Hard coating for polymer substrates through lamination and peeling of porous anodized zirconia

Transparent and hard zirconia (ZrO2) films with thicknesses in the range of 1.5 to 1.8 microm were successfully formed on various polymer surfaces, i.e., polycarbonate (PC), polystyrene (PS), polyethylene terephthalate (PET) and polymethylmethacrylate (PMMA) with excellent adhesion and without cracking, while preserving their bulk properties. Our process is based on a lamination of porous anodized ZrO2 membranes (PAZMs) to the polymer surfaces through capillary action, followed by simple peeling with tweezers to remove the unanodized metal Zr foil. The resulting PAZM-laminated surfaces exhibited excellent surface chemical and physical durability. Our technique also allowed the reuse of a single Zr foil piece multiple times for several anodization and lamination cycles.