Method of processing photographic silver dye bleach materials
CA 1087629 A · Owner: Ciba-Geigy Ag · Inventors: Schellenberg, Matthias; Meier, Max; Chylewski, Christoph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of processing photographic silver dye bleach materials which have been exposed imagewise is provided. The process steps are (1) silver developing, (2) dye bleaching (3) silver bleach-, ing and (4) fixing. The treatment baths for the process steps (2), (3) and (4), or the combined treatment baths useful for process step (3) with at least one the process steps (2) or (4) contain water-soluble tertiary phosphines as silver ligands. These phosphines effect an acceleration of the dye and silver bleaching and they are further suitable stabilizers and optionally antioxidants which yield stable treatment baths
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted October 14, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 14, 1997.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.