| 摘要 |
A coextruded multi-layer opaque film which has been biaxially oriented by stretching in the longitudinal direction and transverse direction at selected temperatures and with selected stretch ratios, and a method for producing the film. The film has a base layer of polypropylene or a copolymer thereof, and fillers. Its density is 0.4 to 0.6 g/cm3, the amount of filler, based on the mixture of polypropylene and filler, is 16 to 30% by weight, and the particles of the filler employed have a mean size of 2 to 5 mu m. Because of its reduced tendency to recover after folding, the film is particularly suitable for packaging purposes. One or more surface layers can be applied on either or both sides of the base layer. |
