Sophthalic acid glycol ester solution
CA 2433029 A1 · Owner: E.I. Du Pont De Nemours And Company · Inventors: Duan, Jiwen F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A substantially soluble solution of isophthalic acid in a glycol can be prepared and contacted with terephthalic acid its ester, its oligomer, or , combinations of two or more thereof. The solution can be used to incorporate isophthalic acid into polyester for bottle resins and fiber.
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 January 17, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 17, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 17, 2024.
- 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.