Influence of substrate contamination, web handling, and pretreatments on the barrier performance of aluminum oxide atomic layer-deposited BOPP film

This study shows the sensitivity of the performance of a 30 nm Al2O3 barrier layer deposited by atomic layer deposition (ALD) on biaxially oriented polypropylene (BOPP) film to material processing. The most detrimental effects were caused by the contact between the rollers and the deposited layer during web handling and the surface contamination of the substrate prior to the deposition process. The shipment of the material as sheets and the atmospheric corona treatment of the coated surface had also a minor effect on the barrier performance. The results obtained show the importance of carrying out protective actions during both pre- and post-processing of the material in order to maintain the barrier performance of an ALD-Al2O3 layer.