Cyclic silylureas and process of preparation
CA 2129958 C · Owner: Osi Specialties Holding Company · Inventors: Bennett, Everette Wyman; Schilling, Curtis Louis, Jr.; Pepe, Enrico James
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention provides a class of cyclic silylureas and a process of preparing them which process comprises reacting a, cyclosilazane with an isocyanate containing moiety; a class of cyclosilazanes and process for making them which process comprises, heating an aminoalkylalkoxysilane in the presence of a basic catalyst at a temperature less than 100 °C at subatmospheric pressure; and aminoalkylalkoxysilanes and a process for making them which process comprises reacting a nitrile and a vinylsilane while heating in the presence of a base selected from the group consisting of (a) an alkali metal (b) alkali metal alkoxide, (c) an alkali metal amide (d) an, alkali metal hydride and (e) mixtures …
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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 December 20, 1993 and granted February 24, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 20, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 20, 2015.
- 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.