Cellulose derivative, process for preparing the same and sulfur dioxide gas permselective membrane comprising the same
CA 1280412 C · Owner: Tezuka, Yasuyuki · Inventors: Tezuka, Yasuyuki; Imai, Kiyokazu; Shiomi, Tomoo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Hydrocarbysulfinylethyl cellulose represented by the formula (I):, (I), wherein, X may be the same or different and represents hydrogen atom or hydrocarbylsulfinylethyl group represented by the formula (II):, (II) wherein, R may be the same or different and represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, with the average substitution degree with the hydrocarbylsulfinylethyl group of the formula (II) per glucose unit being at least 0.05, and sulfur dioxide gas permeation membrane comprising said cellulose derivative. This membrane is excellent in sulfur dioxide gas permselectivity.
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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 February 19, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 19, 2008.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.