Phosphorus compounds
CA 2042008 C · Owner: Ciba Specialty Chemicals Holding Inc. · Inventors: Scharf, Wolfgang; Flury, Peter
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Compounds of general formula I, wherein X1 is chloro or bromo X2 is chloro, bromo or hydrogen, and, Y is O or S and, R1 and R2 are each independently of the other C1-C4alkyl and, R3 and R4 is a group of formula II which carries identical or different substituents and wherein R1 R2, X1 and , X2 are as, defined above, or R3 and R4 when taken together, form a group of formula III wherein R1 and R2 any as defined above are very suitable flame retardants for polymers.
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 May 7, 1991 and granted October 2, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 7, 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.