A METHOD AND A DEVICE FOR SILICONISING RUBBER STOPPERS

Description

[0001] The present invention relates to a method of treating rubber stoppers intended to seal packages containing sterile products, for instance medicinal preparations.

[0002] In sealing packages in the form of test tubes containing medicinal preparations it is important to prevent sterilised preparations that are contained in the packages from being contaminated during the very package-sealing process. In this connection rubber stoppers are used in order to stop such test tubes. The stoppers are initially subjected to washing and rinsing treatments, followed by sterilisation and drying. Prior to the sterilisation step the stoppers are also treated with silicone to ensure that they do not adhere to one another when stored after the sterilisation step, but also to make the stoppers sufficiently pliable for convenient application to the test tubes one by one and for efficient sealing of the tubes.

[0003] In accordance with a previously known method washed stoppers are deposited on a vibrating table, known as a shaker. A mist of silicone is sprayed onto the stoppers which are subsequently collected in containers or bags in which they are sterilised in an autoclave.

[0004] In accordance with another prior-art method a thin silicone oil is mixed with water and an emulsifying agent is added to promote mixing. Thus, an emulsion is formed which is pumped into a container holding stoppers therein. The stoppers are siliconised, sterilised, and dried inside the container. A method to siliconise devices using an emulsion of silicone oil and water together with an emulsifying agent is described in for example EP-0403400 and EP-0364375.

[0005] The latter method is advantageous compared with the first-mentioned method inasmuch as it is more convenient to put into practice. From an environmental aspect this latter method is, however, disadvantageous in that it requires the addition of a chemical substance for the emulsion to be produced.

[0006] The object of the present invention is to provide a method of forming an emulsion from silicone and water without having to resort to the addition of any chemical substances, which emulsion may be used to efficiently siliconise rubber stoppers. This object is achieved by means of the inventive method according to which silicone oil and water alone are mixed while being stirred with sufficient vigour to produce an emulsion, and the resulting emulsion is directed to a container in which the stoppers are stored and the siliconising process is carried out.

[0007] The invention likewise concerns a device for performing the method. The features characterising the device are defined in the appended claims 3 and 4.

[0008] The invention will be described in more detail in the following with reference to the accompanying drawing which is a schematic representation of the inventive device.

[0009] A dosage pump 4 is installed in a conduit 1 leading from a vessel 2 holding silicone oil 3. Downstream from the dosage pump 4 a shut-off valve 5 is mounted in the conduit 1. The conduit 1 branches into a water-supply conduit 6 in which is likewise mounted a shut-off valve 7. Water supplied via the conduit 6 is mixed with dosed amounts of silicone oil 3 that are discharged from the pump 4 and transported through the conduit 1. Downstream from the junction 8, where conduit 1 branches into conduit 6, a dispersing pump 9 is provided, and in a conduit 10 leading from pump 9 to a container 11 for storage of rubber stoppers to be siliconised are mounted a further shut-off valve 12 and a throttle valve 13.

[0010] The method in accordance with the invention is carried out in the following manner. Water and silicone oil 3 in the desired proportions are pumped into the pump 9. The dispersion carried out therein is sufficiently vigorous to produce an emulsion independently of whether the silicone oil is a high-viscosity or a low-viscosity oil. The emulsion is then pumped into the container 11 wherein a mixture 14 of emulsion and rubber stoppers is formed. Siliconising of the rubber stoppers thereafter takes place, as a result of which the stoppers receive a thin silicone coating.

[0011] In accordance with a further development of the method according to the invention, air is blown into the mixture 14 of emulsion and stoppers, resulting in the emulsion (the silicone) adhering so well to the surface of the stoppers that the residue liquid essentially will consist exclusively of water. This water is drained off. In an already known manner, vapour is supplied to the container to sterilise the stoppers which are subsequently dried. The container may then serve as a stopper storage means where the stoppers may be kept until they are to be used.

[0012] The throttle valve 13 is provided to allow variable throttling of the flow to the container 11. In this manner it becomes possible to regulate the emulsion mixing time inside the dispersing pump 9 in order to obtain optimum dispersing results.

Claims

1. A method of treating rubber stoppers intended to seal packages containing sterile products, for instance medicinal preparations, by washing, rinsing and thereafter siliconising said rubber stoppers in an emulsion of silicone oil and water, followed by sterilisation and drying, characterised by mixing silicone oil and water in a dispersing pump (9) under stirring to produce an emulsion, and feeding the resulting emulsion through a throttle valve (13), which is arranged to regulate the emulsion mixing time, in said dispersing pump (9), to a container (11) in which the stoppers are stored and the siliconising process is carried out.

2. A method as claimed in claim 1, characterised by blowing air into the mixture (14) of emulsion and stoppers to promote siliconisation of the latter.

3. A device for performing the method according to claim 1 of treating rubber stoppers intended to seal packages containing sterile products, for instance medicinal preparations, characterised in that the device comprises a first pump (4) arranged to pump dosed amounts of silicone oil to a water conduit (6), and a second pump(9) arranged to form, under dispersing action, an emulsion from the amounts of silicone oil and the water flowing through the water conduit (6), and to pump the resulting emulsion to a container (11), in which the stoppers are stored, for the purpose of siliconising said stoppers inside the container (11) wherein a throttle valve (13) is arranged in the path of flow from the dispersing pump (9) to the container (11) in order to regulate the emulsion mixing time inside the dispersing pump (9).

Ansprüche

1. Verfahren zur Behandlung von Gummistopfen, die sterile Produkte, zum Beispiel medizinische Präparate, enthaltende Packungen verschließen sollen, indem die Gummistopfen gewaschen, gespült und dann in einer Emulsion von Silikonöl und Wasser silikonisiert und danach sterilisiert und getrocknet werden, dadurch gekennzeichnet, daß Silikonöl und Wasser unter Rühren in einer Dispergierpumpe (9) zur Erzeugung einer Emulsion vermischt und die entstehende Emulsion durch ein zur Regulierung der Emulsionsmischzeit in der Dispergierpumpe (9) angeordnetes Drosselventil (13) einem Behälter (11) zugeführt werden, in dem die Stopfen gelagert sind und der Silikonisierungsprozeß durchgeführt wird.

2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß man Luft in die Mischung (14) aus Emulsion und Stopfen bläst, um die Silikonisierung der letzteren zu fördern.

3. Vorrichtung zur Durchführung des Verfahrens nach Anspruch 1 zur Behandlung von Gummistopfen, die sterile Produkte, zum Beispiel medizinische Präparate, enthaltende Packungen verschließen sollen, dadurch gekennzeichnet, daß die Vorrichtung eine erste Pumpe (4), die zum Pumpen dosierter Mengen von Silikonöl zu einer Wasserleitung (6) angeordnet ist, und eine zweite Pumpe (9) umfaßt, die zur Bildung einer Emulsion aus den Mengen von Silikonöl und durch die Wasserleitung (6) fließendem Wasser unter Dispergierwirkung und zum Pumpen der entstehenden Emulsion zu einem Behälter (11), in dem die Stopfen gelagert sind, zwecks Silikonisierung der Stopfen in dem Behälter (11) angeordnet ist, wobei im Strömungsweg von der Dispergierpumpe (9) zum Behälter (11) ein Drosselventil (13) angeordnet ist, um die Emulsionsmischzeit in der Dispergierpumpe (9) zu regulieren.

Revendications

1. Procédé pour traiter des bouchons en caoutchouc destinés a rendre étanches des conditionnements contenant des produits stériles, par exemple des préparations médicales, par lavage, rinçage et traitement ultérieur au silicone desdits bouchons en caoutchouc dans une émulsion d'huile de silicone et d'eau, et ensuite par stérilisation et séchage, caractérisé par le fait de mélanger l'huile de silicone et l'eau dans une pompe de mise en dispersion (9) sous agitation pour produire une émulsion, et par le fait d'alimenter l'émulsion résultante, à travers une soupape d'étranglement (13) qui est arrangée pour réguler le temps de mélange de l'émulsion dans ladite pompe de mise en dispersion (9), à un récipient (11) dans lequel les bouchons sont entreposes et dans lequel le processus de traitement au silicone est mis en oeuvre.

2. Procédé selon la revendication 1, caractérisé par le fait de souffler de l'air dans le mélange (14) de l'émulsion et des bouchons pour favoriser le traite- ment au silicone de ces derniers.

3. Dispositif pour la mise en oeuvre du procédé selon la revendication 1 de traitement de bouchons en caoutchouc destines a rendre étanches des conditionnements contenant des produits stériles, par exemple des préparations médicales, caractérisé en ce que le dispositif comprend une première pompe (4) arrangée pour pomper des quantités dosées d'huile de silicone en direction d'un conduit pour l'eau (6), et une deuxième pompe (9) arrangée pour former, sous une action de mise en dispersion, une émulsion a partir des quantités d'huile de silicone et d'eau s'écoulant a travers le conduit pour l'eau (6) et pour pomper l'émulsion résultante en direction d'un récipient (11) dans lequel les bouchons sont entreposes, dans le but de traiter au silicone lesdits bouchons a l'intérieur du récipient (11), dans lequel une soupape d'étranglement (13) est arrangée dans la voie d'écoulement s'entendant entre la pompe de mise en dispersion (9) et le récipient (11) dans le but de réguler le temps de mélange de l'émulsion à l'intérieur de la pompe de mise en dispersion (9).

Drawing