SHIPPING PACKAGE WITH PHASE-CHANGE MATERIAL

Abstract

A shipping package includes an envelope including a closed end and a closeable end. The envelope defines a thermal control space and an interior space that is separate from the thermal control space. The internal space is configured to contain a product to be shipped. The shipping package further includes a first phase-change material mat positioned within the thermal control space and adjacent the interior space, a first thermally insulative sheet positioned within the thermal control space and adjacent the first phase-change material mat, and a second phase-change material mat positioned within the thermal control space and adjacent first thermally insulative sheet. The shipping package provides a thermally controlled interior space to protect temperature-sensitive products from environmental conditions.

Description

BACKGROUND

Shipping is a worldwide industry. Shippers and their customers are typically concerned with delivery time and cost. However, many products require additional attention. Certain types of products, such as drugs, pharmaceutical products or components, food, lab samples, and medical supplies or materials, may require temperature control during shipping. Often such products need to be kept cool, at a stable temperature that is lower than the nominal temperature of the environment. Freezer ice packs, ice, dry ice, and other techniques have been used to solve this problem.

SUMMARY

According to an aspect of this disclosure, a shipping package includes an envelope including a closed end and a closeable end. The envelope defines a thermal control space and an interior space that is separate from the thermal control space. The internal space is configured to contain a product to be shipped. The shipping package further includes a first phase-change material mat positioned within the thermal control space and adjacent the interior space, a first thermally insulative sheet positioned within the thermal control space and adjacent the first phase-change material mat, and a second phase-change material mat positioned within the thermal control space and adjacent first thermally insulative sheet.

The first phase-change material mat, the first thermally insulative sheet, and the second phase-change material mat may form an arrangement that is positioned on a first side of the interior space. The shipping package may further include another such arrangement positioned on a second side of the interior space.

The shipping package may further include a second thermally insulative sheet positioned within the thermal control space and adjacent the second phase-change material mat.

The shipping package may further include an additional thermally insulative sheet positioned within the thermal control space and adjacent the interior space.

The additional thermally insulative sheet may be positioned to maintain a size of the interior space.

The first thermally insulative sheet may include rigid segments with a strip of flexible material therebetween.

One or more of the first and second phase-change material mats may include a rigid shell containing phase-change material.

One or more of the first and second phase-change material mats may include a flexible bag containing phase-change material.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of an example shipping package according to the present disclosure.

FIG. 2A is a side cross-sectional view of the example shipping package of FIG. 1 along section line A-A.

FIG. 2B is a front cross-sectional view of the example shipping package of FIG. 1 along section line B-B.

FIG. 3 is a perspective view of the example shipping package of FIG. 1 when open.

FIG. 4 is a perspective view of another example shipping package with multiple closures according to the present disclosure.

FIG. 5A is a plan view of an example phase-change material mat according to the present disclosure.

FIG. 5B is a plan view of another example phase-change material mat according to the present disclosure.

FIG. 5C is a plan view of another example phase-change material mat according to the present disclosure.

FIG. 6A is a side cross-sectional view of another example shipping package.

FIG. 6B is a front cross-sectional view of the example shipping package of FIG. 6A.

FIG. 7 is a side view of another arrangement of thermally insulative sheets and phase-change material mats.

FIG. 8 is a plan view of another example thermally insulative sheet.

DETAILED DESCRIPTION

Existing techniques to provide temperature control to shipped products suffer from a number of problems. Ice, freezer packs, and similar articles are typically dropped into a regular shipping box or envelope with the product to be shipped. This can result in an uneven temperature profile in the package, which may cause the product to get too hot or too cold, or leakage, which may contaminate the product. Another technique is a box with walls that has interior panels containing gel or other material. Aside from being complicated, and thus costly, this solution is difficult to store when not in use, sometimes requiring disassembly. It may take up more space than necessary and thus increase storage and shipping costs.

Discussed herein are techniques to address these and other problems. As will be discussed below, a shipping package includes a double-walled envelope with mats of phase-change material between the walls. The double-wall means that leakage of phase-change material is less likely to contaminate the product. A thermally insulative sheet may also be provided in the inter-wall space. The sheet may provide structure to the envelope to protect the product while also providing insulation. At the same time, phase-change material may be provided in mats (panels) having cells that allow for some flexibility, so as to conform to the shape of the package and avoid leakage which may result from overstress. The techniques also include color-coding the packages and components thereof to simplify the selection of a package for a specific shipment. In addition, a series of closures may be provided to the package to provide for limited reuse. These techniques simplify construction and usage of a shipping package and also increase the thermal efficiency of such. Further, increased user convenience may also be realized.

FIG. 1 shows an example shipping package 100 that uses phase-change materials to control the temperature inside the package 100. The shipping package 100 may be used to transport products that are temperature sensitive and/or require temperature stability, particularly at temperatures lower than the surrounding environment. Examples of such products include drugs, pharmaceutical products or components, food, lab samples, medical supplies/materials, and similar. In this figure, the package 100 is shown closed.

The shipping package 100 includes an envelope 102. Most or all of the envelope 102 is double walled, with the outer wall being visible in FIG. 1. In various examples, the space between the walls of the envelope 102 contain phase-change material and insulation to provide temperature control to the interior of the package 100. The envelope 102 may be generally rectangular, as depicted, or have another shape.

The envelope 102 is closed along two sides 104, 106 and a closed end 108 and further includes a closure 112 at an open end 110 that is closeable. The closure 112 may include a flap of envelope material with a permanent or semi-permanent closure mechanism, such as an adhesive strip, glue, a surface for applying adhesive or glue, or similar. The closure 112 may include a reusable closure mechanism, such as hook-and-loop strips (e.g., Velcro™), a grommet and string tie-off arrangement, a snap, or similar. Multiple of the same of different closure 112 may be used. For instance, in some examples, multiple adhesive strips may be provided to allow for limited reusability, in the sense that one adhesive strip is used for each use of the shipping package 100. In other examples, multiple closures 112 may be used to increase reliability and/or security.

As shown in FIGS. 2A and 2B, the envelope 102 includes an outer layer 200 and an inner layer 202, which may be formed from a sheet or sheets of thin flexible material, such as polyethylene. An example laminate suitable for the envelope 102 is formed of layers of polyamide and polyethylene. The layers 200, 202 extend from the closed end 108 towards the open end 110 of the envelope 102. Near the open end 110, the inner layer 202 joins the outer layer 200. Hence, the envelope 102 is double walled except at the open end 110. The double wall may be extended closer to the open end 110 than depicted.

The space between the layers 200, 202 may be termed a thermal control space 204. The space bounded by the inner layer 202 and a relatively small portion of the outer layer 200 towards the open end 110, is a cavity or interior space 206 to hold a product 208 being shipped.

The shipping package 100 further includes phase-change material in the form of a mat 210. The mat 210 is a generally flat hollow body inside of which is phase-change material (PCM). The mat 210 may be a shell or bag of PCM. The mat 210 may include one or more interior cells that contain the phase-change material. The mat 210 may be composed of recyclable material, such as polyethylene, polyamide, non-woven film, or similar materials, in the form of a single layer of material or laminates of the same or different materials. Any suitable number and configuration of PCM mats 210 may be used.

Examples of suitable PCM include water-based gels (e.g., super-absorbent polymer or SAP, carboxymethyl cellulose or CMC, etc.); paraffins; hydrated salts or other binary eutectic mixtures; linear alcohols; organic compounds derived from animal fat or plant oil (sometimes referred to as biobased materials); materials based on palm oil, palm kernel oil, rapeseed oil, coconut oil, or soybean oil; and similar materials. A PCM may include a viscosity altering additive. A PCM may include an additive that makes it more flexible or pliable. The type and composition of PCM may be selected to achieve a desired cooling effect.

PCM mats 210 used in the same package 100 may contain different type and/or composition of PCM, so as to tune the performance of the package 100. Multiple mats 210 containing different PCM may be stacked together on one side of the interior space 206 to tune the performance of the package 100. In a given mat 210, different cells may have different PCMs. In various examples, multiple PCMs are provided, each to having a different temperature limit. For example, the shipping package 100 is to hold product between 2 degrees Celsius (C) and 30 C, PCMs rated for 5 C and 23 C may be used, with the 5 C PCM keeping the product from getting too cold and the 23 C PCM keeping the product from getting too hot. In another example, the shipping package 100 is to hold product between 2 C and 8 C, PCMs rated for 3 C and 7 C may be used, with the 3 C PCM keeping the product from getting too cold and the 7 C PCM keeping the product from getting too warm. In other examples, PCM is selected based on season. For example, a 5 C PCM may be used in winter and a 23 C PCM may be used in summer. In various examples, different PCMs may be located at opposite sides of the package 100. For example, one mat 210 may have PCM rated for 5 C and the opposing mat 210 may have PCM rated for 23 C. In still other examples, different cells in the same mat 210 may be filled with different PCMs.

In this example, a PCM mat 210 is positioned within the thermal control space 204 between the inner and outer layers 200, 202 of the envelope 102 at the large sides of the package 100. That is, in examples where the package 100 is generally rectangular, it has two large sides and at each of these sides, within the thermal control space 204, is positioned a PCM mat 210. As such, in this example, a pair of opposing PCM mats 210 sandwich the interior space 206 and thus the product 208 being shipped.

The shipping package 100 may further include a thermally insulative sheet 212 disposed within the thermal control space 204 and positioned at the outside of the PCM mats 210, that is, between the PCM mats 210 and the outer layer 200 of the envelope 102. In this example, the thermally insulative sheet 212 is folded to have two legs 214 extend along the PCM sheets 210 and to have a bend 216 that is positioned at the closed end 108 of the envelope 102. In this example, the thermally insulative sheet 212 is generally rectangular to match the overall shape of the envelope 102 and has about twice the planar area of each of the PCM mats 210, so as to match their combined area. In other examples, two separate thermally insulative sheets may be provided, one for each PCM mat 210.

The thermally insulative sheet 212 may be flexible and may have resiliency. The thermally insulative sheet 212 may be shaped and sized with respect to the envelope 102 so that its flexible resiliency gives shape to the envelope 102. For example, the normal shape of the thermally insulative sheet 212 may be flat, so that when the sheet 212 folded the bend 216 urges the legs 214 to move away from each other and push against the outer layer 200 of the envelope thereby expanding the envelope 102 to its extents to give it shape.

By the same principle, the flexible resiliency of the thermally insulative sheet 212 may urge the side edges 218 of the legs 214 closer together. That is, the envelope 102 may be shaped and sized to constrain the tendency for the thermally insulative sheet 212 to unfold, which may urge the side edges 218 closer together to reduce what might otherwise be a larger gap in insulation.

The thermally insulative sheet 212 may be made of cellulose, open-cell polyurethane, rubber (natural or synthetic), foam rubber, cotton, hemp, or similar materials.

Edges of the envelope 102 may be heat sealed, bonded with glue or adhesive, or otherwise joined. The PCM mats 210 and thermally insulative sheet 212 may be positioned with respect to a sheet of material being used to form the envelope 102 prior to joining edges of the material, so that the PCM mats 210 and thermally insulative sheet 212 are permanently enclosed within the thermal control space 204.

In operation, the shipping package 100 is placed in an environment, such as a refrigerator, cooler, or freezer, that causes exothermic phase change (e.g., freezing) of the PCM in the mats 210. Then, a product 208 to be shipped is inserted into the interior space 206 of the shipping package 100 and the closure 112 is closed. The shipping package 100 is then transported to the destination. During transport, the PCM in the mats 210 undergoes endothermic phase change (e.g., it melts) to regulate the temperature of the interior space 206 and product 208 contained therein. That is, environmental heat, which might otherwise warm the product 208, is instead absorbed by the PCM mats 210. Once the shipping package 100 arrives at its destination, the closure 112 may be opened and the product 208 removed. The shipping package 100 may then be reused provide that the closure 112 enables reuse.

For added protection, during operation, the shipping package may be inserted into an outer envelope, cardboard box, or plastic box or may be shrink-wrapped with plastic film. Such outer protection may be replaced each use or may be reusable. For example, an outer envelope or shrink-wrapping may be replaced each use, while a box may be reused.

FIG. 3 shows the shipping package 100 when open. As can be seen, in this example, the closure 112 includes a flap 300 of envelope material and an adhesive strip 302 attached to the flap 300. To close the package 100, the flap 300 may be folded over the open end 110 and the adhesive strip 302 adhered to the outside of the envelope 102 (see FIG. 1). To open the package 100, the flap 300 may be pulled to detach the adhesive strip 302 from the outside of the envelope 102.

FIG. 4 shows another example shipping package 400. Features and aspects of the package 400 may be the same as the package 100 with only differences discussed in detail here.

The shipping package 400 includes multiple closures to permit limited reuse. Each closure includes an adhesive strip 402, 404, 406 serially arranged on a flap 300 of envelope material. Each adhesive strip 402, 404, 406 functions in the same manner as the adhesive strip 302 discussed above with respect to FIG. 3. One adhesive strip 402, 404, 406 may be used each time the package 400 is used to ship a product. Accordingly, the number of reuses is the same as the number of adhesive strips 402, 404, 406, which in this example is three. In other examples, other numbers of adhesive strips 402, 404, 406 or other types of multiple closures may be used.

Lines of perforations 408, 410 may be provided between adhesive strips 402, 404, 406 to allow for easy opening of the package 400 and to facilitate reuse. For example, an adhesive strip 402 closest to the end of the flap 300 may be used to seal the package 100 for the first use. Then, to open the package 100, the line of perforations 408 adjacent the strip 402 may be broken, thereby separating the strip 402 from the flap 300 and allowing the flap 300 to open, while the strip 402 remains adhered to the outside of the envelope 102. Then, for a second use, the next adhesive strip 404, which is now closest to the end of the flap 300, is used in the same manner, with the next line of perforations 410 being used to open the package 400. This process may be repeated to consume all the adhesive strips 402, 404, 406 (or other closures) provided.

Limited reuse of the packages, as discussed herein, reduces waste compared to a single-use package, while also ensuring that the packages remain fit for purpose. The useable life of a package can be limited by the number of serial closures provided to the package. It is contemplated that various implementations of the packages discussed herein will have different amounts of closures depending on the specific applications intended. For example, packages for critical applications, such as medicine delivery, may be limited to one or two uses, while packages used for food delivery may be limited to four or five uses.

FIGS. 5A-5C show examples of PCM mats 500, 510, 520 useable with the packages discussed herein. A PCM mat 500, 510, 520 may include two layers of material that are bonded (e.g., heat sealed) at certain regions to form borders of cells and that are left unbonded at other regions to form the cells themselves to contain PCM.

As shown in FIG. 5A, a PCM mat 500 has a bonded perimeter 502 and three linear regions 504 of bonded material that extend (e.g., horizontally) between opposing points on the perimeter 502 to form four rectangular cells 506 that contain PCM. Owing to their lack of PCM, the bonded regions 504 may allow for the mat 500 to flex and therefore conform to the shape of the package.

As shown in FIG. 5B, a PCM mat 510 has a bonded perimeter 512, three linear regions 514 of bonded material that extend (e.g., horizontally) between opposing points on the perimeter 512, and one linear region 516 of bonded material that extends in a perpendicular direction (e.g., vertically) between opposing points on the perimeter 512. The bonded regions 514, 516 thus form a two-by-four grid of cells 516 that contain PCM. Owing to their lack of PCM, the bonded regions 514, 516 may allow for the mat 510 to flex in two dimensions and therefore conform to the shape of the package.

As shown in FIG. 5C, a PCM mat 520 has a bonded perimeter 522, three linear regions 524 of bonded material that extend (e.g., horizontally) between opposing points on the perimeter 522, and two linear regions 526 of bonded material that extend in a perpendicular direction (e.g., vertically) between opposing points on the perimeter 522. The bonded regions 524, 526 thus form a three-by-four grid of cells 526 that contain PCM. Again, owing to their lack of PCM, the bonded regions 524, 526 may allow for the mat 520 to flex in two dimensions and therefore conform to the shape of the package.

FIGS. 6A and 6B show another example shipping package 600. The shipping package 600 is similar to the other shipping packages discussed herein. Like reference numerals and terminology denote like components. Only differences will be described in detail and the description of the other shipping packages may be referenced for details not repeated here. FIG. 1 may be referenced for the general appearance of the shipping package 600.

The shipping package 600 includes an envelope 102 formed as discussed above.

Within the envelope 102, the shipping package 600 includes first and second PCM mats 602A, 602B within the thermal control space 204 on each large side of the interior space 206. Each side may also include one or multiple thermally insulative sheets 604 disposed within the thermal control space 204 between adjacent mats 602A, 602B. In this example, the insulative sheets 604 are generally flat and lack a bend. In other examples, a thermally insulative sheet 212 with a bend 216 (see FIG. 2A) may be used.

The mats 602A, 602B may be the same or similar as the mats 210 discussed above. Inner mats 602A that are closer to the interior space 206 and product 208 therein may have different PCM than outer mats 602B that are further from the interior space 206 and closer to the outside environment. Outer mats 602B may have PCM selected for the outside environment and inner mats 602A may have PCM selected for the thermal condition within the thermal control space 204, which is at least partially caused by the outer mats 602B, and for the desired thermal condition of the interior space 206.

In various examples, if the interior space 206 is to maintain a temperature between 2-8 degrees Celsius, two (or more) PCM mats, one with PCM configured for 3 degrees Celsius and the other with PCM configured for 7 degrees Celsius may be used. The inner mat 602A may have the 3-degree PCM and the outer mat may have the 7-degree PCM. The relative arrangement of mats may be reversed. For interior-space temperature service between 5-25 degrees Celsius, mats with 18-degree and 23-degree PCM may be used. For interior-space temperature service between 0-30 degrees Celsius, mats with 5-degree and 25-degree PCM may be used.

Mats 602A, 602B and insulative sheets 604 may be alternated like this up to any quantity practical.

The shipping package 600 may further include a thermally insulative sheet 606 positioned within the thermal control space 204 at the closed end 108 of the envelope 102. One or more PCM mats may be provided at this location as well. Alternating mats and insulative sheets may be provided at the end location up to any quantity practical.

The shipping package 600 may further include a thermally insulative sheet 608 positioned within the thermal control space 204 at the small sides 104, 106 of the envelope 102. One or more PCM mats may be provided at this location as well. Alternating mats and insulative sheets may be provided at each side location up to any quantity practical.

The thermally insulative sheets 606, 608 may also serve to hold the shape of the shipping envelope 600 and help maintain the size of the interior space 206 by, for example, resisting the collapse of the envelope.

FIG. 7 shows another alternating arrangement 700 of PCM mats 702 and thermally insulative sheets 704, which may be used with any of the shipping packages discussed herein. The arrangement 700 may be used at any of the large sides, small sides, ends, or other regions of a shipping package.

Each PCM mat 702 may be provided with PCM of desired properties, which may differ among the mats 702. Each insulative sheet 704 may be provided with desired properties, which may differ among the sheets 704. The arrangement 700 may include any practical number of mats 702 and sheets 704. The arrangement 700 may be tailored to provide a targeted thermal environment inside the shipping package based on expected conditions outside the shipping package.

As mentioned above, the mats selected for a package may have different PCM to tune performance. Similarly, different cells of a given mat may have different PCM to tune performance.

Further, a PCM mat may take the form of a sealed gel-filled bag with the gel being the PCM. The bag may be made from plastic film, such as a film of polyethylene, vinyl, nylon, or a laminate of any of two or more of these materials. A gel-filled bag may be less rigid than shell. However, in various implementations, increased flexibility may be tolerable or desirable.

As discussed above, a thermally insulative sheet may be flexible and resilient. In other examples, a thermally insulative sheet may be rigid.

In still other examples, as shown in FIG. 8, a thermally insulative sheet 800 may be made of rigid material that is segmented to provide local flexibility. Overall flexibility with rigid segments 802 may be achieved by any suitable number and placement of one or more strips (lines) 804 of flexible material between the rigid segments 802. A strip 804 allows for local bending or folding. A strip 804 may be realized by a thinned region of rigid material, scoring or a surface cut in rigid material, tape, an adhesive strip, and so on. In addition, while the example strips 804 shown extend in two perpendicular directions, in other examples any number of strips 804 (e.g., one, two, three, etc.) may be provided extending along any number of axes (e.g., one, two, three, etc.) which, when more than one axis is used, may be mutually arranged at various angles.

In various examples, a shipping package may include rigid thermally insulative sheets, flexible thermally insulative sheets, or a combination of such. Sheets, whether rigid, flexible, or a combination, may be stacked or bonded to form a thermally insulative laminate.

In various examples, two (or more) shipping packages of different sizes, with the same or different PCM and/or insulative sheets, may be used in conjunction. A product may be inserted into the smaller shipping package, and the smaller shipping package may be inserted into the larger shipping package. This assembly of shipping packages may be useful to provide additional customizability to the desired thermal protection of products.

PCM used for a given package may be selected based on the required performance of the package, which may depend on the season. The same applies to the thermally insulative sheet. The term “season” is used herein to denote different periods of time with different environmental conditions, not only the conventionally known seasons. For example, during the summer, products may be more susceptible to overheating when compared to other times. It may be useful to select different PCMs and/or insulation for service during different times of year. It may also be useful to keep a stockpile of packages on hand to readily ship product.

Accordingly, a shipping package as discussed herein may be provided with an indicator of the contained PCM and/or insulation. Such an indicator may indicate whether the package is intended for winter, spring, summer, or autumn service, for example. Example indicators include a sticker on the envelope, a color of the envelope, a text label on the envelope, and so on. PCM mats and thermally insulative sheets may also be given the same or similar indicator to facilitate maintenance and/or manufacture of packages. For example, envelopes, PCM mats, and/or thermally insulative sheets may be provided in sets of colors with the intention that like colored components are to be used together. For example, blue, grey, and white components may be used to indicate three seasons, and differently configured envelopes, PCM mats, and/or thermally insulative sheets may be provided in those colors.

A shipping package may use the techniques discussed above to increase efficiency, reduce complexity (and cost), promote reuse, and offer convenience to users.

It should be recognized that features and aspects of the various examples provided above can be combined into further examples that also fall within the scope of the present disclosure. In addition, the figures are not to scale and may have size and shape exaggerated for illustrative purposes.

Claims

1. A shipping package comprising: an envelope including a closed end and a closeable end, the envelope defining a thermal control space and an interior space that is separate from the thermal control space, wherein the internal space is configured to contain a product to be shipped;a first phase-change material mat positioned within the thermal control space and adjacent the interior space;a first thermally insulative sheet positioned within the thermal control space and adjacent the first phase-change material mat; anda second phase-change material mat positioned within the thermal control space and adjacent first thermally insulative sheet.

2. The shipping package of claim 1, wherein the first phase-change material mat, the first thermally insulative sheet, and the second phase-change material mat form an arrangement that is positioned on a first side of the interior space, the shipping package further comprising another such arrangement positioned on a second side of the interior space.

3. The shipping package of claim 1, further comprising a second thermally insulative sheet positioned within the thermal control space and adjacent the second phase-change material mat.

4. The shipping package of claim 1, further comprising an additional thermally insulative sheet positioned within the thermal control space and adjacent the interior space.

5. The shipping package of claim 4, wherein the additional thermally insulative sheet is positioned to maintain a size of the interior space.

6. The shipping package of claim 1, wherein the first thermally insulative sheet comprises rigid segments with a strip of flexible material therebetween.

7. The shipping package of claim 1, wherein one or more of the first and second phase-change material mats comprise a rigid shell containing phase-change material.

8. The shipping package of claim 1, wherein one or more of the first and second phase-change material mats comprise a flexible bag containing phase-change material.