Patent ID: 7637283

Claim:
A pressure relief valve for use on a packaging surface of packaging containers comprising: a stiff support body mountable to a package surface defining an inner aperture wherein the stiff support body has a stiffness of between around 300 gram-centimeters and around 800 gram-centimeters; a flexible film having a top and bottom surface mounted to said stiff support body and movable between an open and closed position; a rail mounted above said flexible film holding said flexible film to said stiff support body and permitting the flexible film to move between an open and closed position; wherein: in said open position, said film is located above said aperture; in said closed position, said film covers said aperture; and wherein the stiff support body does not conform with any curvature of the packaging surface such that the flexible film may move between said open and closed position regardless of the curvature of the packaging surface.