CLOSURE PIECE FOR A CONTAINER FOR PHARMACEUTICAL PREPARATIONS, AND CONTAINER PROVIDED WITH THIS CLOSURE PIECE

Abstract

A closure piece is provided for the releasable closure of an opening at the distal end of a cylindrical container for pharmaceutical preparations. The container may be a syringe with a Luer lock fastening. The closure piece includes a cylindrical closure cap, with a cylindrical cavity for receiving and retaining a sealing element, and a sealing element. The sealing element has a rearward offset in relation to an outer edge of the closure cap.

Claims

1. A closure piece for the releasable closure of an opening at a distal end of a cylindrical container for pharmaceutical preparations, the closure piece comprising: a cylindrical closure cap having a cylindrical cavity configured to receive and retain a sealing element, the closure cap comprising a mounting portion which, in a mounted position, faces the container; and a sealing element with a sealing portion, which is arranged at least partially inside the mounting portion, an outer edge of the sealing element having a rearward offset in relation to an outer edge of the mounting portion.

2. The closure piece of claim 1, wherein the rearward offset of the outer edge of the sealing element in relation to the outer edge of the mounting portion measures at least 0.5 mm.

3. The closure piece of claim 1, wherein the closure cap further comprises an actuating portion arranged opposite the mounting portion, wherein the sealing element is arranged at least partially inside the actuating portion, and wherein the outer edge of the sealing element has a rearward offset in relation to an outer edge of the actuating portion.

4. The closure piece of claim 3, wherein an injection point is arranged at a position on a circumferential surface of the actuating portion of the closure cap at an axial distance from an outer rib.

5. The closure piece of claim 3, wherein the actuating portion comprises at least two elongate outer ribs arranged axially in their main orientation and protruding radially outwards from a circumferential surface of the actuating portion.

6. The closure piece of claim 1, wherein a ratio of a length of the sealing element to a length of the closure cap is at most 95%.

7. The closure piece of claim 1, wherein the sealing element comprises an elastomeric material.

8. The closure piece of claim 1, wherein the closure cap has an outer thread configured to connect to a Luer lock fastening of the container, wherein the outer thread is configured according to the standard ISO 594-2.

9. The closure piece of claim 8, wherein the outer thread is configured as a trapezoidal thread.

10. The closure piece of claim 9, wherein at least one punctiform elevation is provided on a thread flank of a thread turn of the outer thread.

11. The closure piece of claim 10, wherein an axial bulge is provided on a portion of the thread turn lying next to a thread entry.

12. The closure piece of claim 10, wherein the thread turn comprises a bevel.

13. The closure piece of claim 1, wherein the closure cap has a continuous opening, wherein a wall thickness of the closure cap at least one of is at most 1.5 mm at a thickest point or varies by not more than 0.5 mm as seen along a length of the closure cap.

14. The closure piece of claim 13, wherein the continuous opening of the closure cap has at least two elongate inner ribs arranged axially in their main orientation and protruding inwardly on an inner wall, wherein the inner ribs have a width of less than 1 mm.

15. The closure piece of claim 14, wherein the width or a cross section of the at least two inner ribs is constant over at least 50% of a length of the at least two inner ribs.

16. The closure piece of claim 1, wherein an axial distance between an outer stop and an inner stop of the closure cap measures 2.85 mm with a tolerance of +/0.2 mm.

17. The closure piece of claim 1, wherein the closure piece comprises a color-stable plastic.

18. The closure piece of claim 17, wherein a color of the closure piece is green grey and corresponds to the tone RAL 7009 according to the RAL color system.

19. A method for contamination-free, releasable closure of a distal end of a cylindrical container for pharmaceutical preparations, the method comprising: closing the distal end of the container with a closure piece, the closure piece comprising: a cylindrical closure cap having a cylindrical cavity configured to receive and retain a sealing element, the closure cap comprising a mounting portion which, in a mounted position, faces the container; and a sealing element with a sealing portion, which is arranged at least partially inside the mounting portion, an outer edge of the sealing element having a rearward offset in relation to an outer edge of the mounting portion.

20. The method of claim 19, wherein at least one of a tightening torque or an opening torque has a slight variance of +/1.0 N*cm in relation to a respectively required torque.

21. A method for producing a closure piece, the closure piece comprising a cylindrical closure cap having a cylindrical cavity configured to receive and retain a sealing element, the closure cap comprising a mounting portion which, in a mounted position, faces the container, a sealing element with a sealing portion, which is arranged at least partially inside the mounting portion, an outer edge of the sealing element having a rearward offset in relation to an outer edge of the mounting portion, and an actuating element with at least two outer ribs, the method comprising: injection molding the closure piece, wherein an injection point is chosen that lies in a region of an actuating portion at a position on an outer circumferential surface of the actuating portion at an axial distance from an outer rib.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0091] The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

[0092] FIG. 1 illustrates a longitudinal section through a closure piece according to the prior art;

[0093] FIG. 2 illustrates a longitudinal section through an exemplary embodiment of a closure piece provided according to the invention;

[0094] FIG. 3 illustrates a longitudinal section through a container for pharmaceutical preparations, which container has a Luer lock fastening, with a partially mounted closure piece;

[0095] FIG. 4 illustrates a profile of the torque when opening a closure piece provided according to the invention, in order to release it from the container;

[0096] FIG. 5 illustrates a profile of the torque when opening a closure piece known from the prior art, in order to release it from the container;

[0097] FIG. 6 illustrates a plan view of a detail of an exemplary embodiment of a closure piece provided according to the invention with a bulge;

[0098] FIG. 7 illustrates a longitudinal section through an exemplary embodiment of a closure piece provided according to the invention with a sealing element;

[0099] FIG. 8 illustrates a longitudinal section through an exemplary embodiment of a closure piece provided according to the invention without a sealing element; and

[0100] FIG. 9 illustrates an oblique view of an exemplary embodiment of a closure piece provided according to the invention.

[0101] Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate embodiments of the invention and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

[0102] In the detailed description that follows, identical reference numbers have been used, for the sake of clarity, to denote essentially identical parts in or on the embodiments. For better illustration of the invention, however, the exemplary embodiments shown in the figures are not always drawn to scale.

[0103] FIG. 1 shows a longitudinal section through a closure piece 100 according to the prior art. This closure piece 100 comprises a cylindrical closure cap 110 with a cylindrical cavity for receiving a sealing element 120, wherein the closure cap 110 comprises a mounting portion 140, which in the mounted position faces the container, and an actuating portion 150.

[0104] The sealing element 120, which has a sealing portion 121, is inserted into the cylindrical cavity of the closure cap 110. It will clearly be seen that the outer edge 122 of the sealing element protrudes past the outer edge 112 of the closure cap 110. This is unfavorable for automated assembly, since it can cause tilting and wedging at the start of the assembly procedure, when the sealing element first comes into contact with the container, in particular with the tip of the container. Thus, centering of the closure piece is also barely possible during the screwing-in procedure, since the sealing element 120 is produced from a resilient elastomeric material. Specifically in fully automated assembly processes and at the high piece numbers required, valuable time may be lost here if the assembly has to be carried out particularly slowly against this background or, for example after wedging, has to be repeated.

[0105] FIG. 2 shows a longitudinal section through a closure piece 1 provided according to the invention for the releasable closure of an opening at the distal end of a cylindrical container for pharmaceutical preparations (not shown), in particular a syringe, such as by a Luer lock fastening. The closure piece 1 provided according to the invention comprises a cylindrical closure cap 10 with a continuous cylindrical cavity 14 for receiving a sealing element 20, the closure cap 10 comprises a mounting portion 40, which in the mounted position faces the container, and an actuating portion 50.

[0106] The mounting portion 40 comprises an outer thread 41 which, in the mounted position, engages in the outer thread of the Luer lock fastening of the container and creates a releasable connection to the latter. The actuating portion 50 is equipped with outer ribs for handling by a user. The cylindrical cavity 14 of the closure cap 10 is of a continuous configuration for receiving the sealing element 20, which is in one piece in this example.

[0107] The figures make clear the pronounced rearward offset of the outer edge 22 of the sealing element 20 in relation to the outer edge 12 of the mounting portion 40 of the closure cap 10.

[0108] The rearward offset according to the invention makes it possible, in a surprisingly simple way, to greatly improve the assembly process and to enhance the process safety, since tilting or wedging can effectively be prevented when fitting the closure piece 1 onto the container or at the start of the assembly process. This is due to the fact that, during assembly, centering of the closure piece 1 first of all takes place via the mounting portion 40, before the sealing element 20 comes into contact with the container, in particular with the tip of the container. Specifically in fully automated assembly processes and at the high piece numbers required, an improvement in assembly safety is of great importance for the efficiency of production and can help to save valuable assembly time.

[0109] The rearward offset of the sealing element 20 in relation to the outer edge 12 of the mounting portion 40 of the closure cap 10 thus enhances the process safety, since centering of the closure piece 1 takes place during the screwing-in procedure even before the sealing element 20 comes into contact with the container. In the present case, the first contact of the sealing element 20 with the tip of the container thus takes place only after centering of closure piece 10 and container, such that the closure piece 10 can be pushed on in a purely axial movement, which is less susceptible to error.

[0110] At the same time, the rearward offset also leads to reduced contamination of other closure pieces, or also of the container, by manufacturing residues that may be present on or at the sealing element 20. These may be, for example, liquids used in the production of the sealing elements, for instance silicone oil. This is in fact often the case with sealing elements which, as here, are produced from an elastomeric material.

[0111] The rearward offset measures approximately 2.5 mm in the example. The danger of contamination can already be reduced with a rearward offset of at least 0.5 mm, such as of at least 1.0 mm or of at least 1.5 mm. In conjunction with the given tolerances, an exemplary rearward offset is moreover in a range of 1.5 to 2.0 mm, of 2.0 to 2.5 mm or of 2.5 to 3.0 mm.

[0112] It will also be seen from FIG. 2 that a rearward offset of the outer edge 23 of the sealing element 20 in relation to the outer edge 13 of the closure cap 10 is also provided. This rearward offset likewise may measure at least 0.5 mm, such as at least 1 mm or at least 1.5 mm. In the example, the rearward offset measures approximately 2.5 mm and is therefore approximately the same size as the rearward offset at the opposite side.

[0113] Accordingly, the rearward offset of the outer edges 22, 23 of the sealing element 20 in relation to the outer edges 12, 13 of the closure cap 10 reliably prevents mutual contamination of closure pieces lying next to one another, for example in transport packages. Structurally, this is achieved by a reduced length of the sealing element 20 relative to the length of the closure cap 10. In the example, the ratio of the length of the sealing element to the length of the closure cap is approximately 70%. A ratio of the length of the sealing element 20 to the length of the closure cap 10 of at most 95%, such as of at most 90% or of at most 85%.

[0114] The assembly and disassembly behavior of the closure piece 1 on the container is determined largely by the design of the outer thread of the closure cap 10.

[0115] FIG. 3 shows a longitudinal section through a container 30 for pharmaceutical preparations that has a Luer lock fastening, with a partially mounted closure piece 1. At its distal end, the container 30 comprises a sleeve 31 which is configured with an inner thread 32 and constitutes the Luer lock fastening. The sleeve 31 encloses a conically tapering tip 33 at the distal end of the container, said tip having an opening 34, for example for discharging a preparation from the chamber 35.

[0116] The outer thread 41 of the mounting portion 40 is configured as an exact mirror-inverted match to the inner thread 32. The outer thread 41 is configured according to the current standard ISO 594-2, although another shape of the rib 42 is provided according to the invention. The rib 42 provided according to the invention is narrower and/or configured with a steeper flank, which leads to a narrower thread turn and therefore to a greater spacing of the adjacent thread flanks. This initially makes it easier to screw the closure piece 1 onto the container 30, since the acting frictional forces are lower.

[0117] This also makes it possible to provide elevations, such as punctiform elevations (not shown), at defined positions on the thread flank, which may be arranged in each case at two opposite positions of the thread flank. Two elevations arranged opposite each other can thus form an elevation pairing. Such an elevation pairing is configured in such a way that, in the assembled position, the elevation points than bear on the thread flank of the Luer lock fastening and are slightly compressed or deformed. This introduces an additional force component into the connection.

[0118] This force component also acts equally in the opening of the closure piece and thus makes it possible to precisely provide a predefined threshold value for opening the closure piece. In this way, a better characteristic, easier for the user, can be made available for the opening torque. In the example, the outer thread 41 comprises a total of four elevation pairings (not shown).

[0119] This also makes it easier to precisely set the torque needed for assembly and/or release and to ensure a predetermined force profile during the rotation movement.

[0120] FIGS. 4 and 5 show, on the basis of illustrative embodiments, the profile of the torque when opening the closure piece 1 in order to release it from the container 30. FIG. 5 shows a characteristic curve for the opening torque of a closure piece 100 according to the prior art, while FIG. 4 shows the characteristic curve for the opening torque for a closure piece 1 provided according to the invention.

[0121] It will be seen that, when opening the closure piece 1 provided according to the invention, a higher force component has to be applied initially in order to release it. When a threshold value is exceeded, the force component to be introduced falls continuously. This makes it easier for the user to open the container 30 and release the closure piece 1. The torque to be applied is accordingly dependent on the opening angle. After overcoming an initial release resistance, which arises on account of the elevations, the acting force component decreases on account of the narrower thread turns which offer more free space, such that the elevations are less compressed. In this way, it is also possible to set a precise torque for opening, for example of 16 N*cm, with a precision of +/0.5 N*cm.

[0122] The release behavior of the closure piece 1 provided according to the invention thus differs from closure pieces 100 known from the prior art in which the force component to be applied at the start of the release procedure hardly falls at all during the release of the closure piece and remains at a high level to the end. This can be seen clearly from the force profile in FIG. 5. This is due to the fact that the closure piece 100 provides a bulging of the thread turn for an additional force component, but the latter then acts throughout the release procedure. This characteristic curve of the torque that is to be applied for release is somewhat unfavorable for the user, since a higher moment has to be applied for almost the entire opening procedure.

[0123] According to the invention, the assembly of the closure piece is further simplified by the fact that the thread turn 41 is made narrower, which increases and thus facilitates the possible angle orientation of closure piece and container to each other at the start of the assembly. To further extend this tolerance range of the required angle orientation, in an exemplary embodiment the portion of the thread turn adjacent to the thread entry is provided with a bulge in order to increase the free space from the outer edge as far as the first thread turn, as a result of which the tolerance range of the angle orientation can be further increased.

[0124] FIG. 6 shows a plan view of a detail of a closure piece 1 with a bulge 44. This slight axial offset of the thread turn, which constitutes the bulge 44, forms an additional free space 45 in a portion arranged adjacent to the thread entry. In this way, the tolerance range of the angle orientation is increased. In other words, the region which defines the required orientation of closure piece 1 and container 30 prior to joining is extended. The configuration, according to the invention, of the thread entry in the illustrative embodiment shown allows this angle tolerance to be extended to a range of +/10. According to the invention, it is possible to fix the angle tolerance in a range of between +/5 and +/15, such as between +/8 and +/12. This leads to a much more favorable assembly process.

[0125] In some embodiments, the thread entry 46 is additionally configured with a bevel 47 in order to further facilitate the joining together.

[0126] The reliability of the container 30 provided with the closure piece 1 provided according to the invention is further influenced by the precision fit of those components which effect the leaktightness of the opening 34 of the container 30. Of crucial importance here, as can be seen from FIG. 3, is the axial spacing between a radially outwardly protruding stop 11 of the closure cap 10, which stop 11 bears on the container 30 in the assembled position, in particular on the collar 36 of the Luer lock fastening 32, and the inner edge 24 of a sealing portion 21 of the sealing element 20, which effects the sealing of the opening 34 of the tip 33. In the assembled position, the sealing portion 21 bears tightly on the tip 33 and encloses the opening 34, wherein the inner edge 24 bears on the opening 34 with a predefined minimum pressing force.

[0127] For the axial positioning of the sealing element 20 in the opening 14 of the closure cap 10, the latter is configured with a radially inwardly protruding peripheral shoulder 15. On its circumferential surface, the sealing element 20 has a likewise peripheral recess 25 which is positioned in such a way that, in the assembled position, the shoulder 15 engages in the recess 25 and forms an axial stop. In this way, it is possible to achieve a precise positioning of the sealing element 20 and therefore of the inner edge 24 that seals the opening 34 of the container 30 (not shown).

[0128] FIG. 7 shows these relationships on the basis of a longitudinal section through a closure piece 1 provided according to the invention with a sealing element 20. In this view, the letter S indicates the so-called settling, i.e. the distance which arises between the inner edge 24 of the sealing element 20 and the container 30 in the assembled position of the closure piece. This is decisive for obtaining the required minimum pressing force in order to seal the opening.

[0129] FIG. 8 illustrates these relationships once again on the basis of a longitudinal section through a closure piece 1 provided according to the invention, which in this view has no sealing element 20. To maintain this settling, a defined distance A is required between the outer edge of the outwardly protruding stop 11 of the closure cap 10, which therefore bears on the collar of the container in the assembled position, and a stop 16, defined by the shoulder 15, inside the opening 14 of the closure cap 10. In the example, an assembly distance of A=2.85 mm is required here with a very low tolerance. The inner stop 16 exerts on the opening the minimum pressing force to be applied by the sealing element 20 in order to permit sealing.

[0130] The closure cap 10 is configured in such a way that a thin and above all uniform material thickness of the side wall is provided over as far as possible the entire length of the closure cap, in order to achieve a high degree of dimensional accuracy. Therefore, the wall thickness of the closure cap 10 at the thickest point is at most 2.0 mm. Viewed along the entire length of the closure cap, the thickness of the wall varies by not more than 0.5 mm, such as by not more than 0.3 mm.

[0131] Moreover, according to the invention, the injection molding method is optimized in the sense that an injection point is chosen that lies in the region of the actuating portion 50. FIG. 9 shows an oblique view of a closure piece 1 provided according to the invention, wherein the injection point for the injection molding method is identified by the letter E in the example shown. The injection point thus lies externally on the circumferential surface of the actuating portion 50 at an axial distance from an outer rib 53. A possible risk of injury to a user can moreover be counteracted in this way, since sharp protruding edges may arise at the gate. In the present case, these potential gate edges lie outside the grip region.

[0132] The rotationally secure retention of the sealing element 20 in the continuous opening 14 of the closure cap is obtained via elongate, radially inwardly protruding inner ribs 51 arranged axially in their main orientation on the inner wall of the opening 14 of the actuating portion 50. To provide uniform pressing, these inner ribs 51 are distributed at uniform intervals about the inner circumference. In the example shown, a total of eight such inner ribs 51 are provided.

[0133] According to the invention, a narrow configuration of the inner ribs 51 is provided which leads to a much smaller displacement volume at an inserted sealing element 20. This greatly reduces the tendency of a sealing element 20 mounted in the closure cap 10 to form an axial offset, and therefore the required spacing after placement of the sealing element, i.e. the settling for maintaining the minimum pressing force, can be precisely maintained. The axial offset of the sealing element in the opening of the closure cap is limited by the inner rib, configured according to the invention, to less than 0.3 mm, such as to less than 0.2 mm or to less than 0.15 mm.

[0134] In the example shown, the inner rib 51 therefore has a width of approximately 0.9 mm. Without restriction to the illustrative embodiment, widths of the inner rib 51 of less than 1 mm, such as of less than 0.9 mm or of less than 0.8 mm, are expedient. Moreover, for a stable fit, the width and the cross-sectional shape of the inner rib 51 are constant over a large part of the length of the inner rib 51, as can be seen clearly from FIG. 8, for example. In other words, except for a small insertion bevel 52 for setting the sealing element, the cross section of the rib is constant along its length. It has proven expedient if the cross-sectional shape of the inner rib 51 is the same over a length of at least 50% of the total length of the inner rib 51, such as over a length of at least 60% or of at least 65%. This greatly reduces the tendency of the sealing element 20 towards a subsequent axial offset.

[0135] In this way, it is possible to maintain the necessary minimum pressing force for closing the opening 34. Thus, a closure cap 10 is made available in which the axial distance between the outer stop 11 and the inner stop of the closure cap measures 2.85 mm with a tolerance of +/0.2 mm, such as of +/0.1 mm or of +/0.05 mm. In this way, the required minimum pressing force for sealing the opening 34 is safely maintained.

[0136] Moreover, it is particularly expedient if the actuating portion 50 comprises elongate outer ribs 53 which are arranged axially in their main extent and protrude radially outwards from the circumferential surface, said outer ribs 53 offering a user a better grip and thus making screwing and unscrewing easier. In the example, the actuating portion 50 comprises eight such outer ribs 53. These outer ribs 53 extend along almost the entire length of the actuating portion 50. In some embodiments, these outer ribs have a length, i.e. an extent in the axial direction, of at least 4.5 mm, such as of at least 5.0 mm. In the example, the length is approximately 5.3 mm, which already affords a sufficient grip surface.

[0137] The height of these outer ribs 53, i.e. the radial protrusion from the circumferential surface, is at least 0.3 mm, such that the user is provided with a stable grip surface and can thus open the closure piece more efficiently and more easily.

[0138] The closure piece 1 is made of a color-stable plastic. In order to color the plastic, the pigments listed below are used as elements for providing color: [0139] titanium dioxide Kronos 2233 [0140] carbon black PRINTEX F 85 [0141] 6975 titanium orange [0142] VYNAMON Green 600734.

[0143] A closure piece 1 made of such a material is therefore also suitable for sterilization methods performed with gamma rays or X-rays. It has been found that such closure pieces, when exposed to radiation at an energy dose in a range of 25-40 kGy, do not lead to any color changes, or any color changes readily perceptible to the human eye, and can therefore be regarded as being color stable.

[0144] A material composition of this kind is also suitable for other sterilization methods, for example steam sterilization at up to 134 C. for a period of 10 minutes, which does not lead to any color changes, or any color changes readily perceptible to the human eye.

[0145] While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.

LIST OF REFERENCE SIGNS

[0146] 1 closure piece [0147] 10 closure cap [0148] 11 stop [0149] 12 outer edge of the closure cap [0150] 13 outer edge of the closure cap [0151] 14 cavity [0152] 15 shoulder [0153] 16 stop [0154] 20 sealing element [0155] 21 sealing portion [0156] 22 outer edge of the sealing portion [0157] 23 outer edge of the sealing portion [0158] 24 inner edge [0159] 25 recess [0160] 30 container [0161] 31 sleeve [0162] 33 tip [0163] 34 opening [0164] 35 chamber [0165] 36 collar [0166] 40 mounting portion [0167] 41 outer thread [0168] 42 rib [0169] 44 bulge [0170] 45 free space [0171] 46 thread entry [0172] 47 bevel [0173] 50 actuating portion [0174] 51 inner rib [0175] 52 insertion bevel [0176] 53 outer rib [0177] 100 closure piece [0178] 110 closure cap [0179] 112 outer edge of the closure cap [0180] 120 sealing element [0181] 121 sealing portion [0182] 122 outer edge of the sealing portion [0183] 140 mounting portion [0184] 150 actuating portion [0185] S settling [0186] A distance [0187] E injection point