HK40013886A - Prefilled syringe - Google Patents

Description

Drug-loaded syringe

The invention relates to a divisional application of an invention patent application with the international application date of 09 and 26 in 2013 and the name of 'drug-carrying injector', which is PCT/EP2013/070140, and the application number of a mother case entering China is 201380050444. X.

Technical Field

The invention relates to a pre-filled syringe comprising a syringe cylinder which is designed in an open manner and is closed with a plunger on one axial side and comprises a luer-lock connection on the other axial side, which is integrally formed on a face wall, at which the syringe ends and which is closed with a stopper.

Background

Such pre-filled syringes are increasingly used, in particular in medical treatment, and are filled with a flowable medium, i.e. usually a liquid or paste-like substance, such as a drug or contrast means. Ejection of this medium is achieved by inserting a plunger into the syringe barrel, by which means the medium exits through an opening in the luer cone of the luer lock connection. A stopper of soft elastic material is provided which closes at least the luer within the luer lock connection, thereby ensuring that the medium located in the syringe barrel does not escape from the luer lock connection before its use, and that the syringe barrel is closed hermetically, in particular protecting the syringe barrel from the ingress of germs. Thus, in particular for medical products, it is ensured that it is immediately possible to identify from the outside whether the stopper has been opened once. A tamper-evident closure is provided for this purpose and this includes a separating web which must be broken to access the stopper, in particular to remove it from the luer.

For syringe barrels made of glass, which are used almost exclusively for medical products, it is known to stick a tamper-evident closure made of plastic to a luer connection and a stopper closing the luer connection in a form-fitting manner at the end of the syringe barrel on the injection side (EP 0397951 a 1). The problem with such tamper-evident closures is that the closures must on the one hand be elastic so that they can be pushed past the bead on the discharge-side end of the syringe barrel in a retaining manner, but on the other hand the retaining connection has to be designed so that upon opening the tamper-evident closure breaks at a predefined breaking point and not the retaining connection is separated. This is very demanding for the manufacturing technique and requires a high precision of the manufacturing.

DE 10247965 a1 discloses a tamper-evident closure, and a syringe cylinder with the tamper-evident closure and a luer lock are designed as one-piece plastic injection-molded part, and on the other hand a stopper and a tamper-evident closure are connected to the syringe cylinder by a material-fit connection, which is further advantageous in this respect. The disadvantages of the design shown in this document are: first, the stopper must be manufactured as a separate component and must be attached to a tamper evident closure that is also manufactured as a separate component, at which time the unit thus formed is welded or bonded to the syringe barrel. After opening the tamper evident closure, a part of the closure always remains on the syringe side, due to even predefined breaking positions in the tamper evident closure, and this is disadvantageous for several reasons. Thus, on the one hand, the luer cannot be contacted at its outer edge and, on the other hand, a broken separating web always poses some risk of injury. Although it is conceivable in this document to design the weld between the syringe cylinder and the tamper-evident closure itself as a separating web as an alternative, it has been found that designing the weld as a separating web is also problematic and risks injury when the separating web is damaged.

Finally, the use of plastics in syringe barrels for pre-filled syringes in medical technology has not yet been demonstrated, which is why syringe barrels made of special glass are always used for high-purity products.

Disclosure of Invention

Against this background, it is an object of the present invention to provide a pre-filled syringe which to a large extent avoids the above-mentioned disadvantages, which is inexpensive to manufacture and reliable and safe to apply.

According to the invention, this object is achieved by a pre-filled syringe with the features defined in claim 1. Further advantageous developments of the syringe according to the invention can be gathered from the dependent claims, the following description and the drawings. The features specified in the dependent claims and in the description according to the invention, individually but also in suitable combinations, accordingly form further solutions according to claim 1 and according to the invention.

The pre-filled syringe according to the invention comprises a syringe cylinder which is designed open on one axial side and closed with a plunger, as is usual in such syringes, but comprises a luer lock connection on the other axial side, which luer lock connection is integrally formed on a face wall, at which the syringe cylinder ends, i.e. the luer lock connection is designed as a one-piece plastic injection-molded part together with the syringe cylinder and the face wall. The flowable medium located in the syringe is surrounded by the syringe cylinder, axially on one side by the plunger and on the other side by a face wall with a luer-lock connection and a soft plastic stopper, and can be paste, liquid or also gaseous, as the case may be. Thereby, the stopper sealingly closes at least the luer in the luer lock connection, i.e. the actual discharge cone. The outside of the plug is surrounded by a tamper-evident closure having a predetermined breaking point. The tamper-evident closure is designed to be made of the same type of plastic as the syringe cylinder or an equivalent type and is welded to the face wall of the syringe cylinder, wherein according to the invention the welded connection forms a predetermined breaking point and the stopper is incorporated into the tamper-evident closure. The flow of the contents of the syringe into the luer lock connection and specifically through the syringe barrel and through the face wall can be seen from the outside, since the syringe barrel is formed from a transparent plastic according to the invention. Preferably, but not necessarily, the tamper evident closure is likewise formed from a transparent plastic. In any case, it is formed from the same type or a similar type of plastic, thereby ensuring welding capability between the tamper evident closure and the face wall of the syringe barrel.

In this context, a face wall is to be understood as the entire area between the luer lock connection and the outer edge of the syringe cylinder. Optionally, the tamper evident closure may be aligned with or extend completely or partially out of the syringe barrel. The welding procedure can be carried out and controlled in a simple manner, even in large-scale manufacturing, due to the welding of the tamper-evident closure to the face wall of the syringe cylinder.

The considerable advantage of the design according to the invention is thus that no separating webs are provided as in the prior art, but that the welded connection itself forms the predetermined breaking point, which has the great advantage, in particular in combination with the transparent design of the components, that after detachment of the tamper-evident closure from the syringe, and thus also after removal of the welded connection or overcoming of the welded connection, an almost completely free projecting surface remains on the face wall of the syringe cylinder, and that this surface neither poses the risk of injury nor restricts the view of the interior of the syringe cylinder. Precisely, the latter is of great importance in the medical field, it being the latter that excludes air bubbles that are unintentionally carried along or that is only capable of checking the controlled discharge of the medium from the syringe cylinder into the luer lock connection by means of the observed controller.

Before opening the tamper-evident closure, the correct seating of the stopper and the integrity of the medium in the syringe cylinder can already be determined from the outside, which is advantageous in particular if the tamper-evident closure is likewise designed in a transparent manner. The solution according to the invention therefore represents a considerably lower cost solution than the prior art, i.e. until now also syringe cylinders made of glass; but at the same time represents a much more reliable and manageable solution than previous syringes made of plastic.

It is particularly advantageous if both the plug and the tamper-evident closure are manufactured by a 2K injection molding process. In this way, a stopper can be formed from a suitable, soft resilient, thermoplastic material and a tamper evident closure formed from a relatively hard plastic, similar to a syringe barrel. The 2K injection molding method is technically easy to manage and therefore represents an inexpensive possibility to manufacture two parts in an injection molding method in a manner similar to a single piece, the two parts themselves being independent of each other. Thus, the assembly of the stopper in the tamper evident closure is completed and removed, which means that the manufacturing costs of the pre-filled syringe can be further reduced.

According to an advantageous further development of the invention, the tamper-evident plug and the plug are physically connected to each other. This positive fit connection ensures that the plug is arranged with a positive fit in the tamper-evident closure and is therefore always handled together with the tamper-evident closure. This style of component provides the following advantages: the freedom of choice of materials for the stopper and the tamper-evident closure and for use with the 2K injection molding method is greater, since these do not require the formation of a material-fit connection nor any other adhesive connection, but in extreme cases can be connected to one another only by a substantial fit. The actual engagement between the plug and the tamper-evident closure is thereby advantageously formed externally and in the direction of rotation about the central longitudinal axis. By this arrangement it is ensured that the stoppers are always moved jointly when rotating and tilting the tamper-evident closure on the syringe and, thereby, are also reliably moved jointly and finally removed when breaking the predetermined breaking position, i.e. the welded connection between the tamper-evident closure and the face wall of the syringe cylinder. Since the tamper-evident closure peripherally surrounds the plug, considerable hand forces can be exerted on the plug by means of this tamper-evident closure in view of a suitable actual mating connection, so that even if the plug is firmly seated in the luer connection or luer-lock connection, the plug peripherally surrounds the luer connection at this time, nevertheless a simple release by hand forces is ensured.

The syringe cylinder with the integrated luer-lock connection and, as the case may be, the tamper-evident closure is advantageously formed from a polyolefin. Several combinations are known from this plastic family and these combinations meet the special requirements for the material of the pre-filled syringe, i.e. in particular are formed in a transparent manner, ensure a high dimensional stability at the time of injection molding and provide a large barrier with respect to the penetration of the medium stored in the syringe cylinder. An inexpensive plastic for the syringe barrel and the integrally formed luer lock connection or tamper evident closure is polypropylene. The syringe barrel may alternatively be constructed of a circular olefin copolymer or another suitable thermoplastic material.

The syringe barrel is usefully constructed of a shielding plastic, wherein the shielding feature is related to the loading medium.

The stopper is advantageously composed of a thermoplastic polymer and is more or less soft and elastic compared to the material of the syringe barrel. A particularly suitable material for this is thermoplastic polyurethane, which can be easily managed using injection moulding techniques, in particular 2K injection moulding techniques.

Drawings

The invention will be explained in more detail hereinafter by means of an embodiment example shown in the drawings. Shown is that:

fig. 1 is a highly simplified schematic view of the discharge-side end of a pre-filled syringe with a tamper-evident closure applied in longitudinal section; and

FIG. 2 is a section along section line A-A in FIG. 1.

Detailed Description

Only the discharge side part of the pre-filled syringe 1 is shown in fig. 1. This syringe comprises a longitudinally extending syringe cylinder 2 which is designed in an open manner at its axial end, which is not visible in fig. 1, and is closed by a stopper, which is likewise not shown and can be guided movably within the syringe cylinder 2. The syringe cylinder 2 is closed on the other axial side shown in fig. 1 by a face wall 3, on which a luer-lock connection 4 is integrally formed. The syringe cylinder 2, the face wall 3 and the luer lock connection 4 are designed as a one-piece plastic injection-molded part and consist of the materials initially and advantageously specified previously. The luer-lock connection 4 is constituted in a known manner by an internal luer cone 5, which corresponds to a conventional luer connection and comprises an internal through-channel 6 to the syringe cylinder 2. The luer connection 5 is surrounded by a cylindrical part 7, the cylindrical part 7 being internally threaded on its inner side and forming, together with the luer connection 5, the luer-lock connection 4 in a known manner.

The medium 8 located inside the syringe cylinder 2 is closed off hermetically at the periphery by the syringe cylinder 2, at the open axial side not visible in fig. 1 by a plug, and at the other axial side separated by the face wall 3 and the luer-lock connection 4 by a plug 9. The plug 9 consists of a soft elastic thermoplastic material and comprises a protrusion 10, the protrusion 10 being directed in a conical manner towards the through-channel 6 of the luer connection 5 and the protrusion 10 sealingly closing off the through-channel 6 from the outside. The annular portion 11 is connected to the projection 10 at a radial distance and this portion extends significantly beyond the projection 10 over its axial length. This annular portion 11 peripherally surrounds the luer cone 5 and thus forms an annular groove between the projection 10 and the annular portion 11, into which groove the free end of the luer cone 5 engages. The sealing is firstly achieved by the projection 11 which sealingly closes the free end of the through-channel 6 and, on the other hand, by the annular portion 11, the annular portion 11 sealingly bearing against the outer edge of the luer cone 5. The protrusion 10 and the annular portion 11 merge into a substantially cylindrical portion 12, through which portion 12 five radially extending webs 13 extend which extend outwards into the intermediate space 14.

In the region of the web 13 and the intermediate space 14, the plastic part forming the tamper-evident closure 15 passes through the plug 9. In addition to the parts projecting into the free spaces 13 and 14, this tamper-evident closure 15 also comprises an annular portion 16, which annular portion 16 surrounds the plug 9 up to near the axial end of the projection 10. The annular portion 16 is connected by a region interrupted by a plurality of recesses 17 arranged annularly to a radially widened annular portion 18, which annular portion 18 bears with its cylindrical inner diameter against the outer edge of the cylindrical portion 7 of the luer-lock connection 4 with little play and up to the face wall 3, which is welded thereto at a plurality of portions. The annular portion 18 thus extends in a tapering manner to the face wall 3 and comprises axially parallel ribs 19, thereby increasing the gripping ability of the portion.

As is evident in fig. 1, the annular portion 18 is not welded to the face wall 3 over the entire edge, but only over portions, similar to the arrangement of the recess 17 on the other axial side of the tamper-evident closure. Since the annular portion 18 is welded to the face wall 3 of the syringe cylinder 2 only in sections, a predetermined breaking point is formed between the two parts and this predetermined breaking point can be broken by hand force. The welded connection is thereby released, i.e. the face wall 3 retains almost its original appearance after opening the tamper-evident closure, i.e. it is also planar and smooth and substantially transparent, so that the interior of the syringe 1 and the loading medium 8 can be viewed through the transparent plastic of the syringe cylinder. Thus, after removal of the tamper evident closure 15, the injection/discharge area of the syringe 1 can be observed in particular and can thus be controlled optically in a simple manner. The surface of the face wall 3 is also smooth and substantially free of remnants of the tamper evident plugs 15.

The plug 9, which is not designed in a transparent manner in the present exemplary embodiment, is penetrated by the tamper-evident plug 15, the tamper-evident plug 15 likewise being formed from a transparent thermoplastic, so that it is ensured on the one hand that after assembly of this component the assembly consisting of the plug 9 and the tamper-evident plug 15 and produced by the 2K injection molding method always ensures correct placement of the plug 9 and on the other hand that removal and removal of the plug 9 when the welded connection is opened is ensured. It is clear that the materials forming the plug 9 and the tamper evident closure 15 do not have to form any kind of material-fit connection between each other, but that the actual fit inherent in the present design between these parts is sufficient to connect them to each other in a fixed, inseparable manner.

The parts of the stopper 9 and the tamper evident closure 15 manufactured with the 2K injection moulding method are designed such that when applying this part to the syringe, the inside of the ring-shaped portion 18 is guided on the outside of the cylindrical portion 7 of the luer lock connection 4, as shown in the sectional view in fig. 1. Firstly, the annular portion 18 is applied to the luer connection 5 by means of such a cylindrical guide, wherein the protrusion 10 is sealingly incorporated into the end of the through-channel 6 at the end stage of the assembly procedure. This guide ensures that the stopper 9 always closes the luer connection 5 in a defined manner. The tamper evident closure 15 is welded to the face wall 3 of the syringe by means of the annular portion 21, these weld portions also being able to be established in a simple manner with mass production due to the arrangement of the annular portion 21, since these areas are easily accessible. Such a manufacturing process can be monitored not only by visual control, but also by suitable other testing methods. Finally, in this exposed position of the syringe, it is immediately possible to recognize whether the tamper evident seal 15 has been broken, i.e. the welded connection is detached from the face wall 3. This is very easy to see, since the welding is not effected in the manner of a continuous edge, but only in the region of the face-side portion 21, so that a rotation about the central longitudinal axis 20 is usually effected upon removal and reattachment of the tamper evident closure 15, which rotation is visible at the face wall 3, since the welding position is now no longer aligned with the face-side portion 21.

List of reference numerals

1 Syringe

2 Syringe Cylinder

3 walls

4 luer Lock connection

5 luer taper, luer connection

6 through channel

7 cylindrical part

8 Loading Medium

9 plug

10 projection

11 annular part

12 cylindrical part

13 web

14 intermediate space

15 tamper evident closure

16 annular part

17 recess

18 annular part

19 Ribs

20 median longitudinal axis

21 face side part.

Claims (11)

1. A pre-filled syringe with a syringe cylinder (2), the syringe cylinder (2) being designed in an open manner and being closed with a plunger on one axial side and the syringe cylinder (2) comprising a luer lock connection (4) on the other axial side, the luer lock connection (4) being integrally formed on a face wall (3), the face wall (3) separating the syringe cylinder (2); with a flowable medium (8) loaded in the syringe cylinder (2); with a soft elastic stopper (9) that closes at least the luer (5); and with a tamper-evident closure (15) which surrounds the outside of the stopper (9) and has a predetermined breaking point, wherein the syringe cylinder (2), the face wall (3) and the luer-lock connection (4) are designed as a one-piece transparent plastic injection-molded part, the tamper-evident closure (15) being formed from the same type or a similar type of plastic as the syringe cylinder (2) and being welded to the face wall (3) of the syringe cylinder (2), wherein the welded connection forms the predetermined breaking point and the stopper (9) is incorporated into the tamper-evident closure (15), wherein the tamper-evident closure (15) comprises a ring-shaped portion (16), which ring-shaped portion (16) surrounds the stopper (9), which ring-shaped portion (16) is connected to the ring-shaped portion (18) by an area interrupted by a plurality of recesses (17) arranged annularly, the annular portion (18) is welded to the face wall (3).

2. The pre-filled syringe according to claim 1, wherein the stopper (9) and the tamper evident closure (15) are manufactured by a 2K injection moulding process.

3. A pre-filled syringe according to claim 1 or 2, wherein the tamper evident closure (15) and the stopper (9) are physically connected to each other.

4. The pre-filled syringe according to any one of the preceding claims, characterized in that the tamper evident closure (15) is designed in a transparent manner.

5. The pre-filled syringe according to any one of the preceding claims, wherein a substantial fit between the stopper (9) and the tamper evident closure (15) is made to the outside and in the direction of rotation about the middle longitudinal axis 20.

6. The pre-filled syringe according to any of the preceding claims, wherein the syringe barrel (2) is comprised of a polyolefin.

7. The pre-filled syringe according to claim 5, wherein the syringe cylinder (2) is comprised of polypropylene.

8. The pre-filled syringe according to any of the preceding claims, wherein the syringe barrel (2) is comprised of a circular olefin copolymer.

9. The pre-filled syringe according to any of the preceding claims, wherein the syringe cylinder (2) is made of a shielding plastic, the shielding features of which match the filling medium (8).

10. The pre-filled syringe according to any one of the preceding claims, wherein the stopper (9) is composed of a Thermoplastic Polymer (TPE).

11. The pre-filled syringe according to any of the preceding claims, wherein the stopper (9) is comprised of Thermoplastic Polyurethane (TPU).