152 and eha 019 products of mobil linear low density polyethylene component should have density from 0 916 to 0 925 g cm 3 preferably from 0 918 to 0 923 g cm 3 more preferably 0 918 to 0 921 g cm 3 and melt index from 0 50 to 1 6 dg min preferably from 0 5 to 1 2 dg min more preferably 0 6 to 1 1 dg min examples of suitable lldpe resins are dowlex 2021 dowlex 2045 dowlex 2070 dowlex 2073 and dowlex 2101 products of dow chemical canada inc of these dowlex 2021 is preferred further examples are l 2007 f l 2001 f and l 2002 f products of eastman kodak a pigment is added to the resin composition of the invention to reduce the light transmission of the film reducing the amount of light penetrating into the tube reduces the spoilage of the product stored therein by eliminating or limiting photochemical processes initiated by the light making the tube opaque also provides a protection against birds which frequently puncture transparent tubes when attracted by their content pigment of any colour can be used if compatible with the resin composition in the amount necessary to reduce the light transmission of the film to below 45 light transmission in the range of from 25 to 35 is preferred reducing the light transmission even further increases the cost of the product without increasing substantially the light protective capacity of the film examples of suitable pigments include titanium dioxide carbon black iron oxide ultramarine blue phthalocyanine green and quinacridone red of these titanium dioxide is preferred in a monolayer film using a white pigment increases the reflectivity of the film and reduces the light.