Century Dictionary and Cyclopedia
- n photoceramics A process of producing burnt-in photographic images on porcelain, glass, or similar materials. Tessié du Motay's method consists in carefully removing a collodion positive from its glass support and floating it in a toning-bath containing iridium and gold chlorids. The film is next carefully floated to the surface of the enameling-tablet, and after drying is heated in a muffle-furnace. At a certain stage of the baking an enamel composition, suspended in collodion, is poured over the picture and burned on. This must be repeated five or six times until the glaze is of sufficient thickness and the picture of the desired color. By this process an image is obtained which consists of pure metallic silver, gold, and iridium in an extremely fine state of division, fixed to the surface of an imperishable tablet, and protected by an equally hard, permanent, and impermeable glaze. Ceramic colors may be applied and burnt in during the making of such an enamel picture.