MXPA99003862A - Resealable thermoformed container - Google Patents

Abstract

The present thermoformed containers are recloseable and resealable. This is accomplished primarily by providing a thermoformed container (12) with a threaded neck (14) and the use of a conventional type of closure (26) on the threaded neck of the thermoformed container. The threads (22) are on the neck and preferably also on an outwardly extending peripheral edge (16) on the neck. This outwardly extending peripheral edge is created in thermoform molding. The neck preferably also is in the form of a two or more ply structure and in a further preferred embodiment the neck is reinforced by the closure. The closure in the embodiment of external threads on the neck has a reinforcing plug (30). In this embodiment the reinforcing plug fits into the neck adjacent the inner wall of the neck while the threads of the closure contact the exterior wall of the neck. In the embodiment of internal threads on the neck the closure can have a skirt which is in close contact with the exterior wall of the neck. This will likewise reinforce the neck. The neck can be of many shapes from cylindrical to approaching a rectangular shape.

Description

TJN RECIPIENT TERMOFORMETTE RE3E ABJ-.E Field of the Invention This invention relates to a thermoformed container that can be opened and resealed. More particularly, this invention relates to a thermoformed container having a beak assortment end and a cap that threadably engages and seals the spout or duct end.

Background of the Invention Thermoformed containers are relatively inexpensive to produce. However, these have the disadvantages that they are difficult to fill and can not be closed again with a good seal. The latter is an outstanding disadvantage when the contents of the thermoformed containers are not all to be used all at once. When the product is going to be filled in two or more parts, a container must be resealable. Also, the resealing feature must be a leak-proof seal. This is difficult in view of the fact that thermoformed containers usually have thin walls.

When the walls of the container are thin and flexible it is difficult to obtain a good seal. This is particularly the case where the walls in the seal area and the Reseal feature are thin and lexible.

The prior art in relation to thermoformed containers that can be reclosed is described in U.S. Patent Nos. 3,278,08; 3,913,734; 4,209,096 and 5,228,782. In U.S. Patent No. 3,278,085, it describes a pouch container that is opened by removing a tearing portion to open a nozzle. The nozzle is closed by bending over the upper part of the nozzle with the folded part supported by two closing appendages.

In U.S. Patent No. 3,913,734 the container is of a type of blister package with a backing board having a memory of its original position. The container nozzle is opened by folding back the backing board. When any of the contents have been filled, the backing board regains its original shape by closing the container. This container is improved on the patent of the United States of America number 4,209,906. In this patent, security means were added to establish that the backing board acquires its original position and retains its original position.

The patent of the United States of America number . 228.782 describes another type of bag overdosing that can reuse. The mouthpiece is opened by removing a tear appendix. The pouch is closed and fixed by bending over a nozzle at an angle e. insert the end of the nozzle into a retention groove.

A closure technique uses an aperture interfit projection as described in European patent 18,118A. This can be used to secure an over-bent part to a main part of a container. _ None of these references discloses an effective resealing feature for the thermoformed container. In addition, none of the thermoformed containers have an effective leak-proof resealable feature and clearly do not have a resealable feature that can withstand poor handling.

The thermoformed containers of the present invention solve the problem of providing thermoformed containers with resealable closures wherein the cover or closure provides leak proof seals when reapplied to the thermoformed container. This thermoformed container can be used in cases where a liquid or a solid will be supplied in multiple doses over a period of time.

Brief Summary of the Invention This invention is directed to a resealable thermoformed container that can be reclosed. The thermoformed container is composed of a first longitudinal section and a second longitudinal section. Each of these sections has a peripheral edge extending outwards, the first longitudinal section and the second longitudinal section being joined at the peripheral edge. The first joined longitudinal section and the second longitudinal section are closed at one end and open at the other end.

The open end of the thermoformed container ends in a neck. This neck has a thread on at least a part of the surface. These can be internal or external threads. Preferably there are also threads on the edges that extend outward in the neck region.

The spout can be reclosed and is resealed by means of a screw cap. The thread on the lid matches the threads on the neck. Engagement of the upper surface of the neck and the lower surface of the closure or cover produces the seal.

The cover can also be a reinforcing cover. To be used with external threads such closure or The cover has a plug that hangs down from the inner surface of the closure or cover. This plug will be adjacent to or in contact with the inner surface of the neck. This cap serves to reinforce the neck and to help provide a seal.

As noted the threads on the peak can be internal or external threads. The type of thread will determine the style of cap. When the threads are on the inside surface of the spout the cap will have threads that match on an external surface. Also the lid or cover may have a cylindrical skirt extending down from the top cap surface and in close proximity to the outside surface of the neck to reinforce the neck. When the threads are on an external surface the cover will have threads on an interior surface of the side cover or closure wall. Also preferably the cap will have a plug which extends down from the inner surface to reinforce the wall of the container neck.

In a further embodiment the thermoformed container is made to have a neck reinforced by the material in the neck being of a structure of two or more layers. This is achieved by the sheets of material forming the container being of a structure of two or more layers in the neck region of the container.

These thermoformed containers can be filled in the same way as conventional bottles and used in the same way as conventional bottles. This provides a user-friendly container for consumers at a reduced cost.

Brief Description of the Drawings Figure 1 is a front elevational view of a reclosable thermoformed container.

Figure 2 is a top plan view of the neck of the bottle of Figure 1. - Figure 3 is a top plan view of an alternate container neck.

Figure 4A is a perspective view of a plastic sheet for making a thermoformed container.

Figure 4B is a side elevational view of a single folded sheet of plastic which forms the complete container.

Figure 5 is an elevated view of a thermoformed container with seal ribs.

Figure 6 is an elevated view of a thermoformed container having a neck as in Figure 3.

Figure 7 is a sectional view of the lid of Figure 1.

Figure 8 is an elevated view of a dual chamber thermoformed container.

Detailed description of the invention The reclosable and reusable thermoformed container will be described in greater detail with reference to the Figures. These Figures establish the preferred embodiments of the invention.

Figure 1 shows a thermoformed container in a front elevated view. The container 12 has a surrounding outwardly extending edge 16 and a container neck 14. The neck 14 has an outwardly extending edge 18. The neck also has the threads 20 with these threads aligned with the threads 22 on the neck. outwardly extending edge 18. The upper edge 24 of the neck 14 is preferably planar since this top edge will form a seal with the inner bottom surface of a lid.

This container 12 is closed by means of a lid 26 which has an upper surface 28 and a cylindrical tendon apron 27. The outer surface of this apron is preferably meshed for ease of gripping. Depending on the inner surface of the lid and spacing of the cylindrical apron 27 is a cylindrical reinforcing plug 30 which fits within the container neck 14 and reinforces this part of the container.

Figure 2 is a top plan view of the neck 14 of the container of Figure 1. The threads 20 are "better in this view." Figure 3 describes a variation on the neck of Figure 1. This neck has the sides 32. which have a slight curve and the arched sides 36. Extending from the arched side 32 is the outwardly extending edge 34. The angle A as shown in the Figure is greater than 90 degrees, and preferably is around 93 degrees at about 105 degrees A more preferred angle is around 97 degrees.

Figure 4A shows the plastic sheet 40 which is used to make the longitudinal sections comprising the thermoformed containers. Two sheets are used to form a container. The upper part of the sheet is bent to form a second layer 42. This can be of any multiple layer structure. This part of the sheet will form the neck of the container. The thermoformed containers in an embodiment are made by forming two sheets of plastic in a hollow body. The edges are sealed and the sheets formed to the shape of the mold, preferably by placing the sheets in a mold and blowing the heated air into the mold until the plastic sheets take on the shape of the mold. The edges of the leaves are joined at this time to form the edge that extends outwards. The edges that extend outward when sealed complete the formation of the hollow body container.

Figure 4B shows a plastic sheet that is V-shaped with legs 41 and 43. Each of the legs is overlapped by segments 45. In this embodiment only the folded sheet is used to make the thermoformed container . The fold will be at the bottom of the container with the overlapping segments forming the reinforced upper part of the thermoformed container. The advantage of using this single-leaf technique is that there will not be an edge extending into the bottom of the container. In this way the container can stand on the bottom in the same manner as other containers.

Thermoforming can be used to produce thin-walled hollow bodies. In the present case it is preferred that the body part of the container be thin walled, but the neck part will have a thicker wall. The walls must have sufficient integrity to not deform when the lid is applied or removed from the container. It also must not deform during handling and storage. If it deforms during handling and storage, the container will be prone to runoff. It is for this reason that the upper part of the sheet 40 is in a structure of two layers 42. Here the upper part is bent over the lower part. This part 42 in making the present containers will be the neck 14 of the containers. Even when shown as two layers this can be a section of three or more layers by additional bending over the upper section of the sheet 40.

Figure 5 is a view of a neck of a container wherein in addition to the threads 20 are the ribs 21 and 23 which are designed to make contact with the surface of the cap and produce a better seal. In addition these ribs due to their shape will provide some tightening reinforcement for the neck 14 of the container.

Figure 6 is a perspective view of a bottle which uses the container neck of Figure 3. This Figure shows the thermoformed container 38 with the neck 31. The neck has the sides 32 and 36. The edge extending outwardly 34 essentially surrounds the container except for the bottom edge 33. There is no edge extending outwardly on the bottom of the container so that the container can stand on its bottom surface. Also in this view only one rib 35 is shown to secure a lid. A seal is achieved by contacting the upper edge 37 and the inner surface of a lid. The rib 35 will fit in a recess in the lid to provide a secure hold of the lid to the container.

Figure 7 is a sectional view of the lid of Figure 1. This view shows the structure of the reinforcing cap 30 of the lid together with the threads 25 for attachment to the container.

Figure 8 discloses a dual chamber thermoformed container 50 which has a peripheral edge 52 and opening 54. Internal threads 56 accept the insert 60. This insert has the threads 62 and the opening 64 centered with the lid 66. This insert 60 is a container and a lid. The threads 62 on the lid portion 61 of the insert are accepted within the threads 56 of the container.

Thermoformed containers can be formed from any plastics that can be molded using heat. Suitable plastics are polystyrene, polystyrene with high impact resistance, high density polyethylene. polypropylene of high resistance to melting, acrylonitrile, butidiene, styrene resins and modified polyacrylonitrile resins such as Barex resins. The container described in the Figures can be easily sealed, opened and resealed. This is a very useful feature. In addition, the edge that extends outward in addition to providing some resistance to the container also contains threads to secure a lid. These threads help the main threads on the container neck. In addition to the use of a closure with a stopper hanging downwards it also serves to reinforce the neck of the container.

The invention has been described in its preferred embodiments. There are modifications that can be made to the concepts of these additions. However, such modifications are considered to be within the incorporations of the thermoformed containers present.

Claims (28)

R E I V I ND I C A C I O N S

1. A thermoformed plastic container comprising a first thermoformed longitudinal section and a second thermoformed longitudinal section, an edge extending outwardly along a periphery of said longitudinal sections, said first longitudinal section and said second longitudinal section being joined together as along said edge extending outwards and forming a closed lower end and an open upper end, said open upper end ends in a neck characterized in that the neck is composed of at least a two-layer structure by bending the sheet over itself to form a second stratum or to fold the sheet on itself to form a second stratum.

2. A thermoformed container as claimed in clause 1 characterized in that the edge extending outwardly of said first longitudinal section and said second longitudinal section extends into the neck whereby said collars is therefore reinforced.

3. A thermoformed container as claimed in clause 2, characterized in that the edge extending outwards has threads on it.

4. A thermoformed container as claimed in clause 3, characterized in that the cover is threadedly attached to the neck. _

5. A thermoformed container as claimed in clause 4, characterized in that the lid is in closed engagement with a substantial part of the inner surface of the neck.

6. A thermoformed container as claimed in clause 1 characterized by the neck being closed by a cap threadedly attached thereto.

7. A thermoformed container as claimed in clause 4 characterized in that the lid is a hollow body container.

8. A thermoformed container as claimed in clause 7 characterized by the hollow body container having a lid.

9. A thermoformed container as claimed in clause 1 characterized by the neck having at least one rib on it.

10. A thermoformed container as it is claimed in clause 4 characterized by the lid has an apron, the threads on said lid engage the threads on the outer surface of the neck.

11. A thermoformed container as claimed in clause 1 characterized by said neck has at least one rib on it.

12. A thermoformed container as claimed in clause 5 characterized by said lid having an inner skirt and an outer skirt, threaded on an outer surface of said inner skirt for engaging the threads on an inner surface of the neck, said outer skirt being in close proximity to an outer surface of said neck.

13. A thermoformed container as claimed in clause 1 characterized in that said neck is composed of at least one structure of two layers of a sheet material.

14. A thermoformed container comprising a first longitudinal section and a second longitudinal section, an edge extending outwardly along a periphery of each section, said first longitudinal section and said second longitudinal section being joined along the edge which extends outwardly forming a closed lower end and an open upper end, said open upper end terminating in a neck, said neck having the threads on at least a part thereof including an edge extending outwardly.

15. A thermoformed container as claimed in clause 14 characterized in that said neck is composed of at least one structure of two layers of a sheet material.

16. A thermoformed container as claimed in clause 14 characterized in that said neck is closed by a cap threadedly attached thereto.

17. A thermoformed container as claimed in clause 14 characterized in that said lid has means for reinforcing said neck.

18. A thermoformed container as claimed in clause 15 characterized in that said lid has a stopper hanging from an inner surface thereof, said stopper being in close contact with a substance part of the inner surface of said neck.

19. A thermoformed container as it is claimed in clause 16 characterized in that said closure is a hollow body container.

20. A thermoformed container as claimed in clause 19 characterized in that said hollow body container has a lid.

21. A thermoformed container comprising a first longitudinal section and a second longitudinal section, an edge extending outwardly along the periphery of each section, said first longitudinal section and said second longitudinal section being joined along the edge which is extends outwardly forming a closed lower end and an open upper end, said open upper end terminating in a neck of at least one rib and a recess on at least a portion of said neck.

22. A thermoformed container as claimed in clause 21 characterized by said peak is closed by a lid having at least one rib and a recess thereon to coincide with at least one rib and a recess of said neck.

23. A thermoformed container as claimed in clause 21 characterized in that said lid has means for reinforcing said neck.

24. A thermoformed container as claimed in clause 21 characterized in that said neck is composed of at least one structure of two strata of a sheet material comprising said first longitudinal section and said second longitudinal section.

25. A thermoformed container as claimed in clause 21 characterized by said neck is composed of at least one structure of two strata of a hoa material.

26. A thermoformed container as claimed in clause 23 characterized in that said reinforcing means is a plug that hangs down from said lid into the container.

27. A thermoformed container as claimed in clause 3 characterized by said closure is a hollow body container.

28. A thermoformed container as claimed in clause 27 characterized in that said hollow body container has a lid. SUMMARIZES The thermoformed containers present are resealed and can be reclosed. This is achieved primarily by providing a thermoformed container with a threaded neck and the use of a conventional type of closure on the threaded neck of the texmoformed container. The threads are on the neck and preferably also on a peripheral edge that extends outwardly on the neck. This peripheral edge that extends outwards is created in thermoforming molding. The neck preferably also is in the form of a structure of two or more layers and in an additional preferred embodiment the neck is reinforced by the cover. The cap in the incorporation of external threads on the neck has a reinforcing plug 30. In this embodiment the reinforcing plug fits within the neck adjacent to the inner wall of the neck while the threads of the lid make contact with the outer wall of the neck. In the incorporation of the internal threads on the neck the cover can have a skirt which is in close contact with the outer wall of the neck. This will reinforce the neck in a similar way. The neck can take many forms from the cylindrical to approaching a rectangular shape.