SEALING CAP AND CLOSURE COMPRISING THE SAME

Abstract

A sealing cap, which engages a neck of a bottle, including a top wall from which extend a sidewall and a sealing skirt. The sidewall includes a cap thread to be screwed onto a neck thread of the neck of the bottle around a screwing axis. The sealing skirt includes an inclined sealing surface to be pressed against a corresponding surface of the neck on an opposite side from the surface including the neck thread, upon screwing the cap thread onto the neck thread. The inclined sealing surface is formed by a wall of the sealing skirt surrounding a cavity. An inclination angle between the inclined sealing surface and the screwing axis is between 7 and 25. An axial length of the cap thread, taken parallel to the screwing axis, is higher than or equal to 1.5 times a pitch of the cap thread.

Claims

1. A sealing cap to engage a neck of a bottle, the sealing cap comprising a first top wall from which extend a first sidewall and a sealing skirt, wherein: the first sidewall comprises a cap thread to be screwed onto a neck thread of the neck of the bottle around a screwing axis, the sealing skirt comprises an inclined sealing surface to be pressed against a corresponding surface of the neck of the bottle on an opposite side from the surface comprising the neck thread, upon screwing the cap thread onto the neck thread, the inclined sealing surface is formed by a wall of the sealing skirt surrounding a cavity, an inclination angle between the inclined sealing surface and the screwing axis is between 7 and 25, and an axial length of the cap thread, taken parallel to the screwing axis from a level of a proximal end of the inclined sealing surface to a level of a distal end of the cap thread, is higher than or equal to 1.5 times a pitch of the cap thread.

2. The sealing cap according to claim 1, wherein, in an assembled configuration of the sealing cap screwed at a targeted screwing torque on the neck of the bottle, the inclined sealing surface is pressed against the corresponding surface of the neck so that a continuous peripheral contact is formed on the inclined sealing surface, wherein an axial extension of the continuous peripheral contact, taken parallel to the screwing axis, is higher than or equal to 0.05 mm.

3. The sealing cap according to claim 1, wherein, in an assembled configuration of the sealing cap screwed at a targeted screwing torque on the neck of the bottle, the inclined sealing surface is pressed against the corresponding surface of the neck so that a continuous peripheral contact is formed on the inclined sealing surface, wherein an axial extension of the continuous peripheral contact, taken parallel to the screwing axis, is less than or equal to 0.6 mm.

4. The sealing cap according to claim 1, wherein the inclined sealing surface of the sealing skirt is pressed against a substantially cylindrical portion of the corresponding surface of the neck, or a bulge of the corresponding surface of the neck, so that a continuous peripheral contact of limited axial extension, taken parallel to the screwing axis, is formed on the inclined sealing surface.

5. The sealing cap according to claim 1, wherein, when the sealing cap is mounted on the neck of the bottle, the cap thread engages with the neck thread before any contact between the inclined sealing surface and the corresponding surface of the neck.

6. The sealing cap according to claim 1, wherein the sealing cap engages an externally threaded neck of the bottle, and the cap thread is provided on an inner face of the first sidewall while the inclined sealing surface is provided on an outer face of the sealing skirt, wherein the corresponding surface of the neck against which the inclined sealing surface is pressed is an inner surface of the neck, wherein an outer diameter of the sealing skirt at a distal end of the inclined sealing surface, and beyond said distal end, is less than an inner diameter of the neck of the bottle on which the sealing cap is mounted.

7. The sealing cap according to claim 1, wherein the cap thread is screwed onto the neck thread of the bottle at a targeted screwing torque and, in the assembled configuration at the targeted screwing torque, an angular length of engagement of the cap thread with the neck thread is higher than or equal to 270.

8. The sealing cap according to claim 1, wherein the cap thread is screwed onto the neck thread of the bottle at a targeted screwing torque, wherein an evolution of the screwing torque as a function of the angle of rotation of the sealing cap around the screwing axis is substantially linear from a first contact of the inclined sealing surface with the corresponding surface of the neck to the assembled configuration at the targeted screwing torque.

9. The sealing cap according to claim 1, wherein the cap thread is screwed onto the neck thread of the bottle at a targeted screwing torque and, in the assembled configuration at the targeted screwing torque, a gap is formed between an upper surface of the neck and a wall of the sealing cap facing the upper surface of the neck.

10. The sealing cap according to claim 1, wherein an axial length that of the inclined sealing surface, taken parallel to the screwing axis from the level of a proximal end of the inclined sealing surface to the level of a distal end of the inclined sealing surface, is higher than or equal to 1.5 mm.

11. The sealing cap according to claim 1, wherein a radial distance between the cap thread and a proximal end of the inclined sealing surface is higher than or equal to 0.8 mm.

12. The sealing cap according to claim 1, wherein the sealing skirt deforms the neck of the bottle on which the sealing cap is mounted such that, in the assembled configuration at a targeted screwing torque, a variation in a diameter of the neck is higher than or equal to 0.5%.

13. The sealing cap according to claim 1, wherein the sealing skirt having the inclined sealing surface comprises a thermoplastic polymer.

14. The sealing cap according to claim 1, wherein, in the assembled configuration of the sealing cap screwed at a targeted screwing torque on the neck of the bottle, a radial sealing interference between the sealing skirt of the sealing cap and the neck is higher than or equal to 1% of a diameter of the neck.

15. The sealing cap according to claim 1, wherein the wall of the sealing skirt forming the inclined sealing surface surrounds a chamber for receiving an active material for regulating an atmosphere in the bottle equipped with the sealing cap.

16. The sealing cap according to claim 15, wherein the wall of the sealing skirt forming the inclined sealing surface comprises a peripheral wall of the chamber having the inclined sealing surface on its outer face.

17. The sealing cap according to claim 15, wherein the wall of the sealing skirt forming the inclined sealing surface externally surrounds a peripheral wall of the chamber, with a gap between the wall of the sealing skirt and the peripheral wall of the chamber.

18. A closure comprising the sealing cap according to claim 1, wherein the sealing cap is an inner cap to attach the closure to an externally threaded neck of the bottle, wherein the closure further comprises an outer cap with a second top wall and a second sidewall, wherein the sealing cap is coaxially nested in the outer cap.

19. A bottle with the sealing cap according to claim 1, wherein the sealing cap is fixedly screwed onto the thread of a neck of the bottle and closes the bottle.

20. (canceled)

21. The sealing cap according to claim 5, wherein, when the inclined sealing surface first contacts the corresponding surface of the neck of the bottle, an angular length of engagement of the cap thread with the neck thread is higher than or equal to 110.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Features and advantages of the invention will become apparent from the following description of several embodiments of a sealing cap, a closure and a bottle according to the invention, this description being given merely by way of example and with reference to the appended drawings in which:

[0065] FIG. 1 is a perspective top view of a sealing cap according to a first embodiment of the invention;

[0066] FIG. 2 is a perspective bottom view of the sealing cap of FIG. 1;

[0067] FIG. 3 is a cross section at larger scale according to plane III of FIG. 1, in which the relative arrangement of a sidewall and a sealing skirt of the sealing cap is clearly visible;

[0068] FIG. 4 is a perspective view of a bottle with a closure according to a first embodiment of the invention, comprising the sealing cap of FIG. 1 as an inner sealing cap;

[0069] FIG. 5 is a perspective bottom view at larger scale of the outer cap of the closure of FIG. 4;

[0070] FIG. 6 is a cross section at larger scale of only the neck of the bottle of FIG. 4;

[0071] FIG. 7 is a cross section at larger scale according to plane VII of FIG. 4, in a step of mounting the closure on the neck of the bottle in which the sealing skirt of the inner sealing cap is not yet in contact with the inner surface of the bottle neck;

[0072] FIG. 8 is a cross section similar to FIG. 7, in a further step of mounting the closure on the neck of the bottle in which the sealing skirt of the inner sealing cap first comes in contact with the inner surface of the bottle neck;

[0073] FIG. 9 is a cross section similar to FIG. 7, in a final step of mounting the closure on the neck of the bottle in which the thread of the inner sealing cap is screwed on the thread of the bottle neck at a targeted screwing torque such that the bottle is sealed by the inner sealing cap of the closure, it being understood that the deformation of the parts has not been shown in this figure and the interference fit has been shown by an overlap of the sealing skirt and the bottle neck, as is conventional in technical drawing;

[0074] FIG. 10 is a view at larger scale of the detail X of FIG. 9;

[0075] FIG. 11 is an X-ray tomographic view, in the section plane VII of FIG. 4, of a bottle closed by the closure of FIG. 4 with the inner sealing cap of FIG. 1, in the assembled configuration of the sealing cap screwed on the neck of the bottle at the targeted screwing torque, showing the axial extension, parallel to the screwing axis, of the continuous peripheral contact formed on the inclined sealing surface;

[0076] FIG. 12 is a graph showing the evolution of the screwing torque t as a function of the radial sealing interference r between the sealing skirt of the inner sealing cap and the neck of the bottle, upon screwing the closure onto the bottle neck, for two closures including a first closure having a sealing cap within the scope of the invention (labeled as INV for invention) and a second closure having a sealing cap outside the scope of the invention (labeled as COMP for comparative example);

[0077] FIG. 13 is a graph showing the evolution of the screwing torque t as a function of the angle of rotation A of the inner sealing cap around the screwing axis, for the same two closures as in FIG. 12, including the first closure having a sealing cap within the scope of the invention (INV) and the second closure having a sealing cap outside the scope of the invention (COMP);

[0078] FIG. 14 is a perspective bottom view similar to FIG. 2 of a sealing cap according to a second embodiment of the invention;

[0079] FIG. 15 is a cross section similar to FIG. 8 of a closure according to a second embodiment of the invention, comprising the sealing cap of FIG. 14 as an inner sealing cap; and

[0080] FIG. 16 is a cross section similar to FIG. 9 of the closure according to the second embodiment, it being understood that the deformation of the parts has not been shown in this figure and the interference fit has been shown by an overlap of the sealing skirt and the bottle neck, as is conventional in technical drawing.

ILLUSTRATIVE EMBODIMENTS OF THE INVENTION

[0081] In the first embodiment shown in FIGS. 1 to 11, a sealing cap 4 according to the invention is used as an inner part of a child-resistant and tamper-evident closure 1, configured to securely seal different sizes of necks of bottles. In the example shown in FIG. 4, the closure 1 is mounted on a blow molded bottle 10 having an SP400 neck finish with an L style thread. The shape of the bottle 10 shown in the figures only serves as an example, it being understood that the bottle 10 can have any shape, as long as it is provided with a neck 12 which connects a body part 17 to an opening 11 and is surrounded, either externally as shown in the figures, or else internally, by a thread 14 on which the closure 1 can be screwed.

[0082] The SP400 neck finish of the bottle 10 is defined by a set of parameters as shown in FIG. 6, comprising an inner diameter I, an outer diameter E, an outer diameter T at the peak (or crest) of the neck thread 14, a height H from the upper surface 15 of the neck (top of finish, or TOF) to a bead 16, a pitch P of the neck thread 14, a distance K between the start of the neck thread 14 and the upper surface 15 of the neck (TOF), a height (a) of each thread of the neck thread 14. In the example illustrated in the figures, the bottle 10 is provided with a relatively narrow neck 12. However, it is also possible to provide the bottle in the shape of a straight cylinder, the neck then being a portion of the cylinder close to its opening, which is surrounded with a thread. Likewise, it is possible to provide non-rotational geometries for the bottle 10, as long as it is provided with an annular thread, which may be a continuous thread or an interrupted thread.

[0083] The closure 1 comprises two caps which are nested inside each other. FIGS. 1 and 2 show the structure of the inner sealing cap 4, which comprises a sidewall 41 and a top wall 43. As clearly visible in FIG. 3, the sidewall 41 of the sealing cap comprises on its inner face a cap thread 44 configured to be screwed onto the neck thread 14 of the bottle 10, around a screwing axis X.sub.1 which is also the main axis of the closure. In particular, the pitch p of the cap thread 44 is equal to the pitch P of the neck thread 14. In this way, the closure 1 can be screwed onto the bottle neck 12 by rotation in a screwing direction R.sub.1 which, in this example, is a clockwise direction.

[0084] The sealing cap 4 also comprises a sealing skirt 46 configured to establish a sealing contact with an inner surface 13 of the bottle neck 12. As visible in FIG. 3, starting from the top wall 43, the sealing skirt 46 comprises a tapered portion 461 defining on its outer face an inclined sealing surface 47. The tapered portion 461 flares (or widens) from a distal end 472 of the inclined sealing surface 47 furthest from the top wall 43, towards a proximal end 470 of the inclined sealing surface 47 closest to the top wall 43. Thus, the outer diameter d.sub.1 of the sealing skirt 46 at the proximal end 470 is higher than the outer diameter d.sub.2 of the sealing skirt 46 at the distal end 472. Further away from the top wall 43, beyond the distal end 472, the tapered portion 461 is extended by a substantially straight portion 463, then by a thinned extension 465 at its distal end. The inclined sealing surface 47 of the sealing skirt 46 is configured to be pressed against the inner surface 13 of the neck 12 upon screwing the cap thread 44 onto the neck thread 14.

[0085] Advantageously, the outer diameter d.sub.2 of the sealing skirt 46 at the distal end 472 of the inclined sealing surface 47, and beyond said distal end 472, is less than the inner diameter I of the bottle neck 12. In this way, the part of the sealing skirt 46 which is furthest from the top wall 43 serves as a pre-locator when mounting the closure 1 on the bottle neck 12, allowing the sealing skirt 46 to be pre-positioned and pre-centered relative to the neck 12 before the inclined sealing surface 47 contacts the inner surface 13 of the neck. When the closure 1 is mounted on the bottle neck 12, the cap thread 44 engages with the neck thread 14 before contact occurs between the inclined sealing surface 47 and the inner surface 13 of the neck. In this way, the screwing can engage before the sealing skirt 46 starts to be compressed against the inner surface 13. Such an initialization of screwing in the absence of resistance from the sealing skirt 46 promotes the establishment of a homogeneous sealing contact over the entire periphery of the sealing skirt 46 and the bottle neck 12 once the inclined sealing surface 47 comes into contact with the inner surface 13 of the neck. In this embodiment, the sealing skirt 46 is configured so that an angular length of engagement of the cap thread 44 with the neck thread 14 is higher than 110 when the inclined sealing surface 47 first contacts the inner surface 13 of the neck.

[0086] The inclined sealing surface 47 makes it possible to adapt easily to dimensional variations in the thickness of the mouth of the bottle 10. The inclined sealing surface 47 is also configured to ensure a high level of gas tightness when the sealing cap 4 is screwed on standardized bottles or containers. In particular, in accordance with the invention, the inclined sealing surface 47 is designed with an inclination angle relative to the screwing axis X.sub.1 of between 7 and 25, preferably between 10 and 20, and an axial length h.sub.T of the cap thread 44, taken parallel to the screwing axis X.sub.1 from the level of a proximal end 470 of the inclined sealing surface 47 to the level of a distal end 442 of the cap thread 44, of higher than or equal to 1.5 times the pitch p of the cap thread 44. In addition, the axial length h.sub.S of the inclined sealing surface 47, also taken parallel to the screwing axis X.sub.1 from the proximal end 470 to the distal end 472 of the inclined sealing surface 47, is higher than or equal to 2.5 mm, and the radial distance e between the cap thread 44 and the proximal end 470 of the inclined sealing surface 47 is higher than or equal to 1.3 mm.

[0087] The geometric parameters , h.sub.T, h.sub.S, p and e of the sealing cap 4 are clearly visible in FIG. 3. As is conventionally done, for the axial length h.sub.T of the cap thread 44, the positions of the ends of the cap thread 44 are taken in a gauge plane P.sub.0 in the middle of the inclined surface of the thread parallel to the screwing axis X.sub.1. The radial distance e between the cap thread 44 and the proximal end 470 of the inclined sealing surface 47 is measured between the peak of the cap thread 44 and the proximal end 470.

[0088] The cap thread 44 is configured to be screwed onto the neck thread 14 at a targeted screwing torque t.sub.0 as recommended by ASTM D7709 for the given diameter of the sealing cap 4, for example to is in the range of between 1.69 N.Math.m and 2.82 N.Math.m for a diameter of the sealing cap 4 and the bottle neck 12 of 33 mm. Such a range of screwing torque ensures that the closure 1 can be manually opened and closed by a user. The sealing cap 4 is configured such that, in the assembled configuration at the targeted screwing torque t.sub.0, an angular length of engagement of the cap thread 44 with the neck thread 14 is higher than or equal to 270, which corresponds to more than 90 of rotation of the sealing cap 4 after a first contact has been established between the inclined sealing surface 47 and the inner surface 13 of the bottle neck 12. Such a minimum thread engagement in the assembled configuration ensures that a sufficient and homogeneous contact pressure is maintained over the periphery at the interface between the inclined sealing surface 47 and the inner surface 13 of the bottle neck.

[0089] The structure of the outer cap 2 of the closure 1 is visible in FIGS. 4 and 5. The outer cap 2 comprises a sidewall 21 and a top wall 23. The sidewall 21 can be provided with suitable means to increase the grip for a user. In the example shown, a plurality of ribs are provided on the sidewall 21, extending axially in the direction of the screwing axis X.sub.1 of the closure. The top wall 23 comprises a tamper-evident member 24, which is connected to a surrounding region 25 by a frangible structure 26. By way of a non-limiting example, in the illustrated embodiment, the frangible structure comprises four distinct frangible bridges 26 regularly distributed around the periphery of the tamper-evident member 24. In a variant, the frangible structure 26 may be formed by a material of reduced thickness fully surrounding the tamper-evident member 24. The geometry of the outer cap 2 represented in the figures only serves as an example, and other geometries are also possible.

[0090] The top wall 43 of the sealing cap 4 is provided with a protruding element 45 which, as can be seen in FIG. 7, has a geometry corresponding to the geometry of the tamper-evident member 24 being part of the top wall 23 of the outer cap 2. The protruding element 45 is configured to remove the tamper-evident member 24 by breaking the frangible bridges 26 between the tamper-evident member 24 and the surrounding region 25, upon axial displacement of the outer cap 2 toward the sealing cap 4 in the direction of the screwing axis X.sub.1.

[0091] It has been observed from measurements of the Water Vapor Transmission Rate (WVTR) for different values of the geometric parameters of the sealing cap 4 and different bottle neck finish sizes that, when the inclination angle is selected in the range of between 7 and 25, preferably between 10 and 20, and the axial length h.sub.T of the cap thread is selected to be higher than or equal to 1.5 times the pitch p of the cap thread, the sealing cap 4 can be screwed across a wide variety of typical bottle neck finish sizes while ensuring a high level of gas tightness.

[0092] On the contrary, when the inclination angle is less than 7, the sealing skirt 46 cannot compensate for dimensional variations in the inner diameter of the neck of standard bottles, which are typically of the order of +0.7 mm to cover a wide range of blow molded bottles, in particular injection blow molded bottles. When the inclination angle is higher than 25, WVTR values increase rapidly, even when the axial length h.sub.T of the cap thread is equal to or higher than 1.5 times the pitch p of the cap thread. On the other hand, when the axial length h.sub.T of the cap thread is less than 1.5 times the pitch p of the cap thread, the length of mutual engagement of the cap thread and the neck thread obtained for conventional manual screwing torques is not sufficient to ensure a homogeneous sealing contact over the entire periphery of the sealing skirt and the bottle neck, so that WVTR values also increase rapidly.

[0093] In this first embodiment, the sealing skirt 46 also defines a chamber 49 for receiving an active material 19 capable of regulating the atmosphere in the bottle 10, in particular a desiccant and/or an oxygen scavenger. As shown in FIG. 7, the chamber 49 is closed by a gas-permeable cover 18, which retains the active material 19 inside the chamber. In the represented example, the gas-permeable cover 18 is a cardboard held at its periphery by the thinner extension 465 of the sealing skirt 46 which has been crimped. As visible in FIG. 2, axial ribs 40 are provided in the inner surface of the sealing skirt 46 in order to improve the support of the cardboard 18 once the chamber 49 has been filled with an active material 19. In one embodiment, the gas-permeable cover 18 may be a porous membrane secured to the distal end of the sealing skirt 46, e.g., by heat-sealing, ultrasonic welding, overmolding, etc. In a variant, the sealing cap 4 may be provided with a suitable attachment structure for holding a prefabricated canister containing an active material.

[0094] The sidewall 21 of the outer cap 2 comprises a radially inwardly extending bead 22 which, in the mounted state of the outer cap 2 on the sealing cap 4, forms a positive lock with a radially outwardly extending flange 42 provided on the sidewall 41 of the sealing cap 4. The inner bead 22 and the outer flange 42 cooperate in a such a way as to firmly hold the outer cap 2 on the sealing cap 4, so that it can no longer be removed from the sealing cap 4. As can be seen in the bottom view of FIG. 5, the outer cap 2 also comprises several coupling elements formed integrally on that side of the top wall 23 which, in the mounted state, faces the top wall 43 of the sealing cap 4. The coupling elements of the outer cap 2 include, regularly distributed on the surrounding region 25, a plurality of elastic members 52, in the shape of inclined strips, and a plurality of peripheral driving ribs 72. Advantageously, each elastic member 52 has a geometry as described in WO2017220729A1, with a basis extending substantially perpendicularly from the first top wall 23, followed by a transitional portion in which the elastic member 52 changes its direction into an angular position. A reinforcing rib, not represented in the figures, may also be provided next to the basis in a width direction of the elastic member 52, to increase the robustness and stiffness of the elastic member.

[0095] The sealing cap 4 comprises corresponding coupling elements on the upper side of the top wall 43, around the protruding element 45, including a plurality of wedge-shaped elements 54 with beveled inclined surface and a plurality of peripheral serrations 74. Each wedge-shaped element 54 is configured to cooperate with an elastic member 52 of the outer cap, thus forming a first engagement mechanism, whereas each peripheral serration 74 is configured to cooperate with a peripheral driving rib 72 of the outer cap, thus forming a second engagement mechanism. The elastic members 52 are configured to bias the outer cap 2 and the sealing cap 4 away from each other in the direction of the screwing axis X.sub.1, in such a way that the driving ribs 72 of the outer cap 2 are initially not engaged with the serrations 74 of the sealing cap 4.

[0096] When the outer cap 2 is axially displaced toward the sealing cap 4 against the action of the elastic members 52, each driving rib 72 is received in the interspace between two successive serrations 74, more precisely between an edge 74a of a first serration 74 in the direction of screwing R.sub.1 and an edge 74b of a second serration 74 in the direction of unscrewing R.sub.2. By way of a non-limiting example, in this embodiment, the first engagement mechanism comprises five elastic members 52 on the outer cap 2 configured to cooperate with five wedge-shaped elements 54 of the sealing cap 4, and the second engagement mechanism comprises ten driving ribs 72 on the outer cap 2 configured to cooperate with ten serrations 74 of the sealing cap 4.

[0097] In operation, the outer cap 2 and the sealing cap 4 nested therein can be rotated together to mount the closure 1 on the bottle neck 12. The clockwise rotation direction R.sub.1 for screwing the cap thread 44 onto the neck thread 14 brings each elastic member 52 in engagement with a higher edge 54a of a corresponding wedge-shaped element 54, even without any axial force being applied in the direction of the screwing axis X.sub.1. The higher edge 54a provides an abutment for the corresponding elastic member 52, so that the sealing cap is rotated in unison with the outer cap in the direction of screwing R.sub.1. This locking interaction between the elastic members 52 and the wedge-shaped elements 54 without any axial force is possible only when closing the closure 1 on the bottle 10 by rotation in the direction of screwing R.sub.1.

[0098] Upon screwing the cap thread 44 onto the neck thread 14 by rotating the outer cap 2 in the direction of screwing R.sub.1, a sealing contact is progressively established between the inclined sealing surface 47 and the inner surface 13 of the bottle neck 12. The radial distance e between the cap thread 44 and the proximal end 470 of the inclined sealing surface 47 is selected so that there is a clearance between the cap thread 44 and the neck thread 14 at each pair of interengaging peaks and valleys during the assembly of the sealing cap 4 on the bottle neck 12. The clearance advantageously exists at the start of screwing, and preferably at least for the first 90 of screwing. This allows radial deformation of the bottle neck 12 under the pressure of the inclined sealing surface 47 progressively compressed against the inner surface 13 of the neck.

[0099] As shown in the view at larger scale of FIG. 10, in the assembled configuration at the targeted screwing torque t.sub.0 and thanks to the selected inclination angle of the sealing surface 47 and axial length h.sub.T of the cap thread, a sealing interference fit sufficient to ensure a high level of gas tightness is established between the sealing skirt 46 and the bottle neck 12, corresponding to a radial sealing interference r and an axial sealing interference z. In particular, for the parameters of the sealing cap 4 selected within the ranges of the invention, the radial sealing interference r in the assembled configuration is higher than or equal to 1% of the inner diameter I of the bottle neck 12, which may be approximated as 1% of the outer diameter d.sub.1 of the sealing skirt 46 at the proximal end 470 of the sealing surface 47.

[0100] It is understood that the deformation of the parts is not shown in FIGS. 9 and 10, where the interference fit is represented by an overlap of the sealing skirt 46 and the bottle neck 12, the sealing cap 4 and the bottle neck 12 being represented in their state before assembly, as is conventional in technical drawing. In other words, FIGS. 9 and 10 do not consider the elastic deformation which occurs when the sealing cap 4 is screwed on the bottle neck 12.

[0101] On the contrary, FIG. 11 is an X-ray tomographic view showing the deformation of the parts and the actual axial extension d of the continuous peripheral contact formed on the inclined sealing surface 47, which is less than the axial sealing interference z as shown in FIG. 10. In the example of FIG. 11, the bottle neck 12 includes a bulge 130 adjacent to the upper surface 15 of the bottle neck. The inclined sealing surface 47 of the sealing skirt 46 is pressed against the bulge 130 of the inner surface 13 so that continuous peripheral contact of limited axial extension d, taken parallel to the screwing axis X.sub.1, is present over the periphery. In this example, the axial extension d of the continuous peripheral contact is of the order of 0.45 mm. Such a limited axial extension d of the continuous peripheral contact provides sufficient resistance to the transmission of water vapor through the seal so as to achieve desired moisture barrier properties of the bottle closed by the sealing cap, while also ensuring that a high contact pressure is established in a well-defined annular sealing zone of limited surface area, as a result of the elastic deformation of the sealing skirt 46 and/or the bottle neck 12.

[0102] Advantageously, in the assembled configuration at the targeted screwing torque t.sub.0, a gap G is formed between the upper surface 15 of the bottle neck 12 and the portion of the top wall 43 of the sealing cap 4 which faces the upper surface 15 of the bottle neck. In addition, at least at the start of screwing, there is a clearance between the cap thread 44 and the neck thread 14 at each pair of interengaging peaks and valleys. In this way, the targeted screwing torque t.sub.0 is reached by interference fit between the inclined sealing surface 47 and the inner surface 13 of the bottle neck, with a radial deformation of the bottle neck 12. The clearance between the cap thread 44 and the neck thread 14 at each pair of interengaging peaks and valleys may optionally still be present in the assembled configuration at the targeted screwing torque t.sub.0, or alternatively radial contact may be established between the threads in the assembled configuration.

[0103] When a user rotates the outer cap 2 in a counterclockwise direction R.sub.2 for unscrewing the cap thread 44 relative to the neck thread 14, in an attempt to open the closure 1 without applying an axial force on the outer cap 2 in the direction of the screwing axis X.sub.1, the elastic members 52 slip over the beveled inclined surfaces of the wedge-shaped elements 54. As a result, the rotation of the outer cap 2 does not lead to a corresponding rotation of the sealing cap 4. Of course, the same construction and functionalities can be provided in case that the rotational directions R.sub.1 and R.sub.2 for closing and opening the bottle 10 should be reversed. By way of a non-limiting example, in the illustrated embodiment, the height h.sub.1 of the higher edge 54a of each wedge-shaped element 54 is of the order of 1 mm, whereas the height of the lower edge 54b of each wedge-shaped element 54 is substantially zero.

[0104] An opening of the closure 1 requires that the driving ribs 72 of the outer cap 2 are brought in engagement with the edges 74b of the serrations 74 of the sealing cap 4. This is only possible after the outer cap 2 has been axially displaced toward the sealing cap 4, against the action of the elastic members 52 biasing the outer and sealing caps away from each other in the direction of the screwing axis X.sub.1. When an axial pushing force F is applied onto the top surface of the top wall 23 in the direction of the screwing axis X.sub.1, as shown in FIG. 9, each driving rib 72 is received in the interspace between two successive serrations 74 and, upon rotation of the outer cap 2 in the counterclockwise direction of unscrewing R.sub.2, can interact with the neighboring serration edge 74b, so that the sealing cap 4 is also rotated in the same direction of unscrewing R.sub.2. Then, when the axial pushing force F on the outer cap 2 is released, the elastic members 52 exert a biasing force toward disengagement of the driving ribs 72 and serrations 74, so that the elastic members 52 can return to their relaxed position and displace the outer cap 2 away from the sealing cap 4 in the direction of the screwing axis X.sub.1.

[0105] The gas tightness of blow molded bottles closed by a closure 1 having the structure of the first embodiment of the invention, comprising the outer cap 2 and the sealing cap 4, was determined by measurements of the Water Vapor Transmission Rate (WVTR) according to ASTM-D7709. To evaluate the effect of the geometric parameters of the sealing cap 4 on the resulting gas tightness, the WVTR values were obtained for different values of the inclination angle of the sealing surface 47 and the axial length h.sub.T of the cap thread 44.

Example 1

[0106] In this example, two sets of child-resistant and tamper-evident closures 1.sub.1 and 1.sub.2, comprising a respective sealing cap 4.sub.1 or 4.sub.2, were assembled on a same model of blow molded bottle 10 having an SP400 neck finish of size 33 mm with an L-style thread (L33-SP400 neck finish according to the format used in the SP400 standard).

[0107] In a first test, the bottles 10 with L33-SP400 neck finish, on which each set of closures 11 and 12 were assembled, had a volume of 45 mL, an overflow capacity of 53.63.0 mL, an empty weight of 7.70.5 g, an average wall thickness of 0.9 mm (with a minimum wall thickness of 0.5 mm), a neck inner diameter I in the range of 25.8 to 25.9 mm, with a maximum ovality of 0.3 mm.

[0108] In a second test, the bottles 10 with L33-SP400 neck finish, on which each set of closures 1.sub.1 and 1.sub.2 were assembled, had a volume of 60 mL, an overflow capacity of 68.03.0 mL, an empty weight of 9.20.5 g, an average wall thickness of 0.9 mm (with a minimum wall thickness of 0.3 mm), a neck inner diameter I in the range of 25.6 to 25.8 mm, with a maximum ovality of 0.3 mm.

[0109] Both for the 45 ml bottles and the 60 ml bottles, the bottle was injection blow molded from High Density Polyethylene (Marlex HHM 5502BN HDPE available from Chevron Phillips, with a density of 0.955 g/cm.sup.3 and a flexural modulus of 1370 MPa). In accordance with the SP400-33 mm standard, the bottle neck had a height H from the upper surface 15 of the neck (top of finish, or TOF) to the bead 16 of 10.24 mm and was provided with an L-style thread with one full turn, having a pitch P of 4.24 mm and starting at 1.2 mm from the upper surface 15 of the neck (TOF), with a distance K between the start of the neck thread and the upper surface 15 of the neck (TOF) of 3.23 mm and a height (a) of each thread of 2.39 mm.

[0110] Each sealing cap 4.sub.1 and 4.sub.2 was a single piece injection molded from High Density Polyethylene (Purell GC7260 HDPE available from Lyondell Basell, with a density of 0.960 g/cm.sup.3 and a tensile modulus of 1350 MPa), having the structure described above in the first embodiment of the invention. The sidewall 41 of each sealing cap 4.sub.1 and 4.sub.2 was provided on its inner face with a right-hand cap thread 44 compliant with the SP400-33 mm standard, requiring a minimum of one full turn of full depth thread on the bottle neck. For each sealing cap 4.sub.1 and 4.sub.2, the helix angle of the cap thread was 231, corresponding to a pitch p of the cap thread of 4.24 mm.

[0111] Each sealing cap 4.sub.1 and 4.sub.2 was mounted in an outer cap 2 having the structure described above in the first embodiment of the invention, the outer cap being injection molded from Polypropylene (Purell HP671T PP available from Lyondell Basell, with a density of 0.90 g/cm.sup.3 and a tensile modulus of 1900 MPa). Each sealing cap 4.sub.1 and 4.sub.2 was assembled with an outer cap 2 in the manner shown in FIGS. 7 to 9, so as to form the two-component closures 1.sub.1 or 1.sub.2.

[0112] The geometric parameters of the sealing caps 4.sub.1 and 4.sub.2 are given in the table below. The sealing cap 4.sub.1 is within the scope of the invention, whereas the sealing cap 4.sub.2 is outside the scope of the invention.

TABLE-US-00001 Sealing Sealing cap 4.sub.1 cap 4.sub.2 11.5 35 (inclination angle of sealing surface 47) h.sub.T 7.45 mm 6.2 mm (axial length of cap thread 44) (=1.75 p) (=1.45 p) h.sub.S 3.20 mm 1.45 mm (axial length of sealing skirt 46) d.sub.1 26.75 mm 27.25 mm (outer diameter of sealing skirt at proximal end of sealing surface 47) d.sub.2 25.45 mm 25.00 mm (outer diameter of sealing skirt at distal end of sealing surface 47) e 1.60 mm 1.20 mm (radial distance between cap thread 44 and proximal end of sealing surface 47) p 4.24 mm 4.24 mm (pitch of cap thread 44)

[0113] For each closure 1.sub.1 and 1.sub.2 comprising a respective sealing cap 4.sub.1 or 4.sub.2, the cap thread 44 was screwed on the neck thread of the bottle 10 until a targeted screwing torque t.sub.0 of 2.4 N.Math.m was reached.

[0114] FIG. 12 shows the evolution of the screwing torque t as a function of the radial sealing interference r between the sealing skirt of the sealing cap and the neck of the bottle, for two closures 1.sub.1 and 1.sub.2 comprising a respective sealing cap 4.sub.1 or 4.sub.2. It can be seen from FIG. 12 that the screwing torque t to be applied is substantially proportional to the radial sealing inference r, independently of the inclination angle of the sealing surface 47. This tends to show that an adjustment of the inclination angle of the sealing surface 47 alone is not sufficient to obtain good sealing properties, and that other geometric parameters of the sealing cap 4 have to be adjusted in combination with the inclination angle , in particular the axial length h.sub.T of the cap thread 44.

[0115] FIG. 13 shows the evolution of the screwing torque t as a function of the angle of rotation A of the sealing cap around the screwing axis, for two closures 1.sub.1 and 1.sub.2 comprising a respective sealing cap 4.sub.1 or 4.sub.2. By convention, in the graph of FIG. 13, an angle A of 0 corresponds to the position in which the inclined sealing surface 47 of the sealing skirt first contacts the inner surface 13 of the bottle neck. Starting from this position, the screwing torque t increases as the pressure generated at the interface between the sealing skirt 46 and the inner surface 13 of the bottle neck increases.

[0116] As shown in FIG. 13, the targeted screwing torque t.sub.0 of 2.4 N.Math.m was reached for an angle of rotation A of the order of 100 for the closure 1.sub.1 comprising the sealing cap 4.sub.1 within the scope of the invention, having an inclination angle of the sealing surface of 11.5 and an axial length h.sub.T of the cap thread equal to 1.75 times the pitch p. The targeted screwing torque t.sub.0 of 2.4 N.Math.m was reached for an angle of rotation A of the order of 35 for the closure 1.sub.2 comprising the sealing cap 4.sub.2 outside the scope of the invention, having an inclination angle of the sealing surface of 35 and an axial length h.sub.T of the cap thread equal to 1.45 times the pitch p.

[0117] It can also be seen in FIG. 13 that for both closures 1.sub.1 and 1.sub.2, starting from the first contact between the inclined sealing surface 47 and the inner surface 13, the evolution of the screwing torque t as a function of the angle of rotation A is substantially linear. In particular, for the closure 1.sub.1 comprising the sealing cap 4.sub.1 within the scope of the invention, the evolution of the screwing torque t as a function of the angle of rotation A is substantially linear for at least 90 of rotation of the sealing cap after the first contact between the inclined sealing surface 47 and the inner surface 13.

[0118] WVTR values were measured according to ASTM-D7709, at 40 C. and 75% RH, for the bottles 10 described above, equipped either with the closure 1.sub.1 comprising the sealing cap 4.sub.1 within the scope of the invention, or with the closure 1.sub.2 comprising the sealing cap 4.sub.2 outside the scope of the invention. In each case, the cap thread 44 was screwed onto the neck thread 14 of the bottle at the targeted screwing torque to of 2.4 N.Math.m. The WTR measurements are given in the table below.

TABLE-US-00002 WVTR (mg/bottle-day) WVTR (mg/bottle-day) of bottle closed by closure 1.sub.1 of bottle closed by closure 1.sub.2 comprising sealing cap 4.sub.1 comprising a sealing cap 4.sub.2 Sam- (within scope of invention) (outside scope of invention) ple # 45 mL 60 mL 45 mL 60 mL 1 1.24 1.44 7.55 35.53 2 1.00 1.73 6.91 2.08 3 1.00 1.86 4.77 10.83 4 1.01 1.57 6.84 2.31 5 0.96 1.59 4.92 8.19 6 0.96 1.50 5.89 1.96 7 1.48 1.70 5.60 7.25 8 1.08 1.45 5.79 2.44 9 0.97 1.95 3.43 7.02 10 1.15 1.72 3.79 2.53 11 1.54 1.58 5.50 5.72 12 1.18 1.37 3.81 3.97 13 1.22 1.43 3.76 8.71 14 1.05 1.34 8.43 2.81 15 1.28 1.62 8.57 2.88 Minimum 0.96 1.34 3.43 1.96 Maximum 1.54 1.95 8.57 35.53 Average 1.14 1.59 5.70 6.95 Range 0.58 0.61 5.13 33.57 Standard 0.18 0.18 1.68 8.41 Deviation RSD (%) 16% 11% 29% 121%

[0119] As can be seen from the above table, the WTR measured for the closure 1.sub.1 was less than 3.5 times the WVTR measured for the closure 1.sub.2. The closure 1.sub.1, comprising a sealing cap 4.sub.1 whose values of the inclination angle and the axial length h.sub.T fall within the ranges of the invention, provided good sealing properties. On the contrary, despite a similar radial sealing interference r at the targeted screwing torque t.sub.0 of 2.4 N.Math.m, as shown in the graph of FIG. 12, the closure 1.sub.2 comprising a sealing cap 4.sub.2 outside the scope of the invention failed to establish a good sealing of the bottle.

[0120] It has been observed that, in the case of the closure 1.sub.2, because of the high value of the inclination angle of the sealing cap 4.sub.2, the length of mutual engagement of the cap thread 44 with the neck thread 14, obtained at the targeted screwing torque to of 2.4 N.Math.m, was not sufficient to ensure a homogeneous sealing contact over the entire periphery of the sealing skirt 46 and the bottle neck 12. Then, the sealing pressure was unevenly distributed around the periphery of the bottle neck. In particular, in the assembled configuration at the targeted screwing torque t.sub.0, it was found that the angular length of engagement of the cap thread 44 with the neck thread 14 was less than 270, which did not allow sufficient vertical pressure to be applied to the seal, so that the closure 1.sub.2 was raised on the side where the cap thread 44 was not sufficiently engaged with the neck thread 14.

[0121] Hence, according to the invention, to obtain good sealing properties, it is taught not only to select values for the inclination angle , but also to select a minimum value for the axial length h.sub.T of the cap thread 44, which must be greater than 1.5 times the pitch p of the cap thread, so that the length of the mutual engagement of the cap thread 44 with the neck thread 14 obtained at a conventional manual screwing torque t.sub.0 is greater than or equal to 270, thus ensuring a high and homogeneous sealing contact on the periphery of the sealing skirt and of the neck of the bottle.

[0122] The Water Vapor Transmission Rate (WVTR) induced by the closure 1.sub.1 comprising the sealing cap 4.sub.1 was also determined. In the context of the invention, the WVTR induced by the closure 1.sub.1 comprising the sealing cap 4.sub.1 is defined as the difference between, on the one hand, the WVTR of the assembly comprising a bottle 10 and the closure 1.sub.1 comprising the sealing cap 4.sub.1 screwed onto the neck thread 14 at the targeted screwing torque t.sub.0 of 2.4 N.Math.m and, on the other hand, the WVTR of the same bottle 10 (same size and same material) sealed with an aluminum foil seal, the WVTR values being measured according to ASTM-D7709.

[0123] Accordingly, WVTR values were measured according to ASTM-D7709, at 40 C. and 75% RH, for 60 mL blow molded bottles as described above, which had been sealed by induction sealing with an aluminum foil seal. The resulting average WVTR measured for the bottles sealed with an aluminum foil seal was 1.18 mg/bottle-day (Minimum: 1.15; Maximum: 1.23; Standard Deviation: 0.025).

[0124] The values of the WVTR induced by the closure 1.sub.1 comprising the sealing cap 4.sub.1 were then obtained by subtracting 1.18 mg/bottle-day from the WVTR values disclosed in the table above, for the 60 ml bottles closed by the closure 1.sub.1 comprising the sealing cap 4.sub.1. The values of the WTR induced by the closure 1.sub.1 comprising the sealing cap 4.sub.1 are given in the table below.

TABLE-US-00003 WVTR (mg/bottle-day) of bottle closed by WVTR (mg/bottle-day) closure 1.sub.1 comprising induced by sealing cap 4.sub.1 closure 1.sub.1 comprising Sam- (within scope of invention) sealing cap 4.sub.1 ple # 60 mL (within scope of invention) 1 1.44 0.26 2 1.73 0.55 3 1.86 0.68 4 1.57 0.39 5 1.59 0.41 6 1.50 0.32 7 1.70 0.52 8 1.45 0.27 9 1.95 0.77 10 1.72 0.54 11 1.58 0.40 12 1.37 0.19 13 1.43 0.25 14 1.34 0.16 15 1.62 0.44 Minimum 1.34 0.16 Maximum 1.95 0.77 Average 1.59 0.41 Range 0.61 0.61 Standard 0.18 0.18 Deviation

[0125] It can be seen from the above table that the Water Vapor Transmission Rate (WVTR) induced by the closure 1.sub.1 comprising the sealing cap 4.sub.1 is less than 1 mg/bottle-day, at 40 C. and 75% RH.

Example 2

[0126] In order to evaluate an upper limit of the range for the inclination angle allowing to obtain good sealing properties, another set of child-resistant and tamper-evident closures 1.sub.3 was prepared, each comprising a sealing cap 4.sub.3 with the geometric parameters given in the table below. Each closure 1.sub.3 differs from the closure 1.sub.1 of Example 1 only in the geometric parameters of the sealing cap 4.sub.3 as disclosed below, it being understood that all other features of the closure 1.sub.3 are identical to those of the closure 1.sub.1.

TABLE-US-00004 Sealing cap 4.sub.3 20.3 (inclination angle of sealing surface 47) h.sub.T 7.10 mm (axial length of cap thread 44) (=1.65 p) h.sub.S 3.05 mm (axial length of sealing skirt 46) d.sub.1 27.50 mm (outer diameter of sealing skirt at proximal end of sealing surface 47) d.sub.2 26.40 mm (outer diameter of sealing skirt at distal end of sealing surface 47) e 1.20 mm (radial distance between cap thread 44 and proximal end of sealing surface 47) p 4.24 mm (pitch of cap thread 44)

[0127] In Example 2, a set of closures 13 and a set of closures 12 as described in Example 1 were assembled on a same model of blow molded bottle 10 having an SP400 neck finish of size 33 mm with an L-style thread (L33-SP400 neck finish according to the format used in the SP400 standard). Each bottle 10 had a volume of 90 mL, an overflow capacity of 53.63.0 mL, an empty weight of 7.70.5 g, an average wall thickness of 0.9 mm (with a minimum wall thickness of 0.5 mm), an overflow capacity of 99.04.0 mL, an empty weight of 10.50.5 g, an average wall thickness of 0.9 mm (with a minimum wall thickness of 0.3 mm), a neck inner diameter I in the range of 26.3 to 26.9 mm, with a maximum ovality of 0.3 mm. Each bottle 10 was injection blow molded from High Density Polyethylene (Petrothene LR734045 HDPE available from Lyondell Basell, with a density of 0.953 g/cm.sup.3 and a flexural modulus of 1210 MPa). In accordance with the SP400-33 mm standard, the bottle neck had a height H from the upper surface 15 of the neck (top of finish, or TOF) to the bead 16 of 10.24 mm and was provided with an L-style thread with one full turn, having a pitch P of 4.24 mm and starting at 1.2 mm from the upper surface 15 of the neck (TOF), with a distance K between the start of the neck thread and the upper surface 15 of the neck (TOF) of 3.23 mm and a height (a) of each thread of 2.39 mm.

[0128] WVTR values were measured according to ASTM-D7709, at 40 C. and 75% RH, for the 90 ml bottles 10 described above, equipped either with the closure 1.sub.3 comprising the sealing cap 4.sub.3, or with the closure 1.sub.2 comprising the sealing cap 4.sub.2. In each case, the cap thread 44 was screwed onto the neck thread 14 of the bottle at the targeted screwing torque t.sub.0 of 2.4 N.Math.m. The WTR measurements are given in the table below.

TABLE-US-00005 WVTR (mg/bottle-day) WVTR (mg/bottle-day) of bottle closed by closure 1.sub.3 of bottle closed by closure 1.sub.2 comprising sealing cap 4.sub.3 comprising a sealing cap 4.sub.2 Sam- (within scope of invention) (outside scope of invention) ple # 90 mL 90 mL 1 1.47 7.82 2 1.47 7.34 3 1.55 4.38 4 1.62 5.34 5 1.49 7.07 6 1.52 6.99 1.66 6.70 8 1.62 8.26 9 1.68 4.53 10 1.48 11.22 11 6.53 12 6.22 13 10.05 14 2.02 15 3.76 Minimum 1.47 3.43 Maximum 1.56 5.70 Average 1.68 8.57 Range 0.21 5.13 Standard 0.08 1.68 Deviation RSD (%) 5% 29%

[0129] As can be seen from the above table, the closure 1.sub.3 comprising the sealing cap 4.sub.3 having an inclination angle of 20.3 and an axial length h.sub.T of 1.65 p was still found to provide satisfactory sealing properties. According to the invention, the inclination angle of the inclined sealing surface 47 is selected to be between 7 and 25, preferably between 10 and 20, in combination with an axial length h.sub.T of higher than or equal to 1.5 p.

[0130] It is understood that the lower limit of the range for the inclination angle , allowing to obtain good sealing properties, was determined based on the available space for the axial displacement z of the sealing cap 4, which is limited by the presence of a bead 16 or a shoulder on the bottle neck 12. The maximum axial translation z of the sealing cap 4 must remain less than HK(a), where H, K, (a) are parameters of the SP400-33 mm standard. Thus, the axial displacement z, which corresponds to the axial sealing interference fit, must remain less than or equal to HK(a)=10.24 mm-3.45 mm-2.39 mm=4.40 mm. In addition, the radial sealing interference r should be higher than or equal to 1% of the outer diameter d.sub.1 of the sealing skirt 46 at the proximal end 470 of the sealing surface 47 and should also allow to absorb inner diameter variations of the order of +0.7 mm to cover a wide range of blow molded bottles, in particular injection blow molded bottles. Thus, the radial sealing interference r must be higher than or equal to 1% d.sub.1+0.7/2=0.60 mm, considering a low value of d.sub.1 of 25 mm. The double condition of z4.4 mm and r0.60 leads to tan()=r/z0.14, i.e. 7.

[0131] In the second embodiment shown in FIGS. 14 to 16, elements that are similar to those of the first embodiment have the same references. The closure 1 of the second embodiment differs from the first embodiment only in that the sealing skirt 46 of the sealing cap 4 is independent from a peripheral wall 48 of the chamber 49 intended to receive an active material 19. More precisely, the peripheral wall 48 of the chamber 49 is externally surrounded by the sealing skirt 46 having the inclined sealing surface 47 on its outer face, and a gap is defined between the peripheral wall 48 of the chamber and the sealing skirt 46. Otherwise, all the geometric parameters , h.sub.T, h.sub.S, p and e of the sealing cap 4 are substantially the same as in the first embodiment.

[0132] In all embodiments, the outer cap 2 and the sealing cap 4 are advantageously manufactured by injection molding of suitable polymer material(s), which may be one and the same polymer material for all of the outer cap and the sealing cap, or different polymer materials selected according to the intended function of each cap, or even according to the intended function of each portion of each cap. Examples of suitable polymers for both caps include polyolefin-based polymers, in particular polyethylene or polypropylene. In one embodiment, the constitutive polymer of the outer cap 2 is the same as the constitutive polymer of the sealing cap 4, e.g. high-density polyethylene (HDPE). In another embodiment, the constitutive polymer of the outer cap 2 is different from the constitutive polymer of the sealing cap 4, e.g. the outer cap may be made of polypropylene (PP) or polyoxymethylene (POM), whereas the sealing cap may be made of high-density polyethylene (HDPE). Advantageously, the sealing cap is a single piece, injection molded from a single polymer material, in particular high-density polyethylene (HDPE). Polypropylene (PP) and polyoxymethylene (POM) are polymer materials that are advantageous for the outer cap, especially as they are materials that are brittle enough to allow the rupture of the frangible structure 26, but they are also flexible materials, which is required for the elastic properties of the outer cap.

[0133] As can be seen from the above description of several embodiments and examples, the invention provides a universal sealing cap for different sizes of bottle necks. When screwed onto a bottle neck at a conventional screwing torque, a sealing cap according to the invention, or a closure comprising such a sealing cap, make it possible to safely preserve sensitive products stored in the bottle, while also allowing easy handling of the sealing cap by a user to open and close the bottle manually. A closure comprising a sealing cap according to the invention and an outer cap also makes it possible to combine the three functions of being child-resistant, tamper-evident and providing active control of the atmosphere in the bottle. Because of its high safety as being gas-tight, childproof and tamper-evident, a bottle with a closure according to the invention is advantageously used for storing tablets or capsules containing a pharmaceutical composition; nutraceuticals; herbalism products; or diagnostic products.

[0134] The invention is not limited to the examples described and shown.

[0135] In particular, in one variant, the sealing skirt forming the inclined sealing surface of the sealing cap may be attached to the rest of the sealing cap, instead of being made in one piece with the rest of the sealing cap.

[0136] In another variant, the bottle neck may comprise an internal thread on its inner surface, instead of an external thread on its outer surface as shown in the figures. In this case, the first side wall of the sealing cap extends from the first top wall while being positioned internally with respect to the sealing skirt, and the cap thread is provided on the outer face of the first side wall whereas the inclined sealing surface is provided on the inner face of the sealing skirt and configured to be pressed against the outer surface of the neck upon screwing the cap thread onto the neck thread.

[0137] Of course, many other variants can be considered, falling within the scope of the appended claims.