Food packaging

Abstract

Food packaging (10) comprising a plate-shaped, semi-rigid hollow-chamber sheet as a base (14) for the food, extruded from food-certified polypropylene (PP) and food-certified talc, corona-treated at least on the contact surface for the food and printed with food-safe ink, and having a total thickness between 1.5 mm and 3 mm.

Description

The present invention relates to a food packaging comprising a plate-shaped, semi-rigid hollow chamber sheet as a base for the food. Food packaging comes in a wide variety of designs, each adapted to the specific food product. Hollow-chamber plastic sheets are a suitable packaging material due to their low weight, high stability and durability, and good food compatibility. They consist of two parallel walls connected by ribs, which divide the space between the two walls into numerous hollow chambers. From EP 0 339 593 a hollow chamber twin-wall sheet made of plastic is known, which is used as wall material for containers for food. JP 2008 155952 A shows box-shaped food containers whose walls are formed by hollow-chamber twin-wall sheets made of plastic. Packaging for certain food products, such as smoked fish, consists of a flat base covered by a transparent film. The weight of such packaging and the amount of material used in its production are low. The base is usually made of cardboard. However, this requires special treatment for use in food packaging, and its stability is limited. Furthermore, there is a need for a more premium appearance for the packaging in order to present high-priced food products attractively. The well-known hollow-core sheets, as used in the aforementioned prior art, are unsuitable for this application due to their properties. The object of the invention is therefore to create a food packaging for the aforementioned purpose which has a high-quality appearance while being lightweight, highly stable and durable, having good food compatibility and requiring little material. This problem is solved according to the invention by a food packaging which comprises a plate-shaped, semi-rigid hollow chamber sheet as a base for the food, which is extruded from food-certified polypropylene (PP) and food-certified talc, corona-treated at least on the contact surface for the food and printed with food-safe ink and has a total thickness between 1.5 mm and 3 mm. Despite its relatively thin profile, the base of the food packaging according to the invention exhibits high rigidity, making it resistant to mechanical damage. It consists entirely of food-grade materials and gives the packaging an attractive and high-quality appearance, to which the printing on the base contributes. Talc is added to the polypropylene to improve the rigidity of the multiwall sheet. The corona treatment is a plasma coating that prepares the printing surface while simultaneously killing viruses, bacteria, and spores. Advantageous embodiments of the invention are specified in the dependent claims. In one embodiment, the hollow-chamber multiwall sheet has micropores in its two parallel walls, which are connected by webs. This achieves a certain degree of air permeability and breathability. Preferably, the micropores have a diameter of 1.0 mm or less, preferably a diameter of 0.2 mm. The pores can, for example, be arranged in a square grid with a pore spacing on the order of about 3 to 5 mm. For example, the hollow-chamber multiwall sheets can initially be manufactured from plastic using an extrusion process without micro-perforation. In a further step, the extruded profile is then passed through a gap between two perforation rollers, which create the micropores in the outer walls of the sheets. Preferably, the food packaging comprehensively comprises a cover that is held against the base and covers the food. The following section explains an exemplary embodiment in more detail with reference to the drawing. Figure 1 shows a perspective view of an embodiment of the food packaging according to the invention; and Figure 2 shows an enlarged section along line II-II in Figure 1. Figure 1 shows a food packaging 10, for example for smoked salmon 12, which has a plate-shaped base 14 and a film-like cover 16. The base 14 is formed by a micro-perforated hollow-chamber sheet and has a rectangular shape with rounded corners. Fig. 2 shows an enlarged partial section through the hollow-chambered sheet that forms the base 14. The sheet has two parallel walls 18, one of which (here: the wall 18 located on the top side of the sheet) forms the support surface for the food, in this case, the fish. The walls 18 are connected to each other at regular intervals by webs 20, which are made of the same material and connect to the walls 18, dividing the space between these walls into a series of hollow chambers 22 with, for example, a square cross-section. Within each hollow chamber 22, the two walls 18 each have at least one row of micropores 24. In this example, the micropores have a diameter of approximately 0.2 mm. The hollow chamber sheet is manufactured from food-grade polypropylene (PP) and food-grade talc using an extrusion process and, after extrusion, is corona-treated at least on the contact surface and printed with food-safe ink. The total thickness of the multiwall sheet is between 1.5 mm and 3 mm, so that the sheet is as thin as cardboard, yet still as flexible as cardboard despite the reinforcement provided by the ribs. QUOTES INCLUDED IN THE DESCRIPTION This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature EP 0 339 593

[0003] JP 2008 155952 A

[0004]

Claims

Food packaging (10) comprising a plate-shaped, semi-rigid hollow-chamber sheet as a base (14) for the food, extruded from food-certified polypropylene (PP) and food-certified talc, corona-treated at least on the contact surface for the food and printed with food-safe ink, and having a total thickness between 1.5 mm and 3 mm. Food packaging according to claim 1, wherein the hollow chamber grid plate has micropores (24) in its two parallel walls (18) connected by webs (20). Food packaging according to claim 2, wherein the micropores (24) have a diameter of 1.0 mm or less, preferably a diameter of 0.2 mm. Food packaging (10) according to one of the preceding claims, comprising a cover (16) held on the base (14) and covering the food.

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