PACKAGING MATERIAL

摘要

The present invention provides a wall for a package comprising:- (a) an outer set of one or more layers (1-4) and (b) an inner set of one or more layers (5-6) which layer or the outermost of which layers (5) comprises a composition comprising a polymer and having oxygen-scavenging properties,- wherein - (i) the outer set of layers would have, if separate from the inner set and in the absence of any oxygen-scavenging properties in any of the layers or the layer constituting the set, a permeance, for oxygen, of not more than 1.5 cm<3>/(m<2> atm day); (ii) the inner set of layers would have, if separate from the outer set and in the absence of oxygen-scavenging properties in any of the layers or the layer constituting the set, a permeance, for oxygen, of at least 2.0 cm<3>/(m<2> atm day); and (iii) the inner set of layers would have, if separate from the outer set, a permeance, for oxygen, less than the permeance specified in (ii) by at least 1.0 cm<3>/(m<2> atm day) by virtue of oxygen-scavenging in at least the layer specified in (b). In a preferred combination one of the outer layers (3) is of metal and the composition in the outermost of the inner layers (5) scavenges oxygen through the metal-catalysed oxidation of an oxidisable organic component thereof. The wall is suitable for packaging uses, with the inner set of layers disposed towards the product, where headspace scavenging is especially desired.