Aromatic diamine compounds, and methods for their preparation
CA 2028313 C · Owner: Yamaya, Norimasa · Inventors: Tanabe, Yoshimitsu; Yamaguchi, Keizaburo; Ohta, Masahiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is an aromatic diamine compound represented by the formula (I), ), (see fig. I) wherein R is H or CH3. Also disclosed is a bismaleimide compound represented by the formula (IV), (see fig. IV), wherein R is H or CH3 A resin forming composition comprising these compounds is also disclosed. The compounds are useful as raw materials for resins, and the resin forming composition and the resin can provide excellent heat resistance and impact resistance and low hygroscopicity.
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 October 23, 1990 and granted July 8, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 23, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 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.