Sterically hindered phenolic ester photographic coupler dispersion addenda and photographic elements employing same
CA 1268981 C · Owner: Eastman Kodak Company · Inventors: Krishnamurthy, Sundaram
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure Photographic coupler dispersion addenda comprising phenolic esters of di-, tri- and tetra-carboxybenzene derivatives having bulky ortho substituents are described for incorporation in photographic emulsions and elements. The solvents are preferably employed in the cyan layer to protect the cyan dye against ferrous ion reduction. The solvents also provide improvements in yellow dye stability to light and cyan dye stability to light, heat and humidity.
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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 May 15, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 15, 2007.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.