Lubricants for refrigeration compressors
CA 2007374 C · Owner: Mcgraw, Philip W. · Inventors: Ward, Eldon L.; Mcgraw, Philip W.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Lubricant base compositions for compression refrigeration are composed of 95 to 5 percent by weight of polyether polyols having a number average molecular weight of from 400 to 5000 and from 5 to 95 percent of esters made from polyhydric alcohols with alkanols acids or esters made from alkanedioic acids with alkanols. A refrigeration fluid is made from the base composition with the addition of selected hydrochlorofluorocarbons and hydrofluorocarbons so that the base composition is miscible with the refrigerant in the range of from -20°C to greater than 65°C.
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 January 9, 1990 and granted October 10, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 9, 2012.
- 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.