EP2364925A1 - Container with closing membrane - Google Patents

Abstract

The container has an outwardly projecting, annular flange (16) which bounds an opening (18) and is bounded by a receptacle periphery (20), and has a sheet-like closure membrane (22) which is sealed against the flange to form a common, annular connecting surface (28). The closure membrane, starting from a tear-open tab (23), projects freely beyond an outer annular periphery (26) of the connecting surface. The distance between a membrane periphery (21) and outer annular periphery decreases continuously to zero on either side of the tear-open tab in relation to a diameter line.

Description

The invention relates to a container having an opening bounding, outwardly projecting, limited by a cup rim, annular flange and to form a common, annular, bounded by an inner edge of the ring and an outer ring edge connecting surface against the flange geschlegelten, the opening closing and Peelable from the flange, follenförmigen, bounded by a membrane edge closure membrane with a tearing over the edge of the cup tear-open.

It is known to provide containers, such as deep-drawn, injection-molded or otherwise shaped containers, at its opening with a flat, annular flange and such containers, especially after filling, to cover, the lid or the sealing membrane over the entire surface rests on the flange and is peelably and sealingly attached, for example by sealing or gluing the flange. Such containers, trays, meal trays, for example with one or more compartments, cups, small packages, etc., are known, for example, for packaging food of all kinds, e.g. Milled products, in particular yoghurt, whipped cream. Sour milk, sour cream, coffee cream, Ferdgzubereitungen of salads or half or full canned food, pre-cooked or otherwise prepared dishes, drinks, such as fruit and vegetable juices or drinking water.

The lids, sinkers or sealing membranes are exemplarily punched out of an endlessly present, sheet-shaped lid material and stacked. The lid stacks are fed to a packaging machine and the isolated or unstacked, provided with a sieve layer lid are sealed by means of a Slegelwerkzeugss in the flange portion of the container on the container edge of the already filled container. The lids are often embossed or provided with Abstandhaltem when they are processed from magazines. Alternatively, the lidding film of the Roll are processed and stamped together after sealing with the cup.

Usually, the lid material is sealed flush with the cup rim, and the lid is typically mounted on a tear tab. By leashing on the tear-open tab, the lid should peel away from the sealing flange without it breaking in, thereby preventing the container from opening completely. When opening the lid, however, there is a particularly unfavorable trigger angle at which the film is particularly easy to break. Here, the tensile force acts particularly strong on opening the lid on the edge of the lid, so that the lid no longer peels from the cup, but einreisst. Particularly high is the tearing tendency at the beginning of the tearing process, since the lid edge here requires very little force for reloading. As the opening progresses, the risk of tearing decreases more and more.

The Einrelssen of lids or sealing membranes at the opening is a nuisance for the consumer. In addition, the Einrelssen prevents further thinning of the lid material, as this Einrelssen would occur even more because of the lower Einrelsskraft.

A relatively strong seal, e.g. over 8 N / 15 mm, and the typical flush sealing lid cover with the outer edge of the cup wear particularly strong to tearing bel, since the lid foil is torn off virtually from the sealing edge. Here, in contrast to the high tensile strength of the lid material, relatively low tearing or tear resistance of the lid materials acts directly on the edge of the lid.

The tearing of the lid material can be prevented by increasing the material thickness or by laminating with tear-resistant follicles. Both solutions increase the costs considerably.

Out WO 2008/0116444 A1 It is known to prevent the tearing of peelable, sealed on a container edge lids at least in the critical area the lid edge z. B. reinforce by turning over.

Out WO 2008/068326 A1 it is known for cover rings for flaring on cans that the sealed onto the cover ring sealing film to prevent the tearing of the film edge during the peeling process in one embodiment has a over the entire outer edge of the film reaching beyond its attachment area also protruding Rendstrelfen. In another embodiment, the Verschlussfolle on both sides of the grip tab on the attachment area outwardly projecting "ears" on.

The solutions offered in the prior art are associated with an additional cost of materials and thus with higher costs.

The invention has for its object to design in a container of the type mentioned, the connection of the sealing membrane with the container so that bel only slightly higher material use opening without Einrelssen the membrane is possible.

For solving the problem according to the invention, the sealing membrane projects freely beyond the outer ring edge of the veneering surface from the tear-open tab and the distance of the membrane edge from the tear-off tab to the outer ring edge is opposite to a diameter line extending in a tear direction on both sides of the tear-open tab to an angle of at least every 45 ° decreases steadily to zero.

Preferably, the distance of the membrane edge to the outer ring edge of the connection surface decreases steadily to an angle of approximately 90 ° to zero.

With the inventive solution, the possibility of Einrelssens is overcome by a low tear resistance. Through the flowing transition the tear tab the required supernatant of the sealing membrane on the Slegelrand be kept very small and leads only to a low material consumption of about 1%.

The breakage level can also be reduced by reducing the area of connection between the flange and the closure membrane in the region of the pull-tab, e.g. through a narrower design, is reduced. In practice, this can be achieved for example by a corresponding gradation in the flange.

In the sealing of cup materials, high tearing forces may occur depending on the sealing medium and conditions. The Aufrsskraft is very different over the circumference of the cup and is characterized in particular by a sharp increase at the beginning of the opening process and the tearing of the membrane with the container open. This rear increase in tensile force can be neglected, since usually the membrane at the rear end of the circumference is left by the consumer on the container.

The front, very strong Zuganstieg is achieved at the moment where the unsealed edge portion of the tear-open tab of the lid at the so-called collision point on the sealed cup edge. In the case of very strong sealing, when the membrane is flush with the edge of the cup on all sides, it is even frequently observed that the tab is separated from the rest of the lid.

Surprisingly, it has now been found that by avoiding the run-up of the tab edge on the edge of the cup, the above-mentioned Zugspitze can be significantly reduced. This allows the cup to be opened with less force and much more evenly. It can be dispensed with after halves opening to avoid a collision point between the edge of the lid and cup edge, since the rear lid circumference does not tap toward the cup rim, but only by the changed pulling direction of this is peeled off.

In a first embodiment, the common annular interface is concentric with the cup rim and the outer annular edge of the interface is substantially congruent with the cup rim.

In this embodiment, therefore, starting from and on both sides of the tear-open tab, a projection of the closure membrane over the edge of the cup results in the region of a first flange half. If necessary, this projection can be avoided by means of a flange or cup edge which is eccentrically shaped in this area.

In a second embodiment, the common annular interface is arranged eccentrically to the annular flange on the diameter line extending from the tear tab in the tearing direction about a flyback directed away from the tear tab, and the edge of the closure membrane is substantially congruent with the cup rim except for the tear tab.

Instead of an eccentric displacement of the annular connecting surface to the flange, in this embodiment, the flange or the cup rim can be eccentrically shaped.

Depending on the requirements, the lid material can consist of a wide variety of materials. Typical examples are metal foils coated on one or both sides with plastic. Other lid materials contain or consist of plastics in the form of monolayers or multilayer laminates. Further cover materials may be made of cellulose-containing materials, such as line glass or paper. Also used are laminates of metal and plastic films. In order to seal the lid material with the container edge, the lid material is usually voilflächig with a sealing layer, such as a sealing wax, a sealable extrusion layer or a Sealing film provided, wherein the sealing layer on the on the finished packaging inwardly facing side, that is facing away from the container interior, is arranged. In case of non-metallic metal foils which are protected against corrosion over the entire surface, however, ring-shaped or partially applied sealing slaves are also possible.

The containers are usually molded from plastic by deep drawing or injection molding. Suitable containers can also be made by deep drawing of lacquered or extrusion coated films of metal or of metal / plastic laminates.

Fig. 1

einen Schnitt durch einen Behälter mit Flansch und gegen den Flansch gesiegelter Verschlussmembran;

Fig. 2

eine Sicht auf die Rückseite des Flansches des Behälters von Fig. 1 In Blickrichtung Y mit einer auf eine erste Art gegen den Flansch gesiegelten Verschlussmembran;

Fig. 3

eine Sicht auf die Rückseite des Flansches des Behälters von Fig. 1 In Blickrichtung Y mit einer auf eine zweite Art gegen den Flansch gesiegelten Verschlussmembran.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the Zelchnung; this shows schematically in

Fig. 1

a section through a container with flange and against the flange sealed sealing membrane;

Fig. 2

a view of the back of the flange of the container of Fig. 1 In the direction of view Y with a sealed in a first way against the flange closure membrane;

Fig. 3

a view of the back of the flange of the container of Fig. 1 In the direction of view Y with a sealing membrane sealed against the flange in a second way.

An in Fig. 1 illustrated container 10 in the form of a cup made of plastic for receiving, for example, yogurt has a bottom 12 and a towering from this, a product volume limiting side wall 14. From the bottom 12, the side wall 14 extends, in the example shown with an outward inclination angle, upwards and goes at its bottom distal end in a horizontally outwardly projecting, annular flange 16 over. The transition from the rare wall 14 in the annular flange 16 defines a container opening 18. The free end of the flange 16 forms a cup rim 20. Against the annular flange 16 is a the container opening 18 tightly closing and peelable from the flange 16, follenförmige board or sealing membrane 22nd sealed. Slewing is carried out with a sealing tool with an annular or full-area punch and leads to an annular, bounded by an inner ring edge 24 and an outer ring edge 26, common annular connecting surface 28 between the flange 16 and sealing membrane 22, which has a membrane edge 21 limited sealing membrane 22 at one point on the cup rim 20 superior tear strip 23.

At an in Fig. 2 shown, the first connection between the flange 16 and sealing membrane 22, the seal is carried out so that the common annular connection surface 28 between the flange 16 and sealing membrane 22 is arranged concentrically to the flange 16 and the outer annular edge 26 of the annular connection surface 28 is substantially congruent with the cup rim 20 , Starting from Aufrelsslasche 23, the sealing membrane protrudes beyond the outer annular edge 26 of the annular connection surface 28 and thus beyond the cup rim 20, wherein the distance between the edge 21 of the closure membrane 22 and the cup rim 20 on both sides of the tear tab 23 over a first flange half up to an angle of both sides of each 90 ° to a tear direction x defining Durchmesserilnle steadily decreases to zero. About the subsequent second flange half of the membrane edge 21 is congruent with the cup rim 20 and the outer annular edge 26 of the annular connecting surface 28. To ensure peeling of the sealing membrane 22 without risk of tearing, the membrane edge 21 should at least up to a two-sided angle of protrude about 45 ° above the cup rim 20.

At an in Fig. 3 shown, the second type of connection between the flange 16 and sealing membrane 22, the Slegelung done so that the common ringförmlge Connecting surface 28 between the flange 16 and sealing membrane 22 on the Aufrelisslasche 23 extending in the tear direction x diameter line is arranged around a Aufreissiasche 23 directed Verschührungsungsmass a eccentric to the annular flange 16 and the edge 21 of the closure membrane 22 except for the tear tab 23 substantially is congruent with the cup rim 20. On both sides of the pull-tab 23, the closure membrane 22 which is congruent with the cup rim 20 protrudes beyond the outer annular wall 26 of the annular connection surface 28, the distance between the edge 21 of the closure membrane 22 and the outer annular edge 26 of the annular connection surface 28 beldselts the tear-open tab 23 over the first Flange half decreases steadily to zero at an angle of beldselts at 90 ° to the diameter direction defining the tearing direction x. About the subsequent second flange half of the membrane edge 21 extends substantially congruent with the cup rim 20 and the outer annular edge 26 of the annular connecting surface 28. In order to ensure peeling of the sealing membrane 22 without risk of tearing, the membrane edge 21 should also at least in this variant up to a two-sided angle of about 45 ° beyond the outer annular edge 26 of the annular connecting surface 28 protrude.

The closure membranes shown in the drawing have a circular shape corresponding to the cups with a circular opening. However, the invention is not limited to these examples, but also includes other geometric container openings and lid shapes, such. B. oval and polygonal shapes.

Claims (7)

Container with an opening (18) defining, outwardly projecting, of a cup rim (20) limited, annular flange (16) and one to form a common, annular, of an inner annular edge (24) and an outer annular edge (26) limited connection surface (28) sealed against the flange (16), the opening (18) vergelessenden and from the flange (16) peelable, foil-shaped, of a membrane edge (21) limited sealing membrane (22) with a on the cup rim (20) protruding tear tab (23)
characterized in that
the closure membrane (22) protrudes freely beyond the outer ring edge (26) of the connection surface (28) from the tear-open tab (23) and the distance of the membrane edge (21) from the tear-off tab (23) from the tear-off tab (23) is opposite to one another in a tear direction (x) extending diameter line on both sides of the tear tab (23) to an angle of at least 45 ° steadily decreases to zero. A container according to claim 1, characterized in that the distance of the membrane edge (21) to the outer annular edge (26) of the connecting surface (28) steadily decreases to zero at an angle of approximately 90 °. Container according to claim 1 or 2, characterized in that the common annular connecting surface (28) is arranged concentrically to the cup rim (20) and the outer annular edge (26) of the connecting surface (28) is substantially congruent with the cup rim (20). A container according to claim 3, characterized in that the cup rim (20) is eccentrically shaped and substantially congruent with the closure membrane (22). Container according to claim 1 or 2, characterized in that the common annular connecting surface (28) eccentrically on the diameter line extending from the tear-open tab (23) in the tear-open direction (x) about a displacement measure (a) directed away from the tear-open tab (23) Is arranged to the annular flange (16) and the edge (21) of the closure membrane (22) to the tear tab (23) is substantially congruent with the cup rim (20). A container according to claim 5, characterized in that instead of an eccentric displacement of the annular connecting surface (28) of the cup rim (20) is eccentrically shaped. Container according to one of claims 1 to 6, characterized in that the common annular connecting surface (28) is reduced or narrower in order to reduce the tear resistance in the region of the tear-open tab (23).

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