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Abstract: Concerns on food safety, and need for high quality and extended shelf-life of packaged foods have promoted the development of antibacterial barrier packaging materials. Few articles have been available dealing with the barrier or antimicrobial properties of zinc oxide thin films deposited at low temperature with atomic layer deposition (ALD) onto commercial polymer films typically used for packaging purposes. The purpose of this paper was to study the properties of ZnO thin films compared to those of aluminum oxide. It was also possible to deposit ZnO thin films onto oriented polylactic acid and polypropylene films at relatively low temperatures using ozone instead of water as an oxidizing precursor for diethylzinc. Replacing water with ozone changed both the structure and the chemical composition of films deposited on silicon wafers. ZnO films deposited with ozone contained large grains covered and separated probably by a more amorphous and uniform layer. These thin films were also assumed to contain zinc salts of carboxylic acids. The barrier properties of a 25nm ZnO thin film deposited with ozone at 100°C were quite close to those obtained earlier with ALD Al2O3 of similar apparent thickness on similar polymer films. ZnO thin films deposited at low temperature indicated migration of antibacterial agent, while direct contact between ZnO and Al2O3 thin films and bacteria promoted antibacterial activity. [Copyright &y& Elsevier]

Abstract: Thin atomic layer deposited (ALD) Al2O3 coatings are efficient barriers against gases and vapors. Al2O3 coatings are, however, brittle and straining them generates defects that impair barrier properties. Flexibility of ALD-grown Al2O3 coatings on biopolymer substrates can be improved by separating thinner Al2O3 layers with inorganic–organic alucone layers. The number and size of defects were smaller for these nanolaminates compared to the thick Al2O3 films after straining, and hence straining deteriorated the oxygen barrier properties less when applied to the laminates than when applied to the Al2O3 coatings. [Copyright &y& Elsevier]

Abstract: Thin (25nm) and highly uniform Al2O3 coatings have been deposited at relatively low temperature of 80 and 100°C onto various bio-based polymeric materials employing the atomic layer deposition (ALD) technique. The work demonstrates that the ALD-grown Al2O3 coating significantly enhances the oxygen and water vapor barrier performance of these materials. Promising barrier properties were revealed for polylactide-coated board, hemicellulose-coated board as well as various biopolymer (polylactide, pectin and nano-fibrillated cellulose) films. [Copyright &y& Elsevier]

Abstract: The effect of corona pre-treatment on the performance of Al2O3 and SiO2 gas barrier layers applied by atomic layer deposition onto polymer-coated paperboards was studied. Both polyethylene and polylactide coated paperboards were corona treated prior to ALD. Corona treatment increased surface energies of the paperboard substrates, and this effect was still observed after several days. Al2O3 and SiO2 films were grown on top of the polymer coatings at temperature of 100°C using the atomic layer deposition (ALD) technique. For SiO2 depositions a new precursor, bis(diethylamido) silane, was used. The positive effect of the corona pre-treatment on the barrier properties of the polymer-coated paperboards with the ALD-grown layers was more significant with polyethylene coated paperboard and with thin deposited layers (shorter ALD process). SiO2 performed similarly to Al2O3 with the PE coated board when it comes to the oxygen barrier, while the performance of SiO2 with the biopolymer-coated board was more moderate. The effect of corona pre-treatment was negligible or even negative with the biopolymer-coated board. The ALD film growth and the effect of corona treatment on different substrates require further investigation. [Copyright &y& Elsevier]

Abstract: Thin (30–40nm) and highly uniform Al2O3 coatings have been deposited at relatively low temperature of 100°C onto various polymeric materials employing the atomic layer deposition (ALD) technique, both batch and roll-to-roll (R2R) mode. The applications for ALD have long been limited those feasible for batch processing. The work demonstrates that R2R ALD can deposit thin films with properties that are comparable to the film properties fabricated by in batch. This accelerates considerably the commercialization of many products, such as flexible, printed electronics, organic light-emitting diode lighting, third generation thin film photovoltaic devices, high energy density thin film batteries, smart textiles, organic sensors, organic/recyclable packaging materials, and flexible displays, to name a few. [Copyright &y& Elsevier]