EP4090606B1 - Locking cover for a container having a neck, with a cap having breakable securing tabs - Google Patents

Description

FIELD OF THE INVENTION

The present invention relates to a locking cap for a neck container intended to lock a stopper in the neck of the container as well as a method for preparing a locking cap.

It relates more particularly to a locking cap for a neck container used in the medical or pharmaceutical field, provided with a breakable capsule to demonstrate the inviolability of the container.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

Inviolability or proof that a medical product has already been used or that a container containing a medical solution has already been opened, voluntarily or not, is an important issue, particularly with a view to limiting the risks of contamination of the patient. The invention is more particularly interested in the case of necked containers.

We know of the document FR2893922 a locking cap disposed on a cap to lock it assembled to a neck container. This locking cap includes a central orifice for accessing the contents of the container through the cap, this orifice being closed by a capsule welded to the cap. In order to access the contents of the container, it is necessary to break the connection between the capsule and the cap. The capsule being thus irreversibly separated from the cap, it is impossible to reuse the capsule. The breaking of the connection therefore allows us to demonstrate that this is the first use of the container. However, the assembly process for this locking cap is complex and presents in particular a welding step. It would be desirable to have a simpler assembly process. In addition, the fact that the capsule is welded can cause the capsule to hold very tightly to the locking cap and make breaking the connection not very ergonomic.

The document WO2011/039004 , which discloses a locking cap according to the preamble of claim 1, proposes an alternative approach. In this document, the capsule is not welded to the cap but is configured so as to be able to be detached from the cap irreversibly without the possibility of being returned to its initial state. More particularly, the capsule comprises a flat head as well as fixing lugs projecting substantially perpendicular to the head. These legs are clamped between the different elements constituting the cap during assembly. This vice grip makes it possible to exceed the elastic limit of the fixing lugs so that the latter remain in a folded configuration when the capsule is separated from the locking cap. This folded configuration of the legs, associated with a protrusion at the end of the legs, makes it difficult to reassemble the capsule to the locking cap.

However, it was found that, under certain very specific conditions, it was possible to reinsert the capsule on the cap of the container, making the proof of first use and inviolability of the container less reliable.
We also know documents WO2013034594 And FR1334575 locking caps comprising a capsule provided with breakable fixing lugs. Any attempt to access the contents of the container requires removal of the capsule, which leads to breaking the fixing tabs. It is thus not possible to reposition the capsule on the cap to hide the opening or the attempted opening of the container.
The design and manufacture of capsules equipped with such breakable fixing lugs must be perfectly mastered. The effort to be applied to the capsule to remove it from the cap must not be excessive for the user. At the same time, the fixing tabs should not be too fragile in order to avoid breaking them during the initial assembly of the capsule to the rest of the cap. However, the variations appearing within a manufacturing batch of capsules, or between different manufacturing batches of capsules, can affect this perfect control of the breakable nature of the fixing lugs, which can in turn affect the manufacturing yield during of the initial assembly of the capsules, or affect the ease of use of the solution by making the effort of removing the capsule from one container to another very variable.
Regardless of the solution chosen to close and make access to the contents of a container inviolable, and very generally, the use of any device in the medical field requires its prior sterilization. It is common to carry out this sterilization by irradiating the device with a sufficient dose of gamma rays. We therefore choose the materials constituting such a medical device, particularly when they are made of plastic, so that they are not affected by this irradiation, particularly with regard to their mechanical resistance.

OBJECT OF THE INVENTION

An aim of the invention is to propose a locking cap provided with a breakable capsule remedying at least partly the aforementioned drawbacks. An aim of the invention is in particular to propose a capsule for a locking cap of a neck container, the capsule being provided with breakable fixing lugs which are sufficiently rigid to limit the risk of breakage when assembling the capsule to the cap, while being sufficiently fragile once assembled to encourage this breakage during removal of the capsule.

BRIEF DESCRIPTION OF THE INVENTION

• une cage en matière plastique configurée pour entourer le bouchon et le col et les verrouiller axialement en position l'un par rapport à l'autre ;
• un corps en matière plastique qui est fixé autour de la cage, le corps comprenant un orifice central réservant un accès depuis l'extérieur de la coiffe vers l'intérieur du récipient par l'intermédiaire du bouchon ;
• une capsule configurée pour fermer l'orifice central, la capsule comprenant une tête plate pour recouvrir l'orifice et des pattes de fixation prises en étau entre la cage et le corps. La coiffe de verrouillage est remarquable en ce que :
• chaque patte de fixation présente une zone sécable et,
• la capsule est formée d'une matière plastique différente de la matière plastique de la cage et de la matière plastique du corps, la matière plastique de la capsule étant choisie pour présenter une résistance à la rupture amoindrie par une dose d'irradiation aux rayons gamma de stérilisation de la coiffe.

With a view to achieving this goal, the object of the invention proposes a locking cap for a container with a neck intended to block a stopper in the neck of the container, comprising:

• a plastic cage configured to surround the cap and the neck and lock them axially in position relative to each other;
• a plastic body which is fixed around the cage, the body comprising a central orifice providing access from the outside of the cap to the inside of the container via the cap;
• a capsule configured to close the central orifice, the capsule comprising a flat head to cover the orifice and fixing lugs clamped between the cage and the body. The locking cap is notable in that:
• each fixing bracket has a breakable zone and,
• the capsule is formed of a plastic material different from the plastic material of the cage and the plastic material of the body, the plastic material of the capsule being chosen to present a resistance to rupture reduced by a dose of gamma irradiation sterilization of the cap.

• le matériau de la capsule comprend du polypropylène ;
• la zone sécable correspond à un amincissement local de l'épaisseur de la patte de fixation, tel qu'une encoche ou une rainure ;
• la zone sécable présente une épaisseur comprise entre 30 et 70% de celle de la patte de fixation ;
• la zone sécable est localisée dans une région de jonction de la patte de fixation sur la tête de la capsule ;
• le matériau de la capsule présente une perte d'élongation supérieure ou égale à 25% après avoir reçu une dose d'irradiation de rayons gamma de 50kGy.

According to other advantageous and non-limiting characteristics of the invention, taken alone or in any technically feasible combination:

• the capsule material includes polypropylene;
• the breakable zone corresponds to a local thinning of the thickness of the fixing tab, such as a notch or a groove;
• the breakable zone has a thickness of between 30 and 70% of that of the fixing bracket;
• the breakable zone is located in a junction region of the fixing tab on the head of the capsule;
• the capsule material has an elongation loss greater than or equal to 25% after receiving a gamma ray irradiation dose of 50kGy.

• la disposition de la capsule sur le corps de la coiffe, les pattes de fixation de la capsule s'étendant dans l'orifice central du corps ;
• l'insertion de la cage dans le corps pour prendre en étau les pattes de fixation de la capsule entre le corps et la cage, pour former la coiffe de verrouillage assemblée ;
• la stérilisation par une irradiation aux rayons gamma de la coiffe de verrouillage assemblée.

The invention also relates to a method for preparing a locking cap as previously described, comprising:

• the arrangement of the capsule on the body of the cap, the fixing lugs of the capsule extending into the central orifice of the body;
• inserting the cage into the body to grip the fixing lugs of the capsule between the body and the cage, to form the assembled locking cap;
• sterilization by gamma irradiation of the assembled locking cap.

This gamma ray irradiation can have a dose of between 10 kGy and 20 kGy.

BRIEF DESCRIPTION OF THE FIGURES

• La figure 1 représente une vue en coupe d'une coiffe de verrouillage assemblée conforme à l'invention ;
• Les figures 2a et 2b représentent respectivement une vue de dessous et une vue de dessus d'une capsule conforme à l'invention ;
• La figure 3 représente une vue en coupe d'une zone sécable d'une patte de fixation conforme à l'invention ;
• La figure 4 représente une vue en coupe d'une coiffe de verrouillage conforme à l'invention avant d'être entièrement assemblée.

Other characteristics and advantages of the invention will emerge from the detailed description of the invention which follows with reference to the appended figures in which:

• There figure 1 represents a sectional view of an assembled locking cap according to the invention;
• THE figures 2a And 2b respectively represent a bottom view and a top view of a capsule according to the invention;
• There Figure 3 represents a sectional view of a breakable zone of a fixing bracket according to the invention;
• There figure 4 represents a sectional view of a locking cap according to the invention before being fully assembled.

DETAILED DESCRIPTION OF THE INVENTION General overview of the locking cap

There figure 1 represents a locking cap 1 for container 2 with neck 3, in accordance with the invention, intended to block a plug 4 in the neck 3 of the container 2, the cap 1 being shown here simply placed on the neck 3 without being locked.

The neck 3, here of circular opening, has at its end an external peripheral lip 5 on which the locking cap 1 is locked when the cap 1 is locked on the neck 3 of the container 2. The cap 4 has a classic shape , generally cylindrical, T-shaped with a head 4a and a foot 4b, the head being of slightly greater diameter than the foot 4b, so that, when the foot 4b of the plug 4 is introduced into the neck 3, the head 4a comes into abutment against lip 5 of neck 3.

The locking cap 1 comprises a cage 6 capable of surrounding the plug 4 and the neck 3, when the cap 1 is in configuration locked on the neck 3 of the container 2, as well as a body 7 capable of being fixed around the cage 6. The cage 6 allows the blocking of the cap 4 in the neck 3, by means of flexible tabs 8 arranged on the periphery of the cage 6, intended to be blocked under the lip 5. We could of course consider other means of blocking the plug 4 by the cage 6. In the assembled configuration of the cap 1, the body 7 laterally covers completely the cage 6 so as to prevent any access to the cage 6 and the tongues 8 from outside the body 7. The body and the cage are both formed of a plastic material which is not likely to be degraded during gamma ray sterilization of the cap.
The elongation loss of a material is a criterion commonly used to measure the effect of irradiation on its tensile strength. In the context of this application, it will be considered that a material is not degraded after having received a dose of gamma rays sufficient to sterilize it, when the loss of elongation of this material is less than 25% after having received a gamma ray irradiation dose of 50kGy. On the contrary, we will consider that this material is degraded after having received a dose of gamma rays sufficient to sterilize it, and its resistance to rupture reduced, when the loss of elongation of this material is greater than or equal to 25% after having received a gamma ray irradiation dose of 50kGy.
The body 7 and the cage 6 are not necessarily formed of the same material, and for example the plastic material forming the body 7 can be polybutylene terephthalate (also known under the abbreviation "PBT") and that of the cage 6 of polycarbonate (also known by the abbreviation “PC”). These two plastic materials require a dose of gamma rays well above 500kGy, or even above 1000kGy, for the elongation loss generated by this irradiation to exceed the 25%. They are therefore not likely to be degraded during gamma ray sterilization of the cap in the dose ranges envisaged.
Continuing the general description of the cap 1 of the figure 1 , the body 7 also includes a central orifice 9 providing access from the outside of the cap 1 to the inside of the container 2 via the cap 4. It is therefore possible through this orifice 9 to access the contents of the container 2, for example by inserting the needle of a syringe through the stopper 4. It will be noted that obviously, as is visible on the figure 4 , the body 7 and the cage 6 also each have a central opening to allow access to the cap 4 and therefore to the contents of the container 2.

The locking cap 1 also comprises a capsule 10 configured to close the central orifice 9 and demonstrate the inviolability of the container 2. This capsule 10 comprises a flat head 11 to cover the orifice 9 as well as a plurality of tabs. fixing 12. The fixing lugs 12 are held in a vice between the cage 6 and the body 7 to retain the capsule 10 assembled to the locking cap 1.

Detailed description of the capsule

THE figures 2a And 2b show a capsule 10 according to the invention for closing the central orifice 9 of the body 7. This capsule 10 has fixing lugs 12, here for example eight lugs 12, which project in the rest position perpendicular to the flat head 11 of capsule 10.

The capsule 10 with the flat head 11 and the fixing lugs 12 is advantageously formed in one piece of molded plastic material. The flat head 11 may have the shape of a disc or another more complex shape such as a polygon for example, as long as the flat head surface 11 completely covers the central orifice 9.

The flat head 11 can also be provided with gripping elements 11a, here in the form of reinforcement points, to facilitate gripping of the capsule 10 when removing it from the cap 1.

The fixing lugs 12 are distributed circularly and distributed along the periphery of the orifice 9 of the body 7 when the capsule 10 is in assembled configuration with the body 7. The fixing lugs 12 may have a beveled free end and/or provided with a blocking bead 12a. The thickness of the fixing lugs 12 is between 0.3 and 0.6 mm, it can for example be 0.37 mm.

The locking bead 12a has larger dimensions than those of the rest of the fixing bracket 12; its purpose is to better retain the capsule 10 assembled to the cap 1 by generating additional resistance, if one attempts to remove the capsule 10 by sliding the fixing lugs 12 out of their vice. In the absence of locking bead 12a, an initial resistance exists requiring the application of a predetermined force to release the fixing lugs 12 from their vice. This resistance comes from the folded shape that the fixing lugs 12 take when they are gripped between the body 7 and the cage 6. The presence of the blocking bead 12a creates the need to apply a greater force than that initially predetermined to release the fixing lugs 12 from their vice. This additional force is all the more important as the dimensions of the bead 12a are increased. Preferably, the bead 12a has a thickness 35% to 170% greater than that of the fixing bracket 12, i.e. for example a thickness of between 0.5 and 1.0 mm for a fixing bracket 12 with a thickness of 0.37 mm.

It is desired that the capsule 10 is breakable and can break, more particularly at the level of the fixing lugs 12, when it is removed from the cap 1. The removal is thus irreversible and is a reliable indicator of first use because the capsule 10 does not cannot be reassembled to cap 1.

In order to achieve this objective, we seek to reduce the resistance to rupture of the capsule 10 so that the force necessary to release the fixing lugs 12 from their vice becomes greater than the force necessary to break the lugs of the capsule 10. Thus the capsule 10 will break before the flexible legs 12 can be released from their vice.
To achieve this, the capsule 10 is formed of a plastic material whose resistance to rupture is reduced by irradiation with gamma rays in a dose aimed at sterilizing the cap 1. In other words, the material from which the capsule 1 is made becomes more fragile, and its resistance to rupture reduced, after having undergone gamma irradiation. This material is characterized by an elongation loss greater than or equal to 25%, if it receives a gamma ray irradiation dose of 50kGy. It may be primarily a polypropylene-based material, or it may consist of polypropylene.
Gamma ray irradiation aimed at making the cap sterile is preferably carried out with a dose typically between 10 kGy and 20 kGy, for example 15 kGy, and after the capsule 10 has been assembled to the rest of the cap 1. Thus only the plastic material constituting the capsule 10 will be degraded by this sterilization step, the plastic materials forming the cage 6 and the body 7 having been chosen so as not to be susceptible to excessive deterioration during exposure to gamma rays.
It should be noted that possible degradation of the material of the capsule does not present a risk of contamination of the contents of the container because the capsule, due to its position and its configuration in the cap, is not in contact with or exposed to the contents of the container. and therefore does not risk contaminating it by generating, for example, particles during its degradation.

The force necessary to apply to break the legs 12 of the capsule 10 is therefore lower after the sterilization gamma irradiation and it becomes lower than the force necessary to release the flexible legs 12 from their vice.

In addition, and to promote and locate their ruptures, the fixing lugs 12 each have a breakable zone 12b visible on the Figure 3 . This breakable zone 12b advantageously corresponds to a local thinning of the thickness of the fixing tab 12. It can thus be for example a notch or a groove having a fixed or progressive thinning delimited by one or more slopes inclined.

Preferably, the breakable zone 12b corresponds to a portion of the fixing tab 12 having a thickness of between 30% to 70% of that of the fixing tab 12, for example a thickness of between 0.11 and 0.26 mm for a tab of fixing thickness 0.37mm. The dimensions of the breakable zone, and more generally of the fixing lugs 12, are therefore advantageously chosen to avoid any risk of breakage during the assembly of the elements of the cap 1, before the irradiation step.

Also advantageously, the breakable zone 12b is located in a junction region of the fixing tab 12 on the head of the capsule 10.

The properties of the breakable zone 12b and of the material of the capsule 10 have the effect of reducing the breaking resistance of the capsule 10 after assembly of the locking cap 1, but of preventing the tabs from breaking during of the assembly, and to better locate the place where the breakage will take place. The presence of these breakable zones 12b combined with gamma irradiation makes it possible to further reduce the force necessary to break the breakable zone 12b and ensure that the capsule 10 breaks at said zones 12b before the fixing lugs 12 can have the opportunity to free themselves from their vice-like grip.

Preparation and use of the locking cap

The operations for preparing the locking cap are now described with reference to the figures 1 And 4 . There figure 4 represents a sectional view of a cap 1 whose constituent elements are being assembled while in the figure 1 the constituent elements of the cap 1 are already assembled and arranged on the neck 3 of the container 2.

We first place a capsule 10 with straight fixing lugs 12 on the body 7 of the cap 1, so that the fixing lugs 12 extend into the central orifice 9 of the body 7 and the flat head 11 completely covers the orifice 9. Advantageously, the capsule 10 is arranged upside down, the fixing lugs 12 upwards and the body 7 is then placed on the capsule 10 so that the lugs 12 penetrate through the central hole 9.
We then insert the cage 6 into the body 7 ( figure 4 ) until the cage 6 abuts against the body 7 to grip the fixing lugs 12 of the capsule 10. The latter fold, between the body 7 and the cage 6, and are held in this position due to the blocking by lugs of the cage 6 in the body 7. The assembled locking cap 1 is thus formed ( figure 1 ). At this stage, the cap having not yet been sterilized by gamma irradiation, the material forming the capsule has not been degraded and therefore retains its initial rupture resistance. The risk of the legs breaking at this stage is therefore low, even in the presence of the breakable zones 12b.

A plug 4 is introduced into the cage 6 until it abuts against it. When the plug 4 is inserted into the cage 6, flexible tabs 8' deform then return to their initial shape when the plug 4 is in place by providing positive support behind the head 4a of the plug 4 so as to keep it assembled in the cap 1 as is visible on the figure 1 .

The assembled locking cap 1 is then sterilized by irradiation with gamma rays in a dose of between 10 kGy and 20 kGy, preferably of the order of 15 kGy. During this step, only the mechanical properties of the material of the capsule 10 are effectively modified, making it less resistant to breakage, the other elements of the cap being formed of different materials not likely to be degraded during this step.

At the end of this step, the locking cap 1 is ready to be used to lock the cap 4 in the neck 3 of a container 2 with a neck 3. The assembly formed by the locking cap 1 and the cap 4 can then be mounted on a container 2 by introducing, by simple axial pressure on the capsule 10, the foot 4b of the cap 4 into the neck 3 of the container 2. We obtain a watertight closure of the container 2 by the cap 4 and tamper-proof thanks to the locking cap 1 of which the flexible tabs 8 lock under the lip 5 of the collar 3.

The presence of the capsule 10 testifies to the inviolability of the container 2. Indeed, to access the contents of the container 2 it is necessary to remove the capsule 10. When removing the capsule 10, the force necessary to cause the rupture of the breakable zone 12b being less than the force necessary to release the fixing lugs 12 from their vice, the breakable zones 12b of the majority, i.e. more than 50% and preferably more than 80% (or even all) of the lugs of fixing 12, break and a piece of the tabs remains caught in the cap 1. It is then no longer possible to close the orifice 9, the breakage of the breakable zones 12b thus testifies to a first use of the container 2.

Furthermore, the inviolable nature of the cap 1 also comes from the fact that the cap 1 is configured to break and not be reusable, for example by breaking the elements responsible for assembling the cage 6 with the body 7, if we try to remove it once assembled in container 2.

Of course, the invention is not limited to the mode of implementation described and alternative embodiments can be made without departing from the scope of the invention as defined by the claims.

In particular, we could consider other body and cage shapes than those illustrated in the figures. It would also be possible for the locking cap to include additional elements without departing from the scope of the invention as defined by the claims.

Claims (8)

1. Locking cap (1) for a container (2) having a neck (3), which locking cap is intended to block a stopper (4) in the neck (3) of the container (4), comprising:

   - a cage (6) made of plastics material and designed to surround the stopper (4) and the neck (3) and to lock them axially in position relative to one another;

   - a body (7) made of plastics material and fastened around the cage (6), the body comprising a central orifice (9) which provides access from the exterior of the cap (1) to the interior of the container (2) via the stopper (4);

   - a capsule (10) designed to close the central orifice (9), the capsule (10) comprising a flat head (11) for covering the orifice (9), and fastening tabs (12) caught between the cage (6) and the body (7);

   the locking cap (1) being characterized in that:

   - each fastening tab (12) has a breakable zone (12b),

   - the capsule (10) is made from a plastics material which is different from the plastics material of the cage (6) and from the plastics material of the body (7), the plastics material of the capsule being selected to have a resistance to rupture that is reduced by a dose of gamma ray irradiation which sterilizes the cap (1).
2. Locking cap (1) according to the preceding claim, wherein the material of the capsule (10) has an elongation loss greater than or equal to 25% after having received a dose of gamma ray irradiation of 50 kGy.
3. Locking cap (1) according to either of the preceding claims, wherein the material of the capsule (10) comprises polypropylene.
4. Locking cap (1) according to any of the preceding claims, wherein the breakable zone (12b) corresponds to a local thinning of the thickness of the fastening tab (12), such as a notch or a groove.
5. Locking cap (1) according to the preceding claim, wherein the breakable zone (12b) has a thickness of between 30 and 70% of that of the fastening tab (12).
6. Locking cap (1) according to any of the preceding claims, wherein the breakable zone (12b) is located in a junction region of the fastening tab (12) on the head (11) of the capsule (10).
7. Method for preparing a locking cap (1), the locking cap being in accordance with any of the preceding claims, the method comprising:

   - arranging the capsule (10) on the body (7) of the cap (1), the fastening tabs (12) of the capsule (10) extending into the central orifice (9) of the body (7);

   - inserting the cage (6) into the body (7) to catch the fastening tabs (12) of the capsule (10) between the body (7) and the cage (6), to form the assembled locking cap (1);

   - sterilizing, by gamma ray irradiation, the assembled locking cap (1).
8. Preparation method according to the preceding claim, wherein the gamma ray irradiation dose is between 10 kGy and 20 kGy.

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