PACKAGING MATERIAL COMPRISING INDICATOR RESPONDING TO AN EXTERNAL STIMULUS

摘要

A packaging material for use in a package having contents including a fooditem, the packaging material includes a layerincluding an additive transformable from a first state to a second state inresponse to an external stimulus and a barrier layer positionablebetween said layer and the contents of the package. The barrier layerrestricts diffusion of said additive to the contents.