Wholly aromatic polyesters of isophthalic acid, terephthalic acid, p-hydroxybenzoic acid, hydroquinone and arylene diol
CA 2000486 C · Owner: Layton, Richard · Inventors: Stern, Brian Allen; Layton, Richard; Matzner, Markus
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Aromatic polyesters based on isophthalic acid terephthalic acid, p-hydroxybenzoic acid hydroquinone and an arylene diol are described. The five monomers are used in well-specified proportions and yield polymers that display an excellent overall combination of mechanical and thermal properties. The subject copolyesters have melting points of at least about 260° C; their heat distortion temperatures are at least about 200° C. They have fiber ratings of up to 3. The novel polymers can be melt-fabricated using standard injection molding extrusion and melt-, spinning techniques.
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 11, 1989 and granted November 5, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 11, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 11, 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.