Alkylation resins from polycyclic aromatic compounds
CA 2129696 C · Owner: Eastman Chemical Resins, Inc. · Inventors: Klosiewicz, Daniel W.; Biswas, Atanu
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The alkylation resins of this invention comprise the alkylation reaction product of (a) at least one substituted or unsubstituted polycyclic aromatic compound and (b) at least one ethylenically unsaturated hydrocarbon monomer having at least two carbon-carbon double bonds that reacts with the polycyclic aromatic compound by alkylation in the presence of an acid catalyst, wherein the ratio of (a) to (b) in the resin is 1:9 to 3:1 by weight. The resins have a weight average molecular weight of less than 10,000 measured by size exclusion chromatography, and a Ring & Ball softening point of 50° to 250°C. Because of their high softening point and low molecular weight the resins are, useful in a …
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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 August 8, 1994 and granted August 31, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 8, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 8, 2016.
- 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.