Yellow azomethine dyes
CA 1104577 A · Owner: Polaroid Corporation · Inventors: Idelson, Elbert M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Novel yellow ortho ortho' dihdroxy azomethine, dyes and metal complexes of such dyes which are particularly useful in photographic products and processes are presented by this invention. The novel yellow ortho ortho' dihydrozy, azomethine dyes have the following structural formula: where n' is the integer 1-8 and m' is the integer 1 or 2.
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
- Granted July 7, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 7, 1998.
- 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.