3-(substituted-amino)(aryl or hetercaryl)- methyl-1h-indoles as color formers in pressure- sensitive and thermal imaging systems
CA 1162191 A · Owner: Sterling Drug Inc. · Inventors: Hung, William M.; Schmidt, Paul J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
3-(Substituted-amino)(aryl or heteroaryl)methyl-1Hindoles which are useful as color formers in pressure-sensitive carbonless dupllicating systems and thermal markling systems are prepared by reacting 3-(arylsulfonyl)(aryl or heteroaryl)methyl- 1H-indoles with amines or precursors thereof in the presence of a base.
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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 February 14, 1984. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 14, 2001.
- 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
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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.