A tamper-evident ring for a closure for a container, and a closure for a container
The tamper-evident ring with optimized stiffness and deformability provides reliable evidence of first opening by preventing separation and plastic deformation, addressing issues in existing designs.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- GUALA CLOSURES SPA
- Filing Date
- 2026-01-14
- Publication Date
- 2026-07-30
AI Technical Summary
Existing tamper-evident rings in closures often fail to provide reliable evidence of opening due to excessive stiffness, leading to false indications or separation from the container neck, while reducing thickness leads to false evidence of opening.
A tamper-evident ring design with optimized stiffness and elastic deformability, featuring an inclined outer surface on the lower part to ensure retention on the container neck and provide clear evidence of first opening.
The design enhances the success rate of maintaining the tamper-evident function by preventing plastic deformation during application and ensuring visible evidence of initial opening.
Smart Images
Figure EP2026050766_30072026_PF_FP_ABST
Abstract
Description
[0001] TITLE: “A tamper-evident ring for a closure for a container, and a closure for a container”.
[0002] DESCRIPTION FIELD OF INVENTION
[0003] The present invention relates to a tamper-evident ring for a closure for closing the mouth of a container, and specifically a tamper-evident ring for a drawn metal cap for a bottle for containing liquids.
[0004] Description of Prior Art
[0005] Closures for containers with tamper-evident rings are known in the prior art. In more detail, the known closures comprise a cap, for example a drawn metal cap, as an aluminium cap, which engages with the thread of the neck of the container, e.g., a glass bottle, and a polymeric insert interposed between the mouth of the container and the cap to ensure the sealing of the container. The known closures also comprise a tamper-evident ring in order to provide the final consumer with a guarantee that such bottles have not been tampered with after bottling.
[0006] Specifically, the tamper-evident ring engages the respective cap during the normal operation of the closure, and it is separated from the cap when the closure is opened for the first time. The known tamper-evident rings have a first upper ring which is inserted into a seat formed in the cap, and a lower part that retains the tamper-evident ring on the neck of the bottle. More specifically, these rings remain in place on the neck of the container when the cap is removed to allow access to the content of the container.
[0007] In order to provide evidence that the bottle has been opened for the first time, the lower part of the tamper-evident ring may be deformed towards the outside of the container, showing that the closure has been opened. The deformation of the ring also ensures that the ring cannot be placed back into the cap to simulate an intact closure.
[0008] An example of a tamper-evident ring is disclosed in US 3812991 A, where thetamper-evident ring is made of metallic material. Another example is shown in DE 3833945 Cl, where the tamper-evident ring is made of polymer material.
[0009] EP1950143 Al shows an example of a tamper-evident ring with a different deformation configuration with respect to the above documents.
[0010] Prior Art Problems
[0011] In known closures, it is often the case that, when the closure is opened, due to an excessive stiffness of the lower part of the tamper-evident ring, there is little or no deformation of the lower part, resulting in the tamper-evident ring being removed from the neck of the container together with the cap. In these cases, the tamper-evident function is clearly compromised, and the closure can be placed back on the container with no evidence of opening.
[0012] In order to overcome this problem, the thickness of the lower part of the known tamper-evident rings has been reduced. However, this led to the opposite problem. Indeed, when the known closures are applied to the containers, the lower part of the tamper-evident ring is subject to deformation or separation from the upper ring, giving false evidence that the closure has been opened.
[0013] SUMMARY OF THE INVENTION
[0014] Therefore, object of the present invention is providing a tamper-evident ring capable of overcoming the aforementioned prior art drawbacks.
[0015] In particular, the object of the present invention is to provide a tamper-evident ring that allows for a more efficient tamper-evident function in closures for containers.
[0016] The technical purpose and object are substantially fulfilled by a tamper-evident ring that comprises the technical features disclosed in one or more of the accompanying claims.
[0017] AdvantagesThe tamper-evident ring of the present invention ensures an optimised ratio between stiffness and elastic deformability between the lower part and the upper ring of the tamper-evident ring, so that when the closure is mounted on the neck of a container, the tamper-evident ring can be stretched in order to pass towards the neck and be effectively retained therein, without being subjected to plastic deformation which could lead to false evidence of opening of the closure.
[0018] Advantageously, the present tamper-evident ring thus allows for a more efficient application of the closure to a container, while at the same time ensuring adequate deformation upon first opening of the closure to provide evidence of the opening of the closure.
[0019] The Applicant has surprisingly found that tamper-evident rings as described in the present invention generally have a lower failure rate, both during application and during opening of the closure, than tamper-evident rings known in the prior art.
[0020] BRIEF DESCRIPTION OF THE FIGURES
[0021] The features and advantages of the present invention will become apparent from the following detailed description of a possible practical embodiment thereof, illustrated by way of non-limiting example in the accompanying drawing, in which:
[0022] - Figure 1 shows a partial cross section of a side view of a closure comprising a cap and a tamper-evident ring according to the present invention;
[0023] - Figure 2 shows a partial cross section of a side view of a closure mounted on a neck of a container and comprising a tamper-evident ring according to the present invention;
[0024] - Figure 3 shows a close-up of a detail of the tamper-evident ring of the present invention;
[0025] - Figure 4 shows a top view of a tamper-evident ring of the present invention.DETAILED DESCRIPTION
[0026] With particular reference to the accompanying figures, 1 refers to a tamper-evident ring for a closure 10 comprising a cap 20 intended to close a mouth 31 of a container, e.g., a glass bottle for containing liquids. In particular, the container (not shown) comprises a threaded neck 30 that terminates into the mouth 31, which has an outer surface 30a and an opposite inner surface 30b, and a plurality of beads 32 defined by thread.
[0027] The tamper-evident ring 1 of the present invention is configured to be mounted on the neck 30 of the container, together with the cap 20 of the closure 10.
[0028] The tamper-evident ring 1 comprises an upper ring 2 configured to engage with an annular seat 21 formed in the cap 20, as shown in Figures 1 and 2 and better detailed hereinafter. The upper ring 2 has a central axis A extending along a longitudinal direction X-X.
[0029] The tamper-evident ring 1 also comprises a lower part 3 which is concentric with the upper ring 2. In other words, the central axis of the lower part 3 corresponds to the central axis A of the upper ring 2.
[0030] According to an aspect, the lower part 3 extends along a lower ring concentric to the upper ring 2 and spaced from the upper ring 2 along the longitudinal direction X.X.
[0031] The lower part 3 comprises a retaining wall 4 configured to engage with the outer surface 30a of the neck 30 to retain the tamper-evident ring 1 on the neck 30 of the container.
[0032] Preferably, the retaining wall 4 has a contact wall 4a configured to engage with a bead 32 of the neck 30 of the container to retain the tamper-evident ring 1 on the neck 30 upon first opening of the closure 10. In more detail, the contact wall 4a is configured to abut against a bottom part of the bead 32 to prevent the removal of the tamper-evidentring 1 from the neck 30 then the cap 20 is removed from the container to allow access to the liquids.
[0033] The lower part 3 also comprises a side wall 5 extending between a first end portion 5a, which is fixed to the upper ring 2, and a second end portion 5b, which is fixed to the retaining wall 4.
[0034] According to the preferred embodiment, the side wall 5 and the retaining wall 4 are made in one piece.
[0035] According to the same embodiment, the lower part 3 is made in one piece with the upper ring 2. In this way, the lower part 3 is configured to remain attached to the upper ring 2 upon first opening of the closure 10. During normal operation of the tamper-evident ring 1, the side wall 5 of the lower part 3 is intended to remain attached to the upper ring 2.
[0036] The side wall 5 of the lower part 3 has an inner surface 6, which is configured to face the outer surface 30a of the neck 30 when the tamper-evident ring 1 is mounted on the neck 30 of the container.
[0037] The side wall 5 also has an outer surface 7, opposite to the inner surface 6, and configured to face outwards from the neck 30 when the tamper-evident ring 1 is mounted on the neck 30 of the container.
[0038] The outer surface 7 is at least partially inclined with respect to the central axis A by an angle of inclination and converges inwardly towards the inner surface 6.
[0039] According to a preferred aspect, the inner surface 6 extends substantially parallel to the central axis A. Consequently, the outer surface 7 is at least partially inclined by the above-mentioned angle of inclination with respect to the inner surface 6.
[0040] The angle of inclination of the outer surface 7 is preferably comprised between 1° and 3°.
[0041] According to a first embodiment, the angle of inclination of the outer surface 7with respect to the central axis A is substantially constant along the longitudinal direction X-X. In other words, the outer surface 7 has a constant slope along the longitudinal direction X-X for its entire length.
[0042] According to a second embodiment, alternative to the first embodiment and shown in Figure 3, the outer surface 7 comprises a first portion 7a and a second portion 7b. The first portion 7a is substantially parallel to the central axis A, and preferably to the inner surface 6, while the second portion 7b is inclined with respect to the central axis A by the above-mentioned angle of inclination. In other words, the outer surface 7 has different slopes along the longitudinal direction X-X.
[0043] Preferably, the first portion 7a is closer to the upper ring 2 than the second portion 7b. Still preferably, the first portion 7a is in correspondence of the first end portion 5a of the side wall 5. Still preferably, the second portion 7b extends from the first end portion 5a of the side wall 5 to the end of the second end portion 5b, and specifically a free end of the side wall 5.
[0044] According to an aspect, shown in Figure 3, the side wall 5 has a first thickness si at the first end portion 5a and a second thickness s2 at the second end portion 5b, where the first and second thicknesses si, s2 are defined between the inner surface 6 and the outer surface 7.
[0045] The second thickness s2 is smaller than the first thickness si. In other words, the side wall 5 is thinner at the second end portion 5b than at the first end portion 5a.
[0046] Preferably, the second thickness s2 is smaller than the first thickness si at least of 50%.
[0047] Advantageously, the difference in thickness between the first and the second end portions 5a, 5b, and specifically the inclination of the outer surface 7, guarantees an optimised stiffness between the lower part 3 and the upper ring 2, thus ensuring that the tamper-evident ring 1 is not subjected to plastic deformation during the application ofthe closure 10 on the neck 30 of the container, while at the same time providing the tamper-evident function during the first opening, as will be better explainer hereinafter.
[0048] In fact, a high stiffness along the entire side wall of the tamper-evident ring 1 could result in the lower part not being subjected to deformation when the closure is opened, thus compromising the tamper-evident function. On the contrary, a low stiffness along the entire side wall 5 could cause the lower part to deform when the closure is applied to the container, thus giving false evidence of the opening of the closure.
[0049] It has been surprisingly found that the inclination of the outer surface 7 of the side wall 5 provides an optimised combination of stiffness and flexibility of the tamper-evident ring 1, which increases the success rate of the closure.
[0050] According to a preferred aspect, the side wall 5 has the shape of a cylindrical section.
[0051] According to the same aspect, the retaining wall 4 projects from the second end portion 5b of the side wall 5 inwardly towards the first end portion 5a. In more detail, the retaining wall 4 is transversal to the side wall 5.
[0052] Preferably, the retaining wall 4 has an upwardly converging frustoconical shape that terminates into the contact wall 4a.
[0053] According to an aspect, the upper ring 2 comprises an inner surface 2a, which is preferably cylindrical, and an opposite outer surface 2b, which is preferably slightly conical, having a diameter greater than a diameter of the inner surface.
[0054] According to the preferred embodiment, shown in Figure 4, the lower part 3 comprises two or more segments 3a shaped as cylindrical sections. Each segment 3a is spaced from the other segments 3a along a circumferential direction.
[0055] Preferably, each segment 3a comprises a respective retaining wall 4 and a respective side wall 5, and the outer surface 7 of the side wall of each segment 3a isinclined with respect to the central axis A.
[0056] It should be noted that all the technical features generically described for the side wall 5 and retaining wall 4 of the lower part 3 are also to be considered as being included for the side wall and retaining wall of each segment 3a.
[0057] According to an embodiment, the side wall 5 of each segment 3a comprises a weakening line configured to fix the side wall 5 to the upper ring 2. The weakening line is configured to be bent outwards and / or to deform plastically upon first opening of the closure, so that each segment 3a is bent, preferably upwardly, towards the outside of the neck 30.
[0058] In this way, the tamper-evident ring 1 provides evidence of first opening. In addition, the bending or plastic deformation of the lower part ensures that the tamper-evident ring 1 cannot be placed back into its original position for tampering operations.
[0059] According to an alternative embodiment, the side wall 5 of each segment 3a is fixed to the upper ring 2 by means of permanent connection members, configured to ensure that the segment 3a is not separated by the upper ring upon first opening of the closure 10. The side wall 5 also comprises temporary connection members, configured to be broken upon first opening of the closure. In this way, only a portion of each segment 3a remains attached to the upper ring 2, while the other portion is detached from the upper ring 2, giving evidence of the opening of the container. In this example, the segments 3a are bent laterally, in clockwise or anticlockwise directions.
[0060] Examples of temporary connection members include weakened lines, scorelines, discontinuous lines forming bridges, bridges with low mechanical strength.
[0061] The above embodiments are only some examples of tamper-evidence functions. It is to be noted that a person skilled in the art will be able to find alternative equivalents to these embodiments.
[0062] According to the preferred aspect, the tamper-evident ring 1 is made of plasticmaterial, for example from a polymer material such as polyethylene, high-density polyethylene, low-density polyethylene, or a mixture of high-density polyethylene and low-density polyethylene.
[0063] Another object of the present invention is a closure 10 for a container. The closure 10 comprises a tamper-evident ring 1 according to the present description.
[0064] The closure 10 also comprises a cap 20 configured to close the mouth 31 of the container. Preferably, the cap 20 is made of drawn metal, more preferably of aluminium.
[0065] Still preferably, the cap 20 has a top wall 20a and a side wall 20b.
[0066] According to the preferred aspect, the side wall 20a of the cap 20 comprises engagement members for engaging the cap 20 to the neck 30 of the container. More preferably, the cap 20 comprises a thread corresponding to the thread of the neck 30 of the container.
[0067] Optionally, the cap 20 comprises an insert at the top wall 20a which is configured to seal the container’s mouth when the closure 10 is mounted thereon.
[0068] The cap 20 comprises an annular seat 21 configured to receive the upper ring 2 of the tamper-evident ring 1 and engage with the upper ring 2. Preferably, the annular seat 21 is a hollow seat formed at the inner surface of the side wall 20b of the cap 20. Still preferably, the annular seat 21 is formed at a bottom free edge portion of the side wall 20b of the cap 20.
[0069] The engagement between the upper ring 2 of the tamper-evident ring 1 and the annular seat 21 of the cap 20 is known in the state of the art and it will not be described further.
[0070] When the closure 10 is first opened, the tamper-evident ring 1 is configured to be separated from the cap 20 and to remain mounted on the neck 30 of the container when the cap 20 is removed from the container to allow access to the liquids therein.It should be noted that this is possible thanks to the advantageous shape and structure of the tamper-evident ring 1, as detailed above.
Claims
CLAIMS1. A tamper-evident ring (1) for a closure (10) comprising a cap (20) for closing the mouth of a container having a neck (30) and a mouth (31), the tamper-evident ring (1) being configured to be mounted on the neck (30) and comprising:- an upper ring (2) configured to engage with an annular seat (21) formed in the cap (20) and having a central axis (A);- a lower part (3) concentric with the upper ring (2) and comprising:- a retaining wall (4) configured to engage with an outer surface (30a) of the neck (30) of the container to retain the tamper-evident ring (1) on the neck (30), - a side wall (5) extending between a first end portion (5a) fixed to the upper ring (2), and a second end portion (5b) fixed to the retaining wall (4), the side wall (5) having an inner surface (6) configured to face the outer surface (30a) of the neck (30), and an opposite outer surface (7) configured to face outwards from the neck (30);characterized in that the outer surface (7) of the side wall (5) is at least partially inclined with respect to the central axis (A) and converges inwardly towards the inner surface (6).
2. A tamper-evident ring (1) according to claim 1, wherein the inner surface (6) of the side wall (5) extends substantially parallel to the central axis (A), the outer surface (7) being at least partially inclined with respect to the inner surface (6).
3. A tamper-evident ring (1) according to claim 1, wherein the outer surface (7) is inclined with respect to the central axis (A) by a substantially constant angle of inclination.
4. A tamper-evident ring (1) according to claim 1, wherein the outer surface (7) comprises a first portion (7a) substantially parallel to the central axis (A) and a second portion (7b) inclined with respect to the central axis (A) by an angle of inclination, the first portion (7a) being closer to the upper ring (2) with respect to the second portion (7b).
5. A tamper-evident ring (1) according to claim 1, wherein the side wall (5) has a first thickness (si) at the first end portion (5a) between the inner surface (6) and the outer surface (7) and a second thickness (s2) at the second end portion (5b) between the inner surface (6) and the outer surface (7), the second thickness (s2) being smaller than the first thickness (si).
6. A tamper-evident ring (1) according to claim 5, wherein the second thickness (s2) is smaller than the first thickness (si) at least of 50%.
7. A tamper-evident ring (1) according to claim 1, wherein the lower part (3) extends along a lower ring concentric to the upper ring (2) and spaced from the upper ring (2) along a longitudinal direction (X-X) parallel to the central axis (A), the lower part (3) comprising two or more segments (3a) shaped as cylindrical sections, each segment (3a) comprising respective retaining wall and side wall, the outer surface (7) of the side wall of each segment (3 a) being inclined with respect to the central axis (A).
8. A tamper-evident ring (1) according to claim 1, wherein the lower part (3) is made in one piece with the upper ring (2) and is configured to remain attached to the upper ring (2) upon first opening of the closure (10).
9. A tamper-evident ring (1) according to claim 1, wherein the retaining wall (4) has an upwardly converging frustoconical shape and a contact wall (4a) configured to engage with a bead (32) of the neck (30) of the container to retain the tamper-evident ring (1) on the neck (30) upon first opening of the closure (10).
10. A closure (1) for closing the mouth (31) of a container comprising:- a cap (20) configured to close the mouth (31) of the container, the cap (20) having an annular seat (21);- a tamper-evident ring (1) according to claim 1 configured to be mounted on a neck (30) of the container, the annular seat (21) being configured to receive and engage the upper ring (2) of the tamper-evident ring (1);wherein the tamper-evident ring (1) is configured to be separated from the cap (20) upon first opening of the closure (10).