Low coefficient of variation tabular grain emulsion
CA 2067606 A1 · Owner: Tsaur, Allen K. · Inventors: Tsaur, Allen K.; Tsaur, Allen K.; Kam-Ng, Mamie
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure, A photographic emulsion is disclosed containing a coprecipitated grain population exhibiting a coefficient of variation of less than 10 percent. The coprecipitated grain population consists essentially of tabular grains which are at least 50 mole percent bromide, based on silver and, which have a mean thickness in the range of from 0.080 to 0.3 µm, and a mean tabularity of greater than 8.
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 April 29, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 29, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 29, 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.