Photographic elements including nondiffusible photographic couplers having the ballast group terminated by a hydroxyphenylsulfonyl or -sulfinyl group
CA 1188913 A · Owner: Eastman Kodak Company · Inventors: Lestina, Gregory J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Photographic couplers comprising a coupler moiety and a ballast moiety have advantageous properties when the ballast moiety is terminated with a hydroxyphenylsulfonyl or hydroxyphenylsulfinyl group. The couplers are useful in photographic emulsions and elements. Illustrative couplers are represented by the structural formula: where:, COUP represents a coupler moiety; p is 1 or 2;, q is 1 to 3; and, L is direct linkage or a bivalent linking group.
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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 June 18, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 18, 2002.
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Timeline
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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.