EP3412590B1 - Container for packaging a liquid drop dispenser, reversibly deformed by air inlet - Google Patents

Description

The invention relates to the field of packaging and distribution of liquids, such as pharmaceutical solutions and in particular eye drops. Its object is a container equipped with a dispensing head, which is organized to contain a liquid while protecting it from the external environment and to deliver this liquid in a controlled manner, drop by drop in particular.

Receptacles are known for containing a liquid, which are organized to preserve this liquid from the external environment and to deliver it in a controlled manner, in particular drop by drop. The applications of such containers are numerous, and a preferred application, but not restrictive as regards the scope of the present invention, lies in the storage and distribution of a pharmaceutical solution, eye drops in particular.

With regard to the preservation of the liquid, it must be protected from the external environment by avoiding its contact with the ambient air which is likely to contain polluting agents, bacteria in particular. For the distribution of the liquid, it is common to give the container a deformable character making it possible to reduce its capacity, at least temporarily, to evacuate the liquid which it contains. Such containers are more precisely flexible wall, to cause an evacuation of the liquid from a compression exerted by the user on this wall, and they are equipped with a dispensing head, to achieve the two objectives that are the preservation and controlled distribution of liquid.

However, the solutions provided to specifically achieve one and the other of these objectives are likely to be antagonistic, and the efforts of designers in the field relate in particular to the search for a compromise between the various solutions. It must also be taken into account a simple desired structure of the container, the cost of obtaining must not be prohibitive given with regard to its consumable nature, and the use of which must be convenient for the user.

It will be noted at this stage of the description that it is common in the field to use a filter membrane to prevent the passage of polluting agents from the outside of the container to the liquid it contains. This membrane, placed in the vicinity of a nozzle which the dispensing head comprises for discharging the liquid from the container, allows liquid to pass through it under the effect of the compression exerted in the container by deformation of the wall. .

According to a first approach, it has been proposed to give the container an irreversible, or almost irreversible, deformable character. An internal wall of the container delimiting the capacity for receiving the liquid is organized as a bellows, and is enveloped by an external sheath. This container also contains a filter membrane which has an air-impermeable nature, to prevent an admission of outside air to the liquid contained in the container, under the effect of a withdrawal of the liquid delivered. For example, we can refer to patent documents FR 2 661 401 and FR 2,770,495 (Where US 6,336,571 ), which describe such receptacles.

The problem to be solved of the controlled delivery of the liquid arises. According to the document FR 2,770,495 ( US 6,336,571 ), a microporous pad acting as a flow regulator is placed in the dispensing head of a container with a strictly irreversible deformation wall. An intermediate reserve is made downstream of the pad and upstream of an air-impermeable filter membrane. Such a container has a complex structure, and the manufacturing cost, both of the reservoir intended to contain the liquid to be dispensed and of the dispensing head, is high. In addition, it is not possible by means of such a container with an irreversible deformation wall to distribute all of the liquid contained in the reservoir. Indeed, the bellows shape does not allow the last drops to be expelled, so that part of the liquid is wasted. The document FR2770495 discloses a container according to the preamble of claim 1.

According to a second approach, it has been proposed to give the container a capacity for reversible deformation. Reference may in particular be made to the document FR 2 816 600 (Where US 2004/0074925 ), which describes such a container. The structure of the dispensing head of this container is simple. It contains a filter membrane which aims to preserve the liquid from pollutants likely to be present in the ambient air. It is also planned to strictly preserve the liquid from the ambient medium before first use. To this end, the dispensing head is movably mounted on the neck of the receptacle, with a view to perforating a cap extemporaneously during a first dispensing operation. However, it emerges from this arrangement, and more particularly from the mobility of the dispensing head relative to the container, a risk of a loss of sealing between them after perforation of the cap and assembly by the user of the dispensing head. distribution inside a neck of the container, in particular by tight fitting. If this risk can be reduced, such an approach tends to increase the complexity of the distribution head, to the detriment of the primary interest sought in its simplicity of structure. In addition, the residual presence of the seal is liable to form an inopportune obstacle to the controlled delivery of the liquid.

It emerges that the designers in the field are still faced with a compromise to be found between simplicity of the dispensing head, preservation of the liquid vis-à-vis polluting agents possibly present in the ambient air, ability to dose the liquid delivered, and optimal use of all the liquid in the tank.

The present invention is part of this search for a compromise, and aims to provide a container for packaging a liquid to be distributed dropwise which offers a solution responding to such a compromise. The invention relates more specifically to the packaging of a sensitive liquid, such as a pharmaceutical, biological or similar solution, eye drops in particular.

The inventive approach of the present invention has generally consisted in choosing first of all a container of the type comprising a reservoir with a wall with elastically reversible deformation by admission of air inside the container. This choice aims to allow delivery of the liquid under the effect of a pressure exerted against this wall, and to allow a spontaneous return of the container to its initial configuration after delivery of a dose of liquid. Such a reservoir with a reversible deformation wall already presents in itself the advantage of a great simplicity of manufacture, compared to irreversible deformation tanks of the prior art, which require a large number of parts and assembly operations.

In general, such a container according to the present invention will be recognized in that it is equipped with a dispensing head comprising a hollow body which is provided with a nozzle for delivering the liquid and which contains a microporous pad of hydrophobic material. placed downstream of the reservoir across the body of the dispensing head. Said body is assembled irreversibly inside the neck of the container.

Furthermore, it is proposed to equip the receptacle with a removable cap for sealing the nozzle which, associated with said microporous pad of hydrophobic material, obstructs the spontaneous flow of the liquid out of the capacity of the receptacle reserved for its storage to the nozzle. These arrangements are such that the spontaneous passage of the liquid through the hydrophobic microporous pad is prohibited when the cap tightly closes the nozzle, and this throughout the duration of use of the container. Conversely, the free flow of the liquid out of the capacity of the container reserved for its storage, through the hydrophobic microporous pad, is authorized when the nozzle is released, with a view to the desired delivery of a dose of liquid by pressure exerted against the nozzle. container wall. In addition, the passage of air is allowed by suction through the hydrophobic microporous pad towards the storage capacity after delivery of a dose of liquid, this suction being caused by the elastic return of the wall of the container to its initial conformation. , return by which the container returns to its initial shape notwithstanding a withdrawal of a dose of liquid.

It will be noted that the microporous pad is preferably made of polyethylene, or similar material, which gives it a hydrophobic character so that it is not wettable, its microporous character nevertheless allowing the passage of the liquid through it, provided that the differential pressure, induced by the pressure exerted by the user, is sufficient.

Such a configuration of the container, and more particularly the combination between the reversible deformation reservoir, the microporous pad and the tight sealing cap, is quite advantageous. Indeed, when the cap is returned to the sealed position of the nozzle, after the suction of air following the delivery of a dose of liquid and the elastic return of the wall of the container to its initial configuration, it a pressure difference is created between the parts upstream and downstream of the buffer through which a pressure drop is created. This pressure difference prevents the liquid in the container from passing through the pad, even if you accidentally press on the container wall, and it seals the bottle, while protecting the liquid it contains from external contamination. . In addition, such a configuration avoids any stagnation of liquid downstream of the pad, since the non-expelled liquid is sucked back into the capacity of the container.

The container advantageously meets an objective of the invention, which is to ensure optimum use of all the contents of the reservoir, and this in two different ways. On the one hand, thanks to its elastically reversible deformation wall, the container retains an intact liquid expulsion capacity until the last drop of liquid. In fact, because air is drawn into the container to replace each dose of liquid expelled, the expulsion pressure available in the bottle is always the same throughout use, until the distribution of the last drop. On the other hand, as explained above, there remains downstream of the tampon no drop of liquid liable to be contaminated by external agents, and which should be eliminated before any new distribution of a clean dose.

In addition, the microporous pad, through which a pressure drop is created, acts as a flow regulator, which promotes the controlled distribution of doses of liquid. In addition, it prevents the liquid contained in the bottle from flowing when the cap is removed, even when the bottle is in the inverted position, the dispensing head being directed downwards, as long as no pressure is exerted on the wall of the container.

In the context of an application of the container to a sensitive liquid, in particular a pharmaceutical solution, the dispensing head is preferably equipped with a filter membrane intended to protect the liquid from an admission of polluting agents present in the ambient air, bacteria in particular. According to the invention, a membrane is then chosen which is at least partly hydrophilic and at least partly hydrophobic, to allow the passage of liquid and air alternately through it, and which is placed in the distribution head in upstream of the nozzle, between it and the buffer. The partially hydrophilic nature of the membrane allows the liquid to pass through it under the effect of the compression exerted in the container by deformation of the wall, while its partially hydrophobic nature allows outside air to enter the container. , when the latter resumes its initial shape elastically after each compression exerted by the user.

The membrane also advantageously constitutes an additional pressure drop, which ensures, in combination with the hydrophobic microporous pad, that no liquid leakage out of the container occurs until the wall of the container is compressed.

In order to promote the passage of air through the membrane, the invention then provides that it is possible to keep this dry membrane between two liquid deliveries, when the container is in the resting position on its base, thanks to the presence an intermediate chamber arranged interposed between the microporous pad and the membrane. Such an intermediate chamber can also be used to constitute a chamber for regulating the delivery of the liquid. To this end, it can advantageously be given a volume sufficient to collect at least one drop of liquid to be dispensed during an operation for delivering the liquid to make it drop dropwise from the dispensing head.

The volume of the intermediate chamber according to the invention also constitutes a reserve of air which, when the nozzle is closed by the cap, maintains a pressure which tends to prevent the liquid from passing through the microporous pad. It will be noted that in association with the intercalary chamber, the character hydrophobic microporous pad promotes a role of obstacle opposing the passage of liquid through it.

The intermediate chamber according to the invention also constitutes a capacity for receiving the liquid which has not yet passed through the membrane when pressure is ceased to be exerted on the wall of the container. For this, it is advantageous to ensure that the intermediate chamber extends over the entire surface of the membrane and that it is located at an axial distance from it sufficient to promote drying of the membrane as soon as the pressure exerted on the wall of the container ceases after delivery of liquid, and this container is returned to its rest position, resting on its base and the dispensing head at the top. As a result, any remaining liquid which, not having been expelled, remains contained in the intermediate chamber, does not continue to wet the membrane by capillary action. It will be noted that the hydrophobic nature of the microporous pad also promotes drying of the membrane.

By virtue of its various characteristics, as they were mentioned above and which will be more fully defined and described below, the invention has the advantage, in industrial practice, of being free from complex control systems. dynamic closure that was used previously. Thanks to the arrangements provided for by the invention, there is no need for a cap or other tear-off partition, or a valve of another shape, or a procedure for opening the bottle by translation or rotation of the bottle. distribution head with respect to the reservoir container for liquid to be distributed dropwise.

In particular, the advantageous combination of the presence of the hydrophobic microporous pad, that of the filtering membrane, and that of the intermediate chamber between them, which jointly confer on the dispensing head both a regulating function of the flow of liquid during the expulsion of the latter and a function of sealing and drying the membrane in combination with the pressure of the air retained in the intermediate chamber due to the tight closure of the cap on the head of distribution.

A microporous pad which is quite suitable in the context of the invention has, for the passage of the liquid in the longitudinal direction, microchannels whose average pore diameter is between 0.3 and 10 microns.

Such a range of values is particularly suitable in the privileged field of application of the invention, which is the storage and distribution of a pharmaceutical solution, in particular of eye drops.

In addition, it ensures that the tampon will produce sufficient pressure drop to isolate the membrane from the liquid in the container before first use. This advantageously prevents the membrane from degrading on contact with the liquid during the storage phase of the container before the first use.

In addition, it is quite advantageous in the context of the invention to combine such a microporous pad with a partially hydrophilic and partially hydrophobic membrane, the pore diameter of which is smaller than that of the pad, in particular between 0.1 and 0.2 microns. Improved sealing and flow regulation properties of the dispensing head are thereby obtained in particular.

The membrane may be made of a polymer material, based for example on a polyamide resin or on a polyether sulfone, which gives it a hydrophilic character. It is then made partially hydrophobic by modifying its structure over part of its surface. Such a modification can be carried out in a manner which is conventional in itself, for example by grafting in the presence of an initiator of radical reactions. The treatment is advantageously carried out so as to make the membrane hydrophobic on a middle band occupying 20 to 50% of its surface which is wetted during the expulsion of the liquid.

Preferably, the body is assembled inside the neck by interlocking in close contact.

The body is preferably elastically deformable for its introduction by force inside the neck of the container, a centering member preferably being provided at the base of the body to facilitate such an introduction in strength. This centering member preferably consists of radial junction wings by interlocking the body of the dispensing head on the neck of the container, the wings delimiting hollow sectors between them.

To further promote the sealing of the container and the introduction into close contact of the body inside the neck of the container, the outer surface of the body of the dispensing head is advantageously equipped with a peripheral ring coming from said body with which it constitutes a one-piece assembly, this ring preferably being in plurality and axially repeated on the body.

It will be noted that the body is advantageously obtained by molding, under conditions such as a ring, coming from the joint plane, is radial to its general axis of extension, and in particular where appropriate parallel to the aforementioned peripheral ring. This ring resulting from the joint plane is more particularly located at the distal end of the body, at the junction limit of the centering member, in order to best promote the seal between the dispensing head and the container.

The removable cap for its part is preferably attached to the container by screwing to promote the tightening of the cap on the dispensing head, and therefore the seal between these members.

To this end, the cap advantageously comprises a combination of sealing members associating a pin penetrating inside the nozzle of the dispensing head and a skirt covering this nozzle. The pin and the skirt are advantageously derived from the cap, when the latter is obtained in a single piece, in particular by molding.

• La figure 1 et la figure 2 sont des schémas en coupe axiale qui illustrent un récipient pour le conditionnement d'un liquide selon des variantes respectives de réalisation de la présente invention.
• La figure 3 est une vue en coupe du récipient illustré sur la figure 2, prise radialement dans la zone d'un organe de centrage que celui-ci comporte.

The present invention will be better understood on reading the description which will be given in relation to the figures of the attached sheet, in which:

• The figure 1 and the figure 2 are diagrams in axial section which illustrate a container for packaging a liquid according to respective variant embodiments of the present invention.
• The figure 3 is a sectional view of the container illustrated in figure 2 , taken radially in the zone of a centering member which the latter comprises.

On the figures 1 and 2 , a container for conditioning a liquid 1 is spontaneously reversible deformation, to allow distribution of the liquid 1 from a manual compression exerted by a user of its wall 2 and a spontaneous return to its initial shape by admission of 'air. This container provides a capacity 15 for storing the liquid 1, and is equipped with a distribution head 3 for the drip liquid. This dispensing head 3 mainly consists of a hollow body 4 provided with a nozzle 5, and a removable cap 6 for closing off the nozzle 5. An anti-bacterial, partially hydrophilic and partially hydrophobic filter membrane 7, therefore permeable to air but also to liquid, is arranged upstream of the nozzle 5, to protect the liquid against an undesirable introduction of polluting agents possibly present in the ambient air, bacteria in particular.

The body 4 of the dispensing head 3 houses in its internal recess a microporous pad 8 which is made of a hydrophobic material, in particular of polyethylene, to prevent the passage of the liquid 1 towards the nozzle 5, in the absence of compression. on the wall 2 of the container. This microporous pad 8 is placed upstream and at a distance from the membrane 7, so as to provide between itself 8 and the latter 7 an intermediate chamber 9.

The chamber 9 extends over the entire surface of the tampon so as to constitute a reserve of air which exerts, when the nozzle 5 is closed by the cap 6, a pressure over the entire surface of the tampon 8 preventing the liquid 1 from passing. through the microporous pad 8 when the nozzle 5 is closed by the cap 6. More precisely, the cap 6 obstructs an evacuation of the air out of the container, and more particularly out of the intermediate chamber 9. The air being confined downstream of the microporous pad 8, the latter obstructs the passage of the liquid 1 through it as long as the nozzle 5 is closed by the cap 6. Conversely for delivery of the liquid 1, the microporous pad 8 does not prevent this. delivery as soon as the air can be evacuated out of the container through the nozzle 5. The intermediate chamber 9 is used to allow spontaneous regularization the flow of liquid 1 passing through the microporous pad 8, prior to its distribution through the nozzle 5.

The intermediate chamber 9 extends over the entire surface of the membrane so as to constitute a capacity for collecting the liquid 1 away from the membrane 7 when the pressure on the wall 2 of the container is stopped and thus favoring the drying of the membrane between two deliveries of liquid.

The body 4 is permanently assembled inside the neck 10 of the container, by force fitting. According to the various variants illustrated on the figure 1 and the figure 2 , this interlocking is achieved either directly by close contact between the outer surfaces of the body 4 and the inner surfaces of the neck 10, as illustrated on figure 1 , or and preferably by means of toroidal rings 11 formed at the periphery of the body 4, as illustrated in FIG. figure 2 . It will be noted in these exemplary embodiments the preferred presence of a centering member 12 formed at the base of the body 4 to facilitate its introduction inside the neck 10 of the container. The centering member 12 illustrated for example generally consists of radial junction wings 13 by interlocking the body 4 on the neck 10, the wings 13 defining between them recessed sectors, more particularly visible on the figure 3 .

Finally, in the illustrated variants, we will note the assembly by screwing the cap 6 onto the neck 10 of the container, by means of cooperating reliefs 14. To facilitate the screwing of the cap 6 on the container and to reinforce the seal between one and the other, the cap 6 comprises a pin 15 penetrating inside the nozzle 5 of the dispensing head and a skirt 16 covering the nozzle.

Claims (13)

1. Container for the packaging of a liquid to be dispensed drop by drop, comprising

   - a reservoir with an elastically deformable wall (2) that is reversible by the admission of air inside the container in order to deliver the liquid (1) under the effect of pressure exerted against this wall (2) and to allow spontaneous return of the container to its initial conformation after delivery of a dose of liquid (1),

   - a base on which the container can stand in a position of rest between two deliveries of liquid;

   - a dispensing head (3) comprising a hollowed-out body (4) that is provided with a nozzle (5) for delivering liquid (1) and an anti-bacterial filtering membrane (7) that is disposed upstream of the nozzle,

   - the container being configured such that when it rests on its base the dispensing head is uppermost; and

   the container being characterized in that it comprises a hydrophobic microporous pad (8) that is placed downstream of the reservoir inside the body (4), said body (4) being assembled irreversibly inside a neck (10) of the container, said filtering membrane (7) being disposed between the nozzle and the pad (8), the membrane (7) being partially hydrophilic for allowing the liquid to pass through it under the effect of the overpressure created in the container by pressure of its wall, and partially hydrophobic to allow the passage of air through it under the effect of the negative pressure created in the container by releasing the pressure exerted on its wall, and in that it comprises an intermediate chamber (9) for regularising the delivery of the liquid, which is provided interposed between the microporous pad (8) and the membrane (7), said intermediate chamber extending over the entire surface of the membrane and at a sufficient axial distance to accommodate the liquid that has not yet passed through the membrane when pressure ceases to be exerted on the wall of the container and thus to assist the drying of the membrane between two deliveries of liquid, such that any residue of liquid, which, having not been expelled does not succeed in wetting the membrane by capillarity when the container is placed in its position of rest standing on its base.
2. Container for the packaging of a liquid to be dispensed drop by drop according to claim 1, characterised in that the microporous pad (8) is produced from polyethylene in order to confer on it its hydrophobic character, its microporous character nevertheless allowing passage of the liquid through it under the effect of a pressure differential caused by a pressure exerted by a user against the wall of the container.
3. Container for the packaging of a liquid to be dispensed drop by drop according to claim 1 or 2, characterised in that the microporous pad (8) has microchannels, the mean pore diameter of which is between 0.3 and 10 microns.
4. Container for the packaging of a liquid to be dispensed drop by drop according to one of the preceding claims, wherein the filtering membrane (7) has pores of a diameter smaller than the diameter of the pores of the microporous pad and comprised between 0.1 and 0.2 microns.
5. Container for the packaging of a liquid to be dispensed drop by drop according to any of the preceding claims, characterised in that the body (4) is assembled inside the neck (10) of the container by fitting in close contact.
6. Container for the packaging of a liquid to be dispensed drop by drop according to claim 5, characterised in that the body (4) is elastically deformable for forcible introduction thereof inside the neck (10) of the container, a centring member (12) being provided at the base of the body (4) to facilitate such forcible introduction.
7. Container for the packaging of a liquid to be dispensed drop by drop according to claim 6, characterised in that the centring member (12) consists of radial fins (13) for joining the body (4) of the dispensing head to the neck (10) of the container by fitting together, the fins (13) delimiting hollowed-out sectors between them.
8. Container for the packaging of a liquid to be dispensed drop by drop according to any of claims 5 to 7, characterised in that the external surface of the body (4) of the dispensing head is equipped with at least one O-ring (11) issuing from said body (4), with which it constitutes a single-piece assembly, optionally a plurality of axially distributed O-rings.
9. Container for the packaging of a liquid to be dispensed drop by drop according to any of the preceding claims, characterised in that the body (4) of the dispensing head is obtained by moulding under conditions such that a ring (17), resulting from the moulding parting plane, is situated at the distal end of the body (4) at the junction boundary of the centring member (1), which assists the obtaining of a sealed connection between the dispensing head and the container.
10. Container for the packaging of a liquid to be dispensed drop by drop according to any of the preceding claims, further comprising a removable cap (6)for sealed closure of the nozzle (5) .
11. Container for the packaging of a liquid to be dispensed drop by drop according to claim 10, characterised in that the removable cap (6) is attached to the container by screwing.
12. Container for the packaging of a liquid to be dispensed drop by drop according to claim 11, characterised in that the cap (6) comprises a combination of sealing members associating a spike (15) penetrating inside the nozzle (5) of the dispensing head and a skirt (16) fitting on top of this nozzle (5) .
13. Assembly comprising a container for the packaging of a liquid to be dispensed drop by drop according to one of the preceding claims, and a liquid contained in said container, the liquid being a pharmaceutical solution, for example eye drops.

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