IT201700020547A1 - BOTTLE AND SCREW CAP FOR SUCH BOTTLE - Google Patents

Description

"BOTTLE AND SCREW CAP FOR SAID BOTTLE"

Description

Technical field

The present invention relates to plastic containers, in particular plastic bottles for beverages, such as mineral water, carbonated beverages and the like.

Front art

The use of plastic bottles to package mineral water and other beverages is extremely widespread. Plastic bottles are normally fitted with a screw cap, or capsule, which engages the bottle and which has a security seal which is broken when the bottle is first opened and which provides the consumer with a guarantee of integrity. of the contents of the bottle at the time of purchase.

Modern large bottling plants fill tens of thousands of bottles a day, and in some cases hundreds of thousands of bottles. Consequently they consume a large number of this type of container. There is a constant search for new ways to reduce the weight of each bottle and cap, firstly to reduce production costs and secondly to reduce the environmental impact of this type of packaging as well, considering that not all plastic bottles are recycled.

Plastic bottles of this type usually have a threaded neck and, between the thread and the body of the bottle, two annular edges, one used to couple the security seal and the other to handle the bottles in filling systems.

WO-A-2009/053921 discloses a plastic bottle, in which the neck of the bottle has a single annular edge used both to engage the bottle with manipulation and conveying members inside the filling system, and to constrain the seal warranty. To allow handling of the bottle, an annular groove is provided between the threaded neck of the bottle and the annular rim. The groove is arranged for engagement with mechanical handling members during the filling and conveying process.

The use of a single annular rim instead of the conventional two annular rims reduces the weight of each bottle by a few grams, which results in a saving of many tons of plastic per year.

WO-A-2009/146567 discloses a cap with a security seal for a bottle, wherein the cap comprises a side wall and an internal thread formed on the internal surface of the side wall. The side wall of the cap comprises a safety element in the form of a tab which cooperates with the thread of the bottle, so as to be irreversibly altered when the screw cap is removed from the bottle. The bottle is provided with a rim placed between the bottle body and the thread.

An additional bottle and cap with warranty seal designed to reduce the amount of plastic required for their production are described in WO-A-2014/108781.

These known systems reduce the amount of plastic used to produce bottles and caps. However, there is still scope to improve this and to further reduce the amount of plastic material required to produce each bottle. Furthermore, the security seals of the caps of the current art are not satisfactory and are difficult to produce.

Summary of the invention

According to one aspect, a bottle is disclosed herein comprising: a body, a bottle neck forming a bottle mouth and having an external surface forming an external thread. The bottle further comprises an annular shoulder between the body and the external thread. The annular shoulder extends radially inward from the outer surface of the bottle neck to a bottle neck axis. In embodiments described here, the annular shoulder has an annular flat surface substantially orthogonal to the axis of the bottle neck. The bottle further comprises a series of radial projections disposed on the external surface of the bottle neck between the external thread and the annular shoulder, and extending radially outward from the external surface.

The radial projections are adapted to engage in openings or slots formed in a safety ring of a screw cap adapted to close the bottle.

The radial projections may have a first and second flank and a second flank converging towards each other in an outward radial direction, so that the circumferential extension of each protrusion is greater on the inside diameter and smaller on the outside diameter. of it.

According to some embodiments, the projections are arranged along the annular shoulder and adjacent thereto, so that the overall axial dimension of the bottle neck is minimized, thereby reducing the amount of plastic required for its production.

For easier use of the bottle and the respective screw cap, according to some embodiments the projections are distributed with a constant angular pitch around the axis of the bottle neck.

In order to facilitate the application of the screw cap on the bottle, and to ensure correct operation of the safety ring, each projection can be provided with two asymmetrical radial sides. The shape of the sides is such that screwing a safety cap onto the bottle is made easy, without breaking the safety ring of the cap, while unscrewing the cap will cause the safety ring to break.

In order to further facilitate the screwing of the screw cap onto the bottle, according to some embodiments each protrusion can be provided with an inclined outer surface, which extends radially outwards and is inclined from the mouth towards the body of the bottle.

According to some embodiments, the bottle may comprise an annular edge extending from the outer surface of the neck. The annular edge can be disposed along the annular shoulder. The projections can be arranged on the annular edge and project radially outwards therefrom. In this way, the radial dimension of each protrusion can be small, which avoids the risk for the user of injury due to the protrusions when using the bottle.

In some embodiments, the annular edge may have an outside diameter equal to or less than the outside diameter of the external thread. The amount of plastic required for the production of the annular edge is therefore negligible. The annular edge can be flush with the annular shoulder of the bottle neck and can form a radial extension of it.

According to a further aspect, a screw cap for a bottle is described here, comprising a lateral circumferential wall which extends around an axis of the cap, from an upper wall to a circular lower edge, and a security seal. The lateral circumferential wall has an inner surface and an outer surface. The internal surface forms an internal thread. The security seal comprises a cylindrical lip formed along the lower edge and extending axially therefrom. Openings are provided along the cylindrical lip.

The openings can be arranged in a constant pitch. In some embodiments, the openings can be spaced from each other by a greater distance than the circumferential dimension of an opening.

The openings can be formed by slots extending in a circumferential direction around the axis of the cap, i.e. having a larger size in the circumferential direction and a smaller size in the axial direction, i.e. in a direction parallel to the axis of the cap.

The openings are preferably arranged near the lower edge of the circumferential side wall, preferably at a junction between the cylindrical lip and the lower edge of the side circumferential wall.

According to a further aspect, the present description also relates to a system comprising a bottle and a screw cap as described above, in which the radial projections of the bottle are adapted to engage in the openings of the cap.

The cylinder lip and its openings are configured so that once the screw cap has been screwed onto the bottle, the subsequent unscrewing will cause the bottle protrusions to tear off the cylindrical lip leaving the cylindrical lip connected to the screw cap.

A further aspect of the present description relates to a preform for producing a bottle as described herein. The preform comprises a body suitable for forming the body of the bottle, a neck forming an opening and having an external surface forming an external thread. The preform further comprises an annular shoulder between the body and the external thread. The annular shoulder extends radially inward from the outer surface of the neck to an axis of the preform. In embodiments described herein, the annular shoulder has a planar annular surface substantially orthogonal to the axis of the preform. The preform further comprises a series of radial projections arranged on the external surface of the neck, between the external thread and the annular shoulder, and extending radially outward from the external surface. The preform may further comprise one or more of the aforementioned characteristics of the bottle.

Further features and embodiments of the invention are described below and are defined in the attached claims, which form an integral part of the present description.

Brief description of the drawings

The invention will be better understood by following the description and the attached drawing, which shows a practical non-limiting embodiment of the invention. More specifically, in the drawing: the

Fig.1 shows a side view of a portion of the neck of a bottle and a cap in one embodiment; there

Fig.2 shows a cross section along the line II-II of Fig.1; Fig.3 shows an axonometric view of the neck of the bottle of Fig.1; Fig.4 shows a cross section along a line IV-IV of Fig.1; Fig.5 shows an enlargement of the detail V of Fig.1; there

Fig.6 shows an enlargement of the detail VI of Fig.2; there

Fig.7 shows an enlargement of detail VII of Fig.4; there

Fig.8 shows a view of the cap of Fig.1; there

Fig.9 shows a sectional view of a preform for producing a bottle according to Fig.1.

Detailed description of an embodiment of the invention

The following detailed description of exemplary embodiments refers to the accompanying drawings. The same reference numerals in different drawings identify the same or similar elements. Also, the drawings are not necessarily to scale. Furthermore, the detailed description that follows does not limit the invention. On the contrary, the scope of the invention is defined by the attached claims.

Reference throughout the description to "an embodiment" or "the embodiment" or "some embodiment" means that a particular feature, structure or element described in connection with an embodiment is included in at least one embodiment of realization of the described object. Therefore the phrase "in an embodiment" or "in the embodiment" or "in some embodiment" at various points along the description does not necessarily refer to the same or the same embodiments. Furthermore, the particular features, structures or elements can be combined in any suitable way in one or more embodiments.

Hereinafter, specific reference will be made to an embodiment, in which the plastic container is a bottle, for example a beverage bottle, such as mineral water or the like. However, it must be understood that the concept on which the invention is based can also be incorporated in other types of plastic containers with similar needs and technical-functional characteristics similar to those of water and / or beverage bottles.

Fig.1 illustrates a partial side view of a bottle 101, for example a plastic bottle for water and / or other beverages. More specifically, Fig.1 illustrates the upper portion of the bottle body 101B and the bottle neck 101A, as well as a screw cap 103, which is in the closed position.

A preform 101P suitable for the production of the bottle 101 can be shaped as shown in Fig.9. The same reference numerals are used to designate the same parts or elements of the bottle 101 and respectively of the preform 101P for producing the bottle.

As best seen in Fig. 3, where the bottle neck 101A is shown with the cap 103 removed from it, the bottle neck 101A has an external thread 105, formed on the external surface 101Z of the bottle neck 101A, i.e. a thread external 105 is formed by the external surface 101Z of the bottle neck 101A. The maximum diameter of the external surface 101Z of the bottle neck 101A, i.e. the external diameter of the thread 105, is indicated with DM (Fig. 2).

The neck 101A of the bottle defines at one end of it a mouth, or mouth opening 101C (Fig.3) of the bottle 101. An annular shoulder 101X is provided at the opposite end of the neck 101A of the bottle (Figs.2 and 6). The annular shoulder 101X is spaced from the mouth 101C. The threaded outer surface 101Z extends between the mouth 101C and the shoulder 101X. The annular shoulder 101X projects radially inwards, from the outer surface 101Z towards an axis A-A of the bottle neck 101A. If the bottle 101 has an axial-symmetrical shape, the axis A-A of the bottle neck 101A coincides with the symmetry axis of the bottle. The annular shoulder 101X has a minimum internal diameter Dm (Fig. 2). In some embodiments the annular shoulder 101X has a radial dimension (given by the difference between the maximum diameter and the minimum diameter of the shoulder 101X) which can be between about 1.5 and about 4 mm, for example between about 2 mm and 3.5 mm.

The annular shoulder 101X can have a flat, i.e. flat surface, which can be approximately orthogonal to the axis A-A of the bottle neck 101A.

In some embodiments, the external surface 101Z of the bottle neck 101A can be provided with an annular edge 102 that surrounds the annular shoulder 101X and forms an extension of its external radial dimension. In some embodiments, the annular edge 102 has an outer diameter D102 (Fig. 12) which is no greater than the major diameter DM of the outer surface 101Z, i.e., no greater than the outer diameter of the outer thread 105. In some embodiments, the annular edge (102) has a lower surface which forms a flat extension of the shoulder 101X as best seen in Fig. 17.

In some embodiments, the diameter DM may be between about 22 mm and about 28 mm, for example between about 23 and about 26 mm. In some embodiments, the diameter Dm may range from about 15 mm to about 25 mm, for example from about 17 mm to about 23 mm, for example from about 20 mm.

The height H1 (Fig.2) of the cylindrical terminal portion of the bottle neck 101A can be between about 6 mm and about 10 mm, preferably between about 6 mm and about 8 mm, for example around 7 mm. The height H1 is the distance between the flat surface of the annular shoulder 101X and the mouth 101C of the bottle.

According to some embodiments, radial projections 104 can be provided along the shoulder 101X of the bottle neck 101A and project radially outward therefrom. Each radial projection 104 can extend from an internal diameter R1 (Fig.4) to an external diameter (R2). The radial dimension of each projection 104 is therefore R1-R2. The projections 104 can be spaced from each other at regular angular intervals, i.e. with a constant angular pitch. By way of example (see Fig. 15) five projections 104 can be provided, arranged at a regular interval of 72 °. In other embodiments, a different number of protrusions 104 may be provided. Preferably there are at least two protrusions 104, preferably at least three protrusions 104, and preferably fewer than eight protrusions 104, for example five or six protrusions 104.

If the bottle neck 101A is provided with an annular rim 102, as shown in the accompanying drawings, the projections 104 may extend radially outward from an outer annular surface of the rim 102. The projections 104 may have a radial extension L104 (Fig.4) comprised between about 0.8 mm and about 2 mm, preferably between about 0.9 mm and about 1.5 mm.

In some embodiments, the radial extent of the projections 104 is less than the radial extent of the outer surface 101Z, including the outer thread 105, i.e. the radial extent of the projections 104 is equal to or less than the outer radius (DM / 2) of the external thread 105, so that the protrusions 104 are contained within a theoretical cylindrical surface that surrounds the external thread 105. In other embodiments, the protrusions 104 have a radial extension greater than the external diameter of the external thread 105. For example, each projection 104 may extend from about 0.1 to about 0.5 mm beyond the theoretical cylindrical surface which encloses the external thread 105 and having a diameter DM.

As better visible in Figs. 4 and 7, in the embodiments described here the projections 104 have an asymmetrical shape in a sectional view according to a plane orthogonal to the axis A-A of the bottle 101. In this cross-sectional view, each projection 104 it preferably has a first flank 104A and a second flank 104B both extending radially outwards from the annular edge 102 (or in general from the outer surface 101Z) and extending towards an outer edge 104C.

Each side 104A can have a rounded outer corner where the side 104A joins the outer edge 104C. Each side 104B can have a rounded corner with a smaller radius of curvature, that is, more acute than the angle at the outer end of the side 104A, where the side 104B joins the outer edge 104C. In some embodiments, each of said two flanks 104A and 104B can form an angle α with a radial direction (see in particular Fig.7). The two angles can be equal to each other, but they can be oriented in opposite directions with respect to a straight radial line that passes through the internal terminal radial point of the flank, as shown in Fig. 7.

In some embodiments, the angle α can be between about 15 ° and about 28 °, preferably between about 18 ° and about 24 °, more preferably between about 20 ° and about 24 °.

In other embodiments, the two sides of the same projection 104 can form different angles with the radial direction. For example, the side 104A, with a rounded corner, can form a greater angle with the radial direction than the side 104B.

As better visible in Figs.4 and 7, in some embodiments the two sides 104A, 104B of each protrusion 104 converge in an outward radial direction, i.e. from the inner radius R1 to the outer radius R2.

Each protrusion can have an inclined upper surface 104D (see Figs. 5 and 6), which is inclined with respect to a plane orthogonal to the axis A-A of the bottle. Each sloped top surface 104D can be sloped downward toward the bottom of the bottle (not shown).

The cap 103 can have an approximately axial-symmetrical shape with an axis A-A coinciding with the axis A-A of the bottle 101 when the cap 103 is screwed onto the neck 101A of the bottle. The cap 103 may comprise a lateral circumferential wall 107 which extends from a circular lower end edge 109 to a front or upper wall 111 of the cap 103. The lateral circumferential wall 107 has an outer surface 107A and an inner surface 107B (Fig. .8).

In some embodiments, an internal thread 113 is provided on the internal surface 107B. The internal thread 113 can be configured to cooperate with the external thread 105 provided on the bottle neck 101A so that the cap 103 can be screwed onto the bottle neck 101A. and unscrewed from it.

The cap 103 can have an axial dimension, i.e. a height H2 (see Fig. 2), which can be comprised between about 6 mm and about 10 mm, preferably between about 7 mm and about 8 mm. The height H2 of the cap 103 can advantageously be such that, when the cap 103 is screwed onto the bottle 101, the lower edge 109 of the cap 103 is positioned approximately in correspondence with the shoulder 101X of the neck 101A of the bottle, and preferably between the flat surface shoulder 101X and external thread 105 (Fig. 6).

In some embodiments (see Figs. 2, 6), in the fully screwed position the lower edge 109 of the cap 103 can be positioned at the annular edge 102 or immediately above said annular edge 102.

In some embodiments, the cap 103 is provided with a ring 115, in the form of a thin wall or approximately cylindrical lip 115 which surrounds the A-A axis of the cap 103. The cylindrical lip 115 protrudes from the lower edge 109 of the cap 103 and it extends in an axial direction (i.e. parallel to the A-A axis of the cap 103) away from the lower edge 109.

The cylindrical lip 115 can have a thickness (i.e. a dimension in the radial direction, orthogonal to the axis A-A of the cap), which is substantially less than the thickness of the lateral circumferential wall 107 of the cap 103. For example, the cylindrical lip 115 can have a thickness comprised between about 0.1 mm and about 1 mm, preferably between about 0.2 mm and about 0.5 mm. In some embodiments, the side wall 107 of the cap 7 can be for example 5 to 10 times thicker than the cylindrical lip 115.

In some embodiments, the cylinder lip 115 can have a height H115 (Fig. 5), i.e. a dimension in the axial direction, such that the total height H3 (Fig. 2) of the cap 103, including the cylindrical lip 115 , can be between about 8 mm and about 12 mm. In some embodiments, the height H3 can be between about 9 mm and about 11 mm, for example between about 9 mm and about 10 mm.

In some embodiments, the thickness of the cylindrical ring or lip 115 is such that the cylindrical lip can be easily torn off by cooperation with the projections 104, as will be described in greater detail below.

The cylindrical lip 115 can have a plurality of openings 117 arranged around its circumferential development. The openings 117 may be in the form of slots, notches or cuts extending across the entire thickness (radial dimension) of the cylindrical lip 115. Each opening 117 may have a first dimension in the circumferential direction (circumferential dimension) and a second dimension in the axial direction (axial dimension). In some embodiments, the circumferential dimension may be larger than the axial dimension. For example, the circumferential dimension can be at least double the axial dimension, preferably at least three times, for example at least four times the axial dimension.

Hereinafter the openings 117 will be referred to as slots 117. The term slot as used herein can be understood as an opening having a larger circumferential dimension and a smaller axial dimension, that is, having a circumferential extension around the axis A-A which is greater , for example at least three times greater, than the extension in the axial direction.

In some embodiments, the axial dimension (height H117, Fig. 5) of each slot 117 is approximately 2/3 of the axial dimension (height H115, Fig. 5) of the cylindrical lip 115, i.e. H117 <2 * H115 / 3. Preferably the axial dimension H117 of each slot 117 is equal to or less than half of the axial dimension H115 of the cylindrical lip, i.e. H117 <H115 / 2. In embodiments described herein, in the cylindrical lip 115 there is a number of slots 117 equal to the number of projections 104 around the bottle neck 101A. When the cap 103 is screwed onto the bottle 101, each protrusion 104 engages in one of the slots 117. The number of slots 117 can for example be between 2 and 10, preferably between 2 and 8, more preferably between 3 and 5.; Each slot has a circumferential dimension L117 (see Fig. 7). The distance between two slots 117 arranged sequentially is indicated with D117 (Fig. 4). The distance D117 is greater than the circumferential dimension L117. Preferably the distance D117 is at least double, preferably three times the circumferential dimension L117. The sum of the circumferential dimension L117 and the slots 117 is given by LT117 = n * L117, where "n" is the total number of slots 117. In embodiments described here, the sum LT117 is less than about 50% of the circumferential extension of the cylindrical lip 115, preferably less than about 30%, more preferably less than about 25% of the circumferential extent of the cylindrical lip 115.

As will become clearer from the following description of the operation of the bottle and cap system described here, contrary to the circlips of the current art, the circlip formed by the cylindrical lip 115 does not detach from the side wall 107 of the cap 103. Rather , it will tear in correspondence of some cracks 117 but the plastic material of which the cylindrical lip 115 is made will remain attached to the cap and will be removed together with it.

Similarly, the circumferential distance between two sequentially arranged projections 104 is greater than the circumferential dimension of each projection 104. Preferably the distance between adjacent projections 104 is at least double, preferably at least three times the circumferential dimension of each projection 104. The sum of the dimension circumferential of the projections 104 may preferably be less than 50% of the circumferential development of the edge 102, preferably less than about 30%, more preferably less than about 25% of the circumferential development of the edge 102. In currently preferred embodiments, the slots 117 are disposed in proximity to the lower edge 109 of the circumferential side wall 107. In some embodiments, each slot 117 is disposed just along the junction between the cylindrical lip 115 and the lower edge 109 of the lateral circumferential wall 107, as may best be observed in Fi days 5 and 8.

The asymmetrical shape of the sides 104A and 104B of the projections 104 is such that the cap 103 can be screwed onto the neck 101A of the bottle without tearing or damaging the cylindrical lip 115. The mutual position of the sides 104A, 104B is such that when the cap 103 is screwed onto the bottle neck 101A and the cylindrical ring or lip 115 reaches the protrusions 104, the cylindrical lip 115 will initially slide on the inclined surface 104D of the protrusions 104 and then move with its surface facing radially inward on the outer edge 104C of the projections 104, in the direction represented by the arrow f115 (Fig. 4). The cylindrical lip 115 will thus be pushed radially outwards from the rounded side 104A, so that the cap 103 can be completely screwed onto the neck 101A of the bottle, until the projection 104 penetrates the respective slot 117. The inclined upper surface 104D facilitates the sliding and the outward radial deformation of the cylindrical lip 115 during the screwing of the cap 103 onto the neck 101A of the bottle.

When the cap 103 is unscrewed from the bottle 101, with a rotation in the opposite direction to the arrow f115 (Fig. 4), the sides 104B of the projections 104 will abut against the edge of the respective slot 117 in which the projection 104 is engaged, preventing in this way the rotation of the cap 103. Unscrewing is possible only if the applied torque exceeds the breaking load of the cylindrical lip 115, causing it to break at each slot 117.

The cylindrical lip 115 is therefore configured as an element of a security seal, i.e. as a security ring. The integrity of the cylindrical lip 115 demonstrates the integrity of the bottle. As soon as someone attempts to open the bottle, the attempt is evidenced by the fact that the cylindrical lip 115 is torn.

The shoulder 101X, which extends radially inward from the outer surface 101Z of the bottle neck 101A, provides an annular shoulder for guiding the bottle in a filling and packaging system. Since the shoulder 101X extends radially inward from the outer surface 101Z on which the outer thread 105 of the bottle neck 101A is formed, the annular shoulder 101X does not increase the amount of plastic required to manufacture the bottle 101. A annular shoulder on a bottle 101 in which the amount of plastic is minimized.

Furthermore, the rim 102 (if provided) and the projections 104 have a limited volume, so that said components do not contribute significantly to the total mass of plastic required to produce the bottle 101.

The shape of the cap 103, with the cylindrical lip 115 forming the safety ring, minimizes the amount of plastic needed to mold the cap. The overall height H3 can be lower than the height of the caps of the prior art. Furthermore, the shape of the safety ring constituted by the cylindrical lip 115 is such that after tearing the ring remains attached to the cap 103 and is neither dispersed into the environment nor remains attached to the bottle 101, which could cause difficulties in bottle recycling.

Claims (15)

"BOTTLE AND SCREW CAP FOR SAID BOTTLE" Claims 1. A bottle (101) comprising: - a body (101B); - a neck (101A) of the bottle forming a mouth (101C) of the bottle and having an external surface (101Z) forming an external thread (105); - an annular shoulder (10 IX) between the body (101B) and the external thread (105), said annular shoulder (101X) extending radially inwards, from the external surface (101Z) of the neck (101A) of the bottle towards a axis (A-A) of the bottle neck; characterized in that it further comprises a series of radial projections (104) arranged on the external surface (101Z) of the neck (101A) of the bottle, between the external thread (105) and the annular shoulder (101X), and extending radially towards the external from the external surface (101Z). The bottle of claim 1, wherein the radial projections (104) are disposed along the annular shoulder (101X) and adjacent thereto. The bottle of claim 1 or 2, wherein the radial projections (104) are distributed with a constant angular pitch around the axis (A-A) of the neck (101A) of the bottle. The bottle of claim 1 or 2 or 3, wherein each radial projection (104) has two asymmetrical radial sides (104A, 104B). The bottle of one or more of the preceding claims, wherein each radial projection (104) has an inclined upper surface (104D), which extends radially outward and which is inclined from the mouth (10 IX) towards the body (101B) of the bottle (101). The bottle of one or more of the preceding claims, further comprising an annular rim (102) extending from the outer surface (101X), and in which the radial projections (104) are arranged on the annular rim (102) and project from it radially outwards. The bottle of claim 6, wherein the annular rim (102) has an outer diameter (D102) which is equal to or less than the outer diameter (DM) of the outer thread (105). The bottle of claim 6 or 7, wherein the annular edge (102) is disposed along the annular shoulder (101X). 9. The bottle of one or more of claims 6 to 8, in which the annular edge (102) forms a radial extension of the annular shoulder (101X). 10. A screw cap (103) for a bottle (101), comprising a lateral circumferential wall (107) extending around an axis (A-A) of the cap (103) from an upper wall (111) to a lower edge circular (109), and a security seal; wherein the lateral circumferential wall has an inner surface (107B) and an outer surface (107A); wherein the internal surface (107B) forms an internal thread (113); characterized in that said security seal comprises a cylindrical lip (115) formed along the lower edge (109) and extending axially therefrom; wherein openings (115) are provided along the cylindrical lip (115). The screw cap of claim 10, wherein sequentially arranged openings are spaced apart from each other by a greater distance than the circumferential dimension of an opening. The screw cap of claim 11, wherein the sum of the circumferential development of said openings (117) is less than about 50% of the circumferential development of said cylindrical lip (115), preferably less than about 30%, plus preferably less than about 25% of the circumferential extent of the cylindrical lip (115). The screw cap of one or more of claims 10 to 13, wherein the openings (117) are formed by slots extending in a circumferential direction around the axis (A-A) of the cap (103). The screw cap of one or more of claims 10 to 13, wherein each opening (117) is arranged near the lower edge (109) of the circumferential side wall (107), preferably at a junction between the cylindrical lip (115) and the lower edge (109) of the lateral circumferential wall (107). A system comprising a bottle (101) according to one or more of claims 1 to 9 and a screw cap (103) according to one or more of claims 10 to 14, wherein the radial projections (104) of the bottle are adapted to engage in the openings (117) of the plug (103).