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The purpose of this study was to evaluate the feasibility of using highly filled powders as electrostatically applied paper coatings. Powders prepared by two different methods were suitable for electrostatic deposition and they attached to the paper surface with a grounded backing. Pressing at elevated temperatures turned out to be a crucial process step for improving the adhesive and cohesive strengths of the powder coating layer on paper. Limited mechanical interlocking with the base paper and an uneven pressure profile were factors impairing the surface strength of the coated paper. On the other hand, factors such as higher polymer content, higher pressing temperature, pre-heating the paper prior to coating, and increasing the number of hot roll nips increased adhesion between the coating and the base paper. Powder coatings as such had uneven thickness, and they displayed a relatively broad pore size distribution. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the feasibility of using highly filled powders with 100 parts per weight of calcium carbonate and 10 parts per weight of polymer, acting as binder, as electrostatically applied paper coatings. Such powders prepared by different methods were evaluated as being suitable for electrostatic coating. Powders compacted at elevated temperatures demonstrated cohesion superior to that of calcium carbonate, and at best similar to that of aqueous coatings. Cohesion, porosity and thus absorption properties of compacted powders were affected by the powder preparation method, compaction process, and powder composition. Powders containing semicrystalline polymer turned out to be the most interesting for further testing. [ABSTRACT FROM AUTHOR]

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: Atomic and molecular layer deposition (ALD and MLD, respectively) techniques are based on repeated cycles of gas–solid surface reactions. A partial monolayer of atoms or molecules is deposited to the surface during a single deposition cycle, enabling tailored film composition in principle down to molecular resolution on ideal surfaces. Typically ALD/MLD has been used for applications where uniform and pinhole free thin film is a necessity even on 3D surfaces. However, thin – even non-uniform – atomic and molecular deposited layers can also be used to tailor the surface characteristics of different non-ideal substrates. For example, print quality of inkjet printing on polymer films and penetration of water into porous nonwovens can be adjusted with low-temperature deposited metal oxide. In addition, adhesion of extrusion coated biopolymer to inorganic oxides can be improved with a hybrid layer based on lactic acid. [Copyright &y& Elsevier]

Abstract: The effects of thin film nucleation and initial growth on roughness, chemistry and thermomechanical properties of polymer film surfaces were studied. Al2O3 was deposited onto commercial biaxially oriented polypropylene and polylactic acid films at 80°C by using atomic layer deposition technique. Both substrates, especially the more hydrophobic polypropylene, showed initial growth through Al2O3 clusters. There was a faster deposition of Al2O3 on polylactic acid film than on polypropylene at the early stages of the Al2O3 deposition. There were also indications of chemical interactions between polylactic acid and trimethyl aluminum used as a precursor for Al2O3. Changes in the thermo-mechanical properties of the polymer surfaces with Al2O3 also evidenced the differences between the substrate polymer films. The near surface interphase formed in polylactic acid probably contributed to the strong increase and scattering in the softening temperature during the early thin film growth. [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: Commercial polylactide (PLA) films are coated with a thin (20nm) non-toxic polyelectrolyte multilayer (PEM) film made from sodium alginate and chitosan and additionally with a 25-nm thick atomic layer deposited (ALD) Al2O3 layer. The double-coating of PEM+Al2O3 is found to significantly enhance the water vapor barrier properties of the PLA film. The improvement is essentially larger compared with the case the PLA film being just coated with an ALD-grown Al2O3 layer. The enhanced water vapor barrier characteristics of the PEM+Al2O3 double-coated PLA films are attributed to the increased hydrophobicity of the surface of these films. [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: Atomic layer deposition (ALD), electron beam evaporation, magnetron sputtering and a sol–gel method were used to deposit thin aluminum oxide coatings onto two different fiber-based packaging materials of commercial board grades coated with synthetic and biodegradable polymers. Significant decreases in both the water vapor and oxygen permeation rates were observed. With each technique the barrier performance was improved. However, among the techniques tested ALD was found to be most suitable. Our results moreover revealed that biodegradable polylactic acid-coated paperboard with a 25-nm thick layer of aluminum oxide grown by ALD on top of it showed promising barrier characteristics against water vapor and oxygen. [Copyright &y& Elsevier]

Abstract: Thin aluminum oxide coatings have been deposited at a low temperature of 80°C on various uncoated papers, polymer-coated papers and boards and plain polymer films using the atomic layer deposition (ALD) technique. The work demonstrates that such ALD-grown Al2O3 coatings efficiently enhance the gas-diffusion barrier performance of the studied porous and non-porous materials towards oxygen, water vapor and aromas. [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]

The influence of surface treatments including pigment coating, surface sizing and calendering on the me-chanical strength of hotmelt adhesive joints in pilot made cartonboards was studied. The mechanical strength of the joints was investigated using the Y-peel test device at 23°C and 50% relative humidity. Some of the samples were investigated with respect to the failure mode by scanning electron microscopy. The surfaces were characterized in terms of surface roughness, surface chemical composition, and adhesion behaviour. A strong adhesive bond displayed fibre tear. In addition to fibre tear, interfacial failure, i.e., failure between the cartonboard and the adhesive, was the main reason for fracture in the bonded assembly. The most im-portant factor controlling the integrity of adhesive joints seemed to be the real contact area. The adhesive joints showed significantly higher strength when the hotmelt adhesive was first applied onto the rougher car-tonboard of the assembly and then the smoother cartonboard was pressed on the adhesive than vice versa. The surface roughness of cartonboards mainly depended on whether the surface was pigment coated or not. Calendering displayed only a minor effect. No clear influence of surface chemical composition of the cartonboards on the adhesive joint strength was found due to the fact that changes in surface chemistry in this study also led to changes in surface roughness. The strongest adhesive joint was created between two medium-rough and surface-sized cartonboards. [ABSTRACT FROM AUTHOR]

This study explores the suitability of innovative packaging for local and organic food. Attitudes and opinions in local and organic food chains in Southern Finland were collected via eighteen semistructural interviews. The respondents were small-scale producers and processors of fish, meat, berries, and mushrooms, wholesalers, retailers, and institutional kitchens. The aim of this study was to understand factors promoting and preventing the penetration of innovative packaging solutions into the organic and local food market. A clear majority (86%) of respondents considered active and intelligent solutions to be equally suitable for local and organic food as for conventional food. However, less than half would actually use the technologies in their own products. [ABSTRACT FROM AUTHOR]

In this paper, we report ALD deposition of silicon dioxide using either thermal or plasma enhanced atomic layer deposition (PEALD). Several aminosilanes with differing structures and reactivity were used as silicon precursors in R&D single wafer ALD tools. One of the precursors was also tested on pilot scale batch ALD using O3 as oxidant and with substrates measuring 150×400mm. The SiO2 film deposition rate was greatly dependent on the precursors used, highest values being 1.5–2.0Å/cycle at 30–200°C for one precursor with an O2 plasma. According to time-of-flight-elastic recoil detection analysis measurements carbon and nitrogen impurities were relatively low, but hydrogen content increased at low deposition temperatures. [ABSTRACT FROM AUTHOR]

Abstract: This paper demonstrates opportunities for wood-based xylan derivatives to be used in coating applications. A route for extraction and purification of white and pure xylan from bleached birch kraft pulp is described as a part of the production of high adsorption and high crystalline pulp. Derivatization of the xylan during the extraction step was also demonstrated. Efficient derivatization of xylan to water soluble derivatives was achieved and promising results were obtained in primary application tests as a coating component in barrier coatings on board and as a binder component in pigment coating of offset paper. With the best xylan derivate coating, the barrier properties were better than with a commercial biopolymer coating, while oxygen permeability was roughly one third of that for a polyethylene terephthalate coating. Likewise, surface strength close to the reference latex as a binder in pigment coatings was achieved by a xylan derivative. This work is part of a platform of hemicellulose derivatives enabling novel application for this medium to high molar mass hemicellulose of high purity. [Copyright &y& Elsevier]

Novel nanostructured and high surface area tubular materials were produced combining electrospinning and atomic layer deposition processes with the removal of polymeric template via dissolution. The dissolution process changed the structure of the tube walls, and the smooth atomic layer deposition coating was transformed into a highly complex, coral-like structure. This material, which we have called 'nanocoral,' has a relatively high surface area, 323 m g, due to the interconnected cavities formed after the removal of the template. This kind of material has important potential applications, for example, in the fields of catalysts and filtration. [ABSTRACT FROM AUTHOR]