Patent Yard Sign in
Expired Canadian patentCanada

Metal hydroxide crystallizer and filter

CA 2032931 C · Owner: Coin, Richard J. · Inventors: Coin, Richard J.; Noscal, Jay M.; Brown, Carl W. Jr.

CIPO record

Overview

Drawings and full text

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

Open the CIPO record

Abstract From the Canadian patent

The present invention comprises a closed-loop filter system for continuously removing a metal hydroxide precipitate from an alkali metal hydroxide solution. The filter system comprises a filter having a filter surface and a plurality of small diameter openings in said surface. The alkali metal hydroxide solution is impacted onto said filter surface, metal hydroxide precipitate agglomerating on said surface. The filter surface openings have an average diameter effective for said agglomerating. Means are provided to remove the agglomerated precipitate from said filter surface and to, separate the agglomerated precipitate from the alkali metal hydroxide solution, the agglomerated precipitate …

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

  • Filed December 21, 1990 and granted September 17, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 21, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 21, 2012.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledDecember 21, 1990
GrantedSeptember 17, 1996
Term endedDecember 21, 2010
Patent numberCA 2032931 C
Classification (IPC)B01D29/62 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedDec 21, 1990Patent grantedSep 17, 1996Term endedDec 21, 2010

Sources & verification

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