process for the production of teilnegativen using a more complex photographic negative materials with at least three for different regions of the spectrum sensitive silbersalzemulsionsschichten

摘要

796,054. Colour photographic processes FRAUNHOFER, H. VON., and COOTE H. E. July 28, 1954 [July 29, 1953], No 21050/53. Drawings to Specification. Class 98(2) For the production of colour separation records a negative multilayer film normally free from colour formers is exposed, developed, fixed, treated with a bleach to convert the uppermost silver image to a silver salt and then, in the manner described in Specification 795,186, contacted in the presence of hypo with a take-off film including a metallic sulphide to produce a silver sulphide image therein; the uppermost layer of the negative film is then removed and the procedure repeated to obtain a record in a second take-off film of the image of the intermediate layer; and the bottom layer, remaining untouched, serves as the third separation record. The process is further described in application to a negative film having a low melting point yellow filter layer beneath the uppermost blue sensitive layer whereby the latter may be removed when required with aid of hot water. The bleach concerned is described as being viscous. The images in the two take-off films may themselves be bleached and redeveloped so that all three records may be of silver.