Water soluble polymers
CA 1265635 C · Owner: Hawe, Malcolm · Inventors: Farrar, David; Hawe, Malcolm
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A water soluble polymer containing acid groups can be fractionated into higher and lower molecular weight fractions by partial neutralisation of the polymer as a solution in a blend of water and a low molecular weight alcohol and separating the resultant aqueous and organic phases. Pigment dispersions contain, as dispersing agent novel water soluble polymers containing acid groups preferably polyacrylic acid or copolymers of polyacrylic acid with AMPS, having polydispersity below 1.5 and molecular weight in the range about 1,000 to about 5,000.
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 February 6, 1990. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 6, 2007.
- 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.