Surface sizing of cellulose-based products
CA 2250235 A1 · Owner: Eka Chemicals Ab · Inventors: Tsai, Yi-Guan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method of surface sizing cellulose-based products and to an aqueous sizing composition. The method comprises applying to the surface of cellulose-based products an aqueous dispersion of a copolymer obtainable by free-radical emulsion polymerization of a monomers mixture comprising at least one monomer selected from the group consisting of styrene and derivatives thereof; at least one monomer selected from the group consisting of esters of ethylenically unsaturated carboxylic acids and alkanols; and at least one monomer selected from the group consisting of ethylenically unsaturated carboxylic and sulfonic acids and salt thereof; optionally in combination …
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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
- Filed March 26, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 26, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 26, 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.