Process for producing vinyl chloride resin
CA 2043041 A1 · Owner: Kaneko, Ichiro · Inventors: Fujimoto, Tatsuya; Kaneko, Ichiro; Fujiwara, Makoto
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for producing a vinyl chloride polymer by polymerizing a monomer comprising vinyl chloride by suspension polymerization in a polymerization vessel on the inner wall surface of which a coating of a polymer scale preventive agent is formed, comprising the steps of applying a high-speed shearing force to a mixture comprising water the monomer, a, polymerization initiator and (A) a dispersant comprising a, partially saponified polyvinyl alcohol having a specified average degree of polymerization and a specified degree of saponification plus (B) a dispersant comprising a hydroxypropylmethylcellulose which has a specified methoxyl substitution degree, a specified hydroxypropoxyl …
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 May 22, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 22, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 22, 2013.
- 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.