MXPA97010086A - Composite package structure to contain items, and method for your production - Google Patents

Abstract

The present invention relates to a method for producing a composite package for containing articles, wherein this method is comprised of the steps of: forming a sheet of polymeric material in a web of a plurality of polymeric trays; coating a first side of an element of cardboard cover with a heat-sealable coating at low temperature, placing the coated cardboard cover element substantially on one of the plurality of polymeric trays, with the coating located adjacent to one of the trays, securing said tray from the plurality of polymeric trays to the coated cardboard cover element at an initiation temperature of less than 93 ° C (200 ° F), to form an intermediate composite package, trimming the intermediate composite package to form a final coupled-edged composite package, inserting an article substantially inside the final composite package, and retain this article substantially tro of the compound package end

Description

COMPOSITE PACKAGE STRUCTURE TO CONTAIN ITEMS, AND METHOD FOR YOUR PRODUCTION BACKGROUND OF THE INVENTION Field of the Invention This invention relates to package structures made of cardboard and plastic that combine an intricate thermoformed cover with a cardboard base or cover. Structures of this type generally provide a lightweight package with a good surface for printing on the outside of the package. Description of the Related Art In composite package structures, it is known to make use of a book-shaped container cardboard cover and an internal plastic tray. An example of these structures is United States Patent Number 4,724,957 ('957), from 0. Burgsch eiger, entitled "Container". Although the '957 patent teaches a cardboard cover and an inner plastic tray, the cover is not connected to the inner tray along the spine. Also, sheet is located on the outer side of the cover. It can be seen that, if the inner tray were linked with the cardboard cover along the length of the spine, a greater rigidity of the package would result. Also, if the foil cover was removed, a wider range of printed graphics could be used. Consequently, a more convenient container would then be presented if the stiffness and the range of printed graphics were increased. In the composite packages, it is also known to make use of an internal molded tray and an outer cover. An example of this prior art is U.S. Patent Number 4,635,797 ('797) to J.D. Bankier, entitled "Pilfer Resistant Software Package". Although the '797 patent teaches the use of a package of cardboard and composite plastic, the inner plastic tray is welded to the cardboard cover by conventional RF techniques along the peripheral flange. The use of RF techniques at high temperature can cause deformation by temperature of the thermoformable inner tray. Accordingly, an even more convenient composite package would then be presented if a low temperature heat sealable coating was used. From the foregoing, it can be seen that there is a need in the art for a composite package that is rigid, and that can employ a wide range of printed graphics, but at the same time, eliminate the use of high temperatures. It is a purpose of this invention to satisfy this and other needs in the art, in a manner more apparent to the skilled person once the following description is given.

SUMMARY OF THE INVENTION Broadly speaking, this invention meets these needs by providing a composite package for containing articles, which comprises a cardboard base having first and second sides, a layer of particulate minerals located outside the first side of the cardboard base, a layer of a heat-sealable polymeric material at a low temperature, located outside the second side of the cardboard base, and a thermoformable polymeric cover having first and second sides, such that the first side of the base the cover is rigidly bonded to the heat sealable polymeric material, and the articles are located substantially adjacent to the second side of the cover. In certain preferred embodiments, the particulate minerals are clay. Also, the low temperature heat sealable polymeric material is a polyethylene (PE) coating and an ethylene-methylacrylate copolymer (EMA). Also, the thermoformable cover is constructed of polystyrene or a similar plastic material. Finally, a cardboard lid can be used to cover an opening in the composite package. In yet another preferred embodiment, the structure of the composite package provides a light weight package with a good surface for printing on the outside of the package.

The preferred composite package, in accordance with this invention, offers the following advantages: light weight; the use of a wider range of printed graphics; greater rigidity; lower manufacturing temperatures; good stability; good durability; and good economy. In fact, in many of the preferred modalities, these lightweight factors, a wider range of graphs, higher stiffness and lower temperatures, are optimized to the extent that they are considerably higher than what has been achieved so far in the above known composite packages. The foregoing and other features of the present invention, which will become clearer as the description proceeds, are best understood by considering the following detailed description in conjunction with the accompanying drawings, in which like characters represent equal parts through of the different views, and in which: BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a method for producing a composite package, in accordance with the present invention. Figure 2 is a side view separated into parts of the composite package according to the present invention. Figure 3 is a side view of another embodiment of the composite package according to the present invention. Figure 4 is a side view of yet another embodiment of the composite package according to the present invention. Figure 5 is a side view of the composite package constructed of Figure 2 and folded, in accordance with the present invention. DETAILED DESCRIPTION OF THE DRAWINGS Referring first to Figure 1, a system 2 for manufacturing a composite package 22 is illustrated. In particular, the system 2 includes, in part, the thermoformable polymer roll 4, the thermoformable polymer sheet 6, the conventional thermoformer 8, the thermoformed polymer trays 10, the conventional feeder 12, the cardboard bases or covers 14, the conventional heat sealant 16, the intermediate composite packages 18, the conventional trimmer 20, and the composite packages 22. roll 4 and sheet 6 of thermoformable polymer, preferably, are constructed of polystyrene or any suitable plastic material that can be thermoformed to create an internal tray configured to engage the product of interest. The bases or cardboard covers 14, preferably include a coating 30 (Figure 2) of particulate minerals on one side, and a coating 24 (Figure 2) of a polymeric material heat sealable at low temperature on the other side. The particulate minerals are preferably clay. The low temperature heat sealable polymeric material is preferably a polyethylene (PE) coating and an ethylene-methylacrylate copolymer (EMA), which has an initiation temperature of less than 60 ° C (140 ° F) and a Vicat softening point less than 54.4 ° C (130 ° F). It should be understood that the coating 24 can be applied to the base or cover 14 by conventional techniques, such as coextrusion. During the construction of the composite packages 22, the roll 4 is unwound, in such a way that the sheet 6 is formed. The sheet 6 is transferred through the thermoformer 8, in such a way that a screen of trays 10 is produced. that a screen of trays 10 is produced, the base or cardboard cover 14 is placed on one side of the trays 10, in such a way that the cover 24 (Figure 2) is adjacent to the tray 10. After the base or the cardboard cover 14 on the tray 10, the tray 10 and the base or the cover 14 are heat sealed in the heat sealant 16, so that an intermediate package 18 is produced. Then the intermediate package 18 is transfers to the trimmer 20, in such a way that a composite package 22 is formed. With respect to Figure 2, it is illustrated in more detail, the final construction of the composite package 22. In particular, the composite package 22 includes, in part, the thermoformed polymer tray 10, the cardboard base or cover 14, the low temperature heat sealable coating 24, the flange 26, the marked lines 28, and the particulate coating 30. The coating 24 is preferably the same low temperature heat sealable coating 24 as described above. Also, the coating 30 is the same coating 30 as described above. Finally, the marked lines 28 are placed on the base or cardboard cover 14 in order to provide the desired flexibility inside the base or cardboard cover 14. However, it should be understood that marked lines may be omitted in certain cases. 28. In order to secure the items inside the package 22, the package 22 is oriented in such a way that the items are placed in a section of the tray 10. The other section of the tray 10 is then folded in the manner of a book, along the marked lines 28, and engages with the section of the tray 10 containing the articles. In this way, the articles are retained inside the tray 10 and the package 22. Also, the end user is free to place printed graphics on the base or the cover 14. Figure 3 illustrates another embodiment of a composite package 50. In in particular, the composite package 50 includes, in part, the base or cardboard cover 52, the low temperature heat sealable coating 54, the thermoformed polymer tray 56, the flange 57, the cardboard cover 58, the seal coating by low temperature heat 60 and particulate coating 62. It should be understood that coatings 54 and 60 are preferably constructed of the same materials as coating 24 (Figure 2). Also, the coating 62 is preferably constructed of the same materials as the coating 30 (Figure 2). The composite package 50 is constructed in substantially the same manner as the composite package 22. In particular, the tray 56 is thermoformed in the thermoformer 8 (Figure 1). The base or cardboard cover 52 is then placed on the tray 56, and heat sealed to the tray 56 by the heat sealer 16 (Figure 1). After the tray 56 is heat sealed to the base or cover 52, then the intermediate packages are trimmed on the trimmer 20 (Figure 1). After the trimming is done, an article (not shown) is placed inside the tray 56, such as food, and then the lid 58 is heat sealed to the flanges 57, such that a composite package 50 is formed. Figure 4 shows yet another embodiment of a composite package 100. The composite package 100 includes, in part, the base or cardboard cover 102, the low temperature heat sealable coating 104, the thermoformed polymer tray 106, the cover of cardboard 108, the low temperature heat sealable coating 110, and the flanges 112, and the particulate coating 114. The coating 104 is preferably the same as the coating 24 of Figure 2. The coating 110, is preferably any suitable heat-sealable coating that is properly bonded to the cardboard flanges 112. Finally, the coating 114 is preferably constructed of the same materials as the coating 30 (Figure 2). The construction of the composite package 100 is substantially similar to the construction of the composite package 50. In particular, the tray 106 is thermoformed. The base or cover 102 is then heat sealed to the tray 106. The articles are placed inside the tray 106. Finally, the lid 108 is then heat sealed to the flanges 112. Finally, Figure 5 shows the composite package 22 in a folded form. In particular, the package 22 is folded along the marked lines 28, such that the coupling sections of the polymer tray 10 engage with each other, for the purpose of retaining items (not shown) inside the package 22, after the package 22 is folded.

Once given the previous description, the expert will be able to see many other characteristics, modifications or improvements. Accordingly, it is considered that these features, modifications or improvements are part of this invention, the scope of which should be determined by the following claims.

Claims (11)

1. NOVELTY OF THE INVENTION Having described the foregoing invention, it is considered as a novelty and, therefore, the content of the following is claimed as property: CLAIMS 1. A method for producing a composite package for containing articles, wherein this method it is comprised of the steps of: forming a sheet of polymeric material in a web of a plurality of polymeric trays; coating a first side of the cardboard cover element with a heat-sealable coating at a low temperature, - placing the coated cardboard cover element substantially on one of the plurality of polymeric trays, with the coating located adjacent said tray; securing said tray from the plurality of polymeric trays to the coated cardboard cover element, to form an intermediate composite package; trimming the intermediate composite package to form a final composite package; inserting an article substantially inside the final composite package; and retain this article substantially within the final composite package. The method according to claim 1, characterized in that the step of forming is further comprised of the step of: thermoforming the sheet of polymeric material. 3. The method according to claim 1, characterized in that the polymeric material is also comprised of: polystyrene. 4. The method according to claim 1, characterized in that the heat-sealable coating is further comprised of: a coextrusion of polyethylene and an ethylene-methylacrylate copolymer. 5. The method according to claim 1, characterized in that the method is further comprised of the step of: coating a second side of the cardboard cover element with a layer of particulate minerals. 6. The method according to claim 5, characterized in that the particulate minerals are also comprised of: clay. The method according to claim 1, characterized in that the step of securing is further comprised of the step of: heat sealing the cardboard covers to said tray of the polymeric trays. 8. The method according to claim 1, characterized in that the step of retaining is further comprised of the step of: folding the final composite package. 9. The method according to claim 1, characterized in that the method is further comprised of the step of: securing the lid element having first and second sides, substantially on one of the plurality of polymeric trays. The method according to claim 9, characterized in that the lid element is further comprised of: a low temperature heat sealable coating located outside the first side of the lid element and substantially facing one of the plurality of polymeric trays. 11. The method according to claim 9, characterized in that the lid element is further comprised of: a coating of particulate minerals located outside the second side of the lid element.