Nucleated high contrast photographic elements containing thioether compounds to inhibit pepper fog and restrain image spread
CA 2112232 C · Owner: Eastman Kodak Company · Inventors: Kerr, Donald Laurens; Machonkin, Harold Ihor
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Silver halide photographic elements which are capable of high contrast-development and are especially useful in the field of graphic arts have incorporated therein a hydrazine compound which functions as a nucleator an amino compound which, functions as an incorporated booster. and a thioether compound which functions to inhibit pepper fog and restrain image spread.
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 July 22, 1992 and granted February 4, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 22, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 22, 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.