Production of terephthalate esters by degradative transesterification of scrap or virgin terephthalate polyesters
CA 2012227 C · Owner: Geon Canada Inc. · Inventors: Dupont, Louis; Gupta, Ved P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the production of terephthalate diesters having the following formula (I). (see formula I) Substituents R and R' are 'the same or different and represent a straight chain, branched or cyclic aliphatic group, an aromatic group, an alkaryl group or an aralkyl group, each group having from 6 to 20 carbon atoms. The process involves reacting a terephthalate polyester with a high molecular weight alcohol or a mixture of high molecular weight alcohols each having from 6 to 20 carbon atoms, in the presence of a catalyst and recovering the desired compound according to formula (I). This process is particularly useful for recycling scrap terephthalate polyester products such as those …
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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 March 15, 1990 and granted August 14, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 15, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 15, 2012.
- 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.