Photochromic films - of silver, tantalum and tungsten oxides sputtered on glass and heat treated

摘要

A photochromic film is formed on a glass substrate by (a) sputtering a mixed oxide film of oxides of Ag, and Ta and/or W onto the substrate, (b) removing excess silver oxide, e.g. by immersion in nitric acid soln., until the film becomes colourless, and (c) heating the substrate and film at =300 degrees C for =1/2 hr. Films have good resolution and ease of bleaching depends on compsn. and heat treatment.