Description

A Capsule with a Reservoir for Substances to be Mixed with Liquids at

Time of Use.

Technical Field

The invention relates to a capsule with a reservoir for substances to be mixed with liquids at time of use.

Background Art

The prior art includes packages, both single-dose and pluri-dose, which comprise a container, containing a liquid, on which a closure capsule is mounted, of various types. The capsule internally affords a reservoir having a breakable bottom, internally of which reservoir a cutting element is located, which causes breakage of the breakable bottom. The reservoir contains a substance, in general powders or granules, which when the breakable bottom is ruptured, fall into the container and dissolve in the -liquid contained in the container. Independently of how the capsule and reservoir are made, the breakable bottom of the tank, normally made of a plastic material, is connected to the remaining part of the reservoir by a circumferential line having a much-reduced thickness so as to be easily cuttable by exerting a slight pressure on the cutting element. By way of example, while the thickness of the reservoir walls is usually comprised between 1 and 2 millimetres, the circumferential line long which the cut is made is of a thickness which, in order to enable an easy cutting operation, does not generally exceed 0.15 mm and in some cases is even less.

The substances contained in the reservoir, which are soluble in the liquid contained in the container and are dissolved in the liquid at moment of use, are generally sensitive to moisture, due both to their physical nature (they can agglomerate in an undesirable way) and to problems of a chemical nature (their properties can change). The problems of a chemical nature are often the reason why these preparations involve mixing of the substance into the solvent only at moment of use.

The materials of which the reservoirs containing the substances are made are by their nature permeable to humidity, even though to a small extent; this permeability does not lead to appreciable consequences in the zones of the reservoirs that are at highest risk inasmuch as a very long time is needed for the humidity to migrate into the reservoir. The humidity-migratory phenomenon is however very relevant in proximity of the circumferential line of the reservoir along which the cut is made, as the thickness of the circumferential line is extremely small and the migration time for the humidity across the line is considerably less than in the rest of the reservoir walls. This migratory phenomenon leads, in relatively short times, to deterioration of the chemical-physical characteristics of the substance contained in the reservoir, or in at least a part thereof. Attempts have been made to obviate the above drawback by making reservoirs out of plastic materials having a lower permeability to moisture. This solution has not succeeded in eliminating the problem, only slowing its evolution, and what is more, the materials used have characteristics which make them very difficult to cut with the cutters normally usable; for this reason the use of these materials has been abandoned.

A further solution applied has been to insert a greater-than-necessary quantity of substance into the reservoir; in this way, as the deterioration of the

substance is progressive, even if a part deteriorates there still remains enough, and for a sufficiently long time, for the aims of the container to be achieved. This is an expensive solution which is also imprecise with regard to the composition required for the final product. A further solution has been to indicate a use-by date for the container which takes the factor of moisture absorption across the circumferential cutting line of the reservoir into consideration - a date which is much more limited with respect to the actual product decay times. This solution too is rather expensive. A further solution adopted, described in international application PCT/IT2005/000405 by the same applicant, is to use a moisture barrier element externally connected to the bottom zone of the reservoir and cuttable together with the bottom of the reservoir. This solution too implicates an increase, however slight, in production costs. The aim of the present invention is to obviate the drawbacks by providing a capsule which can perform the functions of the known capsules with reservoirs and which at the same time offers long impermeability times against moisture. A further advantage of the present invention is that it provides a capsule with a reservoir which is very slow to become permeable both when the capsule is free-standing (it is a single product) and when it is inserted on the container to constitute the definitive package. Disclosure of Invention Further characteristics and advantages of the present invention will better emerge from the detailed description that follows of an embodiment of the capsule with a reservoir of the invention, illustrated purely by way of non- limiting example in the accompanying figures of the drawings, in which:

Figure 1 is a section in vertical elevation of the capsule of the invention, in a closed position, mounted on a container;

Figure 2 is a section in vertical elevation of the capsule in an open position; Figure 3 is a section in vertical elevation of the capsule in a closed position; Figure 4 is a perspective view from below of the cap of the capsule of the invention.

In the figures of the drawings, 1 denotes a container, a mouth 2 of which is closed by a capsule 3 of the type of the invention. A reservoir 8 is associated to the capsule 3 in a way that will be more fully described herein below, the reservoir 8 being able to contain substances S, in particular powders or granules. This type of capsule, as in known-type-capsules, is normally used for single-dose containers or multi-dose containers by means of which a solution of a substance contained in the reservoir is obtained which, immediately before use, is made to fall, normally by force of gravity, into the liquid, generally a solvent, contained in the container.

The capsule of the invention comprises a cap 4 for closing the mouth 2 of the container, the cap 4 preferably being fixed to the mouth 2 of the container 1 by means of a threaded coupling; the connection is removable so as to enable the container to be opened once the liquid-substance solution has been obtained.

Various security systems can be applied to the capsule, such as for example the security ring 4a, connected to the cap 4 by easy-break ribs which are torn at first opening of the container. Covering hoods can also be applied to cover the whole capsule and safeguard it from external agents such as power, dirt and the like. These elements (security systems and covering hoods) are however all of known type.

The reservoir 8 has a substantially cylindrical shape and exhibits an open end 8a. The other end of the reservoir is closed by an upper wall. The cap 4 comprises a conduit 7 which is substantially cylindrical, is open on the external part of the cap and is coaxial of the cap 4. The conduit 7 is destined to house the open end 8 a of the reservoir which terminates with the open end; the reservoir is inserted in the conduit such that the open end is facing towards the inside of the container.

The size of the conduit and the reservoir are such that when the reservoir is inserted in the conduit 7, the external wall of the reservoir closes the conduit 7, sealing it from the outside environment. In other words, the reservoir is inserted in the conduit 7 with a slight interference, in such a way that the external surface of the reservoir and the internal surface of the conduit are in contact at one or more circumferential rings or on a cylindrical surface which guarantees the seal. The capsule of the invention further comprises an obturator 5 which is solidly constrained to the cap 4 and which is sealedly associable to the open end 8a of the reservoir in order to close it. The characteristic the obturator 5 must have is that of being extractable from the open end of the reservoir by a reciprocally-distancing movement between reservoir and cap, in order to enable connection between the inside of the reservoir and the inside of the container. For this puipose one or more openings 6 are afforded which enable, when the obturator is extracted from the open end of the reservoir, to place the inside of the reservoir with the inside of the container. A possible and practical realisation of the obturator, represented in the figures, comprises a disc element 5 made at an internal end of the conduit 7 and coaxially with the conduit 7. The disc element is provided with a cylindrical lateral wall 5a which is conformed in such a way as to insert in the

opeii end 8a of the reservoir 8 in order to close it sealingly; this disc element also exhibits a conical protuberance 5b, surmounted by a straight element 5c arranged coaxially of the disc element, which is connected to the cylindrical lateral wall 5 a by a base thereof, and which has a conicity facing towards the outside of the cap 3 or, when the obturator is inserted in the reservoir, facing towards the inside of the reservoir. Naturally the disc element 5, which must insert internally of the reservoir 8 which reservoir in turn inserts in the conduit 7, has a smaller diameter than the diameter of the reservoir 8 and also than that of the conduit 7. The disc element 5 is connected to the lateral wall of the conduit 7 by means of bridge elements 9 which are arranged circumferentially and equidistantly. One of the openings 6 is delimited between one bridge element 9 and another. In this way a plurality of openings is obtained, which openings are arranged circumferentially in the lower part of the conduit 7. To have greater openings, and thus to facilitate the passage of the substances contained in the reservoir towards the container 1 (obviously if the obturator has been extracted from the reservoir) the wall of the conduit 7 stops at a higher level than the lower part of the disc element 5 and the bridge elements 9 connect the lower part of the disc element 5 with the terminal part of the conduit 7. In this way, when the obturator is inserted in the reservoir and hermetically closes the end 8a thereof, the terminal part of the reservoir rests on the bridge elements 9 and the wall thereof is arranged at the openings 6; when the reservoir is removed from the obturator, in a way which will be described herein below, the openings 6 are freed and enable passage of the substance contained in the reservoir.

To improve the seal between the obturator and the reservoir, a plurality of seal rings 10 are located between the internal wall of the reservoir 8 and the

cylindrical lateral wall 5 a of the disc element 5, which seal rings 10 are arranged on reciprocally-parallel planes; the rings 10 constitute a sort of labyrinth seal realised by means of successive circumferential seals, extremely effective against moisture, and are preferably realised on the cylindrical lateral wall 5 a of the disc element.

As previously mentioned, the cap 4 is removably fixed to the mouth 2 of the container 1 by means of a threaded coupling. The reservoir 8 is mobile with respect to the cap 4 from a closed position A (illustrated in figures 1 and 3) to an open position B (illustrated in figure 2) in which the obturator 5 is extracted from the open end 8a of the reservoir 8 and the openings 6 place the inside of the reservoir in communication with the inside of the container. The movement of the reservoir is obtained simply by gripping the part thereof which projects from the conduit 7 and raising the reservoir with respect to the cap 4 in order to make the reservoir slide upwards with respect to the conduit 7, and therefore with respect to the obturator 5; in the end of the reservoir which is closed by the upper wall, there is preferably an annular projection 8b which facilitates gripping the reservoir and raising it.

To define and limit the displacements of the reservoir 8 with respect to the cap 4, the following are preferably present: a first external annular striker 11 fashioned on the external wall of the reservoir 8 which strikes against the upper surface of the cap 4 when the reservoir 8 is in closed position; a second external annular striker 12 which is fashioned on the external wall of the reservoir 8 and which strikes against an internal annular striker 13 fashioned on the internal wall of the conduit 7, and which defines the maximum opening position of the reservoir 8.

As previously mentioned, the capsule can also be provided with various security systems and covering hoods of known type and not illustrated in the

figures: for example, as the reservoir cannot be pushed to insert beyond the closure position, a simple covering made of heat-shrinkable material can be used, which will function as both a security system and a protection system against external agents. Other known systems can also be used. As there are no walls to be lacerated, which therefore would have to be made of soft materials with thin wall sections, and therefore be easily permeable to moisture, the capsule can be made of resistant materials having a considerable thickness which therefore constitute a secure barrier to moisture. The only possible zone of contact with the outside environment (or with the inside of the container when the capsule is inserted) is in the seal zone between the internal wall of the reservoir and the cylindrical zone of the disc element 5, i.e. of the obturator. This zone can be of a considerable length and can be provided with a plurality of parallel seal rings in order to constitute a secure and effective barrier to penetration of moisture into the inside of the reservoir 8, and is thus a barrier to contact with moisture for the substances contained therein.

The capsule is extremely easy to use. The substance is inserted internally of the reservoir and the reservoir is inserted into the conduit 7 up until when the reservoir is closed by the obturator, a position defined by the presence of the striker 11. This operation of inserting the reservoir into the conduit 7 is easy as the striker 13 exhibits a non-sharp projection towards the outside and can easily be passed over by the striker 12. In particular this operation is performed by resting the reservoir on the annular projection 8b, with the open end 8 a facing upwards, and inserting the conduit 7 of the cap 4 from above. The capsule is then inserted, immediately or thereafter, on the container containing the solvent, which is usually a liquid.

At moment of use, first any protective devices are removed and then the reservoir is raised in order to detach it from the obturator, freeing the openings 6 through which the substance contained in the reservoir can fall into the container, which is aided by the conical shape of the upper part of the disc element 5 which constitutes the obturator and by the presence of the straight element on the top thereof.

It is also possible to provide the final user with the container containing the solvent and closed by a normal closure cap, with the cap protected internally of a sealed package and closed in the lower part of the cap 4 by means of an aluminium sheet or the like glued onto the edge of the capsule. In this case the final user, having freed the container from the closure cap, will perform the above-described operations to cause the substance to enter the container. The new and different way of operating of the capsule of the invention, in which the reservoir is raised and not pressed and does not need to cut or lacerate anything but simple has to extract an obturator from its opening, leads to the considerable advantage of avoiding use of soft surfaces having a limited thickness in order to be lacerated. Having eliminated these surfaces, which are the part most easily penetrated by the moisture entering the reservoir, it follows that all the problems connected with the action of the moisture on the substances contained in the reservoir are also eliminated.

The described capsule can also be used in all applications for which known capsules are used, and with respect to known capsules, the described capsule has the advantage of obtaining an effective protection against moisture by means of a less expensive solution.