Method of making organopolysiloxanes
CA 2061004 A1 · Owner: De La Croi Habimana, Jean · Inventors: De La Croi Habimana, Jean; Gilson, Jean-Marc
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of making organopolysiloxanes comprises contacting organosilicon compounds having at least one unit wherein R° is hydrogen, hydroxyl, a C1-18 hydrocarbon substituted hydrocarbon or hydrocarbonoxy group and a has a value of from 0 to 4 with a phosphonitrile halide AB wherein A, is a phosphonitrile halide cation X(PX2=N)nPX3+ wherein X is, halide and n is from 1 to 8 and B is an anion derived from a Lewis acid not containing a P atom, e.g. MX(v-t+1)R2t-. The method is particularly useful for condensation of silanol end-blocked siloxanes.
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 11, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 11, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 11, 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.