Silver recovery element and method
CA 2090232 C · Owner: Eastman Kodak Company · Inventors: Badger, John Stuart; Mc Guckin, Hugh Gerald
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A silver recovery element (10) for treating a photographic developer solution containing silver ions comprises a substrate (20) having thereon a hydrophilic colloid layer containing physical development nuclei. The invention also comprises a process for recovering silver from a photographic developer solution containing silver ions such process comprising contacting the solulion with the silver recovery element. The contacting is for a time sufficient to reduce the concentration of silver in the solution to a desired level. The recovery element and process for its use are useful in treating a a seasoned photographic developer solution containing silver ions.
Read the whole patent
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
- Filed June 25, 1992 and granted February 25, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 25, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 25, 2014.
- 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.