Abstract
The concepts herein relate to a closing element (1) for containers for liquids, in particular bottles. The closing element (1) comprises at least a cork sheet (2) having two opposite main faces (2a, 2b) and at least a layer of insulating material (7), impermeable to liquids and to air and/or gases, coupled to the cork sheet (2). The layer of insulating material (7), at least partly covers at least one of said two main faces (2a, 2b). The cork sheet (2) and the layer of insulating material (7) are rolled so as to define the closing element (1) by an alternated winding of the cork sheet (2) and the layer of insulating material (7), and the layer of insulating material (7) and the alternated winding are configured and predisposed to make the closing element (1) impermeable or to liquids and air and/or gases. The mechanical winding is guaranteed by a partial and spotted gluing of the surfaces, usually only at the external end thereof.
Claims
1. A closing element for containers for liquids, comprising: a cork sheet having first and second opposite, principal faces; and an impermeable layer of insulating material disposed on the cork sheet so as to at least partly cover at least one of said two principal faces, the cork sheet and the layer of insulating material being rolled so as to define said closing element by a winding of alternating layers of the cork sheet and the layer of insulating material; wherein the alternating layers of said cork sheet and of said layer of insulating material cooperatively engender an overall impermeability of said closing element.
2. The closing element according to claim 1, wherein the overall impermeability of the closing element is substantially equivalent to an overall impermeability of a like cap made solely of cork; wherein the insulating material is deformable and wherein the layer of insulating material is configured for at least partly filling empty spaces and/or for filling surface discontinuities present in the cork sheet as to provide the overall impermeability; and wherein the insulating material is sprayed, spread, injected, applied in a form of an adhesive sheet, or applied by immersion coating on the cork sheet,
3. The closing element according to claim 1, wherein the impermeable insulating material is capable of preventing liquid penetration therethrough when inserted into a wine bottle of an amount: less than 10 mm after a time interval of 12 months; or less than 5 mm after a time interval of 12 months; or less than 2 mm after a time interval of 12 months; or less than 1 mm after a time interval of 12 months; or less than 10 mm after a time interval of 18 months; or less than 5 mm after a time interval of 12 months]; or less than 3 mm after a time interval of 12 months.
4. The closing element according to claim 1, wherein a first turn of winding comprises the layer of insulating material disposed: only the first principal face of the cork sheet; on at least 10% of the first principal face of the cork sheet; on at least 30% of the first principal face of the cork sheet surface; on at least 50% of the first principal face of the cork sheet; on at least 70% of the first principal face cork sheet; on at least 90% of the first principal face of the cork sheet; or on the entire first principal face of the cork sheet.
5. The closing element according to claim 1, wherein: the layer of insulating material is made on the cork sheet in a form of at least a band of minimum height of which is at least 10%, at least 30%, at least 50%, at least 70%, or at least 90% of a height of the cork sheet or the height of the closing element; wherein said band extends substantially over a whole longitudinal extension of the cork sheet, perpendicularly to the height of the cork sheet or to the height of the closing element; or wherein the layer of insulating material is made on the cork sheet in a form of a plurality of bands a sum total of respective heights of said plurality of bands of which at each point of the longitudinal extension of the cork sheet is at least 10%, at least 30%, at least 50%, at least 70%, or at least 90% of a height of the cork sheet or of the height of the closing element, said bands extending on the same face substantially over a whole longitudinal extension of the cork sheet, perpendicularly at the height of the cork sheet or at the height of the closing element; or wherein the layer of insulating material is made on the cork sheet in a form of at least a band a minimum height of which is at least 10 mm, or at least 20 mm, at least 30 mm, at least 40 mm, or at least 50 mm, said band extending substantially over a whole longitudinal extension of the cork sheet, perpendicularly to a height of the cork sheet or to the height of the closing element; or wherein the layer of insulating material is made on the cork sheet in a form of a plurality of bands a sum of the respective heights of which is at least 10 mm, at least 20 mm, at least 30 mm, at least 40 mm, or at least 50 mm, said bands extending on the same face substantially over a whole longitudinal extension of the cork sheet, perpendicularly to the height of the cork sheet and/or to the height of the closing element.
6. The closing element according to claim 1, wherein the insulating material is an adhesive or is configured to be hot-applied or cold-applied to the cork sheet.
7. The closing element according to claim 1, wherein the insulating material is non-adhesive.
8. The closing element according to claim 1 wherein the closing element further comprises a layer of glue or adhesive material configured for: fixing at least an external terminal part of the winding of the cork sheet; or fixing the winding in a form of a closing element; or attaching the layer of insulating material to the cork sheet.
9. The closing element according to claim 1, wherein the insulating material is selected from the group consisting of: an emulsion of a copolymer; an emulsion of an acrylic copolymer; an emulsion of a vinyl copolymer; an emulsion of an acrylic-vinyl copolymer; a sealant; a surface filler; a film former; an impregnating agent; a hydro-repellent; and an oil-repellent.
10. The closing element according to claim 1, wherein the insulating material is non-toxic for food storage.
11. The closing element according to claim 8, wherein the layer of glue or adhesive material is capable of gluing porous surfaces; is of a synthetic type; is of a hot-melt type; or comprises one or more of white hydrogenated hydrocarbon resin; penta-ester resin from erythritol; ethylene vinyl acetate (EVA) copolymer; naphthenic synthetic oil; pharmaceutical grade saturated hydrocarbon oil; or polybutene.
12. The closing element according to claim 1, wherein the cork sheet has a constant thickness between about 0.3 mm and 5 mm, or between about 0.5 mm and about 5 mm; or wherein the cork sheet has, in at least a portion thereof, a thickness between about 0.3 mm and about 5 mm, or between about 0.5 mm and about 5 mm, the thickness varying in a parallel direction to the longitudinal extension of the cork sheet, perpendicularly to the height of the cork sheet or to the height of the closing element; or wherein the cork sheet has a thickness that is variable in a parallel direction to the longitudinal extension of the cork sheet, perpendicularly to the height of the cork sheet or to the height of the closing element, the thickness being minimum at least at a first end of the cork sheet that defines the centre of the winding; or at least at a second end of the cork sheet that defines an external layer of the winding, wherein the thickness is maximum at a portion of the sheet distanced from the ends of the sheet that defines a central portion and an external layer of the winding.
13. The closing element according claim 1, having a diameter between about 15 mm and about 40 mm; between about 18 mm and about 36 mm; or between about 22 mm and about 34 mm; or having a height between about 20 mm and about 70 mm, between about 30 mm and about 70 mm or between about 40 mm and about 60 mm.
14. The closing element according to claim 1, wherein the cork sheet is made of a solid natural cork, an agglomerated cork or micro-agglomerated cork or an insulating material; or wherein the cork sheet comprises a type of cork selected from the group consisting of: natural cork, agglomerated cork and micro-agglomerated cork; or wherein a first portion of the cork sheet comprises agglomerated or micro-agglomerated cork and a second portion of the cork sheet being attached to the first portion comprises solid natural cork; or wherein a first portion of the cork sheet defining a central portion of the closing element comprises agglomerated or micro-agglomerated cork, and wherein a second portion of the cork sheet defining an external layer of the winding is made of solid natural cork.
15. A process for making a closing element for bottles, comprising: providing a cork sheet having two opposite, principal faces; providing a bilayer by applying an impermeable layer of insulating material to the cork sheet so as to at least partly cover at least one of said two principal faces of the cork sheet; and rolling the bilayer so as to provide alternating layers of the cork and the insulating material layers; wherein the insulating material and the cork sheet are configured to make the closing element impermeable to liquids and gases.
16. The closing element of claim 1, wherein said container is a bottle.
17. The closing element of claim 1, wherein said insulating material is impermeable to liquids.
18. The closing element of claim 1, wherein said insulating material is impermeable to gasses and mixtures of different gasses.
19. The closing element of claim 1, wherein said overall impermeability of said closing element is an impermeability to liquids.
20. The closing element of claim 1, wherein said overall impermeability of said closing element is an impermeability to gasses or mixtures of different gasses.
Description
[0025] In an aspect, applying a layer of insulating material comprises spraying, atomising or spreading or applying the insulating material in the form of an adhesive sheet or applying by immersion coating. In an aspect, the process comprises cutting the rolled cork sheet for obtaining a plurality of caps. In an aspect, the cork sheet has a longitudinal extension comprised between 20 mm and 100 mm so as to obtain a single closing element by rolling of the cork sheet, or comprised between 20 mm and 10 m, so as to obtain, by cutting the wound roll of cork, a plurality of caps. In an aspect, the process comprises applying a layer of insulating material on both faces of the cork sheet. There now follows, by way of non-limiting example, a detailed description of one or more preferred embodiments of the concepts herein, in which:
[0026] FIG. 1 illustrates a cork sheet to which a layer of insulating material is applied;
[0027] FIG. 2 illustrates a closing element according to an embodiment of the concepts herein obtained by rolling the cork sheet and the layer of insulating material of FIG. 1;
[0028] FIGS. 3 and 4 illustrate a cork sheet to which a layer of insulating material and a layer of glue are applied;
[0029] FIGS. 5a, 5b, 5c and 5d illustrate cork sheets having a different progression of the thickness along the longitudinal direction of the cork sheet;
[0030] FIGS. 6a and 6b illustrate caps having different cross sections;
[0031] FIG. 7 illustrates a closing element according to an embodiment of the concepts herein;
[0032] FIG. 8 illustrates a cork sheet to which a layer of insulating material is applied with or without glue, another layer of cork and another layer of insulating material;
[0033] FIG. 9 illustrates a cork sheet rolled starting from which a plurality of caps can be made;
[0034] FIGS. 10a and 10b illustrate a cork sheet comprising a first and a second portion in different types of cork;
[0035] FIG. 11 illustrates a closing element according to an embodiment of the concepts herein obtained starting from a cork sheet such as the one illustrated in FIG. 10b,
[0036] FIG. 12 illustrates a graph relative to comparative tests carried out between the solution of EP2136976 and a solution according to the present application;
[0037] FIG. 13 illustrates a further variant embodiment.
[0038] With reference to the figures, 1 denotes in its entirety a closing element. The closing element 1 can be constituted by a cap. The closing element is destined to be used for closing containers in general and in particular bottles containing alcoholic substances, but not only. The closing element 1 is particularly suitable for closing bottles of wine, both still and sparkling. The closing element 1 is made by winding one or more cork sheets 2 on themselves to form a roll having a substantially cylindrical conformation (see FIG. 2). The cork sheet 2 has two main faces 2a, 2b opposite one another and extends mainly in a longitudinal direction between a first and a second end 3, 4. The sheet 2 is generally made of natural cork; according to a variant it can be made of agglomerated or micro-agglomerated cork or another organic or inorganic material. According to a variant, the cork sheet 2 comprises various types of cork, for example both agglomerated cork and natural cork, of both superior and inferior quality. As illustrated in FIGS. 10a and 10b, the cork sheet 2 can have a first portion 6 made of agglomerated cork or micro-agglomerated cork, but not only, and a second portion 5 made of natural cork. Both the portions 5, 6 can extend over a longitudinal semi-extension of the cork sheet 2 (FIG. 10a) so as to constitute two parts of the cork sheet 2, the extension of which can be different according to needs and the characteristics of the specific cap. For example, the two portions can be identical, or alternatively, the first portion 6 of the cork sheet 2 can have a longitudinal extension that is smaller than the longitudinal extension of the second portion 5 of the cork sheet (see FIG. 10b). In general, the first portion 6 can be made of a lower quality of cork or in any case having an exterior aspect that is less pleasing than that of the second portion 5. The cork sheet 2 is rolled so that the first portion 6 constitutes an internal portion of the winding of the closing element 1, while the second portion 5 constitutes an external portion of the winding of the closing element 1 (see FIG. 11). In this way, the closing element 1 has a pleasant exterior aspect while not being all made with the same type of cork, with clear savings on production costs. It should be noted that, in general, the cork considered to be less aesthetically pleasing still has, however, excellent and comparable technical qualities (impermeability, elasticity, etc.). The cork sheet 2 has a height H2, defined perpendicularly to the longitudinal extension L2 thereof, which can be comprised between 20 mm and 70 mm or between 30 mm and 70 mm or between 40 mm and 60 mm. Following the rolling of the cork sheet 2, the height H2 of the sheet, taking account of the winding pressure, substantially defines the height of the closing element 1. The cork sheet 2 further has a thickness S2 comprised between 0.3 mm and 3.5 mm or between 0.3 mm and 3 mm. The modest dimensions of the thickness S2 of the cork sheet 2 facilitate the rolling operation of the sheet 2 to define the closing element 1. As illustrated in FIGS. 1, 3 and 4, the cork sheet 2 can have a thickness S2 that is constant along the whole longitudinal extension L2 thereof. Alternatively, the cork sheet 2 can have a thickness S2 variable between 0.3 mm and 3.5 mm or between 0.3 mm and 3 mm at least at an end 3, 4 thereof. The variation of the thickness S2 at an end 3, 4 of the cork sheet 2 advantageously facilitates the rolling of the sheet 2. The thickness S2 of the cork sheet 2 can vary at only one end 3 (see FIG. 5a) or at both ends 3, 4 (see FIGS. 5b and 5d). In the latter variant, proceeding along the longitudinal extension L2 of the cork sheet 2, the thickness S2 varies at the first end 3 from a minimum thickness (for example 0.5 mm) to a maximum thickness (for example 3 mm), is maintained constant for a central portion of the cork sheet 2 and varies again at the second end 4, reducing from the maximum thickness to the minimum thickness. According to a further variant, the thickness can vary over the whole longitudinal extension L2 of the cork sheet 2 (see FIG. 5c). The thickness S2 can vary linearly or not and continuously or not between the minimum thickness and the maximum thickness depending on the application, the material and the sheet, the container and the liquid to be contained. The use of greater thicknesses enables using shorter sheets (length L2), thus enabling using and appreciating high-quality products which at present are thrown away or granulated for the building industry or for agglomerated and/or granulated caps. According to further variants, it is possible to combine the teachings of the solutions of figures from 5a to 5d with the teachings of FIGS. 10a and 10b. For example according to further variants two or more portions can be included, among which a first portion made of a first type of cork (for example agglomerated or micro-agglomerated cork) and a second portion made of a different (or identical) type of cork (for example natural cork), wherein the first (or vice versa the second portion) further has a variable thickness and the second portion (or vice versa the first portion) has a uniform thickness or a variable thickness in a different measure (as illustrated in figures from 5a to 5d). Further, the variation in thickness can take place in one or more directions.
[0039] The use of greater thicknesses also reduces the quantity of insulator and/or glue required, bringing further benefits, both financial and in terms of production. As illustrated in FIG. 1, a layer of insulating material 7 is applied to the cork sheet 2. Laboratory testing has demonstrated that the layer of insulating material 7 substantially improves the closing element 1 in terms of impermeability over time against gases and/or air and liquids, such as, in particular, but not only, alcoholic solutions. The layer of insulating material 7 further functions as a barrier for oxygen, preventing it from passing through the closing element 1 and therefore entering into contact with the liquid contained in the bottle, preventing or controlling, if appropriately dimensioned, the oxidation of the liquid. In this way, the closing element 1 prevents deterioration of the liquid contained in the bottle. The insulating material is deformable so as to fill the empty spaces, the porosities and the surface discontinuities of the sheet. The deformation of the insulating material can take place during the rolling of the sheet 2, with the rolling pressure action. According to a variant, the deformation can take place before the pressured rolling of the layer of insulating material 7 on the cork sheet 2, for example by a press. By filling the surface irregularities of the sheet and/or imprecisions in the rolling process, the insulating material fills in the empty spaces in the cork so as to prevent formation of pathways for passage of gases and liquids between consecutive layers of cork in the winding. The insulating material can be of an adhesive type, but not only, and can be hot- or cold-applied. The adhesive insulating material guarantees excellent sealing of the closing element 1 and the compactness of the winding which does not deteriorate and does not tend to fail over time. Further, it substantially improves the seal on the pressurised bottling, ensuring the compactness of the external rings in contact with the container and avoiding peeling during the bottling operation.
[0040] In the present description, the term insulating material is intended to mean a material having relevant technical characteristics of impermeability to liquids and air and/or gases, able to guarantee a seal of the closing element to those substances that is sufficiently good for a sufficient time, according to the aims of the concepts herein.
[0041] In the present description, the term substantially impermeable to liquids and air and/or the gases is intended to mean that the element in question substantially prevents the passage of liquids and air and/or gases or which strongly limits the passage so as to guarantee a sufficient seal for the applications of interest, in particular for the closing of wine bottles and/or in a substantially like or similar manner to the degree of impermeability of a single-piece cork cap.
[0042] In a variant, the adhesive insulating material can for example be constituted by a glue having properties of impermeability to liquids and air and/or gases and suitable to be used with the cork. According to another variant, the insulating material can instead be of a non-adhesive type. In this case, to guarantee in any case the blocking of the winding of the cork sheet 2 a layer of glue 8 or any other adhesive material can be applied at least at an end 3, 4 (see FIG. 3) of the cork sheet 2; alternatively the blocking could be mechanical (sewing or the like). Alternatively the layer of glue 8 can be applied on an end portion of the layer of insulating material 7 or on the whole surface of the layer of insulating material 7 (see FIG. 4). The insulating material can be applied in various ways to the cork sheet 2. The insulating material can for example be sprayed or atomised on at least a portion of a face 2a, 2b of the cork sheet 2, or on both the faces 2a, 2b of the cork sheet 2. Alternatively, the insulating material can be spread on the cork sheet 2 or applied in the form of an adhesive sheet. It should be noted that an adhesive material or glue is destined to prevent the separation of two surfaces, while an insulating material ensures the impermeability and the impossibility of penetration between the surfaces. An insulator is not necessarily also an adhesive, and vice versa. According to a further alternative, the cork sheet 2 can be immersed in a bath of liquid insulating material; the immersion in the bath can be partial or complete. Alternatively the insulating material can be injected from the ends after the rolling. Obviously also further application modes of the insulating material can be adopted, as a function of the chemical-physical characteristics and the state (solid or liquid) of the insulating material. The insulating material can be applied several times to the cork sheet 2 so as to reach the desired thickness. Regardless of the application mode of the insulating material to the cork sheet 2, the insulating material is applied on at least a face 2a, 2b of the cork sheet 2 on at least 10% or at least 30% or on at least 50% or at least 70% or at least 90% of the surface of the face 2a, 2b or on the whole surface of the face 2a, 2b. The Applicant has found that optimal impermeability results against the gases and/or the air and the liquids have been obtained by applying the insulating material on at least 50% of the surface of a face 2a, 2b of the cork sheet 2. According to an embodiment, the insulating material is applied on both faces 2a, 2b of the cork sheet 2 on at least 10% or at least 30% or at least 50% or at least 70% or at least 90% of the surface of each face 2a, 2b. A further cork sheet 2 can further be applied on the cork sheet 2, at a face 2a, 2b thereof treated with the insulating material so that a layer of insulating material 7 is interposed between two cork sheets 2. As previously mentioned, the use of greater thicknesses, in this case a plurality of sheets, enables using and appreciating high-quality products which at present are thrown away or granulated for the building industry or for agglomerated and/or granulated caps. The layer of insulating material 7 can extend along a band having a height that is at least equal to 10% or at least 30% or at least 50% or at least 70% or at least 90% of the height H2 of the cork sheet 2. The height of the band can further vary or be constant along the longitudinal extension of the cork sheet 2. The band preferably develops without interruption along the whole longitudinal extension L2 of the cork sheet 2. Alternatively, the insulating material can extend along a plurality of bands each having a respective height and arranged on the same face 2a, 2b of the cork sheet 2. Alternatively the insulating material can be spread or applied in another way suitable for the aim and/or can be applied according to various inclinations and/or applied in the form of a net. The sum of the heights of the bands can be at least equal to 10% or at least equal to 30% or at least equal to 50% or at least equal to 70% or at least equal to 90% of the height H2 of the cork sheet 2. The height of the band, or the sum of the height of the bands, can preferably be at least equal to 10 mm or at least equal to 20 mm or at least equal to 30 mm or at least equal to 40 mm or at least equal to 50 mm and in particular can be substantially equal to the height H2 of the cork sheet 2. As illustrated in FIG. 1, the layer of insulating material 7 can extend substantially over all the surface of a face 2a, 2b of the cork sheet 2, i.e. over the whole height H2 and the whole longitudinal extension L2 of the sheet 2. The winding of the cork sheet 2 and the layer of insulating material 7 defining the closing element 1 can have a substantially spiral progression defined on transversal sections at the height of the closing element (see FIG. 2 and FIG. 6a). Alternatively the cork sheet 2 can be folded to define a conformation such as the one illustrated in FIG. 6b, but not only. The cork sheet 2 can be rolled in such a way that a central core 9 of the winding is orientated in an opposite direction with respect to the main winding direction of the spiral or be folded to form an S shape, i.e. to form a fold having an opposite folding direction with respect to the folding direction of the remaining folds (FIG. 6b). According to a variant, the central core 9 of the closing element 1 can be made of a plastic material, or any organic compound in the olefin class and the cork sheet 2 can be engaged to the central core 9 by a layer of glue 8 (see FIG. 7). In the following the main steps of the process for manufacturing the closing element will be described. In a first step of the process a cork sheet 2 is predisposed. The cork sheet 2 has one or more of the above-described characteristics and can further have a transversal extension L2 comprised between 20 mm and 10 m. Should the closing element have a longitudinal extension H2 comprised between 20 mm and 70 mm, the process is preferably destined for making a single closing element 1, while in a case where the sheet has a longitudinal extension H2 comprised between 20 mm and 10 m, the process is destined to make a plurality of caps 1. FIG. 9 illustrates for example a cork sheet 2 having large dimensions that can be wound and then cut for making a plurality of caps 1. A layer of insulating material 7 is applied to the cork sheet 2 according to the ways described in the foregoing. In the embodiment in which the insulating material is not adhesive, a layer of glue 8 or any other adhesive material can be applied on the layer of insulating material 7 or directly on a face 2a, 2b of the cork sheet 2 as described in the foregoing or on both faces. At this point the cork sheet 2 and the layer of insulating material 7 are rolled so as to define an alternated winding of cork sheets 2 and layers of insulating material 7 (see FIG. 2). The rolling pressure of the cork sheet 2 determines the deformation of the insulating material which, as is becomes modelled, fills the surface irregularities of the cork sheet 2 so as to substantially improve the impermeabilising capacity of the closing element 1 to the gases and liquids. After having rolled the cork sheet 2 together with the layer of insulating material 7, if the sheet 2 has appropriate dimensions as described in the foregoing, the winding can be cut to make a plurality of caps 1. The concepts herein make it possible to obtain one or more of the following advantages and to resolve one or more of the problems encountered in the prior art. Firstly the concepts herein enable conserving liquids (such as wine) in bottles in a better way and for long period of times. The concepts herein further enable making a resistant closing element, which is not subject to structural failure (peeling, but not only) and which improves its characteristics of being impermeable to gases and liquids over time. The concepts herein further enable preventing contact between the air and in particular the oxygen and the liquid contained in the bottle, in this way preventing the deterioration of the liquid (oxidation but not only). The concepts herein further enable making high-quality caps by the use of even very short cork sheets but having a great thickness, and at present considered less valuable and expensive with respect to the sheets of a suitable thickness for making caps in a single piece, and even by the use of cork sheets and parts which are normally considered waste products, thus reprising this important natural product. The concepts herein further enable eliminating or reducing, thanks to the conformation of the closing element and the layer of coating of insulating material that also functions as a stabiliser, the emission of red powders and other possible contaminants (TCA, but not only) from the closing element toward the product contained in the bottle. The concepts herein further enable avoiding or reducing the use of conventional glues and adhesive materials potentially containing contaminant substances. The concepts herein further make available a process which enables making cork caps simple and at low cost. The concepts herein are moreover convenient to use, easy to implement and simple and economical to make.
