SEALED INNER PACKAGE PROVIDED WITH AN EXHAUST HOLE REGULATED BY AN EXHAUST VALVE, MULTILAYER SHEET OF PACKING MATERIAL, AND METHOD OF PRODUCING A MULTILAYER SHEET OF PACKING MATERIAL

摘要

Package (1) having: a group (4) of articles; a sealed inner package (3), which encloses the group (4) of articles, has an article extraction opening (5) and is formed from a sheet (14) of heat-sealable packing material which is folded about the group (4) of articles and stabilized by heat-sealing; at least one exhaust hole (18), which is formed through a wall of the sealed inner package (3) to exhaust part of the air from, and depressurize, the sealed inner package (3) itself; and an exhaust valve (19) which is superimposed over the exhaust hole (18) and has at least one valve element (20), which is movable between a closed position in which it seals the exhaust hole (18) and isolates the exhaust hole (18) from the outside atmosphere and an open position in which the exhaust hole (18) communicates freely with the outside atmosphere.