Abstract: Soluble salt-free, contaminant-free antioxidant pigments which are cyanamide derivatives of metals, are provided in combination with organic resin polymers, as protective mirror backing coatings.

Abstract: Soluble salt-free, contaminant-free antioxidant pigments which are cyanamide derivatives of metals, are provided in combination with organic resin polymers, as protective mirror backing coatings.

Abstract: Mirrors are formed in an environmentally compatible and substantially pollution-free manner by a sputtering process in which a transparent substrate such as glass has first sputtered upon it a primer layer and then a reflective layer of silver or other bright reflective metal. A barrier layer is provided over the reflective layer to protect the latter from corrosive environments. If the transmittance of the reflective layer is greater than zero percent, the barrier layer includes a different bright reflective metal sufficient to reduce the transmittance of the combined reflective and barrier layers to zero percent. The mirror includes a lead free polymeric protective layer spaced further from the transparent substrate than the barrier layer. The inclusion of zinc pigment in the polymeric coating provides sulfiding protection, and the use of an outer sputtered on film of zinc or zinc oxide provides substantial adhesion thereto of the polymeric coating.