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, comprising:
a means for changing phase that changes from a liquid to a solid and back to a liquid at a desired phase change temperature;
a shape-stable means for absorbing the means for changing phase in its liquid form, so as to absorbed into the means for absorbing at greater than about 91 percent by volume of the means for absorbing, and at greater than about 98 percent by weight of the combined means for changing phase and means for absorbing; and
a protective covering encasing the means for changing phase and means for absorbing.
2. The device of claim 1 , wherein the means for absorbing is a foam selected from the group consisting of phenolic foam, phenol-aldehyde resol resin, phenol derivatives, polyurethanes, polystyrenes, and mixtures and combinations thereof.
3. The device of claim 2 , wherein foam has micropores and macropores and at least a portion of the micropores are in a lattice within a macropore.
4. The device of claim 2 , wherein the foam is characterized as having a density between about 0.00069 to 0.00084 pounds per cubic inch.
5. The device of claim 1 wherein the means for changing phase is selected from the group consisting of salts, hydrated salts, fatty acids, paraffins, and solutions, derivatives and mixtures thereof.
6. The device of claim 1 , wherein the means for changing phase is a salt solution comprising sodium chloride, the salt composition being between about 20 to 23 weight percent of the solution.
7. The device of claim 1 wherein the shape-stable means for absorbing is characterized as having macropores of a diameter between about 100 to 400 microns, and micropores of a diameter between about 0.5 to 100 microns.
8. The device of claim 1 , wherein temperature is controlled between about −19 to −21 degrees Celsius.
9. 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.
10. The device of claim 1 , wherein the protective covering comprises a 60 g Biax Nylon layer, an ink layer having a thickness of about 0.03 mils, an adhesive layer having a thickness of about 0.07 mils, and a white LLDPE layer having a thickness of about 2.5 mils.
11. The device of claim 2 , wherein the foam is in the form of a workpiece wherein the average thickness to surface area ratio ranges from about 1% to about 8%.