Paper mill press felt conditioner
CA 2039210 C · Owner: Betz Laboratories, Inc. · Inventors: Owiti, Clarice A.; Khan, Abdul Q.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to an improved press felt conditioning treatment which controls the deposition of polymerically flocculated particulate substances in a press felt. The treatment comprises applying to the felt an effective inhibiting amount of a conditioner comprising a combination of a polymethylnapthalene sulfonate and a type A phosphate ester comprising a nonyl phenol hydrophobe based phosphate ester having between 6 and 10 moles of ethylene oxide and a mono to diester ratio of approximately 60 to 40 or a type B phosphate ester comprising a tridecyl alcohol hydrophobe based phosphate ester having between 6 and 10 moles of ethylene oxide and a mono to diester ratio of about 60 to …
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 27, 1991 and granted February 6, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 27, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 27, 2013.
- 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.