Process for preparation of polyalkyl hydroxyaromatics
CA 2381377 A1 · Owner: Huntsman Petrochemical Corporation · Inventors: Su, Wei-Yang
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Polyalkyl hydroxyaromatics may be prepared from polyalkylenes and hydroxyaromatics in the presence of an acid catalyst and an organic solvent having a boiling point range with an initial boiling point value of below or about the boiling point of the selected hydroxyaromatic reactants and final boiling point of above or equal to about the boiling point of alkylhydroxyaromatic by-product of the reaction. Using this method accumulation of undesirable alkylhydroxyaromatic by-product/s in a reaction vessel may be minimized, and/or viscosity of polyalkyl hydroxyaromatic product reduced, allowing for increased ease of transfer and transportation.
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 August 21, 2000. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 21, 2020.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 21, 2022.
- 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.