Thermal gel packs that include a gelatinous material are used for maintaining a cool or hot state for extended periods of time. Cool packs in particular have been used for preserving perishable items being shipped (e.g., in boxes, crates or Styrofoam containers) in a cool state. The gel pack is refrigerated to a frozen state prior to putting the gel pack in the shipping container. Some gel packs come pre-filled with the gelatinous material prior to being used by the customer that is shipping the products. However, these pre-filled gel packs are expensive to transport to the customer due to their size and weight.
Therefore, there is a need in the art for improved methods and systems for providing shipping products with thermal and mechanical insulation features.
According to the present invention, methods and systems related to packaging structures are provided. More particularly, embodiments of the present invention provide a fillable gel pack that includes an inner sealed chamber containing gel in powder form. Upon filling with water, the fillable gel pack is suitable for use in cold/frozen packaging applications. The methods and systems described herein can be applied to other applications as well, including heated applications. A variety of users can benefit from the embodiments described herein, including businesses that ship perishable or temperature sensitive products, end user transporting perishable products in coolers or other containers, and the like.
According to an embodiment of the present invention, a fillable gel pack is provided. The fillable gel pack includes a first film layer having an area and a liquid permeable layer bonded in a region equal to or smaller than the area of the first film layer to define a gel chamber. The fillable gel pack also includes a gel material disposed in the gel chamber and a second film layer bonded to at least a portion of the liquid permeable layer or the first film layer to define a liquid chamber.
According to another embodiment of the present invention, a fillable gel pack is provided that includes a first and second layer joined together to define an exterior surface of the fillable gel pack and a fill port leading into a first interior portion of the fillable gel pack. The first and second layers are formed of a material that is generally impermeable to liquids. The first and second layers can also be referred to as non-permeable layers. Due to the material properties of the first and second layers, any liquids introduced into the fillable gel pack are prevented from escaping the gel pack through either of the first and second layers. The fillable gel pack also includes a liquid permeable layer that separates the first interior portion from a second interior portion that contains powdered gel material. When a liquid is introduced into the first interior portion of the fillable gel pack through the fill port, the liquid can then enter the second interior portion by passing through the liquid permeable layer. Once inside the second interior portion, the liquid can be absorbed by the powdered gel material, which then expands as the gel material absorbs the liquid. After absorbing the liquid, the gel material and absorbed water remain firmly secured within the second interior portion, thereby preventing liquid from subsequently leaking back out of the fillable gel pack during transit.
Numerous benefits are achieved by way of the present invention over conventional techniques. For example, embodiments of the present invention provide customers with a gel pack that is delivered to the customer in a low profile, low weight package. The gel pack includes a sealed gel chamber that encloses a gel material during shipping and prevents the gel material from escaping the gel pack. Although the gel chamber is sealed with respect to the gel material, it is permeable to liquids for subsequent filling. When ready for use, the customer can fill the gel pack with a liquid that gels the enclosed gel material and then freeze the gel pack for use during shipping of product. These and other embodiments of the invention along with many of its advantages and features are described in more detail in conjunction with the text below and attached figures.
As illustrated in
As illustrated in
Top film layer 210 and the bottom film layer 212 can be a formed from a variety of coextruded multilayer films or monolayers. As an example, these layers can include, nylon, LDP (low density polyethylene), or combinations thereof. The peripheral seal can be formed by heat treatment or by lamination with a glue or adhesive. The outer surfaces of the film layers can be treated as appropriate for later printing on these surfaces.
A liquid permeable layer 218 is provided to enclose and seal a predetermined quantity of a hydratable gel material 220. The liquid permeable layer 218 in the depicted embodiment can be bonded to at least one of the top film layer 210 and the bottom film layer 212. By bonding liquid permeable layer 218 in this manner liquid permeable layer 218 can create an interior portion referred to as a gel chamber in cooperation with one of the film layers so that the hydratable gel material remains confined within the fillable gel pack. The hydratable gel material 220, which can also be referred to as a dehydrated gel material, can be sodium polyacrylate or some other polymer or copolymer containing acrylic acid or acrylamide monomers, as well as polymers of acrylamide. Using gel material in dry or powder form provides both mechanical and physical benefits based on the characteristics of the gel material in dry form over the gel material in wet form. For example, benefits of the use of gel material in dry form include a decrease in shipping volume since the gel material can have a shipping volume of less than 0.1 ounce compared to 24 ounces when gelled. Thus, in terms of physical volume, embodiments of the present invention provide a product that is less than ⅛″ in thickness compared to a thickness greater than or equal to 1″ for conventional gelled products. The entrapment of the gel material 220 between material that is substantially impermeable to the movement of the gel material 220 prevents leaking of the gel during shipping. As described herein, liquid permeable layer 218 is permeable to water or other liquids, enabling gelling of the gel material when ready for use. Moreover, the gel material can be transformed into a gelled state without being submerged in a large body of water. Rather, embodiments of the present invention enable the user to add liquid into fillable gel pack 100 through fill port 102 using just enough water to gel the gel material. When the liquid enters through fill port 102 it enters an interior portion of fillable gel pack 100 defined on one side by top film layer 210 and on another side by liquid permeable layer 218. The liquid entering the first interior portion then passes through liquid permeable layer 218 and then interacts with gel material 220 at which point the liquid absorbed by gel material 220 is now trapped within the fillable gel pack. Accordingly, using embodiments of the present invention, one characteristic of the gel pack once formed compared to conventional systems is that no air bubble is formed during the freezing process or during the thawing process, since air can pass into and out of the fillable gel pack by way of fill port 102.
The liquid permeable layer 218 can be formed of any of a number of materials arranged in a permeable configuration including, for example, polyethylene, polyester, nylon, polypropylene, polyurethane and rayon. In some embodiments, these materials can be spun into a web to form a nonwoven spunbond cloth that is permeable to water, allowing water to flow through the gel chamber layer and make contact with the hydratable gel. In one particular embodiment, liquid permeable layer 218 can be a layer of nonwoven spunbond formed entirely of polypropylene and having a thickness of between about 100 and 200 microns. In other embodiments, liquid permeable layer 218 can be formed from a layer of film defining a perforated nano-grid that allows the passage of liquids while blocking solids with a particulate size greater than or equal to the particulate size of the powdered gel material.
As depicted, the gel material 220 is placed between the liquid permeable layer 218 and the bottom film layer 212 prior to heat sealing such that the gel material is sealed between the bottom film layer and the gel chamber layer during heat sealing. As an example, the gel material can be measured and dispensed by a powder dispenser before the layers are heat sealed to form the gel chamber between the gel chamber layer and the bottom film layer. This dispensing of the powder between the layers can be integrated into a larger manufacturing process that includes unwinding each of a number of layers of raw materials in roll stock form and heat sealing or otherwise joining all the raw material layers together in a predetermined pattern. In some embodiments, the aforementioned powder addition between the liquid permeable layer 218 and bottom film layer 212 can be automated. An automated process can be implemented when the unwinding of the raw material layers is conducted in a vertical orientation that allows the gel material 220 to be dropped between liquid permeable layer 218 and bottom film layer 212 prior to lamination of the layers.
Herein, reference is made to the liquid permeable layer as “sealing” the gel material in the region between the gel chamber layer and the bottom film layer, which can be referred to as the gel chamber. The liquid permeable layer is permeable to water and other liquids, but not significantly permeable to the gel material in either its powdered state nor its hydrated state. Thus, after heat sealing, the gel material is prevented from escaping the gel chamber. The sealing of the gel material in the gel chamber prevents problems associated with conventional designs in which the gel material was loose and able to pass through the fill port during transport or use. However, although the gel material is substantially prevented from escaping the gel chamber, the liquid is able to enter into the gel chamber and interact with the gel material, which is also prevented from escaping the gel chamber.
In some embodiments, the top film layer 212, the liquid permeable layer 218, and the bottom film layer 212 have the same lateral dimensions (i.e., width and length) as illustrated in
In a typical use case, the fillable gel pack is shipped to the user in a substantially flat form since the gel material is in powder form. During shipping, the gel material remains in the gel chamber and is prevented from spilling from the fillable gel pack. When ready for use, the gel material is hydrated by adding liquid (e.g. water) through the fill port, which subsequently passes through the liquid permeable layer. Typically, the fillable gel pack is filled with a defined volume of water to transform the powdered gel material into a gel of predetermined volume. In some use cases, the fillable gel pack is maintained in a vertical position for a predetermined amount of time (e.g., two minutes) to enable the water to enter the gel chamber through the gel chamber layer, which is permeable to water but not to the gel material. After the liquid is all absorbed by the powdered gel material, the fillable gel pack can be frozen for subsequent use, for example, by laying the filled gel pack flat in a freezer. Embodiments of the present invention provide systems not available using conventional techniques, including quick gel times. As described herein, the liquid permeable layer entraps the gel material in the gel chamber, but does not provide mechanical support for the gel pack. Accordingly, the gel material layer can utilize larger pores than found in conventional systems, enabling relatively higher flow rates as the liquid enters the gel chamber. At the same time, the larger pore sizes, which would typically result in tearing of the encasing material in a stand-alone design, do not impact the mechanical performance since the outer film layers provide protection and support for the liquid permeable layer.
In contrast with conventional packages, the fillable gel pack design prevents the formation of air bubbles in the gel pack since the gelling process enables the volume inside the pouch to remain the same after gelling and at later points in time, up to and through freezing of the gel pack. The fill port enables air to escape as the gelling and subsequent freezing processes are performed, reducing or eliminating air bubbles from forming within the finished package. Moreover, embodiments of the present invention provide benefits not available using conventional techniques. As an example, gelling time can be separated from filling time since for gels that take longer to gel than the time needed to fill the gel pack, the gelling process can continue after filling since the water is confined to the interior portions of the gel pack by the top film layer and the bottom film layer. Thus, embodiments of the present invention provide benefits not available using gel material separate from the fillable gel pack.
Although the outer edges of the layers illustrated in
In the embodiment illustrated in
The gel chamber heat seal pattern 320, which is used to bond liquid permeable layer 322 to the bottom film layer 314 and define a gel chamber that encloses gel material 324, has an area that is smaller than the area of the bottom film layer 314. In this embodiment, the periphery and area of the gel chamber heat seal pattern 320 are equal to the periphery and area of the liquid permeable layer 322. In other embodiments, the width of the liquid permeable layer 322 and the bottom film layer 314 (measured across the shorter dimension) are equal, but the length of the liquid permeable layer is less than the length of the bottom film layer 314, extending in some implementations up to the bottom portion of the cutout 318. In these embodiments, the area of the gel chamber is less than the area of the bottom film layer 314, providing a finished product that has a gel chamber smaller than the outer area.
In particular
It is also understood that the examples and embodiments described herein are for illustrative purposes only and that various modifications or changes in light thereof will be suggested to persons skilled in the art and are to be included within the spirit and purview of this application and scope of the appended claims.
The present application claims the benefit of U.S. Provisional Application No. 62/039,841, filed on Aug. 20, 2014, the disclosure of which is hereby incorporated by reference.
Number | Date | Country | |
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62039841 | Aug 2014 | US |