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Expired Canadian patentCanada

Low ph preparation of cationic starches and flours

CA 1098655 A · Owner: United States Of America Represented By The Secretary, U.S. Department Of Commerce, Ntis · Inventors: Phillips, Bliss S.; Rankin, John C.

CIPO record

Overview

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Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A novel process is disclosed for preparing cationic starches and flours by reacting starch-containing materials in a dry state with a halohydrin at a pH of 9 or below without the necessity for subsequent alkali neutralization or washing. The resultant products have cationic properties remarkably superior to prior art cationic starches over a broad range of acid and alkaline pH's. In the manufacture of paper they serve as, excellent pigment retention and dry-strength improvement agents.

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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 April 7, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 7, 1998.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledMay 4, 1978
GrantedApril 7, 1981
Term endedApril 7, 1998
Patent numberCA 1098655 A
Classification (IPC)C08B31/00 +2 more

Timeline

Timeline From CIPO dates

1979198119831985198719891991199319951997Application filedMay 4, 1978Patent grantedApril 7, 1981Term endedApril 7, 1998

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.