"4,4'-bis(phthalimido)diphenyl sulfone compounds, processes for their production and flame retardant polymer compositions containing them
CA 1330563 C · Owner: Kawabata, Koji · Inventors: Matsuba, Takao; Oyama, Kiyotaka; Kubo, Masashige
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A 4,4'-bis(phthalimido)diphenyl sulfone compound having the formula:, (I), wherein X is a halogen atom k = 0 to 4, ? = 0 to 4, m = 0 to, 4 and n = 0 to 4 provided k+?+m+n>1. (I) was prepared by reacting a phtalic anhydride of the formula: (2), with a 4,4'-diaminodiphenyl sulfone of the formula: (3), (I) are useful as flame retardants for polymers having high melting points, and such polymers comprising (I) accomplish excellent weather resistance and heat resistance.
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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
- Granted July 5, 1994. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 5, 2011.
- 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.