Silver halide imaging materials
CA 2077938 A1 · Owner: Newman, Stephen · Inventors: Wallis, Julian M.; Hall, Kevin P.; Newman, Stephen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Silver Halide Imaging Materials A black and white photographic element comprising as a photosensitive medium a layer of a silver halide emulsion characterised in that the photosensitive medium comprises in the same layer or in an adjacent layer thereto a developer comprising a substantially nondiffusing polymeric compound having as a component part of its structure a plurality of units having a nucleus of general formula (I):, (I), wherein;, each Z independently is a member selected from the group consisting of -OH and a group which leaves an -OH residue when contacted with an alkali, (pH ?10) at temperatures of ?50°C.
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 September 10, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 10, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 10, 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.