Patent Application
20060013514
The present invention generally relates to vacuum packaging. More particularly, the invention is directed to vacuum packaging bags with gussets and methods for using and manufacturing vacuum packaging bags with gussets.
Vacuum packaging involves removing air or other gases from a storage container and then sealing the container to prevent the contents from being exposed to ambient air. Vacuum packaging is particularly useful in protecting food and other perishables against oxidation. Oxygen is a main cause of food spoilage and contributes to the growth of bacteria, mold, and yeast. Accordingly, vacuum-packaged food often lasts three to five times longer than food stored in ordinary containers. Moreover, vacuum packaging is useful for storing clothes, photographs, silver, and other items to prevent discoloration, corrosion, rust, and tarnishing. Vacuum packaging also produces tight, strong, and compact packages, reducing the bulk of articles and allowing for more space to store other supplies.
Conventional vacuum packaging bags include two panels attached together with an open end. Typically, the panels each include two or more layers. The inner layer can be a heat sealable material, and the outer layer can be a gas impermeable material to provide a barrier against the influx of air. The plasticity temperature of the inner layer is lower than the outer layer. As such, the bag can be heated to thermally bond the inner layer of each panel together to seal the bag without melting or puncturing the outer layer.
A conventional vacuum packaging process includes depositing the object 98 into the bag 60 and positioning an open end 62 of the bag 60 in the lower trough 22 of the vacuum packaging appliance 10. Next, the lid 40 pivots downward to form the vacuum chamber with the open end 62 of the bag 60 disposed within the vacuum chamber. The vacuum pump then removes gas from the vacuum chamber and the interior of the bag 60, which is in fluid communication with the vacuum chamber. After gas has been removed from the interior of the bag 60, the heating element 30 heats a strip of the bag 60 proximate to the open end 62 to bond the inner layer of each panel together and thermally seal the bag 60.
One problem with conventional vacuum packaging bags is that bags configured to store bulky objects have big panels, which require a large vacuum packaging appliance to evacuate and seal. Large appliances have relatively big footprints and consume significant space on a countertop or other surface. For example, the footprint of the appliance 10 illustrated in
A. Overview
The present invention is directed toward vacuum packaging bags and methods of manufacturing and using vacuum packaging bags. In one embodiment, a vacuum packaging bag includes a first panel, a second panel coupled to the first panel, and a gusset between the first and second panels. The first panel has a first gas impermeable layer and a first sealable layer coupled to the first gas impermeable layer. The second panel has a second gas impermeable layer and a second sealable layer coupled to the second gas impermeable layer. The gusset can extend along a length of the bag and project inwardly toward an interior region.
In another embodiment, a vacuum packaging bag includes a first panel and a second panel coupled to the first panel. The first panel has a plurality of intercommunicating channels, a first edge, a second edge opposite the first edge, a first gas impermeable layer, and a first sealable layer coupled to the first gas impermeable layer. The second panel has a third edge, a fourth edge opposite the third edge, a second gas impermeable layer, and a second sealable layer coupled to the second gas impermeable layer. The bag further includes a first gusset between the first and third edges and a second gusset between the second and fourth edges. In one aspect of this embodiment, the sealable layers are formed of a material such that the first sealable layer pealably bonds with the second sealable layer under the influence of heat and/or pressure. The sealable layers may also be formed of a material such that the first sealable layer permanently bonds with the second sealable layer.
The following disclosure describes several embodiments of vacuum packaging bags and methods of manufacturing and using vacuum packaging bags. Several details describing structures and processes that are well known and often associated with vacuum packaging appliances and bags are not set forth in the following description for purposes of brevity. Moreover, although the following disclosure sets forth several embodiments of different aspects of the invention, several other embodiments of the invention can have different configurations or different components than those described in this section. As such, it should be understood that the invention may have other embodiments with additional elements or without several of the elements described below with reference to
B. Embodiments of Vacuum Packaging Systems Including Vacuum Packaging Bass and Vacuum Packaging Appliances
The vacuum packaging appliance 110 further includes a vacuum pump 130 (shown in broken lines) operably coupled to the first and/or second chamber portion 122 or 142 for removing gas from the vacuum chamber when the lid 140 is in the closed position. The vacuum pump 130 can also remove gas from the interior of the bag 160 when an open end 162 of the bag 160 is positioned in the vacuum chamber. The bag 160 is configured so that the interior of the bag 160 is in fluid communication with the vacuum chamber when the lid 140 is in the closed position, as described in greater detail below with reference to
In the illustrated embodiment, the vacuum packaging appliance 110 further includes a heating element 135 and a member 155 for pressing the bag 160 against the heating element 135. The heating element 135 can be carried by the base 120, and the member 155 can be carried by and project from the lid 140. The heating element 135 is configured to thermally seal the bag 160 after the gas has been substantially evacuated from the interior of the bag 160. The heating element 135 heats the bag 160 and the member 155 presses the bag 160 against the heating element 135 to ensure a seal is formed across the bag 160. In other embodiments, the vacuum packaging appliance 110 can have a different configuration.
C. Embodiments of Vacuum Packaging Bags Having Gussets
The illustrated vacuum packaging bag 160 further includes a gusset 190 between the first and second panels 164 and 174. The gusset 190 has a first portion 191a attached to the first panel 164 at the first edge 168a and a second portion 191b attached to the second panel 174 at the first edge 178a. The illustrated gusset 190 extends along a length L of the bag 160 and projects inwardly toward the interior region 184 when the bag is empty. In other embodiments, such as the embodiments described below with reference to
One advantage of the illustrated bag 160 is that the gusset 190 increases the storage capacity of the bag 160. The storage capacity is increased because the gusset 190 allows the first and second panels 164 and 174 to move a greater distance apart from each other. More specifically, as objects are placed into the interior region 184, an angle α between the first and second portions 191a-b increases and the gusset 190 moves in a direction D1 so that the first and second panels 164 and 174 can move away from each other. As such, the bag 160 can carry a greater volume of objects. Although the storage capacity of conventional bags can be increased by increasing the size of the panels, the larger panels require a bigger vacuum packaging appliance to evacuate and seal the bag. Bigger vacuum packaging appliances have larger footprints and require more space on the countertop or other surface. The gusset 190 in the illustrated bag 160, however, increases the storage capacity of the bag 160 without increasing the size of the panels. Consequently, the bag 160 can be evacuated and sealed by an appliance with a smaller footprint.
Another feature of the illustrated bag 160 is that as an object is placed into the bag 160 and the first and second panels 164 and 174 move apart, the first and second panels 164 and 174 remain generally flat and, consequently, the footprint of the first and second panels 164 and 174 does not change significantly. An advantage of this feature is that the generally flat panels are easier to seal together in a vacuum packaging appliance. In contrast, when an object is placed in a conventional bag that does not have a gusset, the panels curve to increase the interior volume of the bag and, consequently, the footprint of the panels is reduced. The open end of these conventional bags is more difficult to seal.
The sealable layers 182 can include a pealably sealable layer and/or a substantially permanently sealable layer. The pealably sealable layer includes resin or other materials that through pressure, heat, or another sealing enabler, form a pealable seal that is opened through a manual pealing action. The manual pealing action does not require a tool and does not result in wasting or destroying a portion of the vacuum packaging bag. Pealably sealable layers are described in detail in U.S. Provisional Patent Application No. 60/553,693, filed Mar. 15, 2004, which is incorporated by reference herein. Permanently sealable layers can include resin that with heat forms a generally permanent seal. In several embodiments, the sealable layers 182 can include a material which when heated to a first temperature forms a pealable seal and when heated to a second temperature forms a permanent seal.
In the illustrated embodiment, the second panel 174 includes a plurality of intercommunicating channels 175 configured to exhaust gas from the interior of the bag 160 when the first and second panels 164 and 174 are pressed together as shown in
As the side-gusseted portion of the bag has additional bag material, sealing tends to require more energy than bags not having the extra thickness of the side-gussets. This is not a difficult problem to compensate for, simply meaning that more energy must be used and perhaps users should be aware of this requirement to ensure that seals are properly made. Additionally, the side-gusseted bag may best be made from PE or PP materials as these seal more readily than competing nylon materials. However, any suitable material may be used as long as the proper care is taken.
From the foregoing, it will be appreciated that specific embodiments of the invention have been described herein for purposes of illustration, but that various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.
