Method for the manufacture of branched polysiloxane
CA 2090180 C · Owner: Ogawa, Takuya · Inventors: Suzuki, Toshio; Ogawa, Takuya
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is a novel method for the manufacture of branched polysiloxanes having the polysiloxane SiO4/2 unit as the branch center precisely bonded to one end of a diorganopolysiloxane. The present invention concerns a method for the manufacture of a branched polysiloxane characterized by reacting a linear polysiloxane with a reactive polysiloxane having halogen substitution.
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, 1993 and granted December 23, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 23, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 23, 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.