WO2002069698A1

WO2002069698A1 - Antibacterial polymeric material for milk handling component

Info

Publication number: WO2002069698A1
Application number: PCT/SE2002/000324
Authority: WO
Inventors: Nils ÄLVEBY; Martin Bellander
Original assignee: DeLaval Holding AB
Current assignee: DeLaval Holding AB
Priority date: 2001-03-01
Filing date: 2002-02-25
Publication date: 2002-09-12
Anticipated expiration: 2003-09-01
Also published as: SE0100702D0; WO2002069698A8; SE0100702L

Abstract

The present invention refers to a component (2, 3, 7) to be included in a milk-handling device. The component (2, 3, 7) is at least partly manufactured in a polymeric material. The polymeric material is arranged to be in contact with milk at least during an operational state of the milk-handling device. Particles are embedded in the polymeric material and that said particles include silver.

Description

Antibacterial polymeric material for milk handling component.

A component

BACKGROUND OF THE INVENTION AND PRIOR ART

The present invention refers to a component to be included in a milk-handling device, wherein the component is at least partly manufactured in a polymeric material, and wherein the polymeric material is arranged to be in contact with milk at least during an operational state of the milk-handling device.

GB 883 448 discloses such a component in the form of a teatcup liner for a teatcup of a milk-handling device. The teatcup liner is designed to have a microbicidal effect in order to prevent bacterial growth or reduce the bacterial count on the surface of the teatcup liner. Such a microbicidal effect is obtained according to the teachings of this document by a phenolic agent dispersed through the teatcup liner. The phenolic agent may include orthophenylphenol . The teatcup liner is made of natural or synthetic rubber. As an alternative, this document also briefly mentions silver salts, for instance silver chloride, as a microbicidal agent.

In order to reduce the bacterial growth on different components being in contact with milk, it is also known to sterilise the components regularly. However, such a sterilising operation is time-consuming and therefore expensive. The new polymeric materials, such as silicon rubber, which have been developed, have an improved quality, i.e. they can be replaced after a much longer operational time period than previously employed rubber components of natural or synthetic rubber. Because of this improved quality, the problem of the growth of different micro-organisms has increased. As a consequence, sterilising of the rubber components on a regular basis is now necessary and may even be prescribed by law in some countries.

US 4,775,585 discloses a polymer article containing zeolite particles on which metal ion having a bactericidal property, for instance silver, is provided by an ion exchange reaction. The polymer article is produced by admixing zeolite particles previously provided with the metal ion with a polymer or by moulding a zeolite-containing polymer into an article and thereafter treating the article with a metal ion solution.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an improved solution to the problems discussed above. In particular, it is aimed at a polymer milking component, which prevents growth of micro-organisms.

This object is obtained by the component initially defined, which is characterised in that particles are embedded in the polymeric material and that each of said particles include a carrying body and silver connected to said body. Silver has a bacteriostatic, a bactericidal and a fungicidal effect and is therefore efficient in reducing growth of micro-organisms or even reducing the number of micro-organisms present on a surface of the polymer component. By including silver in particle bodies, the active silver may be distributed uniformly in a convenient manner in the polymeric material. Preferably, the particles are inorganic.

According to an embodiment of the present invention, silver is located on the surface of said particle bodies. By this embodiment, a relatively small amount of silver may be employed in relation to the microbicidal effect obtained. By disposing silver on the surface of the particle bodies, a relatively large surface area of silver may be obtained by a relatively small amount of silver. It is the silver present on the surface which constitutes the microbicidal or fungicidal agent.

According to a further embodiment of the present invention, said particles include metallic silver or silver ions . In particular, silver ions may be chemically bounded to said particle bodies .

According to a further embodiment of the invention, said particle bodies are formed by zeolites. Zeolites are known particles which have a large surface.

According to a further embodiment of the present invention, said particle bodies are formed by soluble glass bodies. Glass can include silver in the bodies, wherein silver is released when glass is dissolved by water or moisture reaching the glass body in the polymeric material or when the glass body is present at the surface of the polymeric material component .

According to a further embodiment of the present invention, said particles include an alloy including silver as a significant alloying element.

According to a further embodiment of the present invention, silver is slowly released from said particles bodies. According to a further embodiment of the present invention, said particles are in the form of a powder, i.e. relatively small particles. Preferably, the size of the particles is in the order of a few micrometers, especially 0,6 to 2,5 micrometers .

According to a further embodiment of the present invention, said particles are homogeneously distributed in the polymeric material. In such a way, the microbicidal effect may be ensured throughout the whole component. By this feature, the component may also be manufactured in an easy manner by conventional rubber-forming methods .

According to an advantageous application of the present invention, the component is a teatcup liner. Thanks to the microbicidal effect of the polymeric material of the teatcup liner, the quality of the milk may be maintained at a high level and at the same time the risk of infections of the teats of the animal may be reduced. According to a further application of the present invention, the component is a milk-conveying hose or a claw. For instance, the component may be utilised for the short milk conduit or the long milk conduit in a milk-handling device.

According to a further embodiment of the present invention, the polymeric material is a rubber-like material, which substantially consists of silicon rubber.

According to a further embodiment of the present invention, the polymeric material includes at least 0,5 weight percent of said particles . Preferably, the polymeric material includes 10 weight percent or less of said particles. Consequently, the microbicidal particles constitute a relatively small part of the polymeric material. When silver is applied, for instance onto the surface of the particles, the quantity of silver in relation to the particles is also significantly small. Consequently, a very small amount of silver is needed for the production of component according to the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is now to be explained more closely by the description of different embodiments thereof and with reference to the drawings .

Fig 1 discloses schematically a milk-handling device having components according to the present invention. Fig 2 discloses a teatcup with a teatcup liner.

DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE PRESENT INVENTION

Fig 1 discloses a part of a milk-handling device including four teatcups 1 to be attached to the teats of an animal to be milked. The teatcups 1 are connected to a claw 2 via a respective short milk conduit 3. The claw 2 provides an inner space for receiving the milk from the teatcups 1. The claw 2 is connected to a milk-collecting member 4 via a long milk conduit 5. A vacuum pump 6 is, in the embodiment disclosed, connected to the milk-collecting member 4 for providing a vacuum or low pressure to the inner space of the claw 2 and the interior of the teatcups 1 in a conventional manner. Thus, milk is sucked from the teats to the milk- collecting member 4 via the teatcups 1, the short milk conduits 3, the claw 2 and the long milk conduit 5.

Each teatcup 1 includes a teatcup liner 7, which is disclosed more closely in Fig 2. The teatcup liner 7 disclosed in Fig 2 forms an integral part with the short milk conduit 3. The teatcup liner 7, the short milk conduit 3 and the long milk conduit 5 are manufactured in a polymeric, rubber-like material, preferably silicon rubber. The claw 2 may be manufactured in a polymeric, plastic material. Fig 2 also discloses a short pulse hose 8 and a portion of a long pulse hose 9, which are connecting a pulsating chamber 10 of each teatcup 1 to a pulsator (not disclosed) .

In order to obtain a bacteriostatic or bactericidal effect to the rubber parts 3, 5, 7 and/or the plastic parts 2, 4 conveying the milk, particles are embedded in the polymeric material and each of said particles includes a carrying body and silver connected to said body. The particle bodies may be in a solid or a liquid state. The particle bodies form a matrix for the silver. The particle bodies may be formed by zeolite particles, which thus may support the microbicidal silver. Zeolites are natural or synthetic aluminosilicates, which may bond chemically silver ions. Also the hoses 8 and 9 may be manufactured in a polymeric material including such silver-containing particles .

The zeolite particles are present in the form of a fine powder. The average size (diameter) of each particle is in the order of one or a few micrometers, especially 0,6 to 2,5 micrometers .

The particle bodies may also be formed by glass bodies including silver ions. Glass has a capability to retain metal ions. The glass is preferably made soluble so that silver ions are slowly released from the bodies to provide the microbicidal effect in the polymeric material.

Possibly, metallic silver may also be supported by the carrying zeolite body. The invention is not limited to zeolite particles or glass particles, but also other particles supporting silver ions or metallic silver may be employed. It is also possible to provide an alloy including silver as a significant alloying element in or on said carrying particle bodies.

Zeolites have a skeleton structure providing small cavities which may be utilised for containing microbicidal silver.

The particles are homogeneously distributed in the polymeric material. Preferably, the particles are mixed into the polymeric material before forming, for instance by extrusion, to a teatcup liner 7, a milk-conveying hose 3, 5, a claw 2 or any other milking component manufactured in any natural or synthetic rubber material or in any soft or hard plastic material. In case the polymeric material is a plastic material, such as thermoplastic material, the particles may be introduced to the plastics in a melted condition.

The polymeric material may include a rather small percentage of the particles, for instance at least 0,5 weight percent up to 10 weight percent. More specifically, the polymeric material may contain 1, 2, 3, 4, 5, 6, 7, 8 or 9 weight percent of said particles .

The present invention is not limited to the embodiments disclosed but may be varied and modified within the scope of the following claims .

Claims

1. A component (2 - 5, 7) to be included in a milk- handling device, wherein the component (2 - 5, 7) is at least partly manufactured in a polymeric material, and wherein the polymeric material is arranged to be in contact with milk at least during an operational state of the milk- handling device, characterised in that particles are embedded in the polymeric material and that each of said particles includes a carrying body and silver connected to said body.

2. A component according to claim 1, characterised in that silver is located on the surface of said particle body.

3. A component according to any one of claims 1 and 2, characterised in that the particles include metallic silver or silver ions.

4. A component according to claim 3, characterised in that silver ions are chemically bonded to said particle bodies .

5. A component according to any one of claims 1 - 4, characterised in that said particle bodies are formed by zeolites.

6. A component according to any one of claims 1 - 4, characterised in that said particle bodies are formed by soluble glass bodies.

7. A component according to any one of claims 1 - 4, characterised in that said particles include an alloy including silver as a significant alloying element.

8. A component according to any one of the preceding claims, characterised in that silver is slowly released from said particles bodies.

9. A component according to any one of the preceding claims, characterised in that said particles are in the form of a powder.

10. A component according to any one of the preceding claims, characterised in that the size of said particles is in the order of a few micrometers, especially 0,6 to 2,5 micrometers .

11. A component according to any one of the preceding claims, characterised in that said particles are homogeneously distributed in the polymeric material.

12. A component according to any one of the preceding claims, characterised in that the component is a teatcup liner (7) .

13. A component according to any one of the preceding claims, characterised in that the component is a milk- conveying hose (3, 5) .

14. A component according to any one of the preceding claims, characterised in that the component is a claw (2) .

15. A component according to any one of the preceding claims, characterised in that the polymeric material is a rubber-like material, which substantially consists of silicon rubber.

16. A component according to any one of ^'the preceding claims, characterised in that the polymeric material includes at least 0,5 weight percent of said particles.

17. A component according to any one of the preceding claims, characterised in that the polymeric material includes 10 weight percent or less of said particles.