Closing cap for containers

Abstract

A closing cap (1) for containers (2) comprising: a shell (3), provided with a lateral wall (4) extending around an axis (X) and with a transversal wall (5) positioned at one end of the lateral wall (4), the shell (3) being provided with an inner coupling structure (7) positioned on the inner side of the lateral wall (4) for defining a reversible coupling of the cap (1) to a neck (201) of said container (2); an insert (8) joined to the shell (3) at an inner surface (5a) of said transversal wall (5) facing a supply opening (203) of the neck (201); the insert (8) and the shell (3) are made of cellulose.

Description

[0001] DESCRIPTION

[0002] CLOSING CAP FOR CONTAINERS

[0003] Technical field

[0004] This invention relates to a closing cap for containers.

[0005] In more detail, this invention relates to a closing cap for containers, which comprises an outer body and a fluid-tight sealing element configured to make a mechanical seal with the neck of a respective container.

[0006] Background art

[0007] As is known, containers such as bottles intended to contain liquid products, at the top have a neck which defines the liquid product outfeed section.

[0008] The neck is usually tapered relative to the liquid product containment zone and has a substantially tubular shape, which extends around an axis and has an upper edge defining the supply opening for the material contained in the container.

[0009] The neck comprises an outer coupling structure which allows a reversible coupling to a respective closing cap, also provided with an inner coupling structure configured to couple to the outer coupling structure of the neck.

[0010] That outer coupling structure may be made in the form of a thread structure, to allow reversible coupling of the cap by screwing the cap onto / unscrewing it from the neck.

[0011] There are also other prior art coupling solutions, for example consisting of undercuts for press-on locking of the cap on the neck.

[0012] Prior art caps consist of a cup-shaped body provided with a transversal wall and with a lateral wall extending around a longitudinal axis of extension of the neck.

[0013] The caps are also provided with a projection shaped like a sealing lip, with annular shape (usually called a plug), which projects from the transversal wall towards the inside of the cap. In this situation, in the cap closed condition, the projection abuts against an inner or outer wall of the neck at the supply opening of the neck to make a mechanical seal.

[0014] In other words, the annular projection abuts against the wall of the neck in order to apply a contact pressure against that wall, therefore preventing the passage of the liquid product.

[0015] The prior art caps described above are mainly made of PE (Polyethylene) whilst the respective containers are widely made of PET (Polyethylene Terephthalate).

[0016] However, in this situation carrying out recycling procedures is difficult due to the different materials used.

[0017] In order to facilitate those recycling processes, caps may be made of the same material, PET, as that used to make the container. In fact, PET is 100% recyclable and does not lose its fundamental properties during the recycling process, meaning that it can be repeatedly processed in order to make new bottles or other objects.

[0018] However, PET caps have considerable functional disadvantages derived from the material which, sliding on the PET neck, generates a high level of friction which opposes rotation of the cap relative to the neck during screwing / unscrewing. Even the cap sealing projection creates a high level of friction on the surface of the neck.

[0019] Considering the above, the consumer during the step of uncoupling / coupling the PET cap from / to a container neck, must apply a very high removing, or applying torque in order to be able to overcome the friction between the cap and the neck. In fact, the force necessary to uncouple the outer coupling structure of the neck from the inner coupling structure of the cap, for example to unscrew it, must be added to the force necessary to uncouple the cap sealing protrusion.

[0020] Moreover, the friction between the cap sealing protrusion and the neck inner / outer wall may cause the contact surfaces between the cap and the neck to deteriorate, causing wear on them. In addition to the above, it should however be noticed that the use of plastic (PE or PET) has various environmental disadvantages since, if the cap is not appropriately recycled, it significantly contributes to marine and land pollution. Since the plastic is not biodegradable, the caps may remain in the environment for centuries, fragmenting into microplastics which are harmful to ecosystems.

[0021] To overcome this disadvantage there are also prior art caps in which the outer shell is made of natural fibre-based material, such as in particular cellulose, but which internally comprises a sealing element (plug) in any case made of plastic.

[0022] For this reason, the cap is made in two pieces, with the plug separate and made of plastic which is subsequently glued inside the shell.

[0023] However, even this solution is not capable of solving the disadvantage derived from the use of plastic, precisely due to the necessary presence of the plug.

[0024] Disclosure of the invention

[0025] The technical purpose of this invention is therefore to make available a closing cap for containers which is capable of overcoming the disadvantages which emerged in the prior art.

[0026] In particular, the aim of the invention is therefore to improve the caps for containers, considerably eliminating the presence of plastic but at the same time guaranteeing the fluid-tight seal of the caps on the respective containers.

[0027] Another aim of this invention is to make available a cap made of material with low environmental impact and therefore capable of simplifying cap disposal and recycling processes.

[0028] A further aim is to supply a method for making a cap provided with a fluid- tight sealing element which is easy to obtain and to work using known forming techniques. Another aim of the invention is to supply a closing cap for containers which is capable of making an effective mechanical seal, reducing the possibility that the contact surfaces between cap and neck may deteriorate due to friction.

[0029] The technical purpose indicated and the aims specified are substantially achieved by a closing cap comprising the technical features set out in one or more of the appended claims. The dependent claims correspond to possible embodiments of the invention.

[0030] Brief description of drawings

[0031] The invention can be better understood and implemented with reference to the accompanying drawings, which illustrate several example, non-limiting embodiments of it, in which Figures 1 to 7 show a longitudinal section of a cap according to this invention applied to the neck of a respective container and according to different embodiments of this invention.

[0032] Detailed description of preferred embodiments of the invention

[0033] With reference to the accompanying figures, the numeral 1 denotes a closing cap for a container 2, of which container only a neck 201 is shown. Preferably, the container 2 is a bottle intended to contain a liquid substance such as a drink.

[0034] The cap 1 shown in Figures 1 to 4, corresponding to respective alternative embodiments, is in a closed condition, in which the cap 1 is coupled to the container 2.

[0035] In particular, the cap 1 comprises a shell 3 provided with a lateral wall 4 which extends around an axis “X”, and with a transversal wall 5 positioned at one end of the lateral wall 4, so as to close that end.

[0036] The transversal wall 5 extends perpendicularly to the axis “X” and is preferably, but without limiting the scope of the invention, flat and has a circular periphery. In this situation, the lateral wall 3 is connected to the transversal wall 5 without interruption, by means of a connecting zone 6, which may be shaped, in cross-section, like a rounded edge.

[0037] The shell 3, defined by the lateral wall 4 and by the transversal wall 5, is preferably cup-shaped and is suitable for receiving the neck 201 of the container 2, to allow the cap 1 to close the container 2 (as illustrated in the figures).

[0038] It should be noticed that the neck 201 comprises a body having a substantially tubular shape, which extends around the above-mentioned axis “X” when the cap 1 is coupled to the neck 201 .

[0039] An outer coupling structure 202 is also provided, configured to allow reversible coupling to the respective cap 1 .

[0040] Advantageously, the coupling structure 202 is made in the form of a thread structure which extends on the outer surface of the neck 201 .

[0041] In this situation, the shell 3 is provided with an inner coupling structure 7, positioned on the inner side of the lateral wall 4, which is configured to removably couple the whole cap 1 to the neck 201 of the container 2.

[0042] In this case too, the coupling structure 7 of the lateral wall 4 is made in the form of a thread structure to allow the shell 3 to be screwed onto the neck 201.

[0043] In other words, the passage from the closed condition to the open condition (not illustrated) of the cap 1 , and vice versa, is carried out by a rototranslation movement around the axis “X”, that is to say, rotation of the shell 3 relative to the neck 201 and movement of the shell away from or towards the neck 201 .

[0044] However, it must be specified that the coupling structure 202 of the neck 201 and the coupling structure 7 of the lateral wall 4 may be made in any way suitable for allowing cap 1 mechanical coupling to the neck 201. For example, there may even be press-on locking undercuts for coupling the cap 1 to the neck 201 by moving the cap 1 along a line parallel to the axis “X”. Preferably, the shell 3 is completely made of natural fibre-based material, advantageously cellulose. Therefore, the lateral wall 4 and the transversal wall 5, as well as the coupling structure 7, are made of cellulose.

[0045] However, it should be specified that the shell 3 may be made of another material suitable for the specific use and in compliance with the environmental protection regulations in force.

[0046] The cap 1 also comprises an insert 8 joined to the shell 3 at an inner surface 5a of the transversal wall 5 facing the supply opening 203 of the neck 201 .

[0047] Advantageously, the insert 8 is made of plant fibre-based material, preferably cellulose.

[0048] In this situation, both the shell 3 and the insert 8 of which the cap 1 is composed are advantageously made of cellulose.

[0049] It should also be noticed that the insert 8 and the shell 3 are made in two separate bodies and engaged with each other.

[0050] In particular, the insert 8 comprises a body 9 having a concave shape. In more detail, the body 9 is cup-shaped.

[0051] The body 9 defines a transversal portion 10 anchored to the above- mentioned transversal wall 5 and a lateral portion 11 extending from a peripheral edge of the transversal portion 10.

[0052] In this situation, as illustrated in the figures, the lateral portion 11 extends from the transversal portion 10 and inside the opening 203 of the neck 201.

[0053] According to the embodiments illustrated in Figures 1 to 6, the lateral portion 11 of the insert 8 has a contact wall 12 configured, in the cap closed condition, to engage by making a fluid-tight seal inside the supply opening 203 of the neck 201 .

[0054] The transversal portion 10 has a shape which is substantially transversal to the axis “X” and is disk shaped. As illustrated in the example in Figure 5, the transversal portion 10 may have a circular guide 10a configured to adapt to the inside of a hollow 5b made in the transversal wall 5. In this case, the hollow 5b, also having a circular shape, is a centring zone for facilitating positioning of the insert 8 relative to the shell 3 in the coupling operations.

[0055] Advantageously, any insert 8 positioning errors are eliminated in order to ensure correct positioning and consequently a correct fluid-tight seal on the neck 201 .

[0056] Moreover, according to an embodiment not illustrated, the transversal portion 10 may even have an annular shape and therefore be provided with an inner through cavity. In this case too, there may be an annular groove made on the inner surface 5a of the wall 5 in order to simplify insert 8 positioning.

[0057] As illustrated in the embodiment of Figure 1 the lateral portion 11 is substantially frustoconical, that is to say, divergent moving away from the transversal portion 10.

[0058] In this situation, the contact wall 12 is positioned at an end annular edge 13 of the lateral portion 11 distal from the transversal portion 10. It should be noticed that in the cap 1 closed condition, the annular edge 13 is in contact with an inner cylindrical surface 204 of the neck 201 to guarantee the fluid-tight seal and therefore to prevent the liquid from coming out from the inside of the container 2 and through the supply opening 203.

[0059] In accordance with the embodiments of Figures 2 to 4, the lateral portion 11 is substantially cylindrical.

[0060] In other words, the lateral portion 11 extends away from the transversal portion 10 parallel to the axis “X” and in a substantially constant way.

[0061] In accordance with Figure 2, an inner surface of the lateral wall 11 is divergent moving away from the transversal portion 10. In contrast, Figure 3 and Figure 5 show an embodiment in which the inner surface of the transversal portion 10 is straight, defining a constant width.

[0062] In the embodiments of Figure 2, 3 and 5, the contact wall 12 extends at an annular surface 14 of the lateral portion 11 in contact with the above- mentioned inner surface 204 of the neck 201 . In this case, advantageously the annular surface 14 which defines the fluid-tight seal is parallel to the inner surface 204.

[0063] Furthermore, in the embodiment of Figure 4 the lateral portion 11 is again substantially cylindrical, but is spaced apart from the inner surface 204 of the neck 201 .

[0064] In this case, an annular projection 15 is provided extending on the outside from an end edge of the lateral portion 11 distal from the transversal portion 10. Advantageously, an annular surface 14 of the annular projection 15 is in contact with the inner surface 204 of the neck 201 for defining the above-mentioned fluid-tight seal.

[0065] It should be noticed that in all of the embodiments described above the transversal portion 10 may also be made with an annular shape. However, it is simpler to make a disk-shaped configuration, rather than the annular one, in the respective steps for obtaining the insert 8.

[0066] Advantageously, in accordance with an embodiment not illustrated in the accompanying figures, the body 9 may have two lateral portions 11 which are parallel and concentric. The lateral portions are spaced apart from each other for receiving the neck 201 of the container 2. In this situation, each wall 11 applies a mechanical sealing action respectively on the inner surface 204 of the neck 201 and on a respective outer surface of the neck 201. That double seal, created by the two portions 11 placed “straddling” the neck 201 , therefore guarantees an improved fluid-tight seal of the cap 1 on the neck 201 .

[0067] Moreover, it should be noticed that in all of the embodiments described above and illustrated in Figures 1 to 6, the lateral portion 10 defines, in cooperation with the transversal portion 11 , a containment space 16 for a liquid product.

[0068] In other words, the insert 8 may also have the function of “doser” of the liquid product contained in the bottle 2, given the particular concave shape of the body 9.

[0069] Advantageously, in accordance with an embodiment not illustrated, the lateral wall 11 of the body 9 may protrude more (extend further towards the inside of the container 2) and be spaced apart from the neck 201 in order to only perform the function of “doser” of the liquid product. In this case, the mechanical sealing action is performed by other zones of the shell 3.

[0070] Preferably, in accordance with the embodiments of Figures 1 to 5, the transversal portion 10 of the body 9 may be coupled by gluing to the inner surface 5a of the transversal wall 5 of the shell 3. In this case, the coupling between the shell and the insert 8 is stable and fixed.

[0071] Alternatively, the transversal portion 10 of the concave body 9 may be coupled by mechanical interference to the inner surface 5a of the transversal wall 5 of the shell 3.

[0072] In this case, it is possible to obtain a stable constraint or a “floating” constraint which therefore leaves play between the shell 3 and the insert 8.

[0073] Advantageously, that play allows the insert 8 to be kept in position in the first steps of opening the cap 1 in which the shell 3 begins to rotate around the neck 201. In other words, the shell 3 and the insert 8 are movable relative to each other within a predetermined angular path defined by the rotation of the cap 1 on the neck 201 .

[0074] In this way a predetermined fluid-tight seal is advantageously guaranteed by the insert 8 not just in the cap 1 completely closed condition, but also in an intermediate condition in which the cap 1 is partially unscrewed from the neck 201 .

[0075] With reference to Figure 6, an embodiment is illustrated in which the body 9 is upside down compared with the embodiments of Figures 1 to 5. In this case, the portion 10 is spaced apart from the transversal wall 5 whilst the free end of the lateral portion 11 is coupled to the transversal wall 5. In other words, in the embodiment of Figure 6 the coupling of the insert 8 to the shell 3 is carried out by constraining, mechanically or by gluing, the circular end of the portion 11 to the inner surface 5a. It should be noticed that the mechanical sealing functions performed by the portion 11 and in particular by the contact wall 12 remains identical to what is described above for the embodiments of Figures 1 to 5. In fact, in this case too, the contact surface 14, in the cap closed condition, remains in contact with the inner surface 204 of the neck 201 .

[0076] In accordance with the solution in Figure 7, the body 9 is obtained starting from a flat web made of cellulose. In this case the lateral portion 11 is obtained by folding a circular stretch of the flat web. Moreover, in this solution the body 9 comprises a peripheral edge 17 which extends on the outside of the portion 11 . As illustrated, the peripheral edge 17 is coplanar with the portion 10 and defines a surface for contact with the edge of the neck 201 .

[0077] This invention also relates to a method for making the cap 1 , which comprises the steps of moulding a shell 3 provided with a lateral wall 4 extending around an axis X and with a transversal wall 5 positioned at one end of the lateral wall 3. Moulding of the shell 3 also produces an inner coupling structure 7 positioned on the inner side of the lateral wall 4 for defining a reversible coupling of the cap 1 to the neck 201 of the container 2. The method also comprises the step of moulding an insert 8 configured to be joined to the inside of the shell 3.

[0078] The step of moulding an insert 8 is advantageously carried out by compressing a material made of cellulose.

[0079] The step of moulding the shell 3 may also advantageously be carried out by compressing a material made of cellulose in order to obtain a whole cap 1 made of completely biodegradable material.

[0080] The step of moulding the insert 8 is also carried out by making a concave, preferably cup-shaped body 9 defining a transversal portion 10 and a lateral portion 11 extending from the peripheral edge of the transversal portion 10 and inside the opening 203 of the neck 201 .

[0081] The method also comprises the step of joining the insert 8 to the shell 3 at an inner surface 5a of the transversal wall 5 facing the opening 203 of the neck 201 .

[0082] Advantageously, the step of joining the insert 8 to the shell 3 is carried out by engaging the transversal portion 10 with the transversal wall 5.

[0083] According to a first possible embodiment, the transversal portion 10 of the body 9 is coupled by mechanical interference to the inner surface 5a of the transversal wall 5 of the shell 3. That coupling may define a stable constraint between insert 8 and shell 3 or a “floating” coupling in which the insert 8 and the shell 3 are movable relative to each other within a predetermined angular path defined by the rotation of the shell 3 on the neck 201 .

[0084] Alternatively, according to a further embodiment, the transversal portion 10 of the body 9 is coupled by gluing to the inner surface 5a of the transversal wall 5. Therefore, the gluing defines a rigid constraint between shell 3 and insert 8.

[0085] The invention described above therefore solves the disadvantages of the prior art and brings many advantages.

[0086] First, making two separate elements, shell 3 and insert 8, allows the use of a degradable material such as in particular cellulose. In this way the presence of plastic is advantageously eliminated from every component of the cap 1 .

[0087] In addition, the possibility of making the insert 8 as a body separate from the shell 3 allows treatment of only the insert 8, subjecting it to any specific treatments necessary.

[0088] For example, only the insert 8 may be coated with a barrier layer for separating the cellulose material from the liquid product contained in the container 2. Moreover, the insert 8 may be formed and treated to obtain a specific sturdiness / elasticity in response to the mechanical stresses to which it is subjected in its mechanical sealing function.

[0089] The insert 8 may also be modified in terms of its shape and size so as to adapt it to the structure of the neck 201 of the container 2 and to the various mechanical sealing needs. That versatility allows the shape of the shell 3 to be kept constant and only the insert 8 to be modified with the consequent advantages in terms of simplicity making it and therefore production costs of the whole cap 1 .

[0090] Finally, it should be noticed that the method for making the cap 1 is particularly simple given the moulding of the two elements, shell 3 and insert 8, which have very simple shapes unlike the prior art caps in a single body which in contrast are complex to make in the moulding steps.

Claims

CLAIMS1 . Closing cap for containers comprising:- a shell (3), provided with a lateral wall (4) extending around an axis (X) and with a transversal wall (5) positioned at one end of the lateral wall (4), the shell (3) being provided with an inner coupling structure (7) positioned on the inner side of the lateral wall (4) for defining a reversible coupling of the cap (1 ) to a neck (201 ) of said container (2);- an insert (8) joined to the shell (3) at an inner surface (5a) of said transversal wall (5) facing a supply opening (203) of the neck (201 ); wherein said insert (8) is made of cellulose and wherein the insert (8) has a body (9) having a concave shape.

2. Cap according to any of the preceding claims, wherein the insert (8) and the shell (3) are made in two separate bodies and engaged with each other.

3. Cap according to any of the preceding claims, wherein the body (9) is cup-shaped and defines a transversal portion (10) anchored to said transversal wall (5) and a lateral portion (11 ) extending from a peripheral edge of said transversal portion (10) and inside the opening (203) of the neck (201 ) in the cap (1 ) closed condition.

4. Cap according to the preceding claim, wherein the lateral portion (11 ) of said insert (8) has a contact wall (12) configured, in a cap (1 ) closed condition, to engage by making a fluid-tight seal in the supply opening (203) of the neck (201 ).

5. Cap according to claim 3, wherein the lateral portion (11 ) of said insert (8) defines, in cooperation with the transversal portion (10), a containment space (16) for a liquid product.

6. Cap according to claim 3, wherein said transversal portion (10) of the body (9) is coupled by mechanical interference and / or by gluing to said inner surface (5a) of the transversal wall (5) of the shell (3).

7. Cap according to any of claims 3 to 6, wherein the transversal portion (10) is disk shaped and wherein the lateral portion (11 ) is frustoconical.

8. Cap according to the preceding claim when it depends on claim 4, wherein said contact wall (12) extends at an end annular edge (13) of said lateral portion (11 ) distal from said transversal portion (10); said annular edge (13) in the cap (1 ) closed condition being in contact with an inner surface (204) of the neck (201 ).

9. Cap according to any of claims 3 to 6, wherein the transversal portion (10) is disk shaped or annular and wherein the lateral portion (11 ) is cylindrical.

10. Cap according to the preceding claim when it depends on claim 4, wherein said contact wall (12) extends at an annular surface (14) of said lateral portion (11 ) in contact with an inner surface (204) of the neck (201 ) in the cap (1 ) closed condition.

11. Cap according to the preceding claim, wherein said annular surface (14) is defined by an annular projection (14) of said lateral portion (11 ) in contact with the inner surface (204) of the neck (201 ).

12. Cap according to any of the preceding claims, wherein the shell (3) is made of cellulose.

13. Method for making a closing cap for containers, wherein it comprises the steps of:- moulding a shell (3) provided with a lateral wall (4) extending around an axis (X) and with a transversal wall (5) positioned at one end of the lateral wall (4), the shell (3) being provided with a coupling structure (7) positioned on the inner side of the lateral wall (4) for defining a reversible coupling of the cap (1 ) to a neck (201 ) of said container (2);- moulding an insert (8) configured to be joined to the inside of the shell (3); characterised in that said step of moulding the insert (8) is carried out by compressing a cellulose material to obtain a concave body (9).

14. Method according to the preceding claim, wherein it also comprises the step of joining said insert (8) to the shell (3) at an inner surface (5a) of said transversal wall (5) of the shell (3) facing a supply opening (203) ofthe neck (201 ).

15. Method according to the preceding claim, wherein said step of moulding the insert (8) is carried out by making the concave body (9) defining a transversal portion (10) and a lateral portion (11 ) extending from a peripheral edge of said transversal portion (10) and inside the opening (203) of the neck (201 ) in the cap (2) closed condition; said transversal portion (10) being engaged with the transversal wall (5) during said step of joining the insert (8) to the shell (3).

16. Cap according to the preceding claim, wherein said transversal portion (10) of the body (9) is coupled by mechanical interference and / or by gluing to said inner surface (5a) of the transversal wall (5) of the shell (3).

17. Cap according to any of claims 13 to 16, wherein said step of moulding the shell (3) is carried out by compressing a material made of cellulose.

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