Siloxane resins and method for making them
CA 2010789 C · Owner: Butler, Derek W. · Inventors: Butler, Derek W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Liquid organosiloxane MTQ resins of the general formula M x T y Q zn wherein M denotes a monofunctional T a trifunctional, and Q denotes a tetrafunctional siloxane unit is characterised by the fact that n has an average value of from 4 to 14 x+y is, not less than z and not more than 2 z and x/y has a value of from 2/1 to 9/1. The resin molecule has at least one reactive substituent as defined and can be made by a method comprising (I) adding together a tetraalkoxysilane a monoorganosilane and, a triorganosilane or hexaorganodisiloxane in an acidified aqueous medium provided the tetraalkoxysilane is not added to the aqueous medium prior to the other components (II) allowing, the components …
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
- Filed February 23, 1990 and granted January 12, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 23, 2012.
- 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.