PRODUCT PACKAGING CONTAINERS OBTAINED BY FOLDING A MULTILAYER SEMI-RIGID SHEET MATERIAL HAVING HIGH THERMAL RESISTANCE

摘要

The invention relates to a process for obtaining a multilayer material [10] consisting of semi-rigid sheets with good hold, resistance to temperatures in excess of 124° C. and low gas permeability which can be folded and intended for the manufacture by folding of containers [20] constituting an internal space for the packaging of thermally treated products, such a container [20] a process for obtaining such a multilayer material; [10] and a process for manufacturing the product packaging. The multilayer material [10] is comprised of at least one external layer [11] of polymer material and one internal layer [12] of polymer material between which the multilayer material [10] has low permeability to gases such that there is a positive humidity sensitivity gradient [14, 13] of the gas permeability from the inside towards the outside, this gradient allowing drying of the multilayer material [10] by evaporation towards the outside during stabilisation of the multilayer material [10] following thermal processing of the packaged products.