Thermally-controlled packaging device and method of making
View Patent ↗A phase change device for controlling temperature within a confined environment, comprising a foam material, a phase change material, the phase change material being absorbed into the foam, and a protective covering encasing the foam material/phase change material. A method for making a phase change device for controlling temperature within a confined environment, comprising providing a phase change material, providing a foam material, absorbing the phase change material into the foam material, and sealing the foam material/phase change material within a protective covering.
1. A phase change device for controlling temperature within an environment, the device comprising:
an open-celled foam having macropores and micropores defined therein;
a phase change material selected from the group consisting of salts, hydrated salts, fatty acids, paraffins, and solutions, derivatives and mixtures thereof;
wherein the phase change material is absorbed within the open-celled foam in an amount of about 88 percent to 96 percent by volume of the open-celled foam to make a filled foam, and the filled foam is characterized by the absence of description of the phase change material; and
a protective covering encasing the filled foam.
2. The device of claim 1 wherein the volume defined between the filled foam and the covering is characterized by the absence of air.
3. The device of claim 1 wherein the protective covering clings to the filled foam and confines the phase change material against the surface of the foam.
4. The device of claim 1 wherein the protective covering comprises a nylon layer, an adhesive layer, a white polyethylene layer, and an LLDPE sealant layer.
5. The device of claim 1 , wherein the protective covering comprises:
a first film having sealing edges extending therefrom; and
a second film mating with the sealing edges, wherein any air within the volume defined by the bottom film and cover film is evacuated to cause the first film and second film to cling to portions of the surface of the filled foam.
6. The device of claim 1 , wherein the protective covering comprises:
a bottom film formed into a shape having a base, sides extending perpendicular from the base and sealing edges extending generally perpendicularly from the sides; and
a cover film mating with the sealing edges, wherein any air within the volume defined by the bottom film and cover film is evacuated to cause the bottom film and cover film to cling to portions of the surface of the filled foam.
7. The device of claim 1 , wherein the filled foam has a ratio of average thickness to top-surface area ratio of between approximately 1% and 8%.
8. The device of claim 1 , wherein the phase change material is absorbed within the open-celled foam in an amount of about 92 percent to 99 percent by weight of the open-celled foam.
9. The device of claim 1 wherein the open celled foam comprises a phenol-aldehyde polymer, a polyurethane, polystyrene, or a mixture or combination thereof.
10. The device of claim 1 wherein at least a portion of the micropores are defined within a macropore.
11. The device of claim 1 wherein the macropores have a diameter of between about 100 to 400 microns, and micropores have a diameter of between about 0.5 to 100 microns.
12. The device of claim 1 wherein the phase change material is a sodium chloride solution, wherein the sodium chloride is present at about 20 to 23 weight percent of the solution.