Improvements in and relating to the production of metal casts from gelatine and likeheat-developable reliefs

摘要

419,368. Casting processes. KODAK, Ltd., Kirgsway, London.-(Assignees of Murray, A. ; Kodak Park, Rochester, New York, U.S.A.) May 11, 1933, No. 13690. Convention date, May 16, 1932. [Class 83 (i).] Mould materials.-Metal casts are produced from gelatin or like heat-developable reliefs by simultaneously developing the relief on a previously-exposed surface and making the cast therefrom. The surface is preferably coated with a thin layer of a plastic lacquer. A suitable layer for the relief comprises gelatine, ferric ammonium oxalate, sodium dihydrogen phosphate and ammonium nitrate, and may be applied to paper. This layer is then coated with a lacquer consisting of cellulose nitrate, tricresyl phosphate and ethyl acetate, exposed, and developed by pouring thereover a molten alloy which simultaneously forms the metal cast. The lacquer layer may be applied at any stage before development. A resin varnish may also be used as a lacquer. Specification 390,881, [Group XX], is referred to.