Barrier coatings on packaging films are still an elusive area in the industry as to how they really function. It is hard to tell why they are functional in some applications and fail under the same conditions in others. Barrier characteristics of a lamination structure of PET/Print/adh/MPET/adh/PE compared to a PET/print/metalization/PE construction of varying thicknesses were evaluated. The physical and mechanical properties of these layers were evaluated. The effect of metalizing on top of a printed structure versus laminating a pre-printed reverse PET to a pre-laminated Metalized PET to PE was evaluated. The barrier aspects and appearance of the printed multilayer structures were deemed to be inferior. The tensile strength although being lower was in a functional range. The tear strength was higher in the thinner layered material. The optical surface scans of the metalized PET on top of the print layer showed pinholed areas where the ink laydown which was heavier in some areas than others due to surface morphology. These defects were considered as the main responsibility for the poor barrier values found. Additional work needs to be explored to implement this technology commercially from both an aesthetic and barrier aspect.
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