Paper size and paper sizing process
CA 2248014 A1 · Owner: Hercules Incorporated · Inventors: Smith, Bryan C.; Hassler, Thord G.; Schuetz, Jurgen F.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed are a paper size consisting essentially of a) alkyl ketene dimer and/or alkenyl succinic acid anhydride; b) degraded liquid cationic starch , having a cationic charge density of 0.5 to 3.5 meqv/g a degree of , substitution of more than 0.1 and a viscosity of less than 10000 cps (30 % by weight solution in water at 25 ~C); and c) water and a process for making , paper products in which this paper size is added to the pulp. The invention allows the production of AKD and/or ASA sizes on-site in paper plants using simple mixing equipment.
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 March 14, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 14, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 14, 2019.
- 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.