Papermaking compositions, process using same, and paper produced therefrom
CA 2177255 C · Owner: Sequa Chemicals, Inc. · Inventors: Hutcheson, Gary S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A chemical composition for use in the papermaking process to produce a paper having enhanced characteristics of brightness opaqueness, and sizing is provided. The process using the composition to make the paper and the paper made therefrom are also provided by the present invention. The composition employs a cationic softener base such as the mono- and distearamides of aminoethylethanolamine to enhance sizing, opacity and brightness. A surfactant such as an ethoxylated tallow amine or the reaction product of a saccharide and an acid, is used to ensure that the components of the composition remain dispersed therein and that the composition achieves uniform dispersibility on the paper. …
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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 November 24, 1993 and granted October 21, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 24, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 24, 2015.
- 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.