Modified acid dyestuff
CA 1279869 C · Owner: Hohener, Alfred · Inventors: Smith, Roy E.; Hohener, Alfred
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract of the Disclosure Crystalline modification, designated ".beta." of the dye of the, structure, wherein M is an alkali metal ion alkaline earth metal ion or the, ammonium ion. The .beta.-crystalline modification of the dye is easier to isolate from water and gives filter cakes of higher solids and color content. The .beta.-form is also more suitable for making liquid formulations of the dye; the liquid formulations of the crystalline modification have lower viscoity and better dispersion stability than liquid formulations of non-modified form. The .beta.-modification of the dye is obtained by heating an aqueous slurry of the dye at about 80° to 120°C optionally under pressure and pH …
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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 5, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 5, 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.