DE2232799B2 - PACKAGING CONTAINER - Google Patents

Description

The invention relates to a packaging container which is made from a web or a flat blank a carrier material coated with thermoplastic by folding and heat sealing the packaging material is made and after filling by welding a transverse to the packaging container directed welding rib is to be closed. Such a packaging container for disposable packaging, in particular for liquids, is known from DT-AS 86 417.

The carrier layer - usually paper or cardboard - of such a web is coated at least on the side that is to form the inside of the packaging container with a homogeneous coating of heat-sealable plastic, such as polyethylene. Packaging blanks are either punched out of the web, or the web is folded into a rectangular tube, which is then welded along its longitudinal edges, then filled with the filling material and finally closed by successive, spaced-apart, transverse welds to form individual packs. ^ft 5

When the packaging container is manufactured from a blank punched out of a web, the latter is first formed into a packaging container by moving along preferably already beforehand attached folding grooves, which facilitate folding, folded and by heat-welding the thermoplastic cover is locked.

However, packaging containers produced in this way are relatively difficult to open because the The layer of the carrier material is difficult to tear and the thermoplastic layer forms a tough inner membrane, which makes it even more difficult to tear open the packaging. To make it easier to open this known packaging it is customary to have marked tear-off points in the packaging walls in the form of Arrange perforations that partially break through the packaging walls. However, it has been shown that these tear points are not as effective as one might wish, and that it is also difficult to arrange these tear points in the packaging material in such a way that an absolute guarantee it is given that the packaging material is not completely punched through.

The object of the invention is to open the roof rib of such a known packaging container make it much easier.

To solve this problem it is proposed according to the invention that the carrier material consists of Polystyrene foam with a coating of one or more homogeneous plastic layers from one or several thermoplastic materials that have an orientation (molecular orientation in a Direction), which coincides with the longitudinal direction of the welding rib.

The nomogenic plastic material can preferably consist of homogeneous polystyrene film, and the sheet of polystyrene foam may also preferably be be extruded.

According to a further embodiment, the invention also relates to a method for producing a Packaging container according to the invention, characterized in that a sheet of polystyrene foam is coated with one or more homogeneous thermoplastic layers by extrusion, wherein the enrobing is carried out at a web speed kept higher than that Speed with which the thermoplastic layer emerges from the extruder, with the result that the Layer (s) made of thermoplastic is (are) stretched during the coating process with orientation of the molecules and that the packaging blank is then punched out of the web and when punching with respect to the The web is oriented in such a way that its parts, which are to form the welding rib of the packaging container, lie in the longitudinal direction of the web.

By arranging the upper closure of the packaging in the manner described, a tight and stable packaging achieved. However, if the packaging is made of cardboard, for example, is it is very difficult to open them even with the use of scissors or a knife as it is necessary is to cut or pinch four layers of cardboard under the welding zone of the welding rib.

If the packaging material instead of cardboard made of foamed plastic, for example from extruded foamed polystyrene, with a coating of one in the longitudinal direction of the web oriented homogeneous plastic layer is made, opening is made much easier because a extruded polystyrene foam film settles in the packaging material without prior weakening

can easily be torn open. This homogeneous, foamed plastic layer can namely in the Direction of orientation can be torn up quite easily, while it is extremely difficult to find it in others To tear open directions. By using a polystyrene foam as the carrier material for the packaging and an oriented, homogeneous plastic film, preferably made of polystyrene, as a coating material of the carrier layer in this way, the packaging material can be oriented in the direction of orientation of the plastic layer can be torn open very easily, while it is difficult to tear in other directions is.

In the drawing, a preferred embodiment of the invention is shown as an example. ι j

F i g. 1 shows a packaging material web on which a series of consecutive packaging blanks is indicated;

F i g. 2a to 2c show the finished packaging and the process of opening the same;

Fig.3 shows a method for producing a Packaging material for packaging according to the invention; and

F i g. 4 shows a section through a packaging material web on a larger scale.

F i g. 1 shows a web 1 of the packaging material on which packaging blanks 2 are arranged one behind the other are. In the figure, the packaging blanks 2 are before their separation from the web, but after Attaching the folding grooves is illustrated to make folding easier. As shown in FIG. 1 are the Packaging blanks arranged transversely to the packaging material web 1, and each packaging blank 2 has four side walls 4 and one (with respect to the packaging) longitudinal connecting section 13, which is to serve as a connecting strip when the packaging blank 2 is folded into a tubular shape of square or rectangular cross-section. Each of the packaging blanks 2 is also with upper sealing fields 5,9,10 and lower sealing flaps 7,8,11 equipped. The hatched areas 6 are unavoidable punching waste of the web.

The upper closure sections of the packaging blank 2 are two rectangular sections 5 and two triangular sections 9, and these sections 5 and 9 are interconnected by triangular fold-in sections 10 tied together. The rectangular fields 5 and the fold-in sections 10 are also connected to the welding bar 3 connected.

When producing the upper end of the packaging, the triangular sections 9 are above the opening of the packaging container folded against each other, the fold-in sections 10 come between the rectangular sections 5 and the triangular sections 9 to lie. The closure sections 3 are placed against one another and form the flattened welding groove 16.

The bottom of the package is formed in a similar manner to the upper end of the package, but with the difference that, since welding of the ground happens to the floor in the forming flaps 7, 8, 12 are not connected to a welding portion ti by that the longer of the rectangular base sections 8 with its outer part overlaps the shorter rectangular tabs 7 and (15 all the sections forming the base are folded together to form a flat base which is pressed together between heated surfaces so that the thermoplastic coating is melted and the holds the bottom-forming sections in the position in which they are nested.

Fig.2 shows a finished package in which the The folded-up closure sections 3 form a welding rib 16. The welding sections 3 are welded to one another along a welding zone 17, which in the case shown here are not extends over the full height of the welding rib.

Since it is desirable in the present case to open the packaging by tearing open the welding rib 16 below the welding zone 17, the packaging blanks are made from a web in the manner shown in FIG. 1 punched out manner or orientation, according to which the carrier layer of the packaging material consists of extruded polystyrene foam and the homogeneous plastic layer consists of a polystyrene film oriented in the longitudinal direction of the web. Since the homogeneous plastic layer in the illustrated embodiment is aligned in the direction of the length of the welding rib 16, the tearing of the welding rib 16 along the area 18 below the welding zone 17 is very simplified, but it is of course possible to further facilitate the tearing, a slight perforation or to provide slots along the tear zone 18.

When the welding rib 16 is torn open along the tear zone 18 (FIG. 2b), the torn parts are of the rib 16 is folded outwards or torn off, whereupon the inwardly folded triangular flap 19 can be pulled out (FIG. 2c) and forms a diamond-shaped opening 20 through which the contents the packaging 14 is made accessible.

3 shows a prefabricated sheet 30 of extruded polystyrene foam from a roll 25 is removed and guided over guide rollers 26, 27 under an extruder. Through the extruder 31, a homogeneous polystyrene film 32 is extruded and onto the sheet 30 of foamed polystyrene placed, whereupon the coated web 30 between cooled press rolls 28, 29 for lamination of the material is introduced.

By now keeping the speed of the web 30 much higher than the speed, with which the polystyrene material is pressed out of the extruder 31, the extruded material is stretched Polystyrene films 32, optionally 5 to 20 times the length. By stretching in association with the Laminating becomes an orientation of the molecules of the extruded polystyrene in that previously described Way achieved, and this has the result that the polystyrene layer is easy in the direction of orientation is tearable, while tearing in other directions is only possible with difficulty.

Finally, FIG. 4 shows a section through a produced web of packaging material on a larger scale Scale. The layer of polystyrene foam is 30 and the extruded and oriented homogeneous Polystyrene layer designated by 32.

It has been found that an excellent packaging material achieves the above-mentioned purpose when a previously extruded sheet of polyityrol foam of a thickness between 0.25 and 1.5 mm with a ^ m homogeneous film of polystyrene is coated or coated, which in this oriented layer has a thickness of 0.02 to 0.2 mm. It has been shown that, instead of polystyrene, other plastic materials can also be used as the coating layer

and it has been found possible to use polyethylene or polypropylene, for example. the However, the best results have been achieved with polystyrene as the coating material.

It is of course also possible to cover the outside of the polystyrene foam with a plastic layer overlay to enhance the appearance of the packaging. The foamed polystyrene material is but not, like paper or cardboard, moisture-absorbing, and a plastic coating on the outside it is therefore not absolutely necessary to protect the packaging against the humidity of the surroundings.

For this purpose 2 sheets of drawings

Claims (3)

Patent claims: t. Packaging container made from a sheet or a flat blank made from a thermoplastic coated carrier material produced by folding and heat sealing the packaging material isx and the after filling by welding a transverse to the packaging container directed welding rib is to be closed, characterized in that the carrier material made of polystyrene foam with a cover of one or more homogeneous plastic layers consists of one or more thermoplastic materials that have an orientation (Molecular orientation in one direction) is imparted with the longitudinal direction of the welding fin matches. 2. Packaging container according to claim 1, characterized in that the web consists of a layer Polystyrene foam and one or more layers of homogeneous, in the longitudinal direction of the web oriented polystyrene. 3. A method for producing a packaging container according to claim 1, characterized in that that a sheet of polystyrene foam by extrusion with one or more homogeneous Thermoplastic layers is coated, the coating being carried out at a web speed which is kept higher than the speed with which the thermoplastic layer emerges from the extruder, which has the consequence that the layer (s) of thermoplastic during coating is (are) stretched with orientation of the molecules and that the packaging blank is then made the web is punched out and, when punched out, is oriented with respect to the web such that its parts, which are to form the welding rib of the packaging container, in the longitudinal direction of the Web lie.