Method to increase the level of .alpha.-glycol in liquid epoxy resin
CA 2174427 A1 · Owner: Hairston, Thomas J. · Inventors: Hairston, Thomas J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The performance of expoxy retains in several end-uses is enhanced by the presence of small quantities of hydrolyzed resin terminated by .alpha.-glycol groups. The invention is a process in which a mixture that contains liquid epoxy resin and water is reacted at elevated temperatures in order to hydrolyze epoxy groups into .alpha.-glycol group characterized in that (1) the reaction temperature is between 130°C and 200 ° C; (2) the reaction mixture contains between 0.5 and 10 parts water per 100 parts resin by weight; and (3) the mixture contains 0 to 1 weight percent organic solvents and 0 to 100 ppm each of organic acids organic diacids, phosphonium compounds and alkali or, alkaline earth …
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 February 14, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 14, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 14, 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.