Patent ID: 9585515
Date: 2017-03-07
CPC Classifications: A47J,B32B,B65D,Y10T

Claim:
1. A microwavable food package, comprising: an expandable first base film and an expandable second base film that are bonded or laminated together, wherein the expandable first and second base films are configured to form the microwavable food package having an inner surface which defines an interior space for storing and cooking food, and an outer surface which is in contact with an exterior environment, and wherein the interior space and the first and second base films expand in response to pressure buildup created by a microwave cooking process; and a plurality of laser-formed microperforations that have a diameter of 1 to 500 microns, that extend from the interior space through the first base film and the second base film so as to be open prior to and during the microwave cooking process, that are arranged at a density of 1 to 50 microperforations per cm a respiration system including at least some of the plurality of microperforations that are open prior to the microwave cooking process and that have a diameter configured to allow the transmission of gases between the interior space and the exterior environment so that the interior space has an internal atmosphere including 2-18% O a venting system including at least some of the microperforations of the respiration system that expand during the microwave cooking process to a larger diameter, wherein the size, density, location and expansion of the microperforations of the venting system allow the interior space to first expand during the microwave cooking process without bursting and then controllably release excess pressure build-up during the microwave cooking process to provide a steam cooking function.