| abstract |
The present invention relates to a cover (4) of a product package to be heat-sealed on the mouth of a product package and extractable therefrom when opening, and a method for manufacturing same. The cover is appropriate particularly for dosage packages of foodstuffs, such as milk, yoghurt, juices and fruit syrups, desserts, etc., or for drug packages. The cover is made of paper (5) which is provided with polymer coating layers (6) on the undersurface, comprising a formally polymer binding agent layer and a heat-sealable polymer layer of an oxygen-tight, non-puncturable support layer, enabling extraction of the cover when opening the package. The essential feature in the invention lies therein that the support layer includes, as described above, a polymer component of high degree of crystallization and amorphous polymer component, wherewith the curling of the cover is prevented. Production of the cover (4) is accomplished with simultaneous extrusion of the polymer layers (6). |