The object of the invention is a non-cylindrical container (jar) made of plastic and intended for packing food products, in particular dry instant products.

There are known glass jars with non-cylindrical body, intended for packing, storage or warehousing of branded bulk products such as coffee, with two side walls that are concave inwards, making it easy to hold the packaging in the hand.

The disadvantage of these solutions is the material from which the containers are made - glass. High weight of glass, its fragility, risk of injury in contact with broken packaging (a particularly important factor for children and in places such as schools, swimming pools, stadiums). Therefore, in recent years, plastic packaging, which is free of fundamental defects of glass packaging, has become a leading type of packaging in the food industry.

There are known non-circular containers such as the one known from US2015079239 (Al) document, being a flanged hollow body container set in packets with a circumferential surface that is open at the top of the body or the portable food transport module containers known from US4474303 (A) document.

Typical commercially available plastic packaging for instant products (dry mixes intended for self-preparation of beverages, soups, ice-cream and other foodstuffs) is a cylindrical jar, of circular or oval cross-section and of varying capacity, intended to be closed by means of either a threaded cap or a cork or a push plug.

The cylindrical shape of the packaging and its circular or oval cross-section are due to several premises:

- resistance to external loads (packaging with circular cross-section, due to the stress distribution show the highest resistance);

- simplicity of execution;

- small amount of material used in relation to the packaging volume obtained (in the case of a circular cross-section, the ratio of the cross-section area to its perimeter is the most favourable);

Unfortunately, cylindrical packaging with a circular or oval cross-section also has a number of drawbacks, which are disadvantageous from the point of view of production, customer and logistics, namely:

- cylindrical packaging items placed in a collective packaging fill very poorly the surface on which they are placed (there is a lot of free space between them, as shown in Fig. 1):

- reduction in the diameter of the cylindrical packaging reduces the legibility of the inscriptions on the packaging (label), which, given the ever-increasing amount of information required to be placed on the packaging and the need to maintain a mandatory minimum height of characters, is a factor that cannot be disregarded;

- in the case of cylindrical packaging there is no flat surface, most suitable for marketing and promotional purposes;

- there are difficulties in positioning the packaging in the production line, which is important especially when it is necessary to mark the packaging in the same place, repeatable on all packaging items (cylindrical packaging items rotate on the production lines);

- cylindrical packaging items, when moving on the production line and rotating, rub against each other, which can often lead to damage (abrasion) of the label.

There are known non-cylindrical plastic containers with straight vertical side walls for easy grip in the hand (US5261544 A), equipped with a handle (US2003206998 Al) or having a flat surface on the side walls (US2006175284 Al). On the other hand, from AU2012251953 (Al) document a plastic container is known with an essentially polygonal body structure with flat panels of essentially polygonal structure which move together during and after the sterilization process, while preserving the aesthetics of the plastic container.

The purpose of the invention is to develop such a design of a jar for food packaging, in particular for dry instant products, which will make it possible to combine the advantages of known non-cylindrical containers with the elimination of the drawbacks of cylindrical packaging, while maintaining the stiffness typical of circular cross-section packaging.

This purpose was achieved by means of a non-cylindrical container for packing food products, in particular dry products, according to the invention, comprising a bottom, a body and a threaded flange for the jar to be closed by means of a cap, which is characterised in that it features a high resistance to internal pressure. At least four vertical side walls of the said container are concave inwards and the corners of the said walls are rounded. The top of the non-cylindrical body of the container has a form of a flange with a circular cross-section, which constitutes a three-step clamping ring above which there is a thread outline for closing the container with a screw cap.

Preferably, high resistance of the container to internal pressure is achieved by connecting rounded corners, vertical walls of the packaging that are concave inwards and by the execution of the upper flange.

Preferably, while maintaining the stiffness typical of circular cross-section packaging, the container according to the invention has a flat surface on each wall of the packaging, which is much more advantageous for the advertising message on the label.

Preferably, the resulting flat surface on each wall of the packaging according to the invention has the same "S" dimension. Preferably, movement of the container according to the invention on the production line conveyors is stabilized by side guides.

The object of the invention is presented in the embodiments and in a drawing where fig. 1 illustrates known cylindrical packaging items arranged in collective packaging, fig. 2. presents a model of a plastic jar (container) according to this invention in a side view, in a top view and in a perspective view, fig. 3. presents an advantageous filling of the surface of the collective packaging with a non-cylindrical container according to the invention as compared to cylindrical containers known from the prior art, fig. 4. presents a top view of the container according to the invention with an indication of the rounded corners of the cross-section of the packaging, fig. 5. presents a side view of the container according to the invention with an indication of the vertical walls of the packaging that are concave inwards, fig. 6. presents a model of a plastic jar (container) according to this invention in a side view, in a top view and in a perspective view, with an indication of the execution of the upper flange of the packaging, fig. 7. presents the flat surface of the "S" dimension on each wall of the packaging according to the invention, fig. 8. presents the movement of non-cylindrical packaging according to the invention on production line conveyors as compared to cylindrical packaging known from the prior art, fig. 9. presents a view of a jar with a cap.

Example 1

The invention according to the first embodiment is shown in the drawing (Fig. 2), which presents a model of a non-cylindrical plastic jar (container) in a side view, a top view and in a perspective view, where the said container has vertical sides of the packaging that are concave inwards in concave area 2 located in any place between bottom zone 1 and three-step clamping ring 3.

Example 2

An invention according to the first embodiment, in which the high resistance of cylindrical packaging to internal pressure resulting from the circular cross-section of the jar was achieved in the new packaging through a combination of:

- rounded corners of the cross-section of the packaging (indicated by arrows in Fig. 4.)

- vertical walls of the packaging that are concave inwards - concave area 2 (indicated by arrows in Fig. 5.)

- and by the execution of the upper flange of the packaging with a circular cross-section, the flange acting as three-step clamping ring 3 (indicated by arrows on Fig. 6.).

Example 3

An invention according to the first or second embodiment, in which, while maintaining the stiffness typical of circular cross-section packaging, a flat surface was achieved on each wall of the packaging, which was much more advantageous for the advertising message on the label. The said flat surfaces are marked with the "S" dimension on Fig. 7.

Example 4

An invention according to any of the previous embodiments in which the packaging when moving on the production line conveyors is stable and does not rotate or swing because its movement can be stabilized by the side guides, as opposed to cylindrical and oval packaging (as shown in Fig. 8). This makes it possible to precisely and legibly affix the required information prints on the label in the same place (batch number, date of production, expiry date of the product).

The jar can be used to store bulk products. It can also be used to store other products such as jam, jelly, honey.