| abstract |
A process for the production of a wall for a package including producing a preform of the wall and stretching the preform of the wall where the preform includes a layer containing a polymer and having oxygen-scavenging properties. The preform and the stretching ratios applied are chosen (i) so that the time (tI) which the permeance of the wall for oxygen would take to rise to 1/5 of the value it would have in the absence of oxygen scavenging would be at least 10 days and (ii) if the preform were stretched at that time (tI) after the preform were produced, the time (tD) which the permeance of the wall for oxygen would take to rise 1/5 of the value it would have in the absence of scavenging would be at least 1/4 of the time (tI). The time between completion of step (A) and the commencement of step (B) is at least 10 days. |