Abstract: The improved packaging material having oxygen barrier quality has a thin layer of inorganic substance formed on a layer of resin composition having oxygen barrier quality that comprises at least a thermoplastic resin and an oxidation catalyst. The packaging material is inexpensive, can be processed efficiently and it yet develops high oxygen barrier quality right after processing and maintains it for a prolonged period of time.

Abstract: The improved resin composition including a polyolefin, a transition metal containing oxidation catalyst and 0-500 ppm of a radical inhibitor can be used to fabricate a sheet and a container that have good oxygen barrier quality on its own without being combined with expensive other resins that have oxygen barrier quality.

Abstract: A process for sterilizing a material contained in a sealed microwave permeable package which is stored, under normal pressure, in a heat resisting and pressure resisting support during microwave irradiation. The heat resisting and pressure resisting support is conveyed on a conveyor belt into a plurality of microwave heating chambers in which local heating waveguides are provided in close proximity to the heat resisting and pressure resisting support and overall heating waveguides are provided at the wall of the microwave heating chambers. The heat resisting and pressure resisting support with the package is alternately irradiated by the local heating waveguides and the overally heating waveguides during conveyance through the microwave heating chambers so as to effect the substantially uniform heating of the material in the package. To regulate the degree to which the peripheral portions of the package are heated, the distance between the local heating waveguides and the package can be adjusted.