WO2000066450A1

WO2000066450A1 - Screw cap with sealing disk

Info

Publication number: WO2000066450A1
Application number: PCT/EP2000/003985
Authority: WO
Inventors: Horst Trombach
Original assignee: Alfelder Kunststoffwerke Herm. Meyer Gmbh
Priority date: 1999-05-04
Filing date: 2000-05-04
Publication date: 2000-11-09
Also published as: EA003103B1; EP1181211A1; BR0010252A; EE200100570A; CA2377839A1; CZ20013864A3; AU765405B2; JP2002543007A; HUP0200952A2; IL146122A0; NZ514931A; DE19920572C2; PL350613A1; SK15812001A3; ATE249372T1; YU75901A; AU4561100A; DE19920572A1; ZA200109067B; DE50003652D1

Abstract

The invention relates to a cap (40) with sealing disk which can be positioned on, and notably screwed onto, the opening of a container (10). The sealing disk consists of several layers. The upper layers (24) are designed to remain in the cap when the container is opened while the lower layers (21, 22, 23) are sealed to the opening of the container. The upper layers can be used to reclose the container and are not glued in the screw cap. When the container is opened for the first time the upper layers are lifted vertically upwards by the lower layers, which prevents damage to the top side of said lower layers.

Description

Screw cap with sealing washer

The invention relates to a cap with a sealing washer for a container closure for use in a container with an opening delimited by a circumferential edge, the sealing washer consisting of several layers, of which the lowermost layers seal the opening of the container tightly before being opened for the first time and releasably with are connected to the uppermost layers of the sealing washer, wherein these uppermost layers can form a new temporary closure of the opening of the container.

When closing a container, it is often desirable or also necessary to provide the container mouth with a disk-shaped seal which tightly seals the contents, for example liquids or substances such as food.

There are several reasons why this tight closure is required. On the one hand, the content should be protected against external influences, for example against water vapor or oxygen, and on the other hand it should also remain aroma-tight. Another reason lies in aggressive filling goods, for which the best possible leakage protection must be provided. Finally, such a tight seal can also protect the originality for the trade, since a user can immediately recognize whether someone has already manipulated the container contents beforehand.

In addition, the container closure is then closed with a screw cap or a similar element, which ensures the mechanical and stable closure outside the film. When used for the first time, the user destroys the film in order to access the contents of the container and then closes the container (if he has not yet removed all of the contents) with the screw cap, which can temporarily seal the opened contents for a correspondingly short period of time.

CONFIRMATION COPY If the tightness requirements are only low, a cardboard disk can be placed on the mouth of the container as a sealing element, as suggested in DE 94 10 934 U1, or possibly clamped in the screw cap. The sealing disc can then be ejected through a small closure flap in the screw cap in order to allow the contents to flow out of this closure flap again after being screwed on again. After the first opening, however, any seal is lost and the application options are also limited to undemanding and insensitive products.

The film that closes the container content is often like u. a. in EP 0 717 710 B1 and DE 39 20 324 A1 applied by means of induction sealing. To do this, a complete sealing washer is placed, the bottom layer of which forms the sealing layer. Above this is a second layer, usually made of aluminum, which is used to generate and transfer heat during the induction process and, if necessary, provides additional mechanical protection. The second layer is fixed to the first and is particularly advantageous for heat transfer. Above this aluminum layer, further components of the sealing washer are then provided which remain in the cap when the screw or other twist lock is opened.

These additional or upper components of the sealing washer are glued into the screw cap. If this screw cap is turned when it is opened for the first time, the torque is automatically transferred to these upper parts of the sealing washer. These upper parts of the sealing disc thus rotate relative to the opening of the container. The lower parts of the sealing washer, however, are firmly sealed onto the container mouth and do not rotate. In this way, the upper part of the sealing washer is sheared off from the lower part exactly in the separation area provided. The upper part remains in the screw cap, the lower part remains on the container and can now be properly tackled and destroyed by the user.

At this point, however, there are problems. There are certain areas in this area so that the user can peel off this lower part with the sealing layer sensitive measures have been taken. For example, according to EP 0 395 660 B1 or EP 0 534 949 B1, it is provided that the top layer is designed to be foldable by partially not being glued to the induction layer. As a result, it is precisely this non-bonded area that is of course very sensitive to the effects of force, especially in the direction of rotation, where the lack of bonding means that there is no resistance to it. It can therefore happen that destruction or damage occurs here, which in particular gives the unskilled user the impression that the container closure was defective or possibly not tight or was not properly closed. In extreme cases, this process can actually lead to the partial destruction of the sealing layer.

In contrast, the object of the invention is to propose a cap with a sealing washer, in which a more gentle separation of the sealing washer components takes place.

This object is achieved in that the cap has devices for limiting the distance of the uppermost layers of the sealing washer from the underside of the cap in the event of an opening of the cap, and the uppermost layers of the sealing washer can be rotated without tack to the underside of the cap and with respect to it.

With such a concept, the problem is surprisingly solved in a complete departure from the prior art. So far, it had always been assumed that of course the rotary movement of the cap had to be used to separate the two components of the sealing disk of interest from one another. But now the sealing washer is deliberately no longer glued into the cap, but lies loosely in it. This means that when the cap is rotated, the gluing of the upper parts of the sealing washer to the lower parts of the sealing washer means that the entire sealing washer stops and the rotational movement of the cap does not take part. But this in turn means that there is no destruction whatsoever due to the relative rotational movements of the different layers can. The tabs, folds or other skillful preparations on the top layer of the lower layers of the sealing washer remain completely unaffected.

The uppermost part of the sealing washer, which later forms the reseal part, is only lifted vertically upwards. In this case, the vertical upward is parallel or exactly in the axial direction of the opening of the container. This lifting takes place in that, on the one hand, the resilient pressure originally exerted by the cap is eliminated and, on the other hand, by means of appropriate mechanical measures, a slight force is exerted exactly vertically upwards by the cap, which does not only move in a rotating manner upwards.

For this movement, however, a controlled, light connection can be easily adjusted by, for example, a polymer separating layer between the reseal part and the lower layers of the sealing washer. It can be provided in such a way that, although it is stronger than any rotational motion forces and torques that are nevertheless transmitted, it then yields to this vertical influence of force. This vertical lifting of the upper from the lower layers leaves the top of the lower layers unaffected. They are not shifted or kinked relative to each other or to each other, but remain unaffected.

The user can now carry out the respective manipulations, for example lifting partially glued areas, erecting folds vertically and the like. Then he can completely remove this lower area from the container. As in the prior art, the screw cap now has a reseal part which is ideally suited for reclosing the container. Now it doesn't matter whether and how this reseal part moves, it is simply screwed back on with the screw cap. Despite the lack of gluing, it does not fall out of the screw cap, since it is held in the cap by the mechanical interventions, in particular grooves and beads. It is particularly preferred if the sealing washer has a constant outer diameter across all layers. This means that a single punching device can be used and only one punching process is required. In the prior art it was sometimes preferred because of the sensitivity of the upper layers to arrange outwardly projecting tabs on individual layers, as in EP 0 697 345 A2, in order to counteract this.

An exemplary embodiment of the invention is explained in more detail below with reference to the drawing.

It shows:

Figure 1 is a schematic, not to scale, cross section through a screw cap with a sealing washer during opening.

FIG. 1 shows the area of the opening 11 of a container 10. It can be a bottle, a container for agrochemicals, a container that can be sealed to prevent aroma, for example for powdered coffee or the like. The opening is surrounded by a peripheral edge 12. The rim 12 is generally circular.

After filling the container and before opening for the first time, there is a sealing washer 20 consisting of several layers, which is closed at the top and at the side by a screw cap base body 40.

Viewed from the container, the pane 20 initially begins with a sealing layer 21. An induction layer 22, usually made of aluminum, follows this sealing layer 21. This induction layer ensures that heat generated by induction in the layer 22 is transferred to the sealing layer 21 and this is firmly sealed onto the edge 12 of the opening 11 of the container 10 during the production or packaging process.

A layer 23 follows next to the induction layer 22. By means of this layer 23 the user is able to remove the sealing layer 21 together with the induction layer 22 if he wants to get to the contents of the container 10. For this purpose, this layer 23 has, for example, tabs projecting outwards or else a corresponding fold in itself Seize on. In the illustration in FIG. 1, this is indicated by such a projecting fold. In the completely closed state, this fold lies naturally flat and takes up practically no additional space. In practice there is then no space between the layer 23 and the next layer 24 lying thereon, the so-called reseal part. The reseal part 24 therefore lies directly on the layer 23, possibly on the flat fold of the layer 23.

All layers are glued together, the layers 21, 22 and 23 very firmly by means of adhesive layers, since they should not and no longer have to be separated from one another. The layers 23 and 24, on the other hand, are coupled to one another by a relatively easily detachable connection which is in any case easily controllable with regard to their adhesive strength. When choosing the adhesive and separating material between the layer 23 and the layer 24, care should be taken to ensure that any material that remains essentially remains on the layer 23.

The total thickness of the layers 21, 22 and 23 is very small in relation to the other container and opening dimensions. Their presence or absence is virtually irrelevant to the process of screwing or plugging the cap 40 onto the container 10. It should be pointed out again that Figure 1 is in no way to scale here.

On the screw cap 40, on the one hand, a fastening device 43 is provided, for example an internal thread, which engages in corresponding (not shown) counter-fastening elements of the container 10. The cap 40 can therefore be screwed on here.

Noticeable and different from the prior art is not only one between the uppermost cover level of the cap 40 and the fastening device 43

Free space is provided for a sealing washer 20, but this free space also has an inwardly projecting groove 41 or coordinated with it Relationship to this groove 41 to the outside slightly projecting bead 42. The proportions are also slightly exaggerated here.

Unlike in the prior art, no adhesive connection is provided between the sealing disk 20 or the reseal part 24 of the sealing disk 20 on the one hand and the underside of the cover of the cap 40 on the other hand. The sealing disk 20 in its entirety is thus rotatable relative to the cap 40.

The groove 41 is just arranged so that the reseal part 24 fits into the bead 42. When the cap 40 is screwed onto the container 10, this reseal part 42 easily reaches this area by means of slight mechanical tension or suitable thermal measures via the slight resistance of the groove 41. Before the container is opened for the first time, the resal part 24 is not even separated from the lower layers 21, 22 and 23 of the sealing disk 20. These still remain together.

This connection is released only when the container is opened for the first time when the screw cap 40 is unscrewed. In contrast to screw caps from the prior art, this does not happen, for example, in that the torque of the screw cap 40 is transmitted to the reseal part 24 when it is opened, and in this way the connection of the reseal part 24 to the lower layers of the sealing washer is “twisted off”. The reseal part 24 simply stands still and only the then missing compressive force connected from above with the mechanical engagement of the groove 41 on the reseal part 24 leads to the reseal part being lifted vertically without any rotation upwards. The reseal part thus remains in the cap 40, while the lower layers remain on the container 10.

A phase is indicated schematically in the figure, in which the separation between the layers 23 and 24 from one another has just taken place. Both

Layers are not twisted against each other, they move along the

Axis of the container mouth from each other. The indicated fold begins to set up; in practice, however, manual help will usually be required.

After the screw cap 40 has been opened for the first time, the user thus has free access to the layer 23 with the manipulation means specified there, for example the tab or the protruding fold.

If he has now loosened these lower layers and partially removed the contents of the container 10, he can in turn seal the container with the screw cap 40 and the reseal part 24 located therein. The container is then no longer originally sealed, but it can be closed for a temporary period in this way. Of course, the opening can then be repeated in order to gradually consume the container contents.

Reference list

container

Opening the container

Edge of the opening

Sealing washer

Sealing layer

Induction layer

Opening layer

Reseal part

cap

groove

Surround

Fastening device

Claims

Expectations

1. screw cap with sealing washer for a container closure for use in a container (10) with an opening (11) delimited by a peripheral edge (12), wherein

- The sealing disc (20) consists of several layers, of which the lowest layers (21, 22, 23) the opening (11) of the container (10) in front

Close the opening of the container tightly

- The lowermost layers (21, 22, 23) are detachably connected to the uppermost layers (24) of the sealing washer (20)

- these uppermost layers (24) can form a new temporary closure of the opening (11) of the container (10),

- The cap (40) means (41, 42) for limiting the spacing of the uppermost layers (24) of the sealing washer from the underside of the cap

(40) in the event of an opening of the cap (40) and

- The top layers (24) of the sealing washer (20) non-stick to the bottom of the

Cap (40) and are rotatable relative to this.

2. Cap with sealing washer according to claim 1, characterized in that the outer diameter of the sealing washer (20) over all layers (21, 22, 23, 24) is constant and without projections.

3. cap with sealing washer according to claim 1 or 2, characterized in that the means (41, 42) for limiting the distance of the uppermost layers (24) of the sealing washer (20) an inwardly projecting groove (41) and / or one after projecting bead (42) on the outside.

4. Cap with sealing washer according to one of the preceding claims, characterized in that a defined separating layer is provided between the lower layers (21, 22, 23) and the upper layers (24) of the sealing washer (20), which does not rotate relative to one another separation by vertical lifting of the layer groups from each other allows.

5. Cap with sealing washer according to claim 4, characterized in that the separating layer creates a stronger connection than the release force by the torque transmitted via the mechanical contacting of the upper layer (24).

6. Cap with sealing washer according to one of the preceding claims, characterized in that the lower layers (21, 22, 23) have on their upper side a release device which does not protrude beyond the outer circumference of the sealing washer (20), in particular an intermediate fold.