Automatically ventable sealed food package for use in microwave ovens
AssigneeAmerican Can Company
InventorRichard P. Mitchell
Life of this patent
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Abstract
A refrigerated food is packaged in a paperboard tray covered by a plastic film bonded to upper edges of the tray sidewalls in provision of a barrier against contamination of the food. The film and the tray are transparent to microwave energy for heating the food, and automatic venting of the covered tray, while heating, is afforded by a relatively small strip of electrically conductive material on the film and absorptive of microwave energy in an amount sufficient to heat the same and melt a vent opening in the film.
Claims12
A refrigerated food package capable of being heated in a microwave oven, said package comprising dielectric receptacle means and dielectric cover means hermetically sealed thereover to accommodate heating of food contained therein by microwave energy, and means for venting said package automatically in response to its subjection to microwave energy, said means for venting including a strip of electrically conductive material on said cover means so shaped and dimmensioned as to be heated by said microwave energy, upon heating said package, in an amount effective to produce a venting perforation in said cover means wherein said cover means is of a meltable material and the heat content of said strip of electrically conductive material is effective to raise the temperature of the underlying portion of the cover means to melt the latter in production of said venting.
Dependencies are inferred from the claim text.