Thermally insulated containers
A thermally insulated container includes a base having a bottom wall and sidewalls, and a lid. A liquid-impermeable and moisture-resistant film overlays the outer surface of the base and sidewalls and can extend inside of the base. The film can be plastic shrink wrap film. The sidewalls of the base can be tapered to allow the containers to be nested in a stacked arrangement.
Latest SCA Packaging North America, Inc. Patents:
The invention is directed to thermally insulated containers and to methods of making the containers.
Thermally insulated containers for containing cold and frozen substances, such as medical products, food, and beverages, are typically made of molded plastic materials that have low thermal conductivity so that such substances can be kept cold, frozen or warm for extended periods of time.
An exemplary transport container described in WO 02/085749 A1 includes a rigid liner, a plurality of layers of flexible insulating material around the liner, an envelope containing the layers and shrunk against the layers, and a cavity within the rigid liner to receive a product to be transported in the transport container.
An object is to provide alternative insulated containers, as well as methods of making the containers.
SUMMARYAn embodiment of an insulated container system, comprising a rigid foam container having a bottom wall including an outer surface, a plurality of sidewalls each including an outer surface and an inner surface; and a film which overlays the outer surface of the bottom wall and of each of the sidewalls and which forms an outer surface of the base; and a lid configured to cover an open end of the rigid foam container opposite the bottom wall.
Another embodiment of the thermally insulated container is provided, which comprises a base including a bottom wall, a plurality of sidewalls and a liquid-impermeable and moisture-resistant film. The bottom wall includes an outer surface. Each of the sidewalls is tapered and includes an outer surface and an inner surface. The film overlays at least the outer surface of the bottom wall and the outer surface of each of the sidewalls and forms the outer surface of the base. The container comprises an optional lid configured to cover an open end of the base.
Another embodiment of a rigid, thermally insulated container system, comprising a rigid styrofoam container having a bottom wall and a plurality of sidewalls integrally connected to the bottom wall; a liquid-impermeable and moisture-resistant film overlaying an outer surface of the bottom wall and each of the sidewalls and providing an outer surface of the base; and indicia on the film at the outer surface of at least one of the sidewalls; and a lid configured to cover an open end of the base opposite the bottom wall.
Methods of making the thermally insulated containers are also provided.
DRAWINGS
The base 12 and lid 14 are composed of a material that has low thermal conductivity so that the container 10 is thermally insulated. Accordingly, the container 10 can be used to store and transport cold, frozen, or heated substances. For example, the container 10 can be used to store various hot or cold liquids and solids, such as hot or cold beverages, food and medical products. An exemplary suitable material for making the base 12 and lid 14 is expanded polystyrene (EPS). EPS is a lightweight, rigid foam plastic having low thermal conductivity. Another suitable material for making the base 12 and lid 14 is polyethylene.
However, although EPS, for example, can provide desirable thermal insulation properties, it has been determined that liquids, such as water from melting ice, can eventually permeate through such materials and cause leakage from the container to occur. To reduce or completely eliminate such leakage of liquids, the container 10 may include a film 28, preferably liquid-impermeable and moisture-resistant film, applied to overlay portions of the container, preferably the outer surface 24 of the bottom wall 18 and at least the outer surface 20 of each of the sidewalls 16. The film 28 forms the outer surface of the base 12. The film 28 is preferably a plastic shrink-wrap film applied on the base 12 to form a sealed fit to at least the outer surface 24 of the bottom wall 18 and the outer surface 20 of the respective sidewalls 14.
The film 28 can be composed of any suitable material that is liquid-impermeable and moisture-resistant and can be applied to the base 12 by a shrink fitting process. The film 28 preferably is durable and sufficiently thick to resist tearing and other wear caused by contact with other surfaces or objects. For some retail and medical applications of the container 10, the liquid-impermeable and moisture-resistant material preferably is stain resistant. Exemplary materials for the film 28 that provide suitable properties for use in the container 10 are polyethylene and polyethylene blends.
The film 28 can be applied on the base 12 by any suitable heat-shrink process. For example, a plastic shrink bag having an open end can be pulled over the base 12 and then placed in a heated atmosphere, such as in a heat tunnel or the like, to heat the bag to a sufficiently high temperature to shrink the bag tightly around the bottom wall 18 and sidewalls 16 to provide a liquid-impermeable and moisture-resistant barrier on the outside of the base 12.
The process conditions used for the heat shrink process can be selected based on various factors, including the container material, the container wall thickness, the shrink wrap film composition, and the length of the heated region, preferably a heat tunnel, through which the container and shrink wrap film are conveyed. For example, a container composed of EPS and a polyethylene film can typically be heated at a temperature of from about 150° C. to about 260° C. The dwell time, which is the amount of time that the container and film are heated in the heated region, can typically be from about 15 seconds to about 60 seconds.
As shown in
In the embodiment of the container 10 shown in
The foregoing has described principles, preferred embodiments and modes of operation of the invention. However, the invention should not be construed as being limited to the particular embodiments discussed. Thus, the above-described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by workers skilled in the art without departing from the scope of the invention as defined by the following claims.
Claims
1. An insulated container system, comprising:
- a rigid foam container having a bottom wall including an outer surface, a plurality of sidewalls each including an outer surface and an inner surface; and
- a film which overlays the outer surface of the bottom wall and of each of the sidewalls and which forms an outer surface of the base; and
- a lid configured to cover an open end of the rigid foam container opposite the bottom wall.
2. The container system of claim 1, wherein the film is disposed between the lid and an upper surface of each of the sidewalls when the lid closes the open end.
3. The container of claim 1, wherein the sidewalls, bottom wall and lid are composed of a rigid, thermally insulated material.
4. The container of claim 1, wherein the sidewalls, bottom wall and lid are composed of expanded polystyrene.
5. The container of claim 1, wherein the sidewalls are each tapered.
6. The container of claim 1, wherein the sidewalls are each perpendicular to the bottom wall.
7. The container of claim 1, wherein the outer surfaces of the sidewalls are contoured.
8. The container of claim 1, wherein the film is a liquid impermeable and moisture-resistant film.
9. The container of claim 8, wherein the film is a plastic shrink-wrap film.
10. The container of claim 1, wherein the film includes indicia at the outer surface of each of the sidewalls.
11. A rigid, thermally insulated container, comprising:
- a base comprising: a bottom wall including an outer surface; a plurality of tapered sidewalls each including an outer surface and an inner surface; and a film overlaying at least the outer surface of the bottom wall and of each of the sidewalls and forming an outer surface of the base; and
- a lid configured to cover an open end of the base opposite the bottom wall.
12. The container of claim 11, wherein the film is a liquid-impermeable and moisture-resistant film.
13. The container of claim 11, wherein the film is disposed between the lid and an upper surface of each of the sidewalls when the lid closes the open end.
14. The container of claim 11, wherein the film overlays an upper surface of each of the sidewalls.
15. The container of claim 11, wherein the sidewalls, bottom wall and lid are composed of a rigid, thermally insulated material.
16. The container of claim 11, wherein the sidewalls, bottom wall and lid are composed of a rigid, foamed plastic material.
17. The container of claim 12, wherein the film is a plastic shrink-wrap film.
18. A rigid, thermally insulated container system, comprising:
- a rigid styrofoam container having a bottom wall and a plurality of sidewalls integrally connected to the bottom wall; a liquid-impermeable and moisture-resistant film overlaying an outer surface of the bottom wall and each of the sidewalls and providing an outer surface of the base; and indicia on the film at the outer surface of at least one of the sidewalls; and
- a lid configured to cover an open end of the base opposite the bottom wall.
19. A method of making a thermally insulated container, comprising:
- providing a container comprising: a bottom wall including an outer surface and an inner surface; and a plurality of sidewalls each including an outer surface and an inner surface; and
- applying a film on the container such that the film (i) overlays the outer surface of the bottom wall, (ii) overlays the outer surface and inner surface of each of the sidewalls, and (iii) forms an outer surface of the base.
20. The method of claim 19, wherein the film is a liquid impermeable and moisture-resistant film.
21. The method of claim 20, wherein the film is a plastic shrink-wrap film, and the applying comprises heating the film so as to shrink the film onto the container.
22. The method of claim 21, further comprising printing indicia on the film prior to heating the film.
23. The method of claim 19, wherein the sidewalls of the container are tapered.
Type: Application
Filed: Nov 1, 2004
Publication Date: May 4, 2006
Applicant: SCA Packaging North America, Inc. (Eddystone, PA)
Inventors: Kevin Grogan (Elmhurst, IL), Kenneth Harris (Deerfield, IL), John Trease (Elkhart, IN), Doug Stein (Highland, IL)
Application Number: 10/976,908
International Classification: B65D 3/22 (20060101);