Organopolysiloxanes having bifunctional terminal siloxane units
CA 2132266 C · Owner: John, Peter · Inventors: John, Peter; Stepp, Michael
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to the organopolysiloxanes having the formula, R1Si(OSiR22X)2OSiR22O1/2aR3SiO1/2bR2SiOcRSiO3/2dSiO2e (1) where, R is optionally substituted C1- to C18-hydrocarbon radicals R1 is an optionally substituted C6- to C15-hydrocarbon radical having at least one phenyl ring, R2 is a C1- to C3-hydrocarbon radical X is a hydrogen atom or an organic or organosilicon functional group bonded via a divalent, optionally substituted C2- to C15-hydrocarbon radical, with one or more methylene units of the hydrocarbon radical being able to be replaced by oxygen atoms bonded on both sides to carbon atoms a is an integer of at least 1 and, b, c d and e are each 0 or a positive …
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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 September 16, 1994 and granted April 7, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 16, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 16, 2016.
- 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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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.