Dispersing auxiliary for preparing cellulose ethers
CA 1193250 A · Owner: Hoechst Aktiengesellschaft · Inventors: Felcht, Utz-Hellmuth; Perplies, Eberhard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
29-, Abstract of the Disclosure, In modern processes for preparing cellulose ethers containing one or more types of substituents such as MC, CMC, HEC, HPC, MHEC or EHEC cellulose is reacted with an etheri-, fying agent in the presence of water base and at least one, inert organic solvent (as a dispersing auxiliary). Dimethoxyethane (ethylene glycol dimethyl ether) is employed as a new organic solvent for these syntheses, particularly in quantities of 1 to 30 parts by weight per part by weight of cellulose.
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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
- Granted September 10, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 10, 2002.
- 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.