Stabilizers for colour photographic recording materials
CA 2023945 A1 · Owner: Rody, Jean · Inventors: Rody, Jean; Leppard, David G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Stabilizers for colour photographic recording materials Abstract, Colour photographic recording material containing in at least one of the chromogenic, colour photographic layers as a stabilizer, at least one compound of the formula I (I), in which R1 is, for example, alkyl cycloalkyl, cycloalkyl substituted by alkyl groups phenyl or aralkyl, R2 is, for example, H alkyl, cycloalkyl, cycloalkyl substituted by alkyl groups, phenyl or aralkyl and R3 is H or CH3 and n is the number 1 or 2 in which, if n, is 1, and R4 is, for example alkyl or C3-C20 alkyl which is interrupted by -O- -S- or -NR7- and, is unsubstitued or substituted by -OH or is a group of the formula, or , and R24 is alkyl having …
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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
- Filed August 24, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 24, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 24, 2012.
- 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.