Continuous production of reduced gel content hydroxylated addition polymers
CA 2202902 C · Owner: S. C. Johnson & Son, Inc. · Inventors: Chylla, Richard W.; Campbell, J. David; Popli, Rakesh K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is disclosed for the continuous production with reduced gel , formation, of free radical addition polymers from ethylenically unsaturated monomers containing at least one free hydroxyl group such as 2-hydroxyethyl methacrylate, from about 0 to about 5 % by weight of an alpha-beta unsaturated carboxylic acid such as acrylic acid or methacrylic acid and the remainder of , the monomers used are free radical addition copolymerizable compounds such as styrene, methyl methacrylate and butyl acrylate. The free radical addition polymerization is conducted at from about 150 ~C to about 310 ~C under superatmospheric pressure in the presence of one or more solvents. The solvent or the …
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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 October 13, 1995 and granted June 20, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 13, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 13, 2017.
- 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
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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.