DE19540152A1 - Plastic slip lid with a thin mirror area - Google Patents

Abstract

Proposed is a plastic hooded lid (1) used for sealing a container and comprising a lid central portion (7) and a contoured (3, 4) edge region (2) for positive and/or non-positive engagement with the matching container edge. The edge region (2) has a wall thickness sufficient to ensure that the lid is held firmly on the container. The lid central portion (7) is made from a different material and/or a material of considerably less thickness (d2) and rigidity. This ensure that considerably less material can be used during manufacture without compromising the required regidity of the edge region.

Description

The invention relates to a slip lid, in particular from Plastic, as is known for closing a container. For this purpose, reference is made, for example, to DE 35 45 730 A1.

Such slip covers are made from a film by forming and Punched out. The thickness of the film will depend of the material from which the film is made, so determines that after reshaping the edge area and Punch out the slip lid of the edge area an adequate Stiffness and strength is maintained, which after application on a container a sufficiently firm and tight (but detachable) fit even when the container is under stress guaranteed. This means that the cost of materials for the Manufacture of the slip lid by the requirements of the Stiffness and the strength of the edge area is determined. Due to the required thickness, the material expenditure is especially with slip covers of larger diameter, quite considerably. It should be noted that in the marginal area a reduction in thickness occurs due to the reshaping of the film, what from the start when choosing the thickness of the film must be taken into account. Has in the lid mirror area on the other hand, the slip lid is the original thickness of the film which it is made of.

It is an object of the invention in the manufacture of Slip covers to enable substantial material savings, without the strength requirements in the edge area of the Slip covers are neglected.

This object is solved with claim 1 or 4 or 14. Here the edge area retains that for rigidity and strength sufficient thickness, while the lid mirror from a in contrast to other material, but preferably from one Material part of less thickness compared to the edge area consists. This implements the idea that the rigidity and Strength of the lid mirror to lower requirements  suffices as the edge area. At the same time, the considerable material savings in one material Recycling circulation implemented in new films (claim 10, claim 12).

The invention can be applied to slip covers made of metal will. However, it is primarily based on the application of Slip covers made of plastic, so an essential Contribute to reducing the weight of plastic waste Afford.

The cover mirror and the edge region are preferably separated and made of foils of different thicknesses, the both parts are firmly and tightly connected (Claim 2). To do this, on the inside of the border area Leave the flat flange and the separate cover mirror somewhat dimensioned larger so that it overlaps this edge area, whereby both parts tight and tight in the area of overlap are interconnected (claim 3, claim 7, claim 5, Claim 13).

A decisive criterion with which the invention Plastic lid, preferably used for butter or Margarine containers that can be distinguished from those which the prior art shows is the identification by the Thickness difference between the center area of the blank and the Edge area, which the invention calls "slip lid ring" (Claim 5, Claim 14). The smallest thickness of the According to the invention, slip lid ring is still larger than the inner area of the slip lid, which none Deep-drawing deformation process is subjected. The state of the art shows only those plastic lids where the mirror area has a greater thickness than the lack of deformation Edge area, which is opposed in its thickness by deep drawing the starting film material is reduced.  

A slip lid ring (claim 4) is the product of the process inventive method (claim 7). This Slip lid ring has a central opening and one U-shaped ring area (claim 4). He can can be manufactured independently, it can be stored independently and be delivered separately. The insertion of a thinner or lighter inner disc in the inside open slip ring can be done directly at the bottler, he can be like that individual motif or one according to the season or Insert the mirror piece stored in the filling goods and the slip lid thus manufacture completely. With this method of production also the print quality or the quality of the image on the Mirror compared to the prior art improved because of The mirror does not reflect the temperature-related forming process is subject and therefore not influencing one already printed round blank can arise.

The seam connection of the slightly larger and lighter ones retrofitted inner disc can be by welding or Gluing take place (claim 9, claim 13). Punching out the inner blank can simultaneously with the forming of the Slip lid edge take place, the simultaneity relates to a workflow, not a current one Simultaneity (claim 11).

The inwardly protruding flange of the slip lid ring, on which the lighter round blank is attached (claim 9), can be about even run. It can be roughly at the level of the lower open end area of the U-shaped ring area of the slip lid ring and advantageously has a radial width that a sufficient width of the fastening seam allowed (claim 5). If the outer leg of the U-shaped edge area is light the slip lid ring can do better stacked, it can also be lighter and more targeted a container can be placed (claim 6).  

The further use of the punched-out round part according to Claim 7 takes place according to claim 12, according to which this blank is granulated and the manufacturing process of the film again is supplied (claim 10). That prepares in the practical Application no problems because identity of Plastic materials is ensured; the recycled Inner part of the blank fits exactly to the material from which the film is made will be produced. Soiling and interference can almost be excluded.  

The invention (s) are illustrated below using exemplary embodiments explained in more detail.

Fig. 1 is a perspective view of a Stülpdeckelringes 2 einzusetzender inner Ronde. 7

FIG. 2 shows a cross section through the lid edge 2 according to FIG. 1.

Fig. 3a shows a hooded tray according to the prior art.

Fig. 3b shows a slip lid 1 in plan view from the outside (top), according to an example of the invention.

The slip lid 1 has an annular edge area 2 , which is made of a plastic film 20 of a predetermined thickness d₀ by forming and punching. On its radially inner side, the edge area 2 has a flat flange 5 , on the outside of which the downwardly open U-shaped engagement area 3 , with its 3 walls 3 b, 3 c, 3 d, each running approximately at right angles to one another followed, the d in the region of its outer leg 3 and optionally has on its inner side 3 a in a predetermined manner distributed latching nubs 4, to ensure a firm and tight fit of the slip lid after application (snapping) of the slip lid onto the correspondingly shaped edge of a container , as well as easy opening and closing. The engagement area has an obliquely outwardly projecting edge 10 , on which a grip tab 8 can be formed at one point.

The slip lid has a separately produced mirror section 7 with a plastic film thickness d₂ of thinner than the thickness of the film of the edge region, in particular a much smaller thickness. The mirror disk 7 can also consist of a different plastic material. Their weight should be less than that of the punched-out inner disc 7 a, which they replace.

As is apparent from the figures, the mirror blank 7 slightly larger than the clear aperture 7 b of the edge flange 5, so that the edges 6 and 9 a by a predetermined amount overlap (see. Fig. 3b). In this overlap area, the two parts are firmly and tightly connected to one another by welding, gluing, ultrasound or heat sealing, which can be seen from the annular seam 9 .

During manufacture, a cover mirror disk 7 a is punched out from a slip lid of, for example, a conventional type (cf. FIG. 3a) and from a material with a thickness d₀ sufficient for the required rigidity of the edge area. It is replaced by a new blank 7 , which is made separately from a thinner foil material d₂. This film material can also consist of a different plastic than the edge area. The film from which the mirror disc 7 is made has a much smaller thickness than the film from which the edge region (the "slip lid ring" 2 ) is made. The mirror disk 7 and the edge area 5 of the slip lid ring 2 are then connected tightly and permanently to one another at the seam 9 .

The slip lid ring is clear from FIG. 2. It consists of a U-area 3 with two approximately vertical walls 3 b, 3 d and a horizontal connecting section 3 c, which are annular. On the inner wall 3 b, a circumferential reinforcing shoulder 3 a is provided. The outer wall 3 d is bent over a frustoconical strip 3 e to the lower edge 10 in order to obtain a wider opening area. A ring support 5 with an inner edge 6 runs inside.

In an exemplary manufacturing method, a plastic granulate is assumed which softens by the action of heat and is processed into a film 20 of a predetermined thickness d.. The film 20 can also be obtained ready. In the still warm film, slip covers of the desired shape and size are produced by reshaping (e.g. deep drawing) (see FIG. 3a). Then the slip covers are punched out of the film and the cover mirror for each slip cover in the form of a circular blank 7 a. Slip-on cover rings 2 are formed which are stackable and can be traded independently.

The punched-out lid mirror 7 a is processed into granules and fed back into the film production process.

A new circular blank 7 is punched out of a thinner foil material, preferably with a somewhat larger diameter. This foil blank is permanently connected to the inner edge 5 of the previously produced slip lid edge. To connect the parts, the overlap areas can be heated and compressed accordingly by induction or by ultrasound.

It can be seen that instead of a plastic material, another material, in particular also based on paper, which can be appropriately lacquered or coated, can be used for the cover mirror disc 7 .

Claims (14)

1. slip lid, in particular made of plastic for closing a container, which cover ( 1 ) has a cover mirror ( 7 ) and one for positive and / or non-positive engagement with a container edge correspondingly profiled ( 3 ; 3 a, 3 b, 3 c, 3 d; 4 ) edge area ( 2 ), said edge area ( 2 ) having a wall thickness (d₁), which provides sufficient rigidity for a holding effect on the container, while the lid mirror ( 7 ) made of a different material and / or from one material of in particular much smaller thickness (d₂) and rigidity compared to the material of the edge area ( 2 ). 2. Slip cover according to claim 1, characterized in that the cover mirror ( 7 ) and the edge region ( 2 ) are separately manufactured parts which are firmly and tightly connected to each other to form a slip cover from slip cover ring ( 2 ) and mirror zone ( 7 ) (9) are. 3. slip lid according to claim 1 or 2, characterized in that the edge region ( 2 ) radially inside has a flat ring region ( 5 ) with which a cover mirror disc ( 7 ) with limited overlap tightly connected (9), in particular glued, sealed or inductively is welded. 4. slip lid ring ( 2 ) for a slip lid according to one of the claims mentioned, in which

• a) an inner flat area ( 7 b) within an inner peripheral edge ( 6 ) is open;
• b) an outer ring region ( 3 ; 3 a, 3 b, 3 c, 3 d; 4 , 10 ) which is open in a U-shape and is provided and which is in an annular support ( 5 ) leading inwards to the peripheral edge ( 6 ) flows.

5. slip lid ring according to claim 4, wherein the ring support ( 5 )

• a) is arranged approximately at the level of the lower open end region of the U-shaped ring region ( 3 ); and or
• b) the radial width (b) is in the order of magnitude of the opening width of the U-shaped ring region ( 3 ; 10 ).

6. slip lid ring according to claim 4 or claim 5, wherein the outer flank ( 3 d) of the U-ring region ( 3 ) extends outwards ( 3 e, 10 ). 7. A method for producing a plastic slip lid according to claim 1, in which a lid mirror blank ( 7 a) is punched out from a slip lid ( 1 ) from a material with sufficient thickness for the required rigidity of the edge region and by a circular blank ( 7 ) from another and / or a significantly thinner (d₂) material is replaced, the latter ( 7 ) with the remaining edge area ( 5 ) of the slip lid is tightly and permanently connected (9). 8. The method according to claim 7, wherein the other blank ( 7 ) is larger than the punched blank ( 7 a). 9. The method according to claim 7 or claim 8, wherein the connection ( 9 ) is carried out by inductive welding or ultrasonic welding. 10. The method according to any one of claims 7 to 9, in which the punched blank ( 7 a) is returned to the manufacturing process of the starting blank or film ( 20 ) with starting thickness (d₀) for deep drawing the slip lid. 11. The method according to any one of claims 7 to 10, wherein the Stamping process essentially at the same time as the deep-drawing process of the border area.   12. A method for producing a slip lid according to one of claims 1 to 3, in which

• a) a plastic granulate softened by the action of heat and processed into a film ( 20 ) of a predetermined thickness (d₀);
• b) corresponding annular areas ( 3 , 4 ) are formed from the still warm film ( 20 ) by a forming process, such as deep drawing, in the edge areas ( 2 ) of the slip lid;
• c) a blank ( 7 a) is punched out of the film ( 20 ) of the slip lid ( 1 ) and from the mirror area thereof, the blank, which has been punched out, processed as granules and fed back into the manufacturing process according to (a).

13. The method according to claim 12, in which a circular blank ( 7 ) made of substantially thinner (d₂) film material - preferably with a somewhat larger diameter - is connected to the inner edge ( 5 ) of the slip lid ring ( 2 ) remaining by punching out by gluing, welding or heat sealing ( 9 ) will. 14. slip lid ( 1 ) made of plastic, producible according to one of claims 7 to 13, with a mirror ( 7 ) and an edge region ( 2 ), in which the thickness (d₂) of the mirror region is less than the smallest thickness (d₁) of Edge area is.