Siloxane copolymers containing alkenyl groups, their preparation and use
CA 2073813 C · Owner: Herzig, Christian · Inventors: Huettner, David; Deubzer, Bernward; Herzig, Christian
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Siloxane copolymers containing alkenyl groups are prepared by reacting an organic compound (1) containing at least two aliphatic double bonds of the general formula, R2(CR3=CH2)x in which R2 is a divalent, trivalent or tetravalent hydrocarbon radical having from 1 to 25 carbon atoms per radical R3 is a, hydrogen atom or an alkyl radical having from 1 to 6 carbon atoms per radical and x is 2, 3 or 4, with an organopolysiloxane (2) having an average of more than one Si-bonded hydrogen atom per molecule, in the presence of a catalyst (3) which promotes the addition of Si-bonded hydrogen to an aliphatic double bond in, which the ratio between the aliphatic double bond in the organic compound …
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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 July 14, 1992 and granted March 4, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 14, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 14, 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.