Creation of a microrelief by thermally stimulated shrinkage of metal-coated polypropylene films

A study was made of the conditions of producing micron-sized reliefs by thermally stimulated shrinkage of metallized commercial biaxially oriented polypropylene films. It was shown that, in annealing within a temperature range close to the polypropylene melting point, the film shrinks in two directions to form folded structures on the surface. The folds are about 2–8 μm in size. The shrinkage and the relief depth depend on the annealing temperature. The relief remains on the film surface after the removal of the aluminum layer.