Food package comprised of polymer with thermally responsive permeability
Patent 5254354 Issued on October 19, 1993. Estimated Expiration Date: May 18, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
426/106, PACKAGED OR WRAPPED PRODUCT426/415, Utilizing specified wrapping material426/418, Storing solid material under controlled condition426/419, Natural plant material428/35.4Contains vapor or gas barrier, polymer derived from vinyl chloride or vinylidene chloride, or polymer containing a vinyl alcohol unit
Food may be packaged and preserved for extended periods using intelligent polymers formed into food containers which have specific and variable gas permeabilities. The polymers used in forming the food packages are intelligent in that they have permeabilities which may be radically and reversibly changed by relatively small changes in temperature. By using different types and formulations of polymers and various temperatures, it is possible to create an environment within the food package which adjusts to the respiration of the food so as to best preserve the color, quality and/or shelf life of the food. The polymers are side-chain crystallizable polymers designed and formulated so as to provide a material which is substantially impermeable to a gas such as oxygen, carbon dioxide or water vapor at a temperature below a given phase transition point and permeable to the same gas at a temperature above that point.
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May 18, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
