| 摘要 |
A hermetically closed package enclosing a product comprises a wall formed of a packaging material including a first polymer film (7) and a second polymer film (10) being co-extensive with the packaging material, the first polymer film (7) is laminated to the second polymer film (10) by means of an adhesive layer (16). One of the polymer films is provided in a limited region thereof with a layer of a material generating heat when subjected to microwave radiation, i.e. a heat-generating layer (5) having susceptor effect. The heat-generating effect, i.e. the susceptor effect, of the heat-generating layer (5) is selected so as to melt, decompose, soften or weaken the first polymer film (7) and/or the second polymer film (10) in the limited region as seen transversely of the packaging material to such a degree that an opening is formed in the limited region. |
