersion of exfoliated nano-particles in a resin or a 5 plastic material with a thickness of between 1 pm and 30 pm. According to the invention said layer C may have a thickness Ec typically between 0.5 mm and 2.5 mm. Said layer C may be formed of a material Mc 10 constituted by or comprising a layer of expanded polyolefin typically expanded PE or EPE. Said layer C may be constituted by or comprise a layer of thermoplastic material with density between 200 and 500 kg/M 3 . 15 Typically, said layer C may be a layer of expanded or cellular polyolefin, typically a layer of expanded PE or EPE, with density between 350 kg/m 3 and 450 kg/M 3 . Said layer C may be constituted by or comprise a 20 layer of elastomer, typically SEBS or silicon. According to the invention, said support layer S may be formed out of the material Ms selected from a polyolefin or a PET, typically a PP, of thickness Es typically between 10 pm and 50 pm. See figure lb. 25 As is shown in diagrammatic form particularly in figure 2a, an intermediate layer I may be interposed between said layer C and said layer B, said intermediate layer I being a layer of polyolefin, and typically a layer of PE, of thickness E 1 typically 30 between 10 pm and 50 pm, to give for said multi-layer 10 material a structure represented symbolically as C/I/B/S or as C/I/S/B. Indeed, it may be useful or necessary to manufacture the multi-layer material I/B/S separately, 5 since the layer I is able to act to protect the barrier layer B and/or provide the connection with the layer C. Depending particularly on the nature of said layer B, and as shown in diagrammatic form in figures 2b and 2c, a layer of adhesive Ad may be interposed between 10 said layer B and said layer C or said layer I, said adhesive layer Ad typically having a thickness EA of less than 5 pim, to give for said multi-layer material a structure represented symbolically as C/Ad/B/S or C/I/Ad/B/S or C/Ad/S/B or C/I/Ad/S/B or C/Ad/I/B/S or 15 C/Ad/I/S/B. According to another embodiment of the invention shown in figures 3a to 3f and 6a to 8d, said layer C may be a central layer C' possibly forming a plane of symmetry in respect of said multi-layer material, to 20 give for said multi-layer material structures selected from: a) S/B/C'/B/S,B/S/C'/S/B,S/B/C'/B/S, as shown in figure 3a, b) structures comprising at least one intermediate 25 layer I, in particular: S/B/I/C'/I/B/S,B/S/I/C'/I/S/B, S/B/I/C'/I/S/B,S/B/C'/I/B/S,B/S/C'/I/S/B,S/B/C'/I/S/B, S/B/I/C'/S/B, as shown in figure 3b, c) structures comprising at least one adhes-ive layer Ad, in particular: S/B/Ad/C'/Ad/B/S, 30 B/S/Ad/C'/Ad/S/B, S/B/C'/Ad/B/S,B/S/C'/Ad/S/B, as shown in figure 3c, ,11 d) structures comprising at least one adhesive layer Ad and an intermediate layer I, in particular: S/B/Ad/I/C' /I/Ad/B/S,B/S/Ad/I/C' /I/Ad/S/B, S/B/I/Ad/C' /A d/I/B/S,B/S/I/Ad/C'/Ad/I/S/B,S/B/I/C'/I/Ad/B/S,B/S/I/C' 5 /I/Ad/S/B,S/B/I/C'/Ad/I/B/S,B/S/I/C'/Ad/I/S/B, as shown in figures 3d to 3e. As shown in the portions of figures 3a and 5a between the dotted lines A and A', said layer C' may be formed by the layers C/Ad''/C, Ad'' being another 10 adhesive layer, the layer Ad'' and said adhesive layers Ad and Ad' being able to be formed of one adhesive of the same type or of adhesives of different types. As shown diagrammatically in figures 4a to 6e, said seal (1, 1', 1'') may comprise a metal layer M, 15 typically in the form of a metal film MF made of Sn or Al or in the form of a metal layer MD formed by vacuum coating of metal, typically a layer of Cr or Al. According to one embodiment of the invention, said metal layer M may be interposed between said barrier 20 layer B and said layer C or said layer C', possibly by means of an adhesive layer Ad or an adhesive layer Ad', different or not different from said adhesive layer Ad, in such a way that a part of said seal comprises a multi-layer structure part selected from: 25 a) C or C'/M/B/S, C or C'/M/S/B, as shown in figures 4a or 5a, b) structure parts comprising an intermediate layer I, in particular: C or C'/I/M/B/S, C or C'/I/M/S/B, as shown in figures 4b or 5b, 30 c) structure parts comprising at least one adhesive layer Ad, in particular: C or C'/Ad/M/B/S, C 12 or C'/Ad/M/S/B, C or C'/Ad'/M/Ad/B/S, C or C'/Ad'/M/Ad/S/B, as shown in figures 4c, 5c, 5e and 5f, d) structure parts comprising at least one intermediate layer I and an adhesive layer Ad and/or an 5 adhesive layer Ad', in particular: C or C'/I/M/Ad/B/S, C or C'/I/Ad/M/B/S, C or C'/I/Ad/M/S/B, as shown in particular in figures 4d and 5d. According to another embodiment of the invention, said barrier B may be included between said metal layer 10 M and said layer C or C', possibly by using an adhesive layer Ad or an adhesive layer Ad', different or not different from said adhesive layer Ad, in such a way that a part of said seal comprises a multi-layer structure part selected from: 15 a) C or C'/B/S/M, C or C'/S/B/M, as shown in figure 6a, b) structure parts comprising an intermediate layer I, in particular: C or C'/I/B/S/M, C or C'/I/S/B/M, as shown in figure 6b, 20 c) structure parts comprising an adhesive layer Ad, in particular: C or C'/Ad/B/S/M, C or C'/Ad/S/B/M, as shown in figure 6c, d) structure parts comprising at least one intermediate layer I and an adhesive layer Ad and/or 25 Ad', in particular: C or C'/Ad/I/B/S/M, C or C'/I/Ad/B/S/M, C or C'/Ad/I/S/B/M, C or C'/I/Ad/S/B/M or C'/I/Ad/S/B/Ad'/M, as shown in figures 6d and 6e. Whatever the embodiment of the invention, said metal film ME may be constituted by a film of Sn or Al, 30 with a thickness Em of between 5 pm and 20 vim, and typically a thickness of 10 im.

13 Said metal layer MD formed by vacuum deposition of metal may be a vacuum metal plated layer with a thickness of between 10 nm and 1000 nm, deposited on said support S or on another support S' , as shown in 5 figure 4d. According to another embodiment of the invention shown in figures 7a to 7e, said layer S may be replaced by a layer M', said layer M' being selected from a metal film MF Of Sn or Al or a metal layer MD formed by 10 vacuum deposition of metal, typically a layer of Cr or of Al, on a support film S', to give, for said multi layer material, structures selected from: a) M'/B/C'/B/M',B/M'/C'/M'/B,M/B/C'/B/M', as shown in figure 7a, 15 b) structures comprising at least one intermediate layer I, in particular: M'/B/I/C'/I/B/M', B/M'/I/C'/I/M'/B,M'/B/I/C'/I/M'/B,M'I/B/C'/I/B/M',B/M'/C '/I/M'/B,M'/B/C'/I/M'/B,M'/B/I/C'/M'/B, as shown in figure 7b, 20 c) structures comprising at least one adhesive layer Ad, in particular: M/B/Ad/C'/Ad/B/M',B/M'/Ad/C'/Ad/M'/B, M'/B/C'/Ad/B/M',B/M'/C'/Ad/M'/B, as shown in figure 7c or 7e, 25 d) structures comprising at least one adhesive layer Ad and one intermediate layer I, in particular: M'/B/Ad/I/C'/I/Ad/B/M',B/M/Ad/I/C'/I/Ad/M'/B,M'/B/I/Ad/ C'/Ad/I/B/M',B/M'/I/Ad/C'/Ad/I/M'/B,M'/B/I/C'/I/Ad/B/M' ,B/M'/I/C'/I/Ad/M'/B,M'/B/I/C'/Ad/I/B/M',B/M'/I/C'/Ad/I 30 /M'/B, as shown in figure 7d.

14 However, said layer S may be replaced by a layer M' , said layer M' being selected from a metal film MF of Sn or Al or a layer of metal MD formed by vacuum deposition of metal, typically a layer of Cr or Al, on 5 a support film S', in such a way that a part of said seal comprises a part of said multi-layer structure selected from: a) C or C'/M'/B/C or C'/B/M', as shown in figure 7a, 10 b) structure parts comprising an intermediate layer I, in particular: C or C'/I/M'/B, C or C'/I/B/M', as shown in figure 7b, c) structure parts comprising an adhesive layer Ad, in particular: C or C'/Ad/M'/B, C or C'/Ad/B/M', as 15 shown in figure 7c or 7e, d) structure parts comprising at least one adhesive layer Ad and one intermediate layer I, in particular: C or C'/I/Ad/M'/B, C or C'/Ad/I/B/M',C,C or C'/I/Ad/B/M', C or C'/Ad/I/M'/B, C or C'/I/Ad/M'/B, as 20 shown in figure 7d. As shown in figures 8a to 8d, when said layer B or said layer M or M' is an outer layer intended to be in contact with the food product, said layer B or said layer M or M' may be coated with a layer of varnish V, 25 typically a food varnish, in such a way that said seal has a structure comprising externally "/B/V" or "/M(M' ) /V". According to another embodiment of the invention, and as shown in figures 8a to 8d, when said layer B or 30 said layer M or M' is an outer layer intended to be in contact with said food product, said layer B or said 15 layer M or M' may be coated with a protective layer P, typically of polyolefin, possibly anchored by an adhesive layer Ad''', in such a way that said seal has a structure ending in "I/B/P" or in "/M(M')/P", or in 5 B/Ad'''/P'' or in "/M(M')/Ad'''/P''. Typically, said thickness Ec of said layer C or of said layer C' may represent from 70% to 99% of the total thickness Ej of said seal. See figure lb. As shown particularly in figure 10b, said seal (1) 10 may form a plane seal (1') typically obtained by cutting said multi-layer material in a strip or typically two-dimensional format. However, as shown in figure 10c, said seal (1) may form a shaped seal (1'') typically obtained by 15 thermoforming said multi-layer material in a strip or two-dimensional format. Another purpose of the invention is constituted by container stopper means comprising a seal (1, 1', 1'') according to the invention. 20 This stopper means may comprise a stopper cap (4) fitted with a seal (1, 1', 1'') according to the invention, said container typically being a bottle intended to contain, as a food product, an alcoholic drink, typically wine. 25 As shown in figure la, said stopper cap (4) may comprise a typically threaded plastic material insert (40), said seal (1, 1', 1'') being anchored to said insert (40), and an outer shell (41) of metal, typically of Al or Sn, or metallised plastic, or 30 plastic.

16 Another purpose of the invention is constituted by the use of a seal (1, 1', 1'') according to the invention in a container stopper means, and more especially by this use in the event of said container 5 being a bottle intended to contain an alcoholic drink, typically wine. Another purpose of the invention is constituted by the method for manufacturing a seal according to the invention. 10 In this method, and as shown diagrammatically in figure 9: a) a multi-layer component B/S or I/B/S or I/Ad/B/S or B/M' may be supplied or formed depending on circumstances, in the form of a strip material BB, 15 b) said layer C or C' may be formed, typically by extrusion of said material Mc, forming a strip Bc, c) a strip Bj of said multi-layer material may be formed by laminating said strip BB onto at least one surface of said strip Bc, 20 d) said seals may be cut from said strip Bj of said multi-layer material, forming a skeleton (3) or waste which are recycled in said material Mc intended to form said layer C or C', so as to give a low material cost for said seal. 25 A portion of a skeleton (3) of this kind has been shown in figure 10a. EMBODIMENT EXAMPLES 20 pim OPP trade films were supplied coated with a 30 layer of SiOx of between 20 nm and 150 nm.

17 12 pm PET trade films were also supplied coated with a layer of SiOx of between 20 nm and 150 nm. These films are films in spools 690 mm in width or breadth. 5 Thus, for all tests, the layer B corresponds to a layer of SiOx, and the layer S is either 12 im PET, or 20 pim OPP. A - Manufacturing multi-layer structures or films 10 Al. Manufacturing the structure I or C/B/S The layers C or C' were formed by extruding 690 mm wide layers of expanded PE or EPE, to form directly the multi-layer film or material EPE/SiOx/PET or OPP, i.e. symbolically C/B/S, the B/S film bonding directly onto 15 the layer C at the exit of the extruder prior to being cooled. See figure lb. To form the structure C/B/S in a strip (2), the device shown diagrammatically in figure 6 was used. The layer C of EPE had a density of 0.380 (density 20 of 380 kg/m 3 ) and a thickness of 1.8 mm. A2. Manufacturing the structures 2a to 2c Structure 2a = C/I/B/S (see figure 2a), Structure 2b = C/Ad/B/S (see figure 2b), 25 Structure 2c = C/I/Ad/B/S (see figure 2c), Structure 2d = C/I/Ad/S/B (see figure 2d), For the layer I, a 20 pm thick layer of LDPE was taken, in these tests and generally in all tests including a layer I. 30 The layer Ad is a layer of adhesive for 2 pm thick trade PE.

18 To manufacture the structure 2a, the layer I was extruded between the layer C and the film B/S. To manufacture the structure 2b, the surface B of the film B/S was coated with a coating of adhesive 5 layer Ad before being overlaid onto the layer C. To manufacture the structure 2c, the structure I/Ad/B/S was formed first by using as the layer I a film of LDPE of the same thickness (20 im), then this structure was assembled with the layer C at the exit of 10 the extruder. To manufacture the structure 2d, the surface S of the film B/S was coated with a coating of adhesive layer Ad before being overlaid onto the layer C. 15 A3. Manufacturing the structures 3a to 3f Structure 3a = S/B/C'/B/S (see figure 3a), Structure 3b = S/B/I/C'/I/B/S (see figure 3b), Structure 3c = S/B/C'/I/B/S, Structure 3d = S/B/Ad/I/C'/I/Ad/B/S (see figure 3d), 20 Structure 3e = S/B/Ad/I/C'/I/B/S (see figure 3e), Structure 3f = S/B/C'/I/Ad/B/S (see figure 3f), Structure 3a was formed like structure 1, by placing B/S on either side of the layer C, becoming C'. Structure 3b was formed like structure 2a by 25 placing I/B/S on either side of the layer C, becoming C'. Structure 3c is a mixed structure which was formed by assembling on one surface of the central layer C, the structural component I/B/S as in structure 2b and 30 by assembling on the other surface S/B as in structure 1, the layer C then becoming the layer C'.

19 Structure 3d was formed like structure 2c, by placing I/Ad/B/S on either side of the layer C, becoming C'. 5 A4. Manufacturing the structures 4a to 4d Structure 4a = C/M/B/S (see figure 4a) Structure 4b = C/I/M/B/S (see figure 4b) Structure 4c = C/Ad/M/Ad'/B/S (see figure 4c) Structure 4d = C/I/M/Ad/B/S (see figure 4d) 10 Structure 4e = C/M/Ad/B/S Structure 4f = C/S'/M/Ad/B/S (see figure 4d) Structure 4g = C/I/M/S/B For layer M was used: - a layer of metal plated by vacuum deposition of 500 15 nm thick aluminium, in the case of tests 4a, 4f and 4g the metal layer M being a vacuum deposition layer MD formed on the film B/S in the case of test 4a and 4b, on the support S' (15 pm of PE) in the case of test 4f, and on the layer I in the case of test 4g, 20 - a layer of tin or aluminium from 6 to 10 pm thick forming a film MF for the other tests. The structure 4a was formed by vacuum metal plating the film B/S to obtain the structure M/B/S, then by assembling it with the layer C before it is 25 cooled. In the case of structure 4b, the structure M/B/S was assembled with the layer C with a 2 pm adhesive layer Ad'. The structure 4c was formed by assembling a layer 30 of Sn (M) with the film B/S and with the layer C using two layers of adhesive Ad and Ad', typically identical.

20 The structure 4d was formed by assembling a layer of Sn (M) with the film B/S using a layer of adhesive Ad, the structure M/Ad/B/S then being assembled with the layer C before it is cooled. 5 The structure 4e was formed by poly-laminating the metal strip M between the layer C and the film B/S, using an adhesive layer Ad. The structure 4f was formed by forming the film S'/M by vacuum deposition of metal, and by poly 10 laminating it between the layer C and the film B/S, using an adhesive layer. The structure 4g was formed by forming the film I/M by vacuum deposition of metal and by directly poly laminating the film I/M between the layer C and the 15 film S/B. A5. Manufacturing the structures 5a to 5i Structure 5a = S/B/M/C'/M/B/S (see figure 5a) Structure 5b = S/B/C'/I/M/B/S (see figure 5b) 20 Structure 5c = S/B/Ad/M/C'/M/Ad/B/S (see figure 5c) Structure 5d = S/B/Ad/M/C'/I/B/S (see figure 5d) Structure 5e = S/B/C'/M/Ad/B/S (see figure 5e) Structure 5f = S/B/C'/Ad'/M/Ad/B/S (see figure 5f) Structure 5g = S/B/C'/M/S/B 25 Structure 5h = B/S/C'/M/S/B Structure Si = B/S/M/C'/M/S/B This series of structures is similar to the one denoted 3a to 3f. The structure 5a was formed by forming the film 30 S/B/M by vacuum deposition of metal on the layer B of 21 the film B/S, then by placing it on either side of the layer C', by hot polylaminating. The structure 5b is asymmetrical and was formed by co-extruding the component C'/I and by assembling by 5 polylaminating the film M/B/S of the structure 5a, and the film B/S. The structure 5c is symmetrical and was formed by polylaminating on either side of the layer C', a metal layer MF (6 pn Al or Sn metal film) and the film B/S 10 using an adhesive layer Ad. The component M/Ad/B/S may be formed first. The structure 5d is asymmetrical and was formed, by co-extruding the component C'/I and by polylaminating on one surface the film B/S, and the 15 metal layer MF, another film S/B being assembled to the metal layer MF using an adhesive layer Ad. The component S/B/Ad/M (identical to M/Ad/B/S) which was then laminated onto the co-extruded component C/I, was also formed first. 20 The structure 5e was formed from the film S/B and from the structure M/Ad/B/S (see structure 5c and 5d), and by extruding the layer C' between the film S/B and the structure M/Ad/B/S. The structure 5f differs from the structure 5e 25 through the presence of an adhesive layer Ad' between the layer C' and the component M/Ad/B/S. The structure 5g is formed from the film S/B and from the component M/S/B formed by vacuum deposition of a metal layer MD onto the surface S of the film S/B, by 30 polylaminating the extruded layer C' between the film S/B and the film M/S/B.

22 The structure 5h was formed by polylaminating the extruded layer C' between the film B/S (=film S/B) and the film M/S/B. The structure 5i was formed by polylaminating the 5 extruded layer C' between the films M/S/B. A6. Manufacturing the structures 6a to 6f Structure 6a = S/B/C'/B/S/M Structure 6b = S/B/I/C'/I/B/S/M 10 Structure 6c = S/B/C'/Ad/B/S/M Structure 6d = S/B/Ad/I/C'/Ad'/I/B/S/M Structure 6e = M/S/B/Ad/I/C'/I/B/S/M Structure 6f = B/S/C'/Ad/M To manufacture the structures 6a to 6e, first of 15 all the component B/S/M was formed by metal plating the surface S of the film B/S, and a process was then used similar to the one used for previous similar structures. To manufacture the structure 6f, the film B/S was 20 laminated onto one surface of the extruded layer C' and a metal film M was bonded onto the other surface using a layer of adhesive Ad. In the same way, the structure 6g was also formed similar to the structure 6f: B/S/Ad/C'/Ad/M. 25 A7. Manufacturing the structures 7a to 7e Structure 7a = M'/B/C'/B/M' or S Structure 7b = M'/B/I/C'/I/B/M' or S Structure 7c = M'/B/Ad/C'/Ad/M' or S 30 Structure 7d = M'/B/Ad'/I/C/I/Ad/B/M' or S Structure 7e = S'/M'/B/Ad/C'/Ad/B/M'/S' 23 To manufacture these structures, the component M'/B is formed. To do this, a metal layer M' was used as a support for the barrier layer B, this metal layer M' replacing the support layer S. This metal layer M' 5 is a metal layer of Sn or Al with a thickness of between 6 and 10 im. The structures 7a to 7d comprise on either side of the layer C', either the same component M'/B, or the component M'/B on one side of the layer C' and the 10 component B/S on the other side of the layer C'. In the case of the structure 7e, the metal layer M' is formed by a layer of metal plating MD, formed on a support S' (15 pm film of PE or PET). To manufacture the structures 7a to 7e, a process 15 was used similar to the one used for previous similar structures. A8. Manufacturing the structures 8a to 8d Structure 8a = M'/B/Ad/C'/Ad/B/M'/V or P 20 Structure 8b = V or P/M'/B/Ad/C'/Ad/B/M'/V or P Structure 8c = V or P/B/S/Ad/C'/Ad/S/B/V or P Structure 8d = V or P/M/Ad'/B/S/Ad/C'/S/B/Ad'/M/V or P These structures 8a to 8d were manufactured either by applying a layer of varnish V, typically at 3 g/m 2 , 25 to the relevant structures, or by applying a protective film P, typically by calendering. B - Manufacturing seals Plane seals (1, 1') were obtained by cutting with 30 a punch from the multi-layer strip material (2) obtained previously.

24 In the case of round seals (1, 1') a skeleton (3) is left as shown in figure 10a, a skeleton which is typically recycled, as shown diagrammatically in figure 9. 5 In the case of a multi-layer structure not comprising a layer of tin, the skeleton (3) obtained after cutting out the seals was recycled in the layer C or C'. 10 C - Results obtained These plane seals (1, 1') had a great variety of levels of permeability to gases and typically to oxygen and a great variety of thickness, so as to give seals belonging to different categories as follows: 15 Category I: < 5 cm 3/m2/j Category II: 5-10 cm 3 /m 2 /j Category III: 10-20 cm 3 /m 2 /j Category IV: 20-40 cm 3 /m 2 /j Category V: 40-80 cm 3 /m 2 /I 20 These seals were placed into stopper caps (4) of the same type as the one shown in figure la. These caps (4) typically comprise an outer metal shell (41) able to be inserted under the finish of the bottle to be sealed, and an inner insert (40) of 25 plastic material, an insert (40) which is typically threaded so as to engage with the threading of the finish. The seal (1, 1') is placed inside the insert (40) and is typically held in place by a radial groove or 30 radial projections (42) formed inside the insert (40).

25 ADVANTAGES OF THE INVENTION The invention allows a great variety of seals adapted to each type of wine for packaging to be obtained in a cost-effective way. 5 The invention thus allows screw capping to be developed to replace the use of corks as the traditional means for stoppering wine bottles. KEY TO REFERENCE NUMBERS SEAL SEAL plane l' SEAL shaped (heat formed) l'' MULTI-LAYER MATERIAL 2 MULTI-LAYER MATERIAL STRIP 2' EXTRUDED LAYER "C" 20 EXTRUDER 21 FEEDER FOR 20 22 STRIP OF "B/S" or B/M' 23 SPOOL OF "B/S" or B/M' 24 SKELETON of 2 recycled at 22 3 STOPPER CAP 4 THREADED INSERT 40 OUTER SHELL 41 MEANS of anchoring 1 to 40 42 10

Claims

1. Leakproof seal made of a multi-layer material intended to be used in a stopper means for a container intended to contain a food product, said container optionally being a bottle intended to contain an alcoholic drink and said stopper means optionally being a 5 stopper cap, including a layer C able to withstand resilient axial compression, and a layer B forming a barrier to oxygen, wherein: a) said layer B forms or comprises a coating of non-organic material, and is of selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen less than 80 cm 3 /m 2 /day; 10 b) said seal comprises a layer S forming a support of said layer B, said support layer S being or not being in contact with said layer C, to give a structure that comprises either a succession of layers C, B and S, a structure represented symbolically as C/B/S in the case of layer C and adjacent layers B and S, the layer S being intended to be in contact with said food product, or a succession of layers C, S and B, a structure represented is symbolically as C/S/B in the case of layer C and adjacent layers S and B, the layer B being intended to be in contact with said food product, c) said layer C is formed of a material M, constituted by or comprising a layer of expanded polyolefin.

2. Seal according to claim 1 wherein said coating of said barrier layer B forms or 20 comprises a non-organic coating constituted by a coating of SiO,,.

3. Seal according to any one of claims 1 to 2 wherein said coating of said barrier layer B forms or comprises a coating of aluminium oxide.

4. Seal according to any one of claims 1 to 3 wherein said coating of said barrier layer B forms or comprises a coating of carbon. 25

5. Seal according to any one of claims 1 to 4 wherein said barrier layer B forms or comprises a nano-dispersion of exfoliated platelets of phyllosilicate clay.

6. Seal according to any one of claims 1 to 5 wherein said barrier layer B is of selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen of less than 5 cm 3/m2/j. 30

7. Seal according to any one of claims I to 5 wherein said barrier layer B is of selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen of between 5 and 10 cm 3 /m 2 /j.

8. Seal according to any one of claims 1 to 5 wherein said barrier layer B is of selected thickness or of selected content of said non-organic material, to give a seal with 35 permeability to oxygen of between 10 and 20 cm 3 /m 2 /j. - 27

9. Seal according to any one of claims 1 to 5 wherein said barrier layer B is of selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen of between 20 and 40 cm 3 /m 2 /j.

10. Seal according to any one of claims 1 to 5 wherein said barrier layer B is of s selected thickness or of selected content of said non-organic material, to give a seal with permeability to oxygen of over 40 cm 3 /m 2 /day and optionally of up to 80 cm 3 /m 2 /day.

11. Seal according to any one of claims 1 to 10 wherein said barrier layer B has a thickness of between 10 nm and 250 nm when said non-organic material is selected from a coating of SiOx,, or a coating of aluminium oxide or a coating of carbon. 10

12. Seal according to any one of claims I to 10 wherein said barrier layer B is formed by a dispersion of exfoliated nano-particles in a layer of resin or plastic material with a thickness of between 1 pm and 30 pm.

13. Seal according to any one of claims I to 12 wherein said layer C has a thickness Ec between 0.5 mm and 2. 5 mm. is

14. Seal according to any one of claims I to 13 wherein said layer C is constituted by or comprises a layer of thermoplastic material with a density between 200 and 500 kg/m 3 .

15. Seal according to any one of claims 1 to 14 wherein said layer C is constituted by or comprises a layer of elastomer. 20

16. Seal according to any one of claims I to 15 wherein said support layer S is formed out of a material M, selected from a polyolefin, a PET, a PA, of thickness Es optionally between 10 pm and 50 jim.

17. Seal according to any one of claims 1 to 16 wherein an intermediate layer I is interposed between said layer C and said barrier layer B, said intermediate layer I being a 25 layer of polyolefin, of thickness El optionally between 10 pm and 50 pm, to give for said multi-layer material a structure represented symbolically as C/I/B/S or as C/I/S/B.

18. Seal according to any one of claims 1 to 17 wherein a layer of adhesive Ad is interposed between said layer B and said layer C or, when the seal is according to claim 17, said layer I, said adhesive layer optionally having a thickness EA of less than 5 jim, to 30 give for said multi-layer material a structure represented symbolically as C/Ad/B/S or C/I/Ad/B/S or C/Ad/S/B or C/I/Ad/S/B or C/Ad/I/B/S or C/Ad/I/S/B.

19. Seal according to any one of claims 1 to 18 wherein said layer C is a central layer C' optionally forming a plane of symmetry in respect of said multi-layer material, to give for said multi-layer material structures selected from: 35 a) S/B/C'/B/S, B/S/C'/S/B, S/B/C'/B/S, -28 b) structures comprising at least one intermediate layer I, in particular: S/B/L/C'/I/B/S, B/S/I/C'/I/S/B, S/B/I/C'/I/S/B, S/B/C'/I/B/S, B/S/C'/I/S/B, S/B/C'/I/S/B, S/B/I/C'/S/B, c) structures comprising at least one adhesive layer Ad, in particular: 5 S/B/Ad/C'/Ad/B/S, B/S/Ad/C'/Ad/S/B, S/B/C'/Ad/B/S, B/S/C'/Ad/S/B, d) structures comprising at least one adhesive layer Ad and an intermediate layer I, in particular: S/B/Ad/I/C'/I/Ad/B/S, B/S/Ad/I/C'/I/Ad/S/B, S/B/I/Ad/C'/Ad/I/B/S, B/S/I/Ad/C'/Ad/I/S/B, S/B/I/C'/I/Ad/B/S, B/S/I/C'/I/Ad/S/B, S/B/I/C'/Ad/L/B/S, io B/S/I/C'/Ad/I/S/B.

20. Seal according to claim 19 wherein said layer C' is formed by the layers C/Ad"/C, Ad" being another adhesive layer, said adhesive layer Ad" and said adhesive layers Ad and Ad' being able to be formed of one adhesive of the same type or of adhesives of different types. 15

21. Seal according to any one of claims I to 20 comprising a metal layer M, optionally in the form of a metal film MF of Sn or Al or in the form of a metal layer MD formed by vacuum deposition of metal, optionally a layer of Cr or Al.

22. Seal according to claim 21 wherein said metal layer M is interposed between said barrier layer B and said layer C or, when the seal is according to claim 19 or 20, said 20 layer C', possibly by means of an adhesive layer Ad or an adhesive layer Ad', different or not different from said adhesive layer Ad, in such a way that a part of said seal comprises a multi-layer structure part selected from: a) C or C'/M/B/S, C or C'/M/S/B, b) structure parts comprising an intermediate layer I, in particular: 25 C or C'/I/M/B/S, C or C'/I/M/S/B, c) structure parts comprising at least one adhesive layer Ad, in particular: C or C'/Ad/M/B/S, C or C'/Ad/M/S/B, C or C'/Ad'/M/Ad/B/S, C or C'/Ad'/M/Ad/S/B, d) structure parts comprising at least one intermediate layer I and an adhesive 30 layer Ad and/or an adhesive layer Ad', in particular: C or C'/I/M/Ad/B/S, C or C'/I/Ad/M/B/S, C or C'/I/Ad/M/S/B.

23. Seal according to claim 21 wherein said barrier layer B is included between said metal layer M and said layer C or C', possibly by using an adhesive layer Ad or an adhesive layer Ad', different or not different from said adhesive layer Ad, in such a way 35 that a part of said seal comprises a multi-layer structure part selected from: - 29 a) C or C'/B/S/M, C or C'/S/B/M, b) structure parts comprising an intermediate layer I, in particular: C or C'/I/B/S/M, C or C'/I/S/B/M, c) structure parts comprising an adhesive layer Ad, in particular: s C or C'/Ad/B/S/M, C or C'/Ad/S/B/M, d) structure parts comprising at least one intermediate layer I and an adhesive layer Ad and/or Ad', in particular: C or C'/Ad/I/B/S/M, C or C'/I/Ad/B/S/M, C or C'/Ad/Il/S/B/M, C or C'/I/Ad/S/B/M or C'/I/Ad/S/B/Ad'/M. 10

24. Seal according to any one of claims 21 to 23 wherein said metal film MF is constituted by a film of Sn or Al, with a thickness EM of between 5 pm and 20 gm.

25. Seal according to any one of claims 21 to 23 wherein said metal layer MD formed by vacuum deposition of metal is a vacuum metal plated layer with a thickness of between 10 rn and 1000 nm , deposited on said support S or on another support S'. 15

26. Seal according to any one of claims I to 20 wherein said layer S is replaced by a layer M', said layer M' being selected from a metal film MF of Sn or Al or a metal layer MD formed by vacuum deposition of metal, optionally a layer of Cr or of Al, on a support film S', to give, for said multi-layer material, structures selected from: a) M'/B/C'/B/M', B/M'/C'/M'/B, M'/B/C'/B/M', 20 b) structures comprising at least one intermediate layer I, in particular: M'/B/I/C'/I/B/M', B/M'/I/C'/I/M' /B, M'/B/I/C'/I/M'/B, M'/B/C'/I/B/M', B/M'/C'/I/M'/B, M'/B/C'/I/M'/B, M'/B/I/C'/M'/B, c) structures comprising at least one adhesive layer Ad, in particular: M/B/Ad/C'/Ad/B/M', B/M'/Ad/C'/Ad/M'/B, M'/B/C'/Ad/B/M', B/M'/C'/Ad/M'/B, 25 d) structures comprising at least one adhesive layer Ad and one intermediate layer I, in particular: M'/B/Ad/I/C'/I/Ad/B/M', B/M/Ad/Il/C'/I/Ad/M'/B, M'/B/I/Ad/C'/Ad/I/B/M', B/M'/I/Ad/C'/Ad/I/M'/B, M'/B/I/C'/I/Ad/B/M', B/M'/I/C'/I/Ad/M'/B, M'/B/I/C'/Ad/I/B/M', B/M'/I/C'/Ad/I/M'/B. 30

27. Seal according to any one of claims 1 to 20 wherein said layer S is replaced by a layer M', said layer M' being selected from a metal film MF of Sn or Al or a metal layer MD formed by vacuum deposition of metal, optionally a layer of Cr or Al, on a support film S', in such a way that a part of said seal comprises a part of said multi-layer structure selected from: 35 a) C or C'/M'/B, C or C'/B/M', -30 b) structure parts comprising an intermediate layer I, in particular: C or C'/I/M'/B, C or C'/I/B/M', c) structure parts comprising an adhesive layer Ad, in particular: C or C'/Ad/M'/B, C or C'/Ad/B/M', 5 d) structure parts comprising at least one adhesive layer Ad and one intermediate layer I, in particular: C or C'/I/Ad/M'/B, C or C'/Ad/I/B/M', C or C'/I/Ad/B/M', C or C'/Ad/I/M'/B, C or C'/I/Ad/M'/B.

28. Seal according to any one of claims 1 to 27 wherein, when said layer B or said io layer M or M' is an outer layer intended to be in contact with said food product, said layer B or said layer M or M' is coated with a layer of a varnish V, optionally a food varnish, in such a way that said seal has a structure comprising externally "/B/V" or "/M(M')/".

29. Seal according to any one of claims 1 to 27 wherein, when said layer B or said layer M or M' is an outer layer intended to be in contact with said food product, said layer is B or said layer M or M' is coated with a protective layer P, optionally of polyolefin, possibly anchored by an adhesive layer Ad"', in such a way that said seal has a structure ending in "/B/P" or in "/M(M')/P", or in B/Ad"'/P" or in "/M(M')/Ad"'/P".

30. Seal according to any one of claims 1 to 29 wherein said thickness Ec of said layer C or of said layer C' represents from 70% to 99% of the total thickness Ej of said 20 seal.

31. Seal according to any one of claims 1 to 30 forming a plane seal obtained by cutting said multi-layer material in a strip or in an optionally two-dimensional format.

32. Seal according to any one of claims I to 30 forming a shaped seal optionally obtained by thermoforming said multi-layer material in a strip or two-dimensional format. 25

33. Container stopper means comprising a seal according to any one of claims 1 to 32.

34. Stopper means comprising a stopper cap fitted with a seal according to any one of claims 1 to 32, said container optionally being a bottle intended to contain, as a food product, an alcoholic drink, optionally wine. 30

35. Stopper means according to claim 34 wherein said stopper cap comprises an optionally threaded plastic material insert, said seal being anchored to said insert, and an outer shell of metal, optionally of Al or Sn, or metallised plastic, or plastic.

36. Use of a seal according to any one of claims 1 to 32 in a container stopper means. -31

37. Use according to claim 36 wherein said container is a bottle intended to contain an alcoholic drink, optionally wine.

38. Method for manufacturing a seal according to any one of claims 1 to 32 wherein: 5 a) a multi-layer component B/S or, when the seal is according to claims 17 to 32, a multi-layer component I/B/S or, when the seal is according to claims 19 to 32, a multi layer component I/Ad/B/S or, when the seal is according to claims 26 to 32, a multi-layer component B/M' is supplied or formed depending on circumstances, in the form of a strip material BB, 10 b) said layer C or, when the seal is according to claims 19 to 32, said layer C' is formed, optionally by extrusion of said material Mc, forming a strip Be, c) a strip Bj of said multi-layer material is formed by laminating the strip BB to at least one surface of said strip Bc, d) said seals are cut from each strip Bj of said multi-layer material, forming a is skeleton or offcuts which are recycled in said material Mc intended to form said layer C or C', so as to give a low material cost for said seal. Dated 15 March, 2011 Amcor Flexibles Capsules Patent Attorneys for the Applicant/Nominated Person 20 SPRUSON & FERGUSON