Heat-sealable polypropylene film.

摘要

The invention is concerned with a heat-sealable polypropylene film which has improved absorption properties for ultra-violet light and which, when viewed, is opaque white on one surface and pearlescent on the other surface. The film comprises a base polypropylene film which incorporates 1% to 30% by weight of a particulate material (size 0.2 to 25 microns), such as calcium carbonate, and which has been stretched to form voids substantially at the location of each particle. A layer of a transparent heat-sealable polymeric composition is applied to each side of the base film and in one layer there is dispersed 2.5% to 35% by weight of finely divided titanium dioxide. The sealing properties of the layer containing the titanium dioxide are substantially unchanged by the addition.