Solid acrylic resin using a continuous tube reactor
CA 2218802 A1 · Owner: Wiggins, Michael S. · Inventors: Whyzmuzis, Paul D. (Deceased); Yosh, Jim; Boucher, Steve
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Described is a process for making acrylic resins suitable as polymeric surfactants used in emulsion polymerization as pigment grinding resins and for, preparing dispersions used as overprint varnishes. The feedstock is styrene .alpha.-methyl styrene, acrylic acid and a polymerization initiator and is preferably free of solvent. This mix is passed through a continuous tube reactor run at a controlled range of pressure and relatively low residence time and temperature. Optimally when the polymer/unreacted monomers blend exits the reactor and is devolatilized, the recovered monomers are used to make up part of the feedstock.
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 October 22, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 22, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 22, 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.