Shrinking protective wrapping or film.

Shrinkable protective hood or film

Skyddshuva eller -film med krympförmäga

The invention relates to a shrinkable protective hood or film for pallet or group packages.

Shrinkable protective hoods or films are used in so-called in group packaging, such as sacks or the like, and in pallet packaging to protect the packaging. When the packages are protected, e.g., by a protective hood, which is shrunk by conventional techniques, such as, for example, by heat or radiation around the packages, in the currently used protective peaks, their inner surface adheres to the packages to be protected. If the protective hood is removed later, there is a high risk of damage to the packaging.

The problem described above has previously been eliminated by placing, for example, a sheet of paper between the packages to be protected and the protective hood, whereby the protective hood does not adhere to the packages. Another known solution is the so-called a double hood solution in which the inner hood does not stick to the packages because it does not shrink under normal conditions of use. In such a solution, a conventional shrinkable protective hood is used as the outer hood.

Both of the known solutions described above have the disadvantage of a complicated packaging method, which is also an uneconomical solution in terms of material consumption and working time used for packaging.

A solution is also known in which either the protective hood or the plastic bags to be packed are selected from such materials that either the density of the material used in the protective hood is lower than the density of the material used in the plastic bag or the material used in the plastic bags is lower than the density of the protective hood material. Even in this solution, the disadvantage is still that the materials can stick to each other despite the fact that the materials have different densities.

A solution is also known in which a protective hood is formed. yhdistelmäkalvosta. The inner surface of such a composite film is, for example, polypropylene.

The disadvantage of this known solution is the inconvenience of the required shrinkage and its control.

It is an object of the invention to provide an improvement over the currently known shrinkable protective hood or membrane solutions. It is a more specific object of the invention to provide a shrinkable protective hood or film in which adhesion of the protective hood or film to the products to be protected, such as packages or the conventional protective hood surrounding the group package, is reliably avoided.

The objects of the invention are achieved by a shrinkable protective hood or

characterized in that one surface of the protective hood or film is a shrinkable polyolefin film and the other surface is an amorphous plastic material or a mixture of amorphous plastic material and polyolefin which, when shrunk, does not adhere to the pallet or group package or the conventional protective package surrounding the group package.

In a preferred embodiment of the invention, the proportion of amorphous plastic material is between 50-100%, preferably between 70-100%.

As the amorphous plastic material, the following amorphous polymers can be used: polyamide, polycarbonate, polymethyl methacrylate, polystyrene, polyvinyl chloride, polyisobutene, polypropylene and polyethylene (atactic), polyethylene terephthalate, polyurethane, acrylonitrile-butadiene-styrene It should be noted that the polyethylene terephthalate polymer is both amorphous and non-amorphous.

In some applications, polystyrene and mixtures thereof have been found to be particularly preferred. One preferred amorphous mixture consists of 75% polystyrene and 25% butadiene.

The shrinkable protective hood or film according to the invention can be either a monofilament or a multilayer film.

The invention will be explained in detail with reference to some preferred embodiments of the invention shown in the figures of the accompanying drawings, to which, however, the invention is not intended to be exclusively limited.

Figure 1 schematically shows a preferred embodiment of a shrinkable protective hood according to the invention applied to the protection of a group package consisting of sacks.

Figure 2 is a cross-sectional view of a preferred embodiment of the shrinkable protective hood material used in Figure 1.

Figure 3 is a cross-sectional view of another preferred embodiment of the shrinkable protective hood material used in Figure 1.

Figure 4 schematically shows a group package in which the products are packed with a shrinkable protective film according to the invention and the group package is protected by a conventional protective hood.

Figure 5 shows a cross-section of a preferred embodiment of the shrinkable protective film material used in Figure 4.

Figure 6 is a cross-sectional view of an alternative embodiment of the shrinkable protective hood used in Figure 1 or the shrinkable protective film material used in Figure 4.

In the embodiment according to Figures 1 and 2, the shrinkable protective hood according to the invention is generally indicated by the reference number 10. In this embodiment, the products 13 to be protected, such as, for example, sacks form a so-called group package. The sacks 13 are protected by a shrinkable protective hood 10 according to the invention, which is shrunk by a conventional technique. The second surface of the protective hood 10, in this embodiment the outer surface 12, is a conventional shrinkable plastic material and the second surface, in this embodiment the inner surface 11, an amorphous plastic material or a mixture of amorphous plastic material and polyolefin which does not adhere to the packages 13 to be protected.

The embodiment shown in Fig. 3 is otherwise the same, but the protective hood 10 consists of a three-layer film in which the outer surface 12 is a conventional shrinkable plastic material and the inner surface 11a is an amorphous plastic material or a mixture of amorphous plastic material and polyolefin which does not adhere to

In the embodiment of Figures 4 and 5, the products to be protected, such as bottles 113 used in the pharmaceutical industry, are protected by shrinkable protective films 100 according to the invention. The products 113 protected by the protective films 100 form a group package surrounded by a conventional protective hood 114. In this embodiment, the inner surface 111 of the protective film 100 is a conventional shrinkable plastic material and the outer surface 112 is an amorphous plastic material or a mixture of amorphous plastic material and polyolefin which, when shrunk, does not adhere to the conventional protective hood 114 surrounding the group package.

The embodiment shown in Fig. 6 is otherwise the same as the embodiment shown in Figs. The monofilm 12 'according to Fig. 6 can of course also be applied to the protective film used in the embodiment according to Fig. 4 as a protective film 100' consisting of a monofilm 112 '.

Only some preferred embodiments of the invention have been described above, and it will be clear to a person skilled in the art that numerous modifications can be made to them within the scope of the inventive idea set out in the appended claims.