Water resistant security ink composition
CA 2085817 A1 · Owner: Raby, James M. · Inventors: Oswald, Thomas R.; Raby, James M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A security composition for use with an ink composition including diphenyl guanidine and acrylic resin. The ink composition may further include a glycol ether and a plasticizer and can be printed on paper, for example in the word "VOID". If bleach is used to attempt to alter the document the initially, colorless ink will form a colored image in the shapes or letters printed on the paper. The ink composition is resistant to leaching upon contact with, for example water.
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 December 18, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 18, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 18, 2014.
- 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.