Patent ID: 8640430

Claim:
A package for holding a vacuum and to be filled with a particulate material, the package at least partially made of a packaging film, the packaging film surrounding the particulate material, the package including a rigid plate comprising first and second main surfaces separated by a thickness of the rigid plate and further including at least one opening fluidly connecting the first main surface to the second main surface, the rigid plate is placed against an inner surface of the packaging film; such that the first main surface of the rigid plate is provided with a flat portion and contacts the inner surface of the of the packaging film, the packaging film including an aperture at a location enclosed within the perimeter of the rigid plate, the first main surface of the rigid plate having a flat part at the location of the aperture, the aperture offset with respect to all the at least one opening, wherein the second main surface of the rigid plate, on the opposite side of the first main surface, is provided with at least one of (a) a groove in fluid communication with at least one opening and (b) a filter permeable to a fluid and substantially impervious to the particulate material, such that the rigid plate is permeable to the fluid to be evacuated and substantially impermeable to the product contained in the package and is resistant to clogging by the particulate material.