Water-soluble copolymers, their preparation and their use
CA 1329677 C · Owner: Seelmann-Eggebert, Hans-Peter · Inventors: Kud, Alexander; Boeckh, Dieter; Hartmann, Heinrich
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Water-soluble copolymers having a K value of from 15 to 120 (determined on the sodium salt according to H. Fikentscher in aqueous solution at 25°C, a pH of 7 and a polymer concentration of the Na salt of 1% by weight) contain, in the polymerized form, a) from 99.5 to 80 mol % of one or more monoethylenically unsaturated C3-C6-monocarboxylic acids and b) from 0.5 to 20 mol % of one or more comonomers which possess two or more ethylenically unsaturated non-, conjugated double bonds, are derived from esters and are obtainable by esterification of, b1) monoethylenically unsaturated C3-C6-monocarboxylic acids with, b2) polyhydric alcohols of 2 to 6 carbon atoms poly-, alkylene glycols, …
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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 May 17, 1994. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 17, 2011.
- 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.