Polymerization of vinyl chloride
CA 2225274 C · Owner: Mitsui Chemicals, Incorporated · Inventors: Nakamura, Ichisaburo; Ozawa, Masaaki; Takahashi, Akihiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention provides a process for polymerizing a vinyl chloride monomer wherein the vinyl chloride monomer is subject to homopolymerization or (co)polymerization with a monomer copolymerizable with the vinyl chloride monomer in an aqueous solvent, comprising applying in advance a coating liquid containing a cocondensation product obtained by reacting either a phenothiazine derivative and an aldehyde or a phenothiazine derivative, a naphthol derivative and an aldehyde to give an initial condensation product and then reacting the initial product with a polyphenol, to an inner wall of a polymerization tank and parts of an apparatus in contact with the monomers during the polymerization …
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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 December 19, 1997 and granted June 25, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 19, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 19, 2019.
- 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.