The invention relates to a receptacle with a container having at least one opening and a lid for closing the opening, which lid is connected to the container by an elastically deformable hinge.
Such containers made of plastic are often used to package liquid products or similar pourable goods. They are made of plastic, with the recloseable lid of the container usually being molded onto a screwed-on lid holder via a film hinge. The lid holder is screwed or snap-fit to the container. EP 2 050 685 A1 describes a receptacle, namely a child-resistant vial, comprising a hollow cylindrical container having a circumferential wall and an opening at one end, wherein as a first connection element a ring is arranged on the circumferential wall of the hollow cylindrical container, which is connected to a lid via a film hinge. The connection element, film hinge and lid are made of polymer material.
It is well known that plastic packaging containers give cause for concern because plastic is impossible or very difficult to biodegrade and pollutes the environment and the oceans.
Harmless packaging made of molded fiber is also known. In English, these containers are called pulp mold containers and are formed from pulp in a suction mold. Water is sucked out of the pulp via the suction mold, whereby pulp fibers present in the pulp are deposited on the wall of the suction mold. The container formed in this way is dewatered and can be used for packaging liquids and bulk materials. EP 1 221 413 A1 describes the manufacture of such a molded fiber container. However, no recloseable lid hinged to the container is disclosed here.
Of course, molded fiber containers with a hinged lid are also known (compare DE 16 11 944 B1). However, egg cartons are described here, which are not liquid-tight and therefore cannot hold liquids or fine-grained powders. GB 2 420 265 A describes a one-piece biodegradable drinking container with a cup section and an integral lid, which is connected to the cup section via a film hinge made of biodegradable material.
The object of the invention is to provide a biodegradable container that is easy to handle and safely stores liquids and pourable materials received therein.
According to the invention, this task is solved in that the container is made of fiber material and has a biodegradable or bioinert coating, that the lid is made of biodegradable thermoplastic material, and that a flexible hinge strip of fiber material attached to the lid is bonded to the container.
Thus, a molded fiber container is proposed that has a biodegradable or bioinert coating so that the container cannot pollute the environment. Biodegradable coatings are usually natural coatings such as lipids, oils or waxes. Bioinert are, for example, coatings containing silicon dioxide. It is further proposed that the lid be made of biodegradable thermoplastic material. Thermoplastic material is particularly suitable for making a container cover. It can be easily and safely processed in large quantities by injection molding. The technology is ideally suited for mass production.
Such a biodegradable thermoplastic may in particular comprise starch and, as further constituents, glycerol and sorbitol as plasticizers. In particular, 11-15 wt % glycerol and 6-9 wt % sorbitol in relation to the total weight of the material in the dried state have proven to be advantageous. In this case, the concentration of starch is between 56 and 63 wt %. Other constituents may be fillers in concentrations of 16-24 wt %. The fillers may be talc, chalk, bentonite, mustard seed husks, organic fibers or waste materials. This material can be excellently processed in twin-screw extruders and injection molded. It can be made moisture resistant and with considerable hardness by applying appropriate coatings. However, this material is usually too brittle to be used as a flexible film hinge to connect the recloseable lid to the container. For this reason, the lid is attached with a flexible hinge strip made of fiber material and bonded to the container.
Such a hinge strip may be made of paper, especially kraft paper. The hinge strip has considerable strength. Appropriate coatings may be used to make the hinge strip moisture-resistant. The hinge strip may be decoratively printed. Consequently, the hinge strip combines the technically required features of flexibility, so that the lid can be opened and closed multiple times, with positive aesthetic features. The fiber material of the hinge strip is biodegradable, even when coated to be moisture-resistant. Consequently, the recloseable packaging with the lid attached by a hinge is harmless to the environment and meets the highest functional and aesthetic requirements.
In practice, the container may have a connection element made of biodegradable thermoplastic material in the area of its opening, the hinge strip being bonded to the container in the area of the connection element. A thermoplastic connection element may be provided at the opening of the molded fiber container to stabilize the opening. Said connection element may be bonded to the molded fiber material of the container or otherwise connected by substance bonding or form-fitting. The lid may be bonded to this connection element by means of the hinge strip, wherein a circular projection of the lid can fit into an annular opening of the connection element. Preferably, cooperating projections and recesses are arranged on the connection element and on the lid, which allow a snap connection or snap-in connection of the lid and the connection element. In this way, the ratio can be securely closed, with the lid being retained on the connection element via the hinge strip in the open state as well.
In practice, the hinge strip may be bonded to the lid. However, it is also possible for the hinge strip to be connected to the lid in some other way. In particular, the lid may be rotatably attached to the hinge strip. This is particularly useful in cases where the lid can be screwed to the connection element.
In practice, the hinge strip may have at least a second section bonded to the container, the second section forming a seal section and being perforated so that it is separated along the perforation when the lid is opened. This seal section serves as a tamper-evident seal. The unseparated perforation allows a purchaser to see that the product within the container is in its original packaging. An opened container can be easily distinguished from an unopened container by the destruction of the perforation.
As mentioned further above, the container may have an external thread in the area of the opening and the lid may have an internal thread that may be screwed onto the external thread. In this case, the hinge strip is rotatably connected to the lid. To achieve a rotatable connection, the hinge strip may have an eyelet formed thereon through which a section of the lid having a circular cross-section extends. For example, a T-shaped pin may be formed on top of the lid and surrounded by the eyelet. Either the hinge strip has some elasticity such that it can be pulled over the periphery of the T-shaped pin and elastically contract. Or alternatively, the T-shaped pin is first inserted through the eyelet and then connected to the lid by form-fitting or substance bonding.
To increase the tightness of the container, the coating may contain at least one of the following constituents:
Cellulose fibers, especially very short microfibrils, are suitable for increasing the tightness and gas impermeability of the container. Fillers and swelling natural constituents such as casein whey, agar agar and psyllium husks also increase the tightness. Silicon oxide gives the container considerable strength.
Lipids such as oils and waxes also increase the gas and liquid resistance of the container material. All the selected constituents are biodegradable or bioinert, so that the container according to the invention decomposes after a short time without leaving any harmful residues.
As mentioned, the thermoplastic material of the lid is also biodegradable, in particular water-soluble and/or compostable. Such properties may be achieved with the starch-based thermoplastics described above.
The connection element may be connected to the container by substance bonding or also by form-fitting. The thermoplastic material may develop adhesive properties by wetting with water or a solvent and be bonded to the fiber material of the container. It is also possible for the connection element to have a thin connecting wall that is provided with holes. The connecting wall is kept close to the wall of the suction mold during the manufacturing process for the molded fiber container, so that fiber material sucked in by the suction mold also settles in the area of the connecting wall and projects through the apertures. This way, an excellent intimate bond between the connection element and the fiber material of the container may be achieved. The connecting wall may surround the opening so that the form-fitting connection is achieved along the entire circumference of the opening.
The invention further relates to a method of manufacturing a receptacle comprising a container having at least one opening and a lid for closing the opening, the lid being connected to the container by an elastically deformable hinge. The method comprises the following method steps:
This way, the various components of the receptacle can be manufactured and joined together efficiently and cost-effectively.
In practice, the connection element made of biodegradable thermoplastic material may be arranged on the container in the area of the opening, with the hinge strip being bonded to the container in the area of the connection element.
The lid and the connection element made of thermoplastic material may form a snap connection or snap-in connection with which the receptacle can be closed. In the open state, the lid is connected to the connection element via the hinge strip.
As mentioned further above, the hinge strip may be bonded to the lid.
Further, the hinge strip may include at least a second section bonded to the container, namely a seal section, which is perforated and separated along the perforation when the lid is opened. In this manner, the hinge strip forms a tamper-evident seal.
Finally, the container may have an external thread in the region of the opening and the lid may have an internal thread that can be screwed onto the external thread, the lid being rotatably connected to the hinge strip.
Further practical embodiments and advantages of the invention are described below in connection with the drawings.
In common plastic containers, such injection-molded parts as the connection element 4 and the lid 5 are pivotably connected to each other by means of a film hinge, which is made of the same thermoplastic. However, the biodegradable starch-based thermoplastic usually has too little elasticity to reliably form a film hinge between lid 5 and connection element 4. For this reason, a flexible hinge strip 6 made of paper, in particular kraft paper, is provided which pivotally connects the lid 5 to the container 1 and in particular to the connection element 4 of the container 1. The hinge strip 6 has a main section 7 extending parallel to the upper side of the lid 5 in
In
Alternatively, a glue or other suitable biodegradable adhesive may be used to bond the hinge strip 6 to the lid 5 and the connection element 4.
The hinged connection between the lid 5 and the connection element 4 is essentially provided by the strip-shaped lateral section 8 of the hinge strip 6. If the main section 7 of the hinge strip 6 covers the entire surface of the lid 5, the hinge strip 6 can be printed and reproduce the product information. However, it is also possible that the main section 7 of the hinge strip 6 does not extend over the entire upper side of the lid 5.
If the lid has a screw thread (not shown) which can be screwed to the connection element, bonding between the hinge strip 6″ and the lid 5 can be dispensed with. In this case, the projecting circular section 11 of the lid 5 can have a groove or slot on its circumference into which the ring-shaped or eyelet-shaped main section of the hinge strip fits. The lid 5 is thus rotatably connected to the hinge strips 6″.
The features of the invention disclosed in the present description, in the drawings as well as in the claims may be essential, both individually and in any combination, for the realization of the invention in its various embodiments. The invention is not limited to the embodiments described. It may be varied within the scope of the claims and with due regard to the knowledge of the relevant person skilled in the art.
Number | Date | Country | Kind |
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10 2022 104 645.1 | Feb 2022 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2023/054003 | 2/17/2023 | WO |