TRANSPORT PACKAGE

The present invention relates to a packaging material, and a transport package produced form the same.

Transport of hazardous goods, including medical samples, is subject to regulation. In particular security against leakage is called for. For the transport of diagnostic samples, including blood and urine, UN regulation 3373 (IATA 650) requires that the packaging must not leak when subject to a 95 KPA pressure drop.

Thus a transport package must be designed to minimise the possibility of breakage of the sample, and must also include sufficient absorbency to hold the entire contents of the sample, if a breakage or leaking does occur.

As a result, the manufacture of suitable packaging has required the amalgamation of multiple layers of materials, including layers for re-enforcement of the packaging and other layers to provide absorbency. Sometimes even more layers are included to provide an additional cushioning effect. As a result such packaging has often been complex and therefore expensive, requiring many stages in the manufacture. Furthermore, the packaging may be time-consuming and difficult for the user to assemble.

The object of the present invention is to provide a material including integrated absorbency, and a transport package using this material.

According to the invention there is provided a packaging material including:

• a first layer of thermoformable plastics material;

• a second layer including:-

• thermobondable material and • absorbent material.

Many types of absorbent material can be used and generally the type of absorbent material used will be chosen in accordance with the ultimate use of the material.

For use in absorbing large amounts of aqueous liquid, the absorbent material may be super-absorbent. Typically this will be in the form of fibres, but may also be in powder form. Alternatively, if less absorbency is required the absorbent material may be wood pulp. In addition a polypropylene based absorbent material sold under the name of "melt blown" can also be used, as this has the ability to absorb oil. Conveniently, combinations of absorbent material can be used.

Typically the absorbent material it will be used in quantities of 50% or more.

In one embodiment, the material will be a carded bi-component fibre including thermobonded fibres .

The thermobondable material and the absorbent material are mixed together and a fibre laying process is used bond the materials. This may either be an air laying process, a needle felting process or a carded thermobonding process. The application of heat to these fibres bonds the fibres together.

The two layers are then adhered together by thermoforming of the material into a product.

The first and second layers should be chemically compatible for optimum adhesion. Typically the first layer will be a polypropylene material having a sealable polyethylene coating and the thermobondable material being polypropylene fibre having a polyethylene outer coating. Alternatively, the thermobonable material may be polyethylene coated polyester.

According to a second aspect of the invention there is provided a transport package for transporting samples in holders, the package comprising:-

• a complementary pair thermoformed trays made from the material of the first aspect, and having indentations therein shaped for samples for transport;

• a gasket; and • a securing clip.

While the securing clip could be provided in several parts, preferably it is a single moulding, articulated for securing around the perimeter of the thermoformed trays.

Typically the trays will also be indented with ribs.

To help understanding of the invention, a specific embodiment thereof will now be described by way of example and with reference to the accompanying drawings, in which:

Figure 1 is a cross-sectional view of a sheet of packaging material according to the first aspect of the invention;

Figure 2 is a top view of a tray of material thermoformed in accordance with the second aspect of the invention and Figure 3 is a perspective view of the container using the sheet of Figure 2.

Referring to first to figure 1, the material 1 thereshown is a bi-layer material having a thermoformable layer 2 and an absorbent layer 4. The thermoformable layer is of a polypropylene material having a polyethylene coating, although other thermoformable materials could be used. The absorbent layer 4 comprises a mixture of a thermobondable fibres and absorbent material. Suitable thermobondable fibres sell under the OASIS trade mark and comprise of polypropylene fibres having a polyethylene coating. Other thermobondable fibres could also be used. The absorbent material is typically super-absorbent fibres. However other absorbent material, include super-absorbent powder, wood pulp or "melt blown" could be used.

The mixture is carded and then air laid, although other forms of mixing and heating could be used. On heating, during the air laying process, the outer coating of

the fibres melts and adheres all the fibres, including the absorbent material into a cohesive web.

The air laid web is then placed on to a thermoformable material for thermoforming.

Turning now to Figure 2, thereshown is a tray 10 of material described above, thermoformed to provide one half of a transport package. Depressions 12 having been thermoformed in the tray to provide spaces for samples to be transported. When this sheet is mated with a second complementary tray the samples will be entirely contained within the depressions. As shown the tray is thermoformed to hold five blood samples, but could equally be formed for urine or drug containers, or mixtures of these.

As the material is thermoformed, the heat of this process causes the polyethylene in the thermobondable fibres to again melt and to adhere to the thermoformable sheet. This results in a unifying of the two layers, and thus a material being impermeable to liquid, but absorbent on one side.

Ribs 14 are also thermoformed into the trays to provide additional stiffness in the package. In addition a depression 16 is thermoformed around the edge of the tray.

Now turning to Figure 3, the package thereshown 20 comprises two complementary trays 22, 24, captivating the samples with a gasket 26 provided in the depression therebetween. In use, samples are placed in the depression in a first tray, and a gasket is placed in the edge depression. A second tray is placed on top of the first sheet, trapping between the trays the samples and the gasket. To secure the package, a clip 28 is attached to the edge of the package. The clip is a moulding, which clips around the circumference of the package, over the gasket, sealing the container. As shown the clip comprises four separate clips, however these could be articulated to fit around the corners of the package.

Thus the transport package is both rigid to protect the samples and yet also absorbent to prevent leakage in the event of the failure of one of the sample holders

within the package. Super-absorbent material can typically hold up to forty-five times its own weight in liquid, and by incorporating 50% super-absorbent material in the absorbent layer in the package, the layer can absorb up to 80g/m of liquid. For use in a package designed to hold medical samples, this is sufficient absorbency to absorb any leaks. In addition, as the packaging is essentially translucent, it is easy to see whether there has been a leak, and this reduced the risk of handling the package.

The invention is not intended to be restricted to the details of the above- described embodiment. For instance, other plastics material can be used to prepare the absorbent sheet material.