Silver halide photographic material
CA 2059424 C · Owner: Yasuda, Shoji · Inventors: Okamura, Hisashi; Katoh, Kazunobu; Yasuda, Shoji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A silver halide photographic material comprising a support having thereon at least one silver halide emulsion layer, wherein the silver halide photographic material contains at least one compound represented by formula (I):, ED~Time~Ind~~(I), wherein ED represents a group capable of releasing (Time)t-Ind upon a reaction with an oxidation product of a developing agent; Time represents a divalent linking group; t represents 0 or 1; and Ind represents a group represented by formula (II):, (see formula I) wherein X represents a monovalent group; and s represents an integer of from 0 to 4. The compound represented by formula (I) is excellent in preservability and rapidly releases a development …
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 January 15, 1992 and granted January 2, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 15, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 15, 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.