Amphoteric starches and process for their preparation
CA 1284639 C · Owner: Solarek, Daniel B. · Inventors: Dirscherl, Teresa A.; Jarowenko, Wadym; Solarek, Daniel B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Improved amphoteric starch derivatives containing tertiary amino or quaternary ammonium groups and anionic phosphate groups are disclosed. The derivatives which are defined by a minimum bound phosphorus content, a minimum viscosity and other criteria have use as wet-end additives and provide improved drainage properties in the manufacture of paper.
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
- Granted June 4, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 4, 2008.
- 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.