The present invention relates to the technical sector of container caps. More specifically, the present invention relates to a screw cap for closing a container, as well as a closing device intended for a container and comprising such screw cap, as well as a container comprising such screw cap. In particular, the present invention applies, preferably though non-exclusively, to the sector of containers for any field, both commercial and not, such as bottles or tin containers or containers made of multilayer material for packaging foodstuffs, provided with cap-closable openings.

In the field of food packaging, which will be referred to hereinafter without losing generality, a container is provided with a device for opening and closing the container. This device makes it possible to keep the food product contained in the container in a predetermined condition, at least until it is first opened, and then to easily access the product as required or desired by the user.

In particular, screw caps provided with an inner thread, which, by means of being screwed- unscrewed on a suitably counter-threaded neck, determine the opening and closing of the container itself, are widespread. In this sector, screw caps generally have an outer diameter of between 20 mm and 36 mm, such as of 25 mm, or 28 mm, or 30 mm.

In the present description as well as in the accompanying claims, certain terms and expressions are deemed to have, unless otherwise expressly indicated, the meaning given in the following definitions.

The term “parallel” refers to a substantial parallelism between two elements, comprising both the ideal case in which these elements are arranged in relation to each other so as to form a null angle, and more frequent cases in which the two elements are arranged in relation to each other so as to form an angle that is not null but still negligible or irrelevant for the purposes of the present solution.

Two elements are considered as “consecutive” when they are placed one after the other without any further element being placed between them.

The term “tubular” means having a cylindrical, conical or elongated truncated-cone shape and hollow inside.

The “inner surface” of a hollow element in relation to a longitudinal axis refers to the side of the element facing the longitudinal axis. The “outer surface” of the same hollow element is defined as the side of the element furthest from the longitudinal axis and facing the outward direction from it.

Given a longitudinal axis, the term “cross-section” of an element means a section of that element defined along a plane perpendicular to that longitudinal axis, while the term “longitudinal section” of an element means a section of that element defined along a plane parallel to the longitudinal axis.

The Applicant has verified by means of a targeted research that users frequently complain about an unpleasant and sometimes painful sensation on their fingers when screwing and unscrewing the screw cap.

The Applicant therefore felt the need to make it more comfortable and safer for the user to manipulate the cap, in order to further ease unscrewing and screwing the cap on the respective neck.

The Applicant firstly noted that the problem consisted in the geometric shape of the outer side surface of the screw cap. Such surface generally comprises a plurality of ribs or angular reliefs to make it possible for the user, who wishes to open or close the container, to firmly grip and rotate the cap. In particular the user grabs the cap between thumb and forefinger and exerts a force to rotate it about the neck, pressing on the outer side surface of the cap. This grip causes the plurality of reliefs on the outer side surface to adhere and push against the fingertips of the thumb and forefinger, causing the aforementioned unpleasant sensation. The user discomfort is also greater when the cap is firmly screwed onto the respective neck and, despite the force exerted by the user, fingers slip on the cap and the edges of the reliefs scratch, and in some cases, injure the user.

In an attempt to solve this drawback, the Applicant firstly attempted to thicken the reliefs on the outer side surface of the cap so as to reduce the gap between two successive reliefs and simulate a virtual surface with an overall circular shape. However, the Applicant ascertained that this solution had several limitations that hindered the effective implementation thereof. In particular, the Applicant ascertained that as the number of reliefs on the outer side surface of the cap increased, the user's grip became less firm, thus the user had to exert a greater force to rotate the cap and the fingers still kept on sliding, in an unpleasant way, on the outer side surface of the cap.

The Applicant therefore realised that the angular shape of the reliefs was the main cause of the user's discomfort and scratches and this could be avoided by suitably shaping the reliefs.

The Applicant finally found that providing a suitable number of ergonomically shaped reliefs on the outer side surface of the cap makes it possible for the user to use a reduced force to firmly manipulate the cap and without being annoyed or injured by the grip.

Thus, the present invention, in a first aspect thereof, relates to a cap for closing a container. Preferably the cap comprises a side wall that defines a longitudinal axis.

Preferably the side wall includes two ends. Preferably said ends are opposed to each other along said longitudinal axis.

Preferably the side wall includes an inner side surface extending between said two ends. Preferably the inner side surface is provided with a coupling system, in particular to removably couple said cap to said container.

Preferably the side wall includes an outer side surface extending between said two ends. Preferably said outer side surface is at a greater distance from said longitudinal axis compared to said inner side surface. Preferably said outer side surface comprises a plurality of gripping surfaces. Preferably said outer side surface comprises a plurality of intermediate surfaces. Preferably, said gripping surfaces are located at a greater distance from said longitudinal axis compared to said intermediate surfaces. Preferably said gripping surfaces are intended to receive a user’s fingers.

Preferably said outer side surface is provided with at least 48 gripping elements. Preferably said gripping elements are radially distributed about said longitudinal axis.

Preferably said gripping elements each comprise one of said gripping surfaces. Preferably, each gripping surface has respective circular-arc-shaped cross-sections along said longitudinal axis. Preferably, said gripping elements radially protrude from said intermediate surfaces.

Thanks to the large number of gripping elements, equal to or higher than 48, which are radially distributed about the longitudinal axis so as to reduce the gap between two successive gripping elements, and which comprise respective gripping surfaces having circular-arc-shaped crosssections, the user's fingers are in contact with a virtual surface having an overall circular shape. In addition, the rounded shape of the gripping elements given by their circular-arc-shaped crosssection allows the user's fingertips to better adhere to the gripping element, without exerting an excessive force, and overcomes the unpleasant sensation on the user's fingers.

The present invention, in a second aspect, relates to a closing device for a container.

Preferably said closing device comprises a neck intended to be connected to said container. Preferably said neck has a spouting wall with an outer coupling surface.

Preferably said closing device comprises a cap as described above.

Preferably the inner side surface of said cap is intended to removably couple with the outer coupling surface of said neck.

The present invention, in a third aspect, relates to a container.

Preferably said container comprises a neck. Preferably said neck has a spouting wall with an outer coupling surface.

Preferably said container comprises a cap as described above.

In at least one of the aforesaid aspects, the present invention may also have at least one of the preferred characteristics set forth hereinafter.

Preferably, said gripping surfaces are radially distributed about said longitudinal axis. Preferably said intermediate surfaces are radially distributed about said longitudinal axis. Preferably, each of said gripping surfaces is adjacent to one of said intermediate surfaces. Preferably, each of said intermediate surfaces is adjacent to one of said gripping surfaces. Preferably, said gripping surfaces are equal in number to said intermediate surfaces.

Preferably, each intermediate surface has respective circular-arc-shaped cross-sections along said longitudinal axis.

Preferably, said gripping elements radially protrude from said intermediate surfaces by a length of between 0.3 mm and 0.5 mm, preferably of 0.35 mm.

Preferably said side wall is tubular. In a first embodiment, said wall has a constant longitudinal section. In an alternative embodiment, said tubular side wall has a converging longitudinal section. In one or more embodiments, said ends are circular. In one or more embodiments, said ends are centred on said longitudinal axis.

In one or more embodiments, said gripping elements are between 48 and 96 in number.

In one or more embodiments, said outer side surface is provided with 48 gripping elements.

In one or more embodiments, at least one of said gripping elements extends between said two ends. In one or more embodiments, at least one of said gripping elements comprises a gripping surface with circular-arc-shaped sections all having the same constant radius along said longitudinal axis. In one or more embodiments, at least one of said gripping elements comprises a gripping surface with circular-arc-shaped sections with a variable circumference along said longitudinal axis.

The selection of gripping elements with circular-arc-shaped sections with a constant or variable circumference along the longitudinal axis makes it possible to define differently shaped side surfaces, with a particularly attractive appearance for the consumer, without the cap losing functionality.

In one or more embodiments, said circular arc of the cross-sections of said gripping surfaces is subtended by a respective angle at the centre between 150° and 190°, preferably between 165° and 175°, preferably of 170°. Preferably the angles at the centre of the circular-arc-shaped crosssections of said gripping surfaces are equal to each other.

In one or more embodiments, said circular arc of the cross sections of said gripping surfaces has a radius of between 0.3 mm and 0.5 mm, preferably between 0.35 mm and 0.45 mm, preferably of 0.39 mm. Preferably the radii of the circular arc cross-sections of said gripping surfaces are equal to each other.

In one or more embodiments, said intermediate surfaces have, along said longitudinal axis, respective circular-arc-shaped cross-sections subtended by a respective angle at the centre between 2° and 6°, preferably between 3° and 4°. Preferably the angles at the centre of the arc-shaped crosssections of said intermediate surfaces are equal to each other.

In one or more embodiments, said circular arc of the cross sections of said intermediate surfaces has a radius of between 10 mm and 18 mm, preferably between 12 mm and 15 mm, preferably of 14 mm. Preferably, the radii of the arc-shaped cross-sections of said intermediate surfaces are constant and equal to each other. Preferably said circular arc is centred on said longitudinal axis.

In one or more embodiments, said gripping elements are uniformly distributed about said longitudinal axis.

In one or more embodiments, said gripping elements are grouped into gripping assemblies. Preferably, two consecutive gripping elements of a gripping assembly have a shorter distance than a distance between consecutive gripping elements belonging one to a first gripping assembly and the other to a second gripping assembly that is consecutive to the first gripping assembly.

Preferably each gripping assembly includes three gripping elements.

Preferably said gripping elements are substantially parallel to said longitudinal axis.

Similarly, these gripping elements are preferably arranged in a direction other than a direction parallel to said longitudinal axis.

Preferably said coupling system comprises a threaded element. Preferably said threaded element is intended to couple said cap to said container in rotation about said longitudinal axis.

In one or more embodiments, said cap comprises locking means to limit said rotation.

In one or more embodiments, said cap comprises tamper-evident means to signal improper use of the cap. Preferably such tamper-evident means comprise a first-opening seal.

In one or more embodiments, said cap comprises an upper wall.

In one or more embodiments, said upper wall is circular.

In one or more embodiments, said upper wall is connected to said side wall, in particular at one of said two ends.

In one or more embodiments, said upper wall is provided with auxiliary elements having an elongated shape in the direction of a respective secondary axis parallel to said upper wall. Preferably said auxiliary elements each comprising an auxiliary gripping surface, said auxiliary gripping surfaces having along said secondary axis respective circular-arc-shaped longitudinal sections, in particular each of said longitudinal sections being defined in a plane parallel to said longitudinal axis and orthogonal to the respective secondary axis. Preferably, these auxiliary elements are equal in number to said gripping elements. Preferably each of said auxiliary elements joins with only one of said gripping elements.

Preferably, said secondary axes of said auxiliary elements are each oriented in their own direction deviating by a predetermined angle from the radial direction in relation to the longitudinal axis.

Thanks to the presence of the auxiliary elements of the upper wall, which join the gripping elements and also have a rounded shape given by their longitudinal circular-arc-shaped section, the user exerts an effective and comfortable grip even when his or her fingers come into partial contact with the upper wall. Furthermore, the orientation of the secondary axes and thus of the auxiliary elements in directions deviating by a predetermined angle from the radial direction in relation to the longitudinal axis, in particular by a positive angle in the rotation direction for opening the cap, allows the user to exert an even more effective grip on the cap itself.

In one or more embodiments said upper wall is pivotably connected to said side wall about an axis of rotation perpendicular to the longitudinal axis, preferably at a joint area on one of said two ends. Preferably said upper wall is movable, in particular between a closing position wherein said upper wall totally overlaps said side wall and an opening position wherein said upper wall is connected to said side wall only at said joint area.

Such cap, with the upper wall pivotable in relation to the side wall, may be used effectively in the closing devices joined with a perforated opening, so-called tethered caps, due to the fact that the cap can always be kept connected to the neck of the closing device itself. In a closing device with a perforated opening, when first used, the cap is capable of performing a rotation, in relation to the neck, about a longitudinal axis defined by the closing device itself, in order to actuate a cutting element coupled to the neck and perforate the protective membrane of the container to which the closing device is connected. In particular, the rotation of the cap in relation to the neck about the longitudinal axis is limited to a certain angle, e.g. less than the round angle, e.g. between 90° and 270°. Precisely due to the fact that the cap comprises an upper wall pivotable in relation to the side wall, it is therefore advantageously possible to provide that this cap remains connected to the neck and that access to the container is regulated by the position of the upper wall of the cap. In greater detail, in the closing position, the upper wall is kept overlapping the side wall so as to close the passage through the latter and prevent access to the container; with a simple rotation about the axis of rotation perpendicular to the longitudinal axis, the upper wall may be brought from the closing position to the opening position in which it is partially separated from the side wall, so as to allow passage through the side wall itself and thus access to the container. This embodiment therefore removes the risk of the cap being dispersed into the environment and helps to reduce the volume of waste and the impact on climate change.

In one or more embodiments, said cap is made of at least partially recycled material, preferably entirely recycled.

In one or more embodiments, said cap is made of at least partially recyclable material, preferably fully recyclable.

In one or more embodiments, said cap is made of polymer.

Further characteristics and advantages of the invention will become more evident from the following detailed description of a preferred embodiment, shown merely by way of non-limiting example, with reference to the attached drawings, wherein:

- Figure 1 is a perspective view from above of a cap according to the present invention.

- Figure 2 is a perspective view from below of the cap of Figure 1;

- Figure 3 is a partial view from above of the cap of Figure 1.

A cap 1 for closing a container, not illustrated, is shown in the Figures.

The cap 1 comprises a tubular-shaped side wall 2 defining a longitudinal axis X and including two circular ends 21, 22, centred on said longitudinal axis X and opposed to each other, an inner side surface 25 and an outer side surface 23 intended to be grabbed by the user.

The inner side surface 25 and outer side surface 23 extend between the two ends 21, 22 and the outer side surface 23 is placed at a greater distance from the longitudinal axis X compared to said inner side surface 25.

The inner side surface 25 is provided with a coupling system 26, e.g. a threaded element, to removably couple the cap 1 to the container. In particular, the threaded element of the coupling system 26 determines the coupling of the cap 1 to the container by means of a screwing rotation about the longitudinal axis X and, similarly, the removal of the cap 1 from the container by means of an unscrewing rotation about the same longitudinal axis X.

The outer side surface 23 comprises a plurality of gripping surfaces 241 and a plurality of intermediate surfaces 242. The gripping surfaces 241 are placed at a greater distance from the longitudinal axis X compared to the intermediate surfaces 242. With reference to the attached figures, each gripping surface is adjacent to an intermediate surface and each intermediate surface is adjacent to a gripping surface, resulting in a number of gripping surfaces equal to the intermediate surfaces.

The outer side surface 23 is provided with at least 48 gripping elements 24 radially and uniformly distributed about the longitudinal axis X, and parallel to the latter.

Each one of the gripping elements 24 comprises its own gripping surface 241. Along the longitudinal axis X, the gripping surface 241 of each gripping element 24 has circular-arc-shaped sections all having a same constant radius. Thus, the gripping elements 24 radially protrude from the intermediate surfaces 242.

The cap 1 further comprises an upper wall 3, in particular circular, connected to the side wall 2 at one of said two circular ends 21, 22, and tamper-evident means 4 including a first-opening seal connected to the other of said two ends 21, 22. In particular, this first-opening seal is a ring attached to the respective one of two ends 21, 22 by means of frangible bridges; when the cap is first used, the user applies an initial force to break the frangible bridges and permanently separate the tamper- evident ring from the cap.

The Applicant has verified that the 48 gripping elements radially distributed over the entire outer side surface of the cap and with gripping surfaces having circular-arc-shaped sections, i.e. rounded, result in a comfortable sensation on the user's fingers.

Experiments conducted in-house by the Applicant and reported hereinafter have also shown that the cap according to the present invention allows the user's fingertips to better adhere to the gripping element, and allows the user to exert a reduced torsional force.

The table reported hereinafter compares the results of the measurements carried out by the Applicant on the caps of two different types: ten caps of a first type called TYPE A, which have 24 gripping elements of any type; ten caps of a second type called TYPE B, which have 48 gripping elements according to the present invention, in particular with the circular arc of the cross-sections of the respective gripping surfaces subtended by an angle at the centre of 170° and having a radius of 0.39 mm. Both the TYPE A- and TYPE B-caps have an outer diameter of 28 mm. Each cap was applied to a torsiometer to measure the torsion force required to rotate the cap in two different situations: in the first use, i.e. when the frangible bridges are intact and the first-opening seal is connected to the cap; in the second use, i.e. when the frangible bridges are broken, the first-opening seal is separated from the cap and the cap has to overcome only the friction force on the neck of the container.

The table reports the average and the standard deviation on ten TYPE A-caps and ten TYPE B- caps.

The results show that the force required to rotate the type B-cap according to the present invention is less than the force required to rotate the TYPE A-cap, both in the first and second use.